UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

Form 10-K

(Mark One) 
þANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934
 For the fiscal year ended December 31, 2016
 or
December 31, 2019
oOr
TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934
 
For the transition period from                to


Commission file number: 000-22339

RAMBUS INC.
(Exact name of registrant as specified in its charter)

Delaware94-3112828
(State or other jurisdiction of
incorporation or organization)
(I.R.S. Employer
Identification Number)
  
1050 Enterprise Way
Suite 700 
Sunnyvale,California94089
(Address of principal executive offices)(Zip Code)


Registrant’s telephone number, including area code:
(408) (408462-8000



Securities registered pursuant to Section 12(b) of the Act:
Title of Each ClassTrading Symbol(s)Name of Each Exchange on Which Registered
Common Stock, $.001 Par ValueRMBSThe NASDAQ Stock Market LLC
  (The NASDAQ Global Select Market)
Securities registered pursuant to Section 12(g) of the Act:
None



Indicate by check mark if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act.  Yes þ     No o


Indicate by check mark if the registrant is not required to file reports pursuant to Section 13 or Section 15(d) of the Act.  Yes o     No þ


Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days.  Yes þ     No o


Indicate by check mark whether the registrant has submitted electronically and posted on its corporate Web site, if any, every Interactive Data File required to be submitted and posted pursuant to Rule 405 of Regulation S-T (§232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit and post such files). Yes þ No o

Indicate by check mark if disclosure of delinquent filers pursuant to Item 405 of Regulation S-K (§229.405 of this chapter) is not contained herein, and will not be contained, to the best of the registrant’s knowledge, in definitive proxy or information statements incorporated by reference in Part III of this Form 10-K or any amendment to this Form 10-K. þ


Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, or a smaller reporting company, or an emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer”filer,” “smaller reporting company” and “smaller reporting“emerging growth company” in Rule 12b-2 of the Exchange Act. (Check one):

Large accelerated filerþ
Accelerated filer ¨
Non-accelerated filer ¨
Smaller reporting company ¨
Emerging growth company   (Do not check if a smaller reporting company) 


If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act.

Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Act).  Yes o     No þ


The aggregate market value of the Registrant’s Common Stock held by non-affiliates of the Registrant as of June 30, 20162019 was approximately $1.0$1.1 billion based upon the closing price reported for such date on The NASDAQ Global Select Market. For purposes of this disclosure, shares of Common Stock held by officers and directors of the Registrant and persons that may be deemed to be affiliates under the Act have been excluded. This determination of affiliate status is not necessarily a conclusive determination for other purposes.


The number of outstanding shares of the Registrant’s Common Stock, $.001 par value, was 111,176,433112,429,523 as of January 31, 2017.2020.


DOCUMENTS INCORPORATED BY REFERENCE


Certain information is incorporated into Part III of this report by reference to the Proxy Statement for the Registrant’s annual meeting of stockholders to be held on or about April 20, 201730, 2020 to be filed with the Securities and Exchange Commission pursuant to Regulation 14A not later than 120 days after the end of the fiscal year covered by this Form 10-K.






TABLE OF CONTENTS


 
 






NOTE REGARDING FORWARD-LOOKING STATEMENTS
This Annual Report on Form 10-K (“Annual Report on Form 10-K”) contains forward-looking statements within the meaning of Section 27A of the Securities Act of 1933 and Section 21E of the Securities Exchange Act of 1934. These forward-looking statements include, without limitation, predictions regarding the following aspects of our future:
Success in the markets of our products and services or our customers’ products;
Sources of competition;
Research and development costs and improvements in technology;
Sources, amounts and concentration of revenue, including royalties;
Success in signing and renewing license agreements;
Terms of our licenses and amounts owed under license agreements;
Technology product development;
Dispositions, acquisitions, mergers or strategic transactions and our related integration efforts, including our recent acquisition of Smart Card Software Ltd., the assets of Semtech Corporation's Snowbush IP group and Inphi Corporation's Memory Interconnect Business;efforts;
Impairment of goodwill and long-lived assets;
Pricing policies of our customers;
Changes in our strategy and business model, including the expansion of our portfolio of inventions, products, software, services and solutions to address additional markets in lighting, memory, chip mobile payments, smart ticketing and security;
Deterioration of financial health of commercial counterparties and their ability to meet their obligations to us;
Effects of security breaches or failures in our or our customers’ products and services on our business;
Engineering, sales and general and administration expenses;
Contract revenue;
Operating results;
International licenses, operations and expansion;
Effects of changes in the economy and credit market on our industry and business;
Ability to identify, attract, motivate and retain qualified personnel;
Effects of government regulations on our industry and business;
Manufacturing, shipping and supply partners and/or sale and distribution channels;
Growth in our business;
Methods, estimates and judgments in accounting policies;
Adoption of new accounting pronouncements;
Effective tax rates;rates, including as a result of the new U.S. tax legislation;
Restructurings and plans of termination;
Realization of deferred tax assets/release of deferred tax valuation allowance;
Trading price of our common stock;
Internal control environment;
The level and terms of our outstanding debt and the repayment or financing of such debt;
Protection of intellectual property;
Any changes in laws, agency actions and judicial rulings that may impact the ability to enforce intellectual property rights;
Indemnification and technical support obligations;
Equity repurchase plans;
Issuances of debt or equity securities, which could involve restrictive covenants or be dilutive to our existing stockholders;

Effects of fluctuations in currency exchange rates;
Outcome and effect of potential future intellectual property litigation and other significant litigation; and
Likelihood of paying dividends.
You can identify these and other forward-looking statements by the use of words such as “may,” “future,” “shall,” “should,” “expects,” “plans,” “anticipates,” “believes,” “estimates,” “predicts,” “intends,” “potential,” “continue,” “projecting” or the negative of such terms, or other comparable terminology. Forward-looking statements also include the assumptions underlying or relating to any of the foregoing statements.
Actual results could differ materially from those anticipated in these forward-looking statements as a result of various factors, including those set forth under Item 1A, “Risk Factors.” All forward-looking statements included in this document are based on our assessment of information available to us at this time. We assume no obligation to update any forward-looking statements.

PART I
Rambus XDRTM, CryptoFirewallTM, CryptoMediaTM, CryptoManagerTM, TruEdgeTM and MicroLens® are trademarks, registered trademarks or copyrightsis a trademark of Rambus Inc. Other trademarks or copyrights that may be mentioned in this Annual Report on Form 10-K are the property of their respective owners.



Item 1.Business
Overview
Rambus creates innovative hardwareis a premier Silicon IP and software technologies, driving advancements fromChip provider, delivering high-speed interface and embedded security solutions to make data faster and safer. With 30 years of innovation, we also continue to develop and license the data centerfoundational technology essential to the mobile edge. Ourall modern system on chips customizable(SoCs) and computing systems. The Company delivers a broad range of semiconductor solutions including architecture licenses, high-speed physical and digital controller interface IP cores, patent licenses, software, services,Security IP cores and other innovations improveprotocols, and memory interface Chips.
Our strategic objectives are to focus our product portfolio and research around our core strength in semiconductor technologies, optimize the competitive advantageCompany for operational efficiency, and leverage our strong cash generation to re-invest for growth. We continue to maximize synergies across our businesses and customer base, leveraging the significant overlap in our ecosystem of customers, partners and influencers. By delivering comprehensive solutions for secure, connected semiconductors, we bring better value to our customers and improved profitability for the Company.
In 2019, we redefined our perimeter through the successful divestiture of our customers. We collaborate withPayments and Ticketing businesses, which allowed us to focus the industry, partnering withCompany on providing leading ASICsolutions for the semiconductor market thus becoming a single reportable segment. The Rambus product and SoC designers, foundries, IP developers, processor companies, EDA companies and validation labs. Our innovations are integrated into a wide range of devices and systems, powering and securing diverse applications, including Big Data, Internet of Things, mobile, consumer and media platforms.

While we have historically focused our efforts on the development of technologies for memory, SerDes and other chip interfaces, we have expanded our portfolio of inventions and solutions to address chip and system security, mobile payments and smart ticketing. We intend to continue our growth into new technology fields, consistent with our mission to create value through our innovations and to make those technologies available through the shipment of products, the provisioning of services,roadmap, as well as our licensing business models. Keygo-to-market strategy, is driven by the application-specific requirements of our focus markets. This not only allows us to better serve our efforts continuestraditional data center and communications markets, but also to be hiringexpand into new, fast-growing markets that demand the highest levels of performance and retaining world-class inventors, scientistssecurity, including automotive, artificial intelligence (AI), Internet of Things (IoT) and engineersgovernment.
We demonstrated continued execution and success across our product lines throughout the past year, with combined annual revenue from our Memory Interface Chips and Silicon IP businesses up 64% year over year to lead$114.5 million. Memory Interface Chips was the development and deployment of inventions and technology solutions for our fields of focus.

Our inventions and technology solutions are offered to our customers through patent, technology, software and IP core licenses, as well as product sales and services. Today, our primary source of revenue is derived from patent licenses, through which we provide our customers a license to use a certainfastest growing portion of the business with revenue almost doubling year over year, and Silicon IP drove sustained revenue growth with multiple design wins at tier-1 SoC customers across our broad portfolio of patented inventions. Royaltiestarget markets. Patent Licensing remains stable following the structural step down in 2019, with the decline offset by growth in product revenue. Revenue from patent licensesproducts accounted for 73%33%, 84%17%, and 88%9% of our consolidated revenue for the years ended December 31, 2016, 20152019, 2018 and 2014,2017, respectively.

Memory Interface Chips
Our strategy isMade for high speed, reliability and power efficiency, our DDR memory interface Chips for registered, load-reduced and non-volatile dual in-line memory modules (RDIMM, LRDIMM and NVDIMM, respectively) deliver top-of-the-line performance and capacity to continue to augment our patent license business model to provide additional technology, products and services while creating and leveraging strategic synergies to increase revenue. In supportthe next wave of our strategy, we acquired four businesses in 2016 in the fields of mobile payments, smart ticketing, memory buffer chips and SerDes IP cores. On January 25, 2016, our Security division completed the acquisition of Smart Card Software, Ltd. (“SCS”), a privately-held company incorporated in the United Kingdom. Through this purchase we acquired two complementary businesses: Bell Identification Ltd., a leader in mobile payments, and Ecebs Ltd., a leading supplier of smart ticketing systems. We believe these businesses complement our security division by allowing us to extend its foundational security technology to offer differentiated, value-added security solutions to its customers.

On August 4, 2016, our Memory and Interfaces division completed the acquisition of all the assets of Inphi’s Memory Interconnect Business. The acquisition included product inventory, customer contracts, supply chain agreements and intellectual property. On August 5, 2016, our Memory and Interfaces division completed the acquisition of the assets of Semtech’s Snowbush IP group. Snowbush IP, formerly part of Semtech’s Systems Innovation Group, is a provider of silicon-proven, high-performance serial link solutions. We believe these acquisitions strengthen our market position for memory buffer chip products and bolster our SerDes and IP offerings enabling us to better address the needs of the server, networkingenterprise and data center market.

Organization

We have organized our business into four operational units:

Memoryservers. Rambus offers DDR5, DDR4 and Interfaces (MID)
Security (RSD)
Emerging Solutions (ESD)
Lighting (RLD)

As of December 31, 2016, MID and RSD met quantitative thresholdsDDR3 memory interface Chips to enable increased memory capacity, while maintaining peak performance for disclosure as reportable segments. Results for ESD and RLD are shown under “Other.” For additional information concerning segment reporting, see Note 6, “Segments and Major Customers,” of Notes to Consolidated Financial Statements of this Form 10-K.

Memory and Interfaces

There are four main areas of focus in our Memory and Interface Division: mobile memory, server-based memory, serial link designs, and custom solutions. The primary markets for these technologies include: (1) DRAM devices; (2) NAND devices; (3) System-on-Chip (SoC) devices; (4) silicon physical IP; and (5) memory buffer chips. In these markets, memory interfaces, serial link transitions, processor and SoC microarchitecture transitions or overall process technology node transitions provide opportunities. For plug-in systems, there is a strong desire to reduce power consumption for both economic and environmental

reasons while still providing increased computing capability. At the chip level, it becomes increasingly difficult to maintain signal integrity and power efficiency as data transfer speeds rise to support more powerful, multi-core processors.

To address these challenges and enable the continued improvement of electronics systems, ongoing innovation is required. The many contributions and patented innovations developed by Rambus scientists and engineers have been, and continue to be, critical in addressing some of the most difficult chip and system challenges. The foundations of MID are world-class memory architectures and high-performance serial link technologies that are brought to market through three main business initiatives: (1) patent licensing; (2) silicon IP core licensing; and (3) chipsets.

Patent Licensing

Our traditional patent licensing program remains our primary source of revenue. Our patent licenses provide our customers a license to use a certain portion of our portfolio of patented inventions in the customer’s own digital electronics products, systems or services. The licenses may also define the specific field of use where our customers may use or employ our inventions in their products. License agreements are structured with fixed, variable or a hybrid of fixed and variable royalty payments over certain periods ranging up to ten years. Leading consumer product, industrial, semiconductor and system companies such as AMD, Broadcom, Cisco, Freescale, Fujitsu, GE, IBM, Intel, LSI, Micron, Nanya, NVIDIA, Panasonic, Qualcomm, Renesas, Samsung, SK hynix, STMicroelectronics, Toshiba and Xilinx have licensed our patents for use in their own products. The vast majority of our patents were secured through our internal research and development efforts across all of our business units.

Silicon IP Core Licensing

Our IP core licensing program offers a suite of memory and SerDes PHY solutions that are applicable to a broad range of applications ranging from servers and networking to consumer and mobile. Due to the often complex nature of implementing our technologies, we provide engineering services under certain of these licenses to help our customers successfully integrate our technology solutions into their semiconductor and system products. Licensees may also receive, in addition to their license agreements, patent licenses as necessary to implement the technology in their products with specific rights and restrictions to the applicable patents elaborated in their individual contracts. Our solutions are designed into systems bought by OEMs. We license both directly to ASIC design houses and semiconductor foundries that, in turn, sell to OEMs, or to OEMs directly.

Chip Sets

In the second half of 2016, we began to ship our first chips as a result of our acquisition of the Memory Interconnect Business. Currently, we offer DDR2, DDR3 and DDR4 chipsets for RDIMM and LRDIMM server modules that support the data center and enterprise server infrastructure markets.

data-intensive work loads.
We sell our semiconductor productsmemory interface chips directly and indirectly to module manufacturers and OEMs worldwide through multiple channels, including our direct sales force and distributors. We operate direct sales offices in the United States, Japan, Korea, Taiwan and China, and the United States andwhere we employ sales personnel that coverwho serve our direct customers and manage our channel partners.

We operate a fabless business model and use third-party foundries and assembly and test manufacturing contractors to manufacture,fabricate, assemble and test our semiconductor products.memory interface Chips. We also inspect and test parts in our U.S. basedUS-based facilities. This outsourced manufacturing approach allows us to focus our investment and resources on the research, development, design, sale and marketing of our products. Outsourcing also allows us the flexibility needed to respond to new market opportunities, simplifies our operations and significantly reduces our capital requirements.

Silicon IP
Rambus’ Silicon IP business offers both Interface and Security IP solutions. Our Interface IP solutions feature both high-speed memory and chip-to-chip interconnect technologies. With the acquisition of Northwest Logic in August of 2019, Rambus now offers a complementary portfolio of physical interface (PHY) and companion digital controller IPs to create a one-stop-shop for SoC designers. These silicon-proven solutions are critical to high performance data center, networking, AI, Machine

Security challenges are increasingly prevalent in a multitudeLearning (ML) and automotive applications because they enable and optimize the transfer of industries,data between chips and electronic devices. The chip-to-chip IP portfolio is comprised of industry-standard interface solutions including high-growth sectors such28G, 32G, 56G and 112G SerDes, as mobilewell as the recently announced PCIe 5.0 offering. Rambus’ leading-edge memory Interface solutions include HBM Gen2 and the world’s fastest, silicon-proven GDDR6 solution, capable of running at data rates up to 18 Gbps.
The Rambus Security IP solutions include secure cores, protocols and chip provisioning technologies. Following the acquisition of the Secure Silicon IP and Protocols business from Verimatrix in December 2019, Rambus now offers the industry’s most comprehensive portfolio of silicon-proven Security IP and chip provisioning solutions. With the growing threat environment, posed by malicious actors, we believe it is imperative to protect complex electronic systems at their silicon foundation with hardware-based security IP solutions, including crypto cores, hardware roots of trust, and high-speed protocol engines. As a result, our hardware-based, embedded security solutions are mission-critical for data center, providing a variety of opportunities for our security technologiesAI, networking, IoT, automotive and services. We believe robust security starts with the design of the SoC and continues through the manufacturing supply chain to end-usergovernment applications. In line with this thinking, RSD offers a suiteaddition to augmenting the portfolio through acquisitions, Rambus organically expanded its family of products and services from DPA countermeasures andfully-programmable root of trust cores to offer tailored configurations that address the specific security needs of our CryptoManager™ solution, mobile paymentsvarious target markets leading to design wins with tier-1 cloud and smart ticketing.AI SoC providers.

Architecture Licenses
DPA CountermeasuresRambus patented inventions are foundational to the semiconductor industry and Coreslicenses of our portfolio to our customers represent a significant portion of our revenue. The Company is committed to continuing to innovate and invent, thereby advancing semiconductor technology. With a broad worldwide portfolio of patents covering memory architecture, high-speed serial links, and security, we enhance our value and relevance in our target markets and create a platform for investment in product development.


We own aOur Architecture Licenses enable our customers to use specified portions of our portfolio of patented inventions in the customer’s own digital electronics products, systems or services. These licenses may also define the specific field of use where our customers may use or employ our inventions in their products. License agreements are structured with fixed or variable, or a hybrid of fixed and technology solutions that are needed for creating secure tamper-resistant electronic devicesvariable royalty payments over certain periods ranging up to ten years. Leading consumer product, semiconductor and systems. These patented DPA countermeasures are critical in protecting devices against side channel attackssystem companies such as differential power analysis, which involve monitoring the variationsAMD, Broadcom, Cisco, Freescale, Fujitsu, GE, IBM, Intel, Micron, Nanya, NVIDIA, Panasonic, Qualcomm, Renesas, Samsung, SK hynix, STMicroelectronics, Toshiba, Western Digital, Winbond and Xilinx have licensed our patents for use in power consumption or electromagnetic emissions of a device. In addition, our hardware-based cores provide a robust hardware-based solution to protect electronics systems from side-channel attacks, counterfeiting, piracy, and other forms of attack.

For DPA countermeasures, our business model is to provide a combination of patent licenses, technology, consulting services (training, evaluation, and design), and test equipment as well as DPA resistant cores and software libraries. We are recognized worldwide for our expertise in this area, and our strategy is to strengthen our offering beyond stand-alone patent licensing. We discovered the existence of SPA and DPA vulnerabilities in the 1990s, and patented the fundamental techniques for preventing against this method of attack. DPA protections are a critical security ingredient in tamper-resistant products, and are important or required for a broad range of applications and devices (including smart cards, mobile devices, FPGAs, government/defense applications, consumer set-top boxes, postage meters and security tokens).

In addition to the DPA countermeasures portfolio, we have developed technologies, expertise, advanced designs, and development tools for building highly secure cryptographic semiconductor cores. We have successfully deployed our semiconductor cores in two primary application areas where effective security is valued and paid for by customers: content protection and anti-counterfeiting.

CryptoManager

As connected products, including mobile phones and IoT devices, have a fundamental need for security, a robust security system is critical. Robust security starts with the design of the SoC and continues with the manufacturing supply chain. The Rambus CryptoManager solution brings revolutionary security improvements to the semiconductor chips and supply chains that enable our mobile world.

The CryptoManager platform provides chip and device companies with an advanced hardware root-of-trust for their SoCs, as well as an Infrastructure Suite for end-to-end security throughout the SoC design and manufacturing process. The CryptoManager platform has been developed with a services-based architecture that enables a secure, two-way communication channel across the manufacturing stages. This fully integrated solution is built on a foundation that simplifies, automates, and reduces costs for global enterprise IT, manufacturing, and operations functions. The platform is designed to support the enablement of in-field provisioning and downstream services, such as media, ticketing and mobile payments.

Mobile Payments

NFC-based mobile payments offer many advantages to consumers, retailers and financial institutions alike. For consumers, mobile wallets provide a convenient, “tap and go” frictionless commerce experience, seamlessly integrating credit cards, loyalty points and gift cards, while leveraging enhanced security features like multi-factor authentication and biometrics. For retailers, mobile wallets offer businesses the ability to engage users with an immersive, in-app experience that bridges the gap from digital to physical with profile-based shopping to offer customized recommendations and coupons to customers. Finally for banks, mobile wallets enhance protection from fraud and greater customer engagement and loyalty.

Our technology adapts to any mobile payments ecosystem - whether card credentials are stored on the device or in the cloud using host card emulation - and ensures security through tokenization. With our software, customers can fulfill the role of a token service provider, securing transactions by removing vulnerable card data from the payment network. Our mobile payment solutions are primarily offered to financial institutions through software license agreements.

Smart Ticketing

Smart ticketing is changing the way people travel by bringing greater convenience and security to travelers and transport operators alike. Through the use of smart cards and smart phones, travelers store their tickets electronically, eliminating the need for traditional paper tickets and enabling users to simply tap their smart card or device on a gate or validator to access their travel. Our smart ticketing technology combines back-office processing and analytics systems with web portals, mobile applications and smart cards to deliver comprehensive solutions to transport operators and local authorities. Data analytics enable improved profitability and optimization of smart transport schemes through access to real-world travel data, with easy management of transaction data to ensure accurate reimbursements. ITSO certified and interoperable with existing transport providers, our smart ticketing solutions are easy to integrate across multiple modes of travel, simplifying customer journeys at

lower cost. Currently, our smart ticketing solutions are primarily offered to public transit authorities in the United Kingdom and we are working to expand our offerings into the broader European Union.

Emerging Solutions

ESD encompasses our long-term research and development efforts in emerging technologies, including our lensless smart sensor and smart data acceleration research programs as well as next-generation memory solutions and cryogenic computing. ESD programs are generally at the research and pre-commercial stages and may involve collaboration with government entities, universities and industry partners.

Lighting

The continued adoption of LED as a bright, reliable and energy-efficient light source creates significant market opportunities in the field of general lighting. We have pioneered a light guide-based design that enables a new level of styling, efficiency and control for LED lighting. Our innovations combine our TruEdge™ LED Coupling (maximizing the amount of light emitted from the LED to a light guide) with our MicroLens® optics (tiny 3D features that control how light is emitted from a light guide) to create efficient and cost-effective fixtures. Our light guides are available as off-the-shelf or customized designs that are optimized to specific customer and application requirements by varying the size, shape and density of the MicroLens optics. Manufactured by our global lighting partners or at our state-of-the-art facility in Brecksville, Ohio, our light guides can support both flat and curved designs in a broad range of high volume lighting applications. In addition, complete fixture prototype designs that combine our optical innovations, design engineering and manufacturing support services are also available to lighting system companies and fixture manufacturers worldwide.

own products.
Competition

Our industries areThe semiconductor industry is intensely competitive and have been impactedis characterized by rapid technological change, short product life cycles, cyclical market patterns, price erosion, increasing foreign and domestic competition and market consolidation. We believeRambus competes with product offerings from various companies depending upon the principal competitionparticular Rambus product line. In the market for memory interface Chips, we compete with international semiconductor companies including IDT, now part of Renesas, and Montage Technology. In the Silicon IP market, Rambus competes with the in-house design teams at our technologies may come from our prospectivepotential customers, some of whom are evaluatingas well as with third party IP suppliers such as Arm, Cadence and developing products based on technologies that they contend or may contend will not require a license from us. SomeSynopsys. Many of our competitors use a system-level design approach similar to ours, including activities such as board and package design, power and signal integrity analysis, and thermal management. Many of these companies are larger and may have better access to financial, technical, sales and othermarketing resources than we possess.

To the extent that alternativesalternative technologies, which might provide comparable system performance at lower or similar cost to our patented technologies, or are perceived to require the payment of no or lower fees or royalties, or to the extent other factors influence the industry, our customers and prospective customers may adopt and promote such alternative technologies. Even to the extent we determine that such alternative technologies infringe our patents, there can be no assurance that we would be able to negotiate agreements that would result in royalties being paid to us without litigation, which could be costly and the results of which would be uncertain. InAs in the past, litigation has been and in the future may be required to enforce and protect our intellectual property rights, as well as the substantial investments undertaken to research and develop our innovations and technologies.

Research, Development and Employees

Building upon our foundation of core semiconductor technologies, we aligned our research priorities to focus on innovation and patent development in order to enhance the value of our patent portfolio and differentiate our product offerings in the market. Key to our efforts is continuing to hire and retain world-class inventors, scientists and engineers to lead the development and deployment of inventions and technology solutions for our intended markets.
Our growth strategy will be substantially dependent onTo foster our ability to develop key innovations that meet the future needs of a dynamic market. To this end, we continue to invest substantial funds in research and development and haveefforts, we assembled a team of highly skilled inventors, engineers and scientists whose activities are focused on continually developing new innovations within our chosen technology fields.fields, and thereby securing the intellectual property rights and legal protections for these ground-breaking inventions. Using this foundation of innovations,innovation, our technical teams develop new semiconductor solutions that enable increased performance, greater power efficiency and increased levels of security, as well as other improvements and benefits. Our solution design and development process is a multi-disciplinary effort requiring expertise in multiple fields across all of our operational units.


As of December 31, 2016,2019, we had approximately 540480 employees in our engineering departments, representing approximately 70% of our total number of 767685 employees. None of our employees are covered by collective bargaining agreements. As noted, we believe our future success is dependent on our continued ability to identify, attract, motivate and retain qualified personnel. In order to attract qualified employees, we have created ana work environment and culture that encourages, fosters and supports research, development and innovation in breakthrough technologies with significant opportunities for broad industry adoption. To date, we believe we have been successful in recruiting qualified employees and that we have a good relationship with our employees.



A significant number of our scientists and engineers spend all or a portion of their time on research and development. For the years ended December 31, 2016, 20152019, 2018 and 2014,2017, research and development expenses were $129.8$156.8 million, $111.1$158.3 million and $110.0$149.1 million, respectively. We expect to continue to invest substantial funds in research and development activities. In addition, because our customer agreements often call for us to provide engineering support, a portion of our total engineering costs are allocated to the cost of contract and other revenue.

Intellectual Property

We maintain and support an active program to protect our intellectual property, primarily through the filing of patent applications and the defense of issued patents against potential infringement. As of December 31, 2016,2019, our technologies are covered by 1,9892,339 U.S. and foreign patents, having expiration dates ranging from 20172020 to 2038. Additionally, we have 646589 patent applications pending. Some of the patents and pending patent applications are derived from a common parent patent application or are foreign counterpart patent applications. We believe our patented innovations provide our customers with the abilitylegal rights and licenses to use our inventions to achieve improved performance, lower risk, greater cost-effectiveness and other technological benefits in their own products and services.

We intend to continue our innovation efforts and allocate significant investment in our intellectual property development programs.
We have a program to file applications for and obtain patents in the United States and in selected foreign countries where we believe filing for such protection is appropriate and would further our overall business strategy and objectives. In some instances, obtaining appropriate levels of protection may involve prosecuting continuation and counterpart patent applications based on a common parent application. In addition, we attempt to protect our trade secrets and other proprietary information through agreements with current and prospective customers, and confidentiality agreements with employees and consultants and other security measures. We also rely on copyright, trademarks and trade secret laws to protect our intellectual property.property and other proprietary assets.

Backlog
Our sales of Memory Interface Chips are generally made pursuant to short-term purchase orders. These purchase orders are made without deposits and may be, and often are, rescheduled, canceled or modified on relatively short notice, without substantial penalty. Therefore, we believe that purchase orders or backlog are not necessarily a reliable indicator of our future product sales.
Corporate and Other Information

Rambus Inc. was founded in 1990 and reincorporated in Delaware in March 1997. Our principal executive offices are located at 1050 Enterprise Way, Suite 700, Sunnyvale, California. Our website is www.rambus.com. The inclusion of our website address in this report does not include or incorporate by reference into this report any information on our website. You can obtain copies of our Forms 10-K, 10-Q, 8-K, and other filings with the SEC, and all amendments to these filings, free of charge, from our website as soon as reasonably practicable following our filing of any of these reports with the SEC. In addition, you may read and copy any material we file with the SEC at the SEC’s Public Reference Room at 100 F Street NE, Room 1580, Washington, D.C. 20549. You may obtain information on the operation of the Public Reference Room by calling the SEC at 1-800-SEC-0330. The SEC also maintains a website that contains reports, proxy, and information statements, and other information regarding registrants that file electronically with the SEC at www.sec.gov.

www.sec.gov.
Information concerning our revenue, results of operations and revenue by geographic area is set forth in Item 6, “Selected Financial Data,” in Item 7, “Management’s Discussion and Analysis of Financial Condition and Results of Operations,” and in Note 6,7, “Segments and Major Customers,” of Notes to Consolidated Financial Statements of this Form 10-K, all of which are incorporated herein by reference. Information concerning identifiable assets and segment reporting is also set forth in Note 6,7, “Segments and Major Customers,” of Notes to Consolidated Financial Statements of this Form 10-K. Information on customers that comprise 10% or more of our consolidated revenue and risks attendant to our foreign operations is set forth below in Item 1A, “Risk Factors .”Factors.”


6



Our Named Executive Officers
Information regarding our named executive officers and their ages and positions as of February 26, 2020, is contained in the table below. Our named executive officers are appointed by, and serve at the discretion of, our Board of Directors. There is no family relationship between any of our named executive officers.
NameAgePosition and Business Experience
Luc Seraphin56
Mr. Seraphin is President & Chief Executive Officer. With over 20 years of experience managing global businesses, Mr. Seraphin brings the overall vision and leadership necessary to drive future growth for the company. Prior to this role, Mr. Seraphin was the senior vice president and general manager of the Memory and Interface Division, leading the development of the company’s innovative memory architectures and high-speed serial link solutions. Mr. Seraphin also served as the senior vice president of Worldwide Sales and Operations where he oversaw sales, business development, customer support and operations across the various business units within Rambus.
Mr. Seraphin started his career as a field application engineer at NEC and later joined AT&T Bell Labs, which became Lucent Technologies and Agere Systems (now Broadcom Inc.). During his 18 years at Agere, Mr. Seraphin held several senior positions in sales, marketing and general management, culminating in his last position as executive vice president and general manager of the Wireless Business Unit. Following this, Mr. Seraphin held the position of general manager of a GPS startup company in Switzerland and was vice president of Worldwide Sales and Support at Sequans Communications. During his career, Mr. Seraphin has advised and supported companies in both the product and IP markets.
Mr. Seraphin holds a bachelor’s degree in Mathematics and Physics and a master’s degree in Electrical Engineering from Ecole Superieure de Chimie, Physique, Electronique, based in Lyon, France where he majored in Computer Architecture. Mr. Seraphin also holds an MBA from the University of Hartford and has completed the senior executive program of Columbia University.
Rahul Mathur46Senior Vice President, Finance and Chief Financial Officer. Mr. Mathur joined us in his current position in October 2016. Prior to joining us, Mr. Mathur served as senior vice president of finance at Cypress Semiconductor Corp., a provider of embedded memory, microcontroller, and analog semiconductor system solutions, from March 2015 to September 2016, where he was responsible for financial planning and investor relations. From August 2012 to March 2015, Mr. Mathur served as vice president of finance at Spansion, Inc. (later acquired by Cypress Semiconductor Corp.). Mr. Mathur served as vice president of finance at Picaboo Corporation from January 2012 to August 2012 and vice president of finance at CDNetworks Inc. from January 2011 to December 2011. Prior to January 2011, Mr. Mathur held senior finance positions at Telesis Technologies, Inc., NetSuite Inc. and KLA Corporation. Mr. Mathur holds a Bachelor of Arts in applied mathematics from Dartmouth College and an M.B.A. from the Wharton School of Business at the University of Pennsylvania.
Jae Kim49Senior Vice President, General Counsel and Secretary. Mr. Kim has served as the senior vice president, general counsel and secretary since February 2013 and as our vice president, corporate legal since July 2010. Prior to his tenure at Rambus, Mr. Kim held senior legal positions at Aricent Inc., a privately-held communications technology company and Electronics for Imaging Inc., a digital printing technology company. Mr. Kim has also had significant experience in private practice with the law firm of Wilson Sonsini Goodrich & Rosati, P.C., where he advised high technology and emerging growth companies on mergers and acquisitions, private financings, public offerings, securities compliance, public company reporting and corporate governance. Mr. Kim began his legal career as an attorney with the United States Securities and Exchange Commission, Division of Corporation Finance, in Washington, D.C. Mr. Kim is a member of both the California State Bar and New York State Bar, and received a J.D. from the American University, Washington College of Law, and his bachelor’s degree from Boston University.
Sean Fan54Senior Vice President, Chief Operating Office. Mr. Fan has served as the senior vice president, chief operating office since August 2019.  Prior to Rambus from March 2019 to June 2019 he served as Vice President and General Manager at Renesas Electronics Corporation, responsible for the datacenter business unit, a premier supplier of advanced semiconductor solutions. Prior to his role at Renesas, Mr. Fan was Senior Vice President and Corporate General Manager of the Computing and Communications Group at Integrated Device Technology, Inc. (“IDT”), a leading supplier of analog mixed-signal products including sensors, connectivity and wireless power, from May 2017 until March 2019 when IDT was acquired by Renesas Electronics Corporation. Mr. Fan joined IDT in 1999 and held various management roles at IDT, including Vice President and General Manager of the Computing and Communications Division, Vice President and General Manager of the Interface Connectivity Division, Vice President of China Operations, Vice President and General Manager of the Memory Interface Division, General Manager of Standard Product Operations, and Senior Director of Silicon Timing Solutions. Prior to joining IDT, Mr. Fan served in various engineering and management roles with Lucent Microelectronics, Mitel Semiconductor, and the National Lab of Telecom Research in China.

Item 1A.Risk Factors
RISK FACTORS
Because of the following factors, as well as other variables affecting our operating results, past financial performance may not be a reliable indicator of future performance, and historical trends should not be used to anticipate results or trends in future periods. See also “Note Regarding Forward-Looking Statements” at the beginning of this report.

Risks Associated With Our Business, Industry and Market Conditions
The success of our business depends on sustaining or growing our licensing revenue and the failure to achieve such revenue would lead to a material decline in our results of operations.

Our revenue consists mainlylargely of patent and technology license fees paid for access to our patents, developedpatented technologies, existing technology and other development and support services providedwe provide to our customers. Our ability to secure and renew the licenses from which our revenues are derived depends on our customers adopting our technology and using it in the products they sell. Once secured, license revenue may be negatively affected by factors within and outside our control, including reductions in our customers’ sales prices, sales volumes, our failure to timely complete engineering deliverables, and the actual terms of such licenses.licenses themselves. In addition, our licensing cycle for new licensees as well as for renewals for existing licensees is lengthy, costly and unpredictable without any degree of certainty.unpredictable. We cannot provide any assurance that we will be successful in signing new license agreements or renewing existing license agreements on equal or favorable terms or at all. If we do not achieve our revenue goals, our results of operations could decline.
We have traditionally operated in, and may enter other, industries that are highly cyclical and competitive.
Our target customers are companies that develop and market high volume business and consumer products in semiconductors, computing, data centers, networks, tablets, handheld devices, mobile applications, gaming and graphics, high-definition televisions, general lighting, cryptography and data security. The electronics industry is intensely competitive and has been impacted by rapid technological change, short product life cycles, cyclical market patterns, price erosion and increasing foreign and domestic competition. We are subject to many risks beyond our control that influence whether or not we are successful in winning target customers or retaining existing customers, including, primarily, competition in a particular industry, market acceptance of such customers' products and the financial resources of such customers. In particular, DRAM manufacturers, which make up a significant part of our revenue, are prone to significant business cycles and have suffered material losses and other adverse effects to their businesses, leading to industry consolidation from time-to-time that may result in loss of revenues under our existing license agreements or loss of target customers. As a result of ongoing competition in the industries in which we operate and volatility in various economies around the world, we may achieve a reduced number of licenses or may experience tightening of customers' operating budgets, difficulty or inability of our customers to pay our licensing fees, lengthening of the approval process for new licenses and consolidation among our customers. All of these factors may adversely affect the demand for our technology and may cause us to experience substantial fluctuations in our operating results.
We face competition from semiconductor and digital electronics products and systems companies, other semiconductor intellectual property companies that provide security cores and non-edge lit LED lighting options that are available to the market. We believe the principal competition for our technologies may come from our prospective customers, some of whom are evaluating and developing products based on technologies that they contend or may contend will not require a license from us. Some of our competitors use a system-level design approach similar to ours, including activities such as board and package design, power and signal integrity analysis, and thermal management. Many of these companies are larger and may have better access to financial, technical and other resources than we possess.
To the extent that alternatives might provide comparable system performance at lower or similar cost to our technologies, or are perceived to require the payment of no or lower royalties, or to the extent other factors influence the industry, our customers and prospective customers may adopt and promote alternative technologies. Even to the extent we determine that such alternative technologies infringe our patents, there can be no assurance that we would be able to negotiate agreements that would result in royalties being paid to us without litigation, which could be costly and the results of which would be uncertain.
In addition, our expansion into new markets subjects us to additional risks. We may have limited or no experience in new products and markets, including our CryptoManager platform and new offerings that have resulted from our acquisition of SCS in the mobile payment and smart ticketing solution spaces, and our acquisitions of the assets of the Snowbush IP group and the Memory Interconnect Business, and our customers may not adopt our new offerings. These and other new offerings may present new and difficult challenges, which could negatively affect our operating results.


We may have to invest more resources in research and development than anticipated, which could increase our operating expenses and negatively impact our operating results.

If new competitors, technological advances by existing competitors, and/or development of new technologies or other competitive factors require us to invest significantly greater resources than anticipated in our research and development efforts, our operating expenses could increase. If we are required to invest significantly greater resources than anticipated in research and development efforts without an increase in revenue, our operating results would decline. We expect these expenses to increase in the foreseeable future as our technology development efforts continue.
Our revenue is concentrated in a few customers, and if we lose any of these customers through contract terminations or acquisitions, our revenue may decrease substantially.
We have a high degree of revenue concentration. Our top five customers represented approximately 63% and 65% of our revenues for the years ended December 31, 2016 and 2015, respectively. For both of the years ended December 31, 2016 and 2015, revenues from Micron, Samsung and SK hynix each accounted for 10% or more of our total revenue in each year. We extended our license agreement with Samsung in December 2013, and we expect Samsung to continue to account for a significant portion of our licensing revenue. We also entered into settlement agreements with each of SK hynix and Micron (which included Elpida, which Micron had acquired in July 2013) in June 2013 and December 2013, respectively. In June 2015, we also extended our license agreement with SK hynix. As a result of the renewal and such settlements, we expect each of Samsung, SK hynix and Micron to account for a significant portion of our licensing revenue in the future. We expect to continue to experience significant revenue concentration for the foreseeable future.
In addition, our license agreements are complex and some contain terms that require us to provide certain customers with the lowest royalty rate that we provide to other customers for similar technologies, volumes and schedules. These clauses may limit our ability to effectively price differently among our customers, to respond quickly to market forces, or otherwise to compete on the basis of price. These clauses may also require us to reduce royalties payable by existing customers when we enter into or amend agreements with other customers. Any adjustment that reduces royalties from current customers or licensees may have a material adverse effect on our operating results and financial condition.
We continue to negotiate with customers and prospective customers to enter into license agreements. Any future agreement may trigger our obligation to offer comparable terms or modifications to agreements with our existing customers, which may be less favorable to us than the existing license terms. We expect licensing fees will continue to vary based on our success in renewing existing license agreements and adding new customers, as well as the level of variation in our customers' reported shipment volumes, sales price and mix, offset in part by the proportion of customer payments that are fixed. In particular, under our license agreement with Samsung, the license fees payable by Samsung are subject to certain adjustments and conditions, and we therefore cannot provide assurances that the revenues generated by this license will not decline in the future. In addition, some of our material license agreements may contain rights by the customer to terminate for convenience, or upon certain other events, such as change of control, material breach, insolvency or bankruptcy proceedings. If we are unsuccessful in entering into license agreements with new customers or renewing license agreements with existing customers, on favorable terms or at all, or if they are terminated, our results of operations may decline significantly.
Our business and operations could suffer in the event of security breaches.
Attempts by others to gain unauthorized access to our information technology systems are becoming more sophisticated. These attempts, which might be related to industrial or other espionage, include covertly introducing malware to our computers and networks and impersonating authorized users, among others. We seek to detect and investigate all security incidents and to prevent their recurrence, but in some cases, we might be unaware of an incident or its magnitude and effects. While we have not identified any material incidents of unauthorized access to date, the theft, unauthorized use or publication of our intellectual property and/or confidential business information could harm our competitive position and reputation, reduce the value of our investment in research and development and other strategic initiatives or otherwise adversely affect our business. To the extent that any future security breach results in inappropriate disclosure of our customers' confidential information, we may incur liability.
Failures in our products and services or in the products of our customers, including those resulting from security vulnerabilities, defects, bugs or errors, could harm our business.
Our products and services are highly technical and complex, and among our various businesses our products and services are crucial to providing security, payment and other critical functions for our customers’ operations. Our products and services have from time to time contained and may in the future contain undetected errors, bugs defects or other security vulnerabilities. Some errors in our products and services may only be discovered after a product or service has been deployed and used by customers, and may in some cases only be detected under certain circumstances or after extended use. In addition, because the

techniques used by hackers to access or sabotage our products and services and other technologies change and evolve frequently and generally are not recognized until launched against a target, we may be unable to anticipate, detect or prevent these techniques and may not address them in our data security technologies. Any errors, bugs, defects or security vulnerabilities discovered in our solutions after commercial release could adversely affect our revenue, our customer relationships and the market's perception of our products and services. We may not be able to correct any errors, bugs, defects, security flaws or vulnerabilities promptly, or at all. Any breaches, defects, errors or vulnerabilities in our products and services could result in:

expenditure of significant financial and research and development resources in efforts to analyze, correct, eliminate or work around breaches, errors, bugs or defects or to address and eliminate vulnerabilities;
financial liability to customers for breach of certain contract provisions, including indemnification obligations;
loss of existing or potential customers;
delayed or lost revenue;
delay or failure to attain market acceptance;
negative publicity, which would harm our reputation; and
litigation, regulatory inquiries or investigations that would be costly and harm our reputation.
Some of our revenue is subject to the pricing policies of our customers over whom we have no control.
We have no control over our customers' pricing of their products and there can be no assurance that licensed products will be competitively priced or will sell in significant volumes. Any premium charged by our customers in the price of memory and controller chips or other products over alternatives must be reasonable. If the benefits of our technology do not match the price premium charged by our customers, the resulting decline in sales of products incorporating our technology could harm our operating results.
Our licensing cycle is lengthy and costly, and our marketing and licensing efforts may be unsuccessful.

The process of persuading customers to adopt and license our chipChip interface, lighting, data security,Security IP, and other technologies can be lengthy. Even if successful, there can be no assurance that our technologies will be used in a product that is ultimately brought to market, achieves commercial acceptance or results in significant royalties to us. We generally incur significant marketing and sales expenses prior to entering into our license agreements, generating a license fee and establishing a royalty stream from each customer. The length of time it takes to establish a new licensing relationship can take many months or even years. We may incur costs in any particular period before any associated revenue stream begins, if at all. If our marketing and sales efforts are very lengthy or unsuccessful, then we may face a material adverse effect on our business and results of operations as a result of failure to obtain or an undue delay in obtaining royalties.

Some of our license agreements may convert to fully paid-up licenses at the expiration of their terms, or upon certain milestones, and we may not receive royalties after that time.

From time to time, we enter into license agreements that automatically convert to fully paid-up licenses upon expiration or upon reaching certain milestones. We may not receive further royalties from customers for any licensed technology under those agreements if they convert to fully paid-up licenses because such customers will be entitled to continue using some, if not all, of the relevant intellectual property or technology under the terms of the license agreements without further payment, even if relevant patents or technologies are still in effect. If we cannot find another source of royalties to replace the royalties from these license agreements converting to fully paid-up licenses, our results of operations following such conversion could be adversely affected.

Future revenue is difficult to predict for several reasons, and our failure to predict revenue accurately may result in our stock price declining.

Our lengthy license negotiation cycles could make our future revenue difficult to predict because we may not be successful in entering into or renewing licenses with our customers on our anticipated timelines. As we commercially launch each of our products, the sales volume of and resulting revenue from such products in any given period will be difficult to predict.

In addition, while some of our license agreements provide for fixed, quarterly royalty payments, many of our license agreements provide for volume-based royalties and may also be subject to caps on royalties in a given period. The sales volume and prices of our customers'customers’ products in any given period can be difficult to predict. In addition, we began applying the new revenue recognition standard (ASC 606) during the first quarter of 2018, as required, and we anticipate that our revenue will vary greatly from quarter to quarter. As a result of the foregoing items, our actual results may differ substantially from analyst estimates or our forecasts in any given quarter.
Furthermore,
Also, a portion of our revenue comes from development and support services provided to our customers. Depending upon the nature of the services, a portion of the related revenue may be recognized ratably over the support period, or may be recognized according to contract revenue accounting. Contract revenue accounting may result in deferral of the service fees to the completion of the contract, or may result in the recognition of service fees over the period in which services are performed on a percentage-of-completion basis.

Our revenue is concentrated in a few customers, and if we lose any of these customers through contract terminations or acquisitions, our revenue may decrease substantially.

We have a high degree of revenue concentration. Our top five customers for each reporting period represented approximately 46%, 49% and 55% of our revenue for the years ended December 31, 2019, 2018 and 2017, respectively. For 2019, revenue from Broadcom and SK hynix each accounted for 10% or more of our total revenue. For 2018, revenue from Broadcom and NVIDIA each accounted for 10% or more of our total revenue. For 2017, revenue from Micron, Samsung and SK hynix each accounted for 10% or more of our total revenue. We expect to continue to experience significant revenue concentration for the foreseeable future.

In addition, our license agreements are complex and some contain terms that require us to provide certain customers with the lowest royalty rate that we provide to other customers for similar technologies, volumes and schedules. These clauses may limit our ability to effectively price differently among our customers, to respond quickly to market forces, or otherwise to compete on the basis of price. These clauses may also require us to reduce royalties payable by existing customers when we enter into or amend agreements with other customers. Any adjustment that reduces royalties from current customers or licensees may have a material adverse effect on our operating results and financial condition.

We continue to negotiate with customers and prospective customers to enter into license agreements. Any future agreement may trigger our obligation to offer comparable terms or modifications to agreements with our existing customers, which may be less favorable to us than the existing license terms. We expect licensing fees will continue to vary based on our success in renewing existing license agreements and adding new customers, as well as the level of variation in our customers’ reported shipment volumes, sales price and mix, offset in part by the proportion of customer payments that are fixed. In particular, under our license agreement with Samsung, the license fees payable by Samsung are subject to certain adjustments and conditions, and we therefore cannot provide assurances that the revenues generated by this license will not decline in the future. In addition, some of our material license agreements may contain rights by the customer to terminate for convenience, or upon certain other events, such as change of control, material breach, insolvency or bankruptcy proceedings. If we are unsuccessful in entering into license agreements with new customers or renewing license agreements with existing customers, on favorable terms or at all, or if they are terminated, our results of operations may decline significantly.

Some of our revenue is subject to the pricing policies of our customers over which we have no control.

We have no control over our customers’ pricing of their products and there can be no assurance that licensed products will be competitively priced or will sell in significant volumes. Any premium charged by our customers in the price of memory and controller chips or other products over alternatives must be reasonable. If the benefits of our technology do not match the price premium charged by our customers, the resulting decline in sales of products incorporating our technology could harm our operating results.

We have traditionally operated in, and may enter other, industries that are highly cyclical and competitive.

Our target customers are companies that develop and market high volume business and consumer products in semiconductors, computing, data centers, networks, tablets, handheld devices, mobile applications, gaming and graphics, high-definition televisions, cryptography and data security. The electronics industry is intensely competitive and has been impacted by rapid technological change, short product life cycles, cyclical market patterns, price erosion and increasing foreign and domestic competition. We are subject to many risks beyond our control that influence whether or not we are successful in winning target customers or retaining existing customers, including, primarily, competition in a particular industry, market acceptance of such customers’ products and the financial resources of such customers. In particular, DRAM manufacturers, which such customers make up a significant part of our revenue, are prone to significant business cycles and have suffered material losses and other adverse effects to their businesses, leading to industry consolidation from time-to-time that may result in loss of revenues under our existing license agreements or loss of target customers. As a result of ongoing competition in the industries in which we operate and volatility in various economies around the world, we may achieve a reduced number of licenses or may experience tightening of customers’ operating budgets, difficulty or inability of our customers to pay our licensing fees, lengthening of the approval process for new licenses and consolidation among our customers. All of these factors may adversely affect the demand for our technology and may cause us to experience substantial fluctuations in our operating results.

We face competition from semiconductor and digital electronics products and systems companies, and other semiconductor intellectual property companies that provide security cores that are available to the market. We believe the principal competition

for our technologies may come from our prospective customers, some of which are evaluating and developing products based on technologies that they contend or may contend will not require a license from us. Some of our competitors use a system-level design approach similar to ours, including activities such as board and package design, power and signal integrity analysis, and thermal management. Many of these companies are larger and may have better access to financial, technical and other resources than we possess.

To the extent that alternative technologies might provide comparable system performance at lower or similar cost to our technologies, or are perceived to require the payment of no or lower royalties, or to the extent other factors influence the industry, our customers and prospective customers may adopt and promote such alternative technologies. Even to the extent we determine that such alternative technologies infringe our patents, there can be no assurance that we would be able to negotiate agreements that would result in royalties being paid to us without litigation, which could be costly and the results of which would be uncertain.

In addition, our expansion into new markets subjects us to additional risks. We may have limited or no experience in new products and markets, and our customers may not adopt our new offerings. These and other new offerings may present new and difficult challenges, which could negatively affect our operating results.

Our customers often require our products to undergo a lengthy and expensive qualification process which does not assure product sales. If we are unsuccessful or delayed in qualifying any of our products with a customer, our business and operating results would suffer.

Prior to purchasing our products, our customers often require that our products undergo extensive qualification processes, which involve testing of our products in the customers’ systems, as well as testing for reliability. This qualification process may continue for several months. However, qualification of a product by a customer does not assure any sales of the product to that customer. Even after successful qualification and sales of a product to a customer, a subsequent revision in third party manufacturing processes may require a new qualification process with our customers, which may result in delays and in our holding excess or obsolete inventory. After our products are qualified, it can take several months or more before the customer commences volume production of components or systems that incorporate our products. Despite these uncertainties, we devote substantial resources, including design, engineering, sales, marketing and management efforts, to qualify our products with customers in anticipation of sales. If we are unsuccessful or delayed in qualifying any of our products with a customer, sales of those products to the customer may be precluded or delayed, which may impede our growth and cause our business to suffer.

We may have to invest more resources in research and development than anticipated, which could increase our operating expenses and negatively impact our operating results.

If new competitors, technological advances by existing competitors, and/or development of new technologies or other competitive factors require us to invest significantly greater resources than anticipated in our research and development efforts, our operating expenses could increase. If we are required to invest significantly greater resources than anticipated in research and development efforts without an increase in revenue, our operating results would decline. We expect these expenses to increase in the foreseeable future as our technology development efforts continue.

Our business and operations could suffer in the event of security breaches.

Attempts by others to gain unauthorized access to our information technology systems are becoming more sophisticated. These attempts, which might be related to industrial or other espionage, include covertly introducing malware to our computers and networks and impersonating authorized users, among others. We seek to detect and investigate all security incidents and to prevent their recurrence, but in some cases, we might be unaware of an incident or its magnitude and effects. While we have not identified any material incidents of unauthorized access to date, the theft, unauthorized use or publication of our intellectual property and/or confidential business information could harm our competitive position and reputation, reduce the value of our investment in research and development and other strategic initiatives or otherwise adversely affect our business. To the extent that any future security breach results in inappropriate disclosure of our customers’ confidential information or any personally-identifiable information of our employees, we may incur liability.

Failures in our products and services or in the products of our customers, including those resulting from security vulnerabilities, defects, bugs or errors, could harm our business.

Our products and services are highly technical and complex, and among our various businesses our products and services are crucial to providing security and other critical functions for our customers’ operations. Our products and services have from

time to time contained and may in the future contain undetected errors, bugs, defects or other security vulnerabilities. Some errors in our products and services may only be discovered after a product or service has been deployed and used by customers, and may in some cases only be detected under certain circumstances or after extended use. In addition, because the techniques used by hackers to access or sabotage our products and services and other technologies change and evolve frequently and generally are not recognized until launched against a target, we may be unable to anticipate, detect or prevent these techniques and may not address them in our data security technologies. Any errors, bugs, defects or security vulnerabilities discovered in our solutions after commercial release could adversely affect our revenue, our customer relationships and the market’s perception of our products and services. We may not be successfulable to correct any errors, bugs, defects, security flaws or vulnerabilities promptly, or at all. Any breaches, defects, errors or vulnerabilities in entering into new markets,our products and our new product offerings, such as our acquisitionsservices could result in:

expenditure of SCS, the assetssignificant financial and research and development resources in efforts to analyze, correct, eliminate or work around breaches, errors, bugs or defects or to address and eliminate vulnerabilities;
financial liability to customers for breach of the Snowbush IP group and the Memory Interconnect Business, our CryptoManager platform and new offerings in the mobile credential and smart card solution spaces, may not be adopted by our customerscertain contract provisions, including indemnification obligations;
loss of existing or potential customers. In addition, once we commercially launchcustomers;
product shipment restrictions or prohibitions to certain customers;
delayed or lost revenue;
delay or failure to attain market acceptance;
negative publicity, which would harm our products, the sales volume ofreputation; and resulting revenue from such products in any given period will
litigation, regulatory inquiries or investigations that would be difficult to predict.costly and harm our reputation.


We may fail to meet our publicly announced guidance or other expectations about our business, which would likely cause our stock price to decline.


We provide guidance regarding our expected financial and business performance including our anticipated future revenues, operating expenses and operating expenses. other financial and operation metrics. We enhanced our guidance following implementation of Accounting Standards Update (ASU) No. 2014-09, Revenue from Contracts with Customers in Accounting Standards Codification (ASC) Topic 606 (“ASC 606”, “the New Revenue Standard”) in the first quarter of 2018.

Correctly identifying the key factors affecting business conditions and predicting future events is an inherently an uncertain process.
Such Any guidance that we provide may not always be accurate, or may vary from actual results, due to our inability to meet our assumptionscorrectly identify and the impact on our financial performance that could occur as a result of the variousquantify risks and uncertainties to our business as set forth in these risk factors.and to quantify their impact on our financial performance. We offer no assurance that such guidance will ultimately be accurate, and investors should treat any such guidance with appropriate caution. If we fail to meet our guidance or if we find it necessary to revise such guidance, even if such failure or revision is seemingly insignificant, investors and analysts may lose confidence in us and the market value of our common stock could be materially adversely affected.

Changes in accounting principles and guidance could result in unfavorable accounting charges or effects.

We prepare our financial statements in accordance with accounting principles generally accepted in the United States and these principles are subject to interpretation by the SEC and various bodies. A change in these principles or application guidance, or in their interpretations, may have a material effect on our reported results, as well as our processes and related controls, and may retroactively affect previously reported results. For instance, we adopted ASC 842, the New Leasing Standard, effective for us on January 1, 2019, using the alternative transition method and recognized a cumulative-effect adjustment to the opening balance of accumulated deficit on January 1, 2019. We also adopted ASC 606, the New Revenue Standard, effective for us on January 1, 2018, on a modified retrospective basis, with a cumulative-effect adjustment to the opening balance of accumulated deficit on January 1, 2018. The New Revenue Standard materially impacted the timing of revenue recognition for our fixed-fee intellectual property (IP) licensing arrangements (including certain fixed-fee agreements that license our existing IP portfolio as well as IP added to our portfolio during the license term) as a majority of such revenue would be recognized at inception of the license term, as opposed to over time as is the case under prior U.S. GAAP, and we are required to compute and recognize interest income over time for certain licensing arrangements as control over the IP generally transfers significantly in advance of cash being received from customers. The impact of the adoption of the New Revenue Standard did not have a material impact on our other revenue streams. We have also enhanced the form and content of some of our guidance metrics that we provide following implementation of the New Revenue Standard. We expect that any change to current revenue recognition practices may significantly increase volatility in our quarterly revenue, financial results and trends, and may impact our stock price.

We have in the past made and may in the future make acquisitions or enter into mergers, strategic investments, sales of assets, divestitures or other arrangements that may not produce expected operating and financial results.

From time to time, we engage in acquisitions, strategic transactions, and strategic investments, such as our acquisitions of SCS, the assets of the Snowbush IP groupdivestitures and the Memory Interconnect Business.potential discussions with respect thereto. Many of our acquisitions or strategic investments entail a high degree of risk, including those involving new areas of technology and such investments may not become liquid for several years after the date of the investment, if at all. Our acquisitions or strategic investments may not provide the advantages that we anticipated or generate the financial returns we expect, including if we are unable to close any pending acquisitions. For example, for any pending or completed acquisitions, we may discover unidentified issues not discovered in due diligence, and we may be subject to regulatory approvals or liabilities that are not covered by indemnification protection or become subject to litigation. Achieving the anticipated benefits of business acquisitions depends in part upon our ability to integrate the acquired businesses in an efficient and effective manner. The integration of companies that have previously operated independently may result in significant challenges, including, among others: retaining key employees; successfully integrating new employees, business systems and technology; retaining customers of the acquired business; minimizing the diversion of management'smanagement’s and other employees’ attention from ongoing business matters; coordinating geographically separate organizations; consolidating research and development operations; and consolidating corporate and administrative infrastructures.

Our strategic investments in new areas of technology may involve significant risks and uncertainties, including distraction of management from current operations, greater than expected liabilities and expenses, inadequate return of capital, and unidentified issues not discovered in due diligence. These investments are inherently risky and may not be successful.

In addition, we may record impairment charges related to our acquisitions or strategic investments. Any losses or impairment charges that we incur related to acquisitions, strategic investments or sales of assets will have a negative impact on our financial results and the market value of our common stock, and we may continue to incur new or additional losses related to acquisitions or strategic investments.

We may have to incur debt or issue equity securities to pay for any future acquisition,acquisitions, which debt could involve restrictive covenants or which equity security issuance could be dilutive to our existing stockholders. We may also use cash to pay for any future acquisitions which will reduce our cash balance.

From time to time, we may also divest certain assets. These divestitures or proposed divestitures may involve the loss of revenue and/or potential customers, and the market for the associated assets wheremay dictate that we sell such assets for less than what we paid. In addition, in connection with any asset sales or divestitures, we may be required to provide certain representations, warranties and covenants to their buyers. While we would seek to ensure the accuracy of such representations and warranties and fulfillment of any ongoing obligations, we may not be completely successful and consequently may be subject to claims by a purchaser of such assets.

A substantial portion of our revenue is derived from sources outside of the United States and this revenue and our business generally are subject to risks related to international operations that are often beyond our control.

For the years ended December 31, 20162019, 2018 and 2015,2017, revenues received from our international customers constituted approximately 64%40%, 44% and 60%58%, respectively, of our total revenue. We expect that future revenue derived from international sources will continue to represent a significant portion of our total revenue.

To the extent that customer sales are not denominated in U.S. dollars, any royalties which are based on a percentage of the customers'customers’ sales that we receive as a result of such sales could be subject to fluctuations in currency exchange rates. In addition, if the effective price of licensed products sold by our foreign customers were to increase as a result of fluctuations in the exchange rate of the relevant currencies, demand for licensed products could fall, which in turn would reduce our royalties. We do not use financial instruments to hedge foreign exchange rate risk.

Trade-related government actions, whether implemented by the US government, China or other countries, that impose barriers or restrictions that would impact our ability to sell or ship products to certain customers may have a negative impact on our financial condition and results of operations. We cannot predict the actions government entities may take in this context and may be unable to quickly offset or effectively react to government actions that restrict our ability to sell to certain customers or in certain jurisdictions. Government actions that affect our customers’ ability to sell products or access critical elements of their supply chains may result in a decreased demand for their products, which may consequently reduce their demand for our products.

We currently have international business operations in the United Kingdom, France and the Netherlands, international design operations in Canada, India Finland and France,Finland, and business development operations in China, Japan, Korea, Singapore and Taiwan. Our international operations and revenue are subject to a variety of risks which are beyond our control, including:

hiring, maintaining and managing a workforce and facilities remotely and under various legal systems, including compliance with local labor and employment laws;
non-compliance with our code of conduct or other corporate policies;
natural disasters, acts of war, terrorism, widespread global pandemics or illness, such as the current Coronavirus (COVID-19), or security breaches;
export controls, tariffs, import and licensing restrictions and other trade barriers;
profits, if any, earned abroad being subject to local tax laws and not being repatriated to the United States or, if repatriation is possible, limited in amount;
adverse tax treatment of revenue from international sources and changes to tax codes, including being subject to foreign tax laws and being liable for paying withholding, income or other taxes in foreign jurisdictions;
unanticipated changes in foreign government laws and regulations;
increased financial accounting and reporting burdens and complexities;
lack of protection of our intellectual property and other contract rights by jurisdictions in which we may do business to the same extent as the laws of the United States;
potential vulnerability to computer system, internet or other systemic attacks, such as denial of service, viruses or other malware which may be caused by criminals, terrorists or other sophisticated organizations;
social, political and economic instability;
geopolitical issues, including changes in diplomatic and trade relationships;relationships, in particular with China; and
cultural differences in the conduct of business both with customers and in conducting business in our international facilities and international sales offices.

We and our customers are subject to many of the risks described above with respect to companies which are located in different countries. There can be no assurance that one or more of the risks associated with our international operations will not result in a material adverse effect on our business, financial condition or results of operations.

Weak global economic conditions may adversely affect demand for the products and services of our customers.

Our operations and performance depend significantly on worldwide economic conditions. UncertaintyFuture uncertainty about global or regional economic and political conditions poses a risk as consumers and businesses may postpone spending in response to tighter credit, negative financial news and declines in income or asset values, which could have a material negative effect on the demand for the products of our customers in the foreseeable future. If our customers experience reduced demand for their products as a result of global or regional economic conditions or otherwise, this could result in reduced royalty revenue and our business and results of operations could be harmed.

If our counterparties are unable to fulfill their financial and other obligations to us, our business and results of operations may be affected adversely.

Any downturn in economic conditions or other business factors could threaten the financial health of our counterparties, including companies with whomwhich we have entered into licensing and/or settlement agreements, and their ability to fulfill their financial and other obligations to us. Such financial pressures on our counterparties may eventually lead to bankruptcy proceedings or other attempts to avoid financial obligations that are due to us. Because bankruptcy courts have the power to modify or cancel contracts of the petitioner which remain subject to future performance and alter or discharge payment obligations related to pre-petition debts, we may receive less than all of the payments that we would otherwise be entitled to receive from any such counterparty as a result of bankruptcy proceedings.

If we are unable to attract and retain qualified personnel, our business and operations could suffer.

Our success is dependent upon our ability to identify, attract, compensate, motivate and retain qualified personnel, especially engineers, senior management and other key personnel. The loss of the services of any key employees could be disruptive to our development efforts, or business relationships and strategy, and could cause our business and operations to suffer.

Recently, we have experienced significant changes in our management team, including in the role of chief executive officer and other senior executives. Our future success depends in large part upon the continued service and enhancement of our

management team and our employees. If there are further changes in management, such changes could be disruptive and could negatively affect our sales, operations, culture, future recruiting efforts and strategic direction. Competition for qualified executives is intense and if we are unable to compensate our key talent appropriately and continue expanding our management team, or successfully integrate new additions to our management team in a manner that enables us to scale our business and operations effectively, our ability to operate effectively and efficiently could be limited or negatively impacted. In addition, changes in key management positions may temporarily affect our financial performance and results of operations as new management becomes familiar with our business, processes and strategy. The loss of any of our key personnel, or our inability to attract, integrate and retain qualified employees, could require us to dedicate significant financial and other resources to such personnel matters, disrupt our operations and seriously harm our operations and business.

We are subject to various government restrictions and regulations, including on the sale of products and services that use encryption technology and those related to privacy and other consumer protection matters.

Various countries have adopted controls, license requirements and restrictions on the export, import and use of products or services that contain encryption technology. In addition, governmental agencies have proposed additional requirements for encryption technology, such as requiring the escrow and governmental recovery of private encryption keys. Restrictions on the sale or distribution of products or services containing encryption technology may impact theour ability of RSD to license its data security technologies to the manufacturers and providers of such products and services in certain markets or may require RSD

us or itsour customers to make changes to the licensed data security technology that is embedded in such products to comply with such restrictions. Government restrictions, or changes to the products or services of RSD'sour customers to comply with such restrictions, could delay or prevent the acceptance and use of such customers'customers’ products and services. In addition, the United States and other countries have imposed export controls that prohibit the export of encryption technology to certain countries, entities and individuals. Our failure to comply with export and use regulations concerning encryption technology of RSD could subject us to sanctions and penalties, including fines, and suspension or revocation of export or import privileges.

We are subject to a variety of laws and regulations in the United States, the European Union and other countries that involve, for example, user privacy, data protection and security, content and consumer protection. A number of proposals are pending before federal, state, and foreign legislative and regulatory bodies that could significantly affect our business. ExistingFor example, in 2016, a new EU data protection regime, the General Data Protection Regulation (“GDPR”) was adopted, with it fully effective on May 25, 2018, and California enacted the California Consumer Privacy Act as of January 1, 2020 (“CCPA”). The GDPR and CCPA may require us to modify our existing practices with respect to the collection, use, and disclosure of data. In particular, the GDPR provides for significant penalties in the case of non-compliance of up to €20 million or four percent of worldwide annual revenues, whichever is greater. The GDPR, CCPA and other existing and proposed laws and regulations can be costly to comply with and can delay or impede the development of new products, result in negative publicity, increase our operating costs and subject us to claims or other remedies.

In accordance with the Dodd-Frank Wall Street Reform and Consumer Protection Act, the SEC established new disclosure and reporting requirements for those companies whothat use "conflict"“conflict” minerals mined from the Democratic Republic of Congo and adjoining countries in their products, whether or not these products are manufactured by third parties. These requirements could affect the sourcing and availability of minerals that are used in the manufacture of our products. We have to date incurred costs and expect to incur significant additional costs associated with complying with the disclosure requirements, including for example, due diligence in regard to the sources of any conflict minerals used in our products, in addition to the cost of remediation and other changes to products, processes, or sources of supply as a consequence of such verification activities. Additionally, we may face reputational challenges with our customers and other stakeholders if we are unable to sufficiently verify the origins of all minerals used in our products through the due diligence procedures that we implement. We may also face challenges with government regulators and our customers and suppliers if we are unable to sufficiently verify that the metals used in our products are conflict free.

Participation in standards setting organizations may subject us to intellectual property licensing requirements or limitations that could adversely affect our business and prospects.

In the course of our participation in the development of emerging standards for some of our present and future products, we may be obligated to grant to all other participants a license to our patents that are essential to the practice of those standards on reasonable and non-discriminatory, or RAND, terms. If we fail to limit to whom we license our patents, or fail to limit the terms of any such licenses, we may be required to license our patents or other intellectual property to others in the future, which could limit the effectiveness of our patents against competitors.

Our operations are subject to risks of natural disasters, acts of war, terrorism, widespread illness or security breach at our domestic and international locations, any one of which could result in a business stoppage and negatively affect our operating results.

Our business operations depend on our ability to maintain and protect our facilities, computer systems and personnel, which are primarily located in the San Francisco Bay Area in the United States, the United Kingdom, the Netherlands India and Australia.India. The San Francisco Bay Area is in close proximity to known earthquake fault zones. Our facilities and transportation for our employees are susceptible to damage from earthquakes and other natural disasters such as fires, floods and similar events. Should a catastrophe disable our facilities, we do not have readily available alternative facilities from which we could conduct our business, so any resultant work stoppage could have a negative effect on our operating results. We also rely on our network infrastructure and technology systems for operational support and business activities which are subject to physical and cyber damage, and also susceptible to other related vulnerabilities common to networks and computer systems. Acts of terrorism, widespread illness, or global pandemics, including the current Coronavirus (COVID-19), war and any event that causes failures or interruption in our network infrastructure and technology systems could have a negative effect at our international and domestic facilities and could harm our business, financial condition, and operating results.

We do not have extensive experience in manufacturing and marketing products and, as a result, may be unable to sustain and grow a profitable commercial market for new and existing products.

We do not have extensive experience in creating, manufacturing and marketing products, including our CryptoManager platform, our RLDproducts. Our product offerings and new offerings that have resulted from our acquisition of SCS in the mobile credential and smart card solution spaces, and our acquisitions of the assets of the Snowbush IP group and the Memory Interconnect Business. These and other new offerings may present new and difficult challenges, and we may be subject to claims if customers of theseour offerings experience delays, failures, non-performance or other quality issues. In particular, we may experience difficulties with product design, qualification, manufacturing, marketing or certification that could delay or prevent our development, introduction or marketing and sales of new products. Although we intend to design our products to be fully compliant with applicable industry standards, proprietary enhancements may not in the future result in full conformance with existing industry standards under all circumstances.


If we fail to introduce products that meet the demand of our customers, or penetrate new markets in which we expend significant resources, or our marketing and sales cycles that we experience are longer than we anticipate, our revenues will be difficult to predict, may decrease over time and our financial condition could suffer. Additionally, if we concentrate resources on a new market that does not prove profitable or sustainable, it could damage our reputation and limit our growth, and our financial condition could decline.



We rely upon the accuracy of our customers’ recordkeeping, and any inaccuracies or payment disputes for amounts owed to us under our licensing agreements may harm our results of operations.

Many of our license agreements require our customers to document the manufacture and sale of products that incorporate our technology and report this data to us on a quarterly basis. While licenses with such terms give us the right to audit books and records of our customers to verify this information, audits rarely are undertaken because they can be expensive, time consuming, and potentially detrimental to our ongoing business relationship with our customers. Therefore, we typically rely on the accuracy of the reports from customers without independently verifying the information in them. Our failure to audit our customers’ books and records may result in our receiving more or less royalty revenue than we are entitled to under the terms of our license agreements. If we conduct royalty audits in the future, such audits may trigger disagreements over contract terms with our customers and such disagreements could hamper customer relations, divert the efforts and attention of our management from normal operations and impact our business operations and financial condition.

We are subject to increased inventory risks and costs because we build our products based on forecasts provided by customers before receiving purchase orders for the product.

We rely on a number of third-party providers for data center hosting facilities, equipment, maintenance and other services, and the loss of, or problems with, one or more of these providers may impede our growth or cause us to lose customers.


We rely on third-party providers to supply data center hosting facilities, equipment, maintenance and other services in order to enable us to provide some of our services, including in our offerings of our advanced mobile payment platform and smart ticketing platform, and have entered into various agreements for such services. The continuous availability of our serviceservices depends on the operations of those facilities, on a variety of network service providers and on third-party vendors. In addition, we depend on our third-party facility providers’ ability to protect these facilities against damage or interruption from natural disasters, power or telecommunications failures, criminal acts, cyber-attacks and similar events. If there are any lapses of service or damage to a facility, we could experience lengthy interruptions in our service as well as delays and additional expenses in arranging new facilities and services. Even with current and planned disaster recovery arrangements, our business could be harmed. Any interruptions or delays in our service, whether as a result of third-party error, our own error, natural disasters, criminal acts, security breaches or other causes, whether accidental or willful, could harm our relationships with customers, harm our reputation and cause our revenue to decrease and/or our expenses to increase. Also, in the event of damage or interruption, our insurance policies may not adequately compensate us for any losses that we may incur. These factors in turn could further reduce our revenue, subject us to liability and cause us to issue credits or cause us to lose customers, any of which could materially adversely affect our business.


We rely on third parties for a variety of services, including manufacturing, and these third parties’ failure to perform these services adequately could materially and adversely affect our business.


We rely on third parties for a variety of services, including our manufacturing supply chain partners and third parties within our sales and distribution channels. Certain of these third parties are, and may be, our sole manufacturer or sole source of certain production materials. If we fail to manage our relationshiprelationships with these manufacturers and suppliers effectively, or if they experience delays, disruptions, capacity constraints or quality control problems in their operations, our ability to ship products to our customers could be impaired and our competitive position and reputation could be harmed. In addition, any adverse change in any of our manufacturers and suppliers’ financial or business condition could disrupt our ability to supply quality products to our customers. If we are required to change our manufacturers, we may lose revenue, incur increased costs and damage our end-customer relationships. In addition, qualifying a new manufacturer and commencing production can be an expensive and lengthy process. If our third partythird-party manufacturers or suppliers are unable to provide us with adequate supplies of high-quality products for any other reason, we could experience a delay in our order fulfillment, and our business, operating results and financial condition would be adversely affected. In the event these and other third parties we rely on fail to provide their services adequately, including as a result of errors in their systems or events beyond their control, or refuse to provide these services on terms acceptable to us or at all, and we are not able to find suitable alternatives, our business may be materially and adversely affected. In addition, our orders may represent a relatively small percentage of the overall orders received by our manufacturers from their customers. As a result, fulfilling our orders may not be considered a priority in the event our manufacturers are constrained in their ability to fulfill all of their customer obligations in a timely manner. If our manufacturers are unable to provide us with adequate supplies of high-quality products, or if we or our manufacturers are unable to obtain adequate quantities of components, it could cause a delay in our order fulfillment, in which case our business, operating results and financial condition could be adversely affected.


Warranty, service level agreement and product liability claims brought against us could cause us to incur significant costs and adversely affect our operating results as well as our reputation and relationships with customers.


We may from time to time be subject to warranty, service level agreement and product liability claims with regard to product performance and our services. We could incur material losses as a result of warranty, support, repair or replacement costs in response to customer complaints or in connection with the resolution of contemplated or actual legal proceedings relating to such claims. In addition to potential losses arising from claims and related legal proceedings, warranty and product liability claims could affect our reputation and our relationship with customers. We generally attempt to limit the maximum amount of indemnification or liability that we could be exposed to under our contracts, however, this is not always possible.


Any failure in our delivery of high-quality technical support services may adversely affect our relationships with our customers and our financial results.


Our customers depend on our support organization to resolve technical issues and provide ongoing maintenance relating to our products and services. We may be unable to respond quickly enough to accommodate short-term increases in customer demand for support services. Increased customer demand for these services, without corresponding revenues, could increase costs and adversely affect our operating results. In addition, our sales process is highly dependent on our offerings and business

reputation and on positive recommendations from our existing customers. Any failure to maintain high-quality technical support, or a market perception that we do not maintain high-quality support, could adversely affect our reputation, our ability to sell our solutions to existing and prospective customers, and our business, operating results and financial position.


Certain software that we use in certain of our products is licensed from third parties and, for that reason, may not be available to us in the future, which has the potential to delay product development and production or cause us to incur additional expense, which could materially adversely affect our business, financial condition, operating results and cash flow.


Some of our products and services contain software licensed from third parties. Some of these licenses may not be available to us in the future on terms that are acceptable to us or allow our products to remain competitive. The loss of these licenses or the inability to maintain any of them on commercially acceptable terms could delay development of future offerings or the enhancement of existing products and services. We may also choose to pay a premium price for such a license in certain circumstances where continuity of the licensed product would outweigh the premium cost of the license. The unavailability of these licenses or the necessity of agreeing to commercially unreasonable terms for such licenses could materially adversely affect our business, financial condition, operating results and cash flow.


Certain software we use is from open source code sources, which, under certain circumstances, may lead to unintended consequences and, therefore, could materially adversely affect our business, financial condition, operating results and cash flow.


We use open source software in our services, including our advanced mobile payment platform and smart ticketing platform, and we intend to continue to use open source software in the future. From time to time, there have been claims challenging the ownership of open source software against companies that incorporate open source software into their products or alleging that these companies have violated the terms of an open source license. As a result, we could be subject to lawsuits by parties claiming ownership of what we believe to be open source software or alleging that we have violated the terms of an open source license. Litigation could be costly for us to defend, have a negative effect on our operating results and financial condition or require us to devote additional research and development resources to change our solutions. In addition, if we were to combine our proprietary software solutions with open source software in certain manners, we could, under certain open source licenses, be required to publicly release the source code of our proprietary software solutions. If we inappropriately use open source software, we may be required to re-engineer our solutions, discontinue the sale of our solutions, release the source code of our proprietary software to the public at no cost or take other remedial actions. There is a risk that open source licenses could be construed in a way that could impose unanticipated conditions or restrictions on our ability to commercialize our solutions, which could adversely affect our business, operating results and financial condition.


Our business and operating results could be harmed if we undertake any restructuring activities.


From time to time, we may undertake restructurings of our business, such as the restructuringincluding discontinuing certain products, services and plan of termination that we undertooktechnologies and planned reductions in the fourth quarter of 2015.force. There are several factors that could cause restructurings to have adverse effects on our business, financial condition and results of operations. These include potential disruption of our operations, the development of our technology, the deliveries to our customers and other aspects of our business. Loss of sales, service and engineering talent, in particular, could damage our business. Any restructuring would require substantial management time and attention and may divert management from other important work. Employee reductions or other restructuring activities also would cause us to incur restructuring and related expenses such as severance expenses. Moreover, we could encounter delays in executing any restructuring plans, which could cause further disruption and additional unanticipated expense.

Problems with our information systems could interfere with our business and could adversely impact our operations.

We rely on our information systems and those of third parties for fulfilling licensing and contractual obligations, processing customer orders, delivering products, providing services and support to our customers, billing and tracking our customer orders, performing accounting operations and otherwise running our business. If our systems fail, our disaster and data recovery planning and capacity may prove insufficient to enable timely recovery of important functions and business records. Any disruption in our information systems and those of the third parties upon whom we rely could have a significant impact on our business. Additionally, our information systems may not support new business models and initiatives and significant investments could be required in order to upgrade them. Delays in adapting our information systems to address new business models and accounting standards could limit the success or result in the failure of such initiatives and impair the effectiveness of our internal controls. Even if we do not encounter these adverse effects, the implementation of these enhancements may be much more costly than we anticipated. If we are unable to successfully implement the information systems enhancements as planned, our operating results could be negatively impacted.

Risks Related to Capitalization Matters and Corporate Governance
The price of our common stock may continue to fluctuate.

Our common stock is listed on The NASDAQ Global Select Market under the symbol “RMBS.” The trading price of our common stock has at times experienced price volatility and may continue to fluctuate significantly in response to various factors, some of which are beyond our control.  Some of these factors include:

any progress, or lack of progress, real or perceived, in the development of products that incorporate our innovations and technology companies'companies’ acceptance of our products, including the results of our efforts to expand into new target markets;
our signing or not signing new licenses or renewing existing licenses, and the loss of strategic relationships with any customer;
announcements of technological innovations or new products by us, our customers or our competitors;
changes in our strategies, including changes in our licensing focus and/or acquisitions or dispositions of companies or businesses with business models or target markets different from our own;

core;
positive or negative reports by securities analysts as to our expected financial results and business developments;
developments with respect to patents or proprietary rights and other events or factors;
new litigation and the unpredictability of litigation results or settlements; and
repurchases of our common stock on the open market;
issuance of additional securities by us, including in acquisitions.acquisitions, or large cash payments, including in acquisitions; and
changes in accounting pronouncements, including the effects of ASC 606 and ASC 842.

In addition, the stock market in general, and prices for companies in our industry in particular, have experienced extreme volatility that often has been unrelated to the operating performance of such companies. These broad market and industry fluctuations may adversely affect the price of our common stock, regardless of our operating performance.

We have outstanding senior convertible notes in an aggregate principal amount totaling $138.0$172.5 million. Because these notes are convertible into shares of our common stock, volatility or depressed prices of our common stock could have a similar effect on the trading price of such notes. In addition, the existence of these notes may encourage short selling in our common stock by market participants because the conversion of the notes could depress the price of our common stock.

We have been party to, and may in the future be subject to, lawsuits relating to securities law matters which may result in unfavorable outcomes and significant judgments, settlements and legal expenses which could cause our business, financial condition and results of operations to suffer.

We and certain of our current and former officers and directors, as well as our current auditors, were subject from 2006 to 2011 to several stockholder derivative actions, securities fraud class actions and/or individual lawsuits filed in federal court against us and certain of our current and former officers and directors. The complaints generally alleged that the defendants violated the federal and state securities laws and stated state law claims for fraud and breach of fiduciary duty. Although to date these complaints have either been settled or dismissed, the amount of time to resolve any future lawsuits is uncertain, and these matters could require significant management and financial resources. Unfavorable outcomes and significant judgments, settlements and legal expenses in litigation related to any future securities law claims could have material adverse impacts on our business, financial condition, results of operations, cash flows and the trading price of our common stock.

We are leveraged financially, which could adversely affect our ability to adjust our business to respond to competitive pressures and to obtain sufficient funds to satisfy our future research and development needs, to protect and enforce our intellectual property, and to meet other needs.

We have material indebtedness. In August 2013,November 2017, we issued $138.0$172.5 million aggregate principal amount of our 20182023 Notes, the entire amount of which remainremains outstanding. The degree to which we are leveraged could have negative consequences, including, but not limited to, the following:

we may be more vulnerable to economic downturns, less able to withstand competitive pressures and less flexible in responding to changing business and economic conditions;
our ability to obtain additional financing in the future for working capital, capital expenditures, acquisitions, litigation, general corporate or other purposes may be limited;
a substantial portion of our cash flows from operations in the future may be required for the payment of theinterest and principal amount of our existing indebtedness when it becomes due at maturity in August 2018;February 2023; and

we may be required to make cash payments upon any conversion of the 20182023 Notes, which would reduce our cash on hand.

A failure to comply with the covenants and other provisions of our debt instruments could result in events of default under such instruments, which could permit acceleration of all of our outstanding 20182023 Notes. Any required repurchase of the 20182023 Notes as a result of a fundamental change or acceleration of the 20182023 Notes would reduce our cash on hand such that we would not have those funds available for use in our business.
If we are at any time unable to generate sufficient cash flows from operations to service our indebtedness when payment is due, we may be required to attempt to renegotiate the terms of the instruments relating to the indebtedness, seek to refinance all or a portion of the indebtedness or obtain additional financing. There can be no assurance that we will be able to successfully renegotiate such terms, that any such refinancing would be possible or that any additional financing could be obtained on terms that are favorable or acceptable to us.

Compliance with changing regulation of corporate governance and public disclosure may result in additional expenses.

Changing laws, regulations and standards relating to corporate governance and public disclosure have historically created uncertainty for companies such as ours. Any new or changed laws, regulations and standards are subject to varying interpretations due to their lack of specificity, and as a result, their application in practice may evolve over time as new guidance is provided by regulatory and governing bodies. This could result in continuing uncertainty regarding compliance matters and higher costs necessitated by ongoing revisions to disclosure and governance practices.


Our certificate of incorporation and bylaws, Delaware law, our outstanding convertible notes and certain other agreements contain provisions that could discourage transactions resulting in a change in control, which may negatively affect the market price of our common stock.

Our certificate of incorporation, our bylaws and Delaware law contain provisions that might enable our management to discourage, delay or prevent a change in control. In addition, these provisions could limit the price that investors would be willing to pay in the future for shares of our common stock. Pursuant to such provisions:
our board of directors is authorized, without prior stockholder approval, to create and issue preferred stock, commonly referred to as “blank check” preferred stock, with rights senior to those of common stock, which means that a stockholder rights plan could be implemented by our board;
our board of directors is staggered into two classes, only one of which is elected at each annual meeting;
stockholder action by written consent is prohibited;
nominations for election to our board of directors and the submission of matters to be acted upon by stockholders at a meeting are subject to advance notice requirements;
certain provisions in our bylaws and certificate of incorporation such as notice to stockholders, the ability to call a stockholder meeting, advance notice requirements and action of stockholders by written consent may only be amended with the approval of stockholders holding 66 2/3% of our outstanding voting stock;
our stockholders have no authority to call special meetings of stockholders; and
our board of directors is expressly authorized to make, alter or repeal our bylaws.

We are also subject to Section 203 of the Delaware General Corporation Law, which provides, subject to enumerated exceptions, that if a person acquires 15% or more of our outstanding voting stock, the person is an “interested stockholder” and may not engage in any “business combination” with us for a period of three years from the time the person acquired 15% or more of our outstanding voting stock.
Certain provisions of our outstanding 2018 Notes could make it more difficult or more expensive for a third party to acquire us. Upon the occurrence of certain transactions constituting a fundamental change, holders of such 2018 Notes will have the right, at their option, to require us to repurchase, at a cash repurchase price equal to 100% of the principal amount plus accrued and unpaid interest on such 2018 Notes, all or a portion of their 2018 Notes. We may also be required to increase the conversion rate of such 2018 Notes in the event of certain fundamental changes.

Unanticipated changes in our tax rates or in the tax laws and regulations could expose us to additional income tax liabilities which could affect our operating results and financial condition.

We are subject to income taxes in both the United States and various foreign jurisdictions. Significant judgment is required in determining our worldwide provision for income taxes and, in the ordinary course of business, there are many transactions and calculations where the ultimate tax determination is uncertain. Our effective tax rate could be adversely affected by changes

in the mix of earnings in countries with differing statutory tax rates, changes in the valuation of deferred tax assets and liabilities, changes in tax laws and regulations as well as other factors. Our tax determinations are regularly subject to audit by tax authorities and developments in those audits could adversely affect our income tax provision, and we are currently undergoing such audits of certain of our tax returns. Although we believe that our tax estimates are reasonable, the final determination of tax audits or tax disputes may be different from what is reflected in our historical income tax provisions which could affect our operating results.
Litigation, Regulation and Business Risks Related to our Intellectual Property
Adverse litigation results could affect our business.

We may be subject to legal claims or regulatory matters involving consumer, stockholder, employment, competition, intellectual property and other issues on a global basis. Litigation can be lengthy, expensive and disruptive to our operations, and results cannot be predicted with certainty. An adverse decision could include monetary damages or, in cases for which injunctive relief is sought, an injunction prohibiting us from manufacturing or selling one or more of our products or technologies. If we were to receive an unfavorable ruling on a matter, our business, operating results or financial condition could be materially harmed.

We have in the past, and may in the future, become engaged in litigation stemming from our efforts to protect and enforce our patents and intellectual property and make other claims, which could adversely affect our intellectual property rights, distract our management and cause substantial expenses and declines in our revenue and stock price.

We seek to diligently protect our intellectual property rights and will continue to do so. While we are not currently involved in intellectual property litigation, any future litigation, whether or not determined in our favor or settled by us, would be expected to be costly, may cause delays applicable to our business (including delays in negotiating licenses with other actual or potential customers), would be expected to tend to discourage future design partners, would tend to impair adoption of our existing technologies and would divert the efforts and attention of our management and technical personnel from other business operations. In addition, we may be unsuccessful in any litigation if we have difficulty obtaining the cooperation of former employees and agents who were involved in our business during the relevant periods related to our litigation and are now needed to assist in cases or testify on our behalf. Furthermore, any adverse determination or other resolution in litigation could result in our losing certain rights beyond the rights at issue in a particular case, including, among other things: our being effectively barred from suing others for violating certain or all of our intellectual property rights; our patents being held invalid

or unenforceable or not infringed; our being subjected to significant liabilities; our being required to seek licenses from third parties; our being prevented from licensing our patented technology; or our being required to renegotiate with current customers on a temporary or permanent basis.

From time to time, we are subject to proceedings by government agencies that may result in adverse determinations against us and could cause our revenue to decline substantially.

An adverse resolution by or with a governmental agency could result in severe limitations on our ability to protect and license our intellectual property, and could cause our revenue to decline substantially. Third parties have and may attempt to use adverse findings by a government agency to limit our ability to enforce or license our patents in private litigations, to challenge or otherwise act against us with respect to such government agency proceedings.


Further, third parties have sought and may seek review and reconsideration of the patentability of inventions claimed in certain of our patents by the U.S. Patent and Trademark Office (“USPTO”) and/or the European Patent Office (the “EPO”). Any re-examination or inter parties review proceedings may be reviewedinitiated by the USPTO'sUSPTO’s Patent Trial and Appeal Board (“PTAB”). The PTAB and the related former Board of Patent Appeals and Interferences have previously issued decisions in a few cases, finding some challenged claims of Rambus'Rambus’ patents to be valid, and others to be invalid. Decisions of the PTAB are subject to further USPTO proceedings and/or appeal to the Court of Appeals for the Federal Circuit. A final adverse decision, not subject to further review and/or appeal, could invalidate some or all of the challenged patent claims and could also result in additional adverse consequences affecting other related U.S. or European patents, including in any intellectual property litigation. If a sufficient number of such patents are impaired, our ability to enforce or license our intellectual property would be significantly weakened and could cause our revenue to decline substantially.


The pendency of any governmental agency acting as described above may impair our ability to enforce or license our patents or collect royalties from existing or potential customers, as any litigation opponents may attempt to use such proceedings to delay or otherwise impair any pending cases and our existing or potential customers may await the final outcome of any proceedings before agreeing to new licenses or to paying royalties.

Litigation or other third-party claims of intellectual property infringement could require us to expend substantial resources and could prevent us from developing or licensing our technology on a cost-effective basis.

Our research and development programs are in highly competitive fields in which numerous third parties have issued patents and patent applications with claims closely related to the subject matter of our programs. We have also been named in the past, and may in the future be named, as a defendant in lawsuits claiming that our technology infringes upon the intellectual property rights of third parties. As we develop additional products and technology, we may face claims of infringement of various patents and other intellectual property rights by third parties. In the event of a third-party claim or a successful infringement action against us, we may be required to pay substantial damages, to stop developing and licensing our infringing technology, to develop non-infringing technology, and to obtain licenses, which could result in our paying substantial royalties or our granting of cross licenses to our technologies. We may not be able to obtain licenses from other parties at a reasonable cost, or at all, which could cause us to expend substantial resources, or result in delays in, or the cancellation of, new products. Moreover, customers and/or suppliers of our products may seek indemnification for alleged infringement of intellectual property rights.  We could be liable for direct and consequential damages and expenses including attorneys’ fees. A future obligation to indemnify our customers and/or suppliers may harm our business, financial condition and operating results.

If we are unable to protect our inventions successfully through the issuance and enforcement of patents, our operating results could be adversely affected.

We have an active program to protect our proprietary inventions through the filing of patents. There can be no assurance, however, that:

any current or future U.S. or foreign patent applications will be approved and not be challenged by third parties;
our issued patents will protect our intellectual property and not be challenged by third parties;
the validity of our patents will be upheld;
our patents will not be declared unenforceable;
the patents of others will not have an adverse effect on our ability to do business;
Congress or the U.S. courts or foreign countries will not change the nature or scope of rights afforded patents or patent owners or alter in an adverse way the process for seeking or enforcing patents;
changes in law will not be implemented, or changes in interpretation of such laws will occur, that will affect our ability to protect and enforce our patents and other intellectual property;
new legal theories and strategies utilized by our competitors will not be successful;

others will not independently develop similar or competing chip interfaces or design around any patents that may be issued to us; or
factors such as difficulty in obtaining cooperation from inventors, pre-existing challenges or litigation, or license or other contract issues will not present additional challenges in securing protection with respect to patents and other intellectual property that we acquire.

If any of the above were to occur, our operating results could be adversely affected.

Furthermore, recent patent reform legislation, such as the Leahy-Smith America Invents Act, could increase the uncertainties and costs surrounding the prosecution of any patent applications and the enforcement or defense of our licensed patents. The federal courts, the USPTO, the Federal Trade Commission, and the U.S. International Trade Commission have also recently taken certain actions and issued rulings that have been viewed as unfavorable to patentees. While we cannot predict what form any new patent reform laws or regulations may ultimately take, or what impact recent or future reforms may have on our business, any laws or regulations that restrict or negatively impact our ability to enforce our patent rights against third parties could have a material adverse effect on our business.

In addition, our patents will continue to expire according to their terms, with expected expiration dates ranging from 20172020 to 2038. Our failure to continuously develop or acquire successful innovations and obtain patents on those innovations could significantly harm our business, financial condition, results of operations, or cash flows.

Our inability to protect and own the intellectual property we create would cause our business to suffer.

We rely primarily on a combination of license, development and nondisclosure agreements, trademark, trade secret and copyright law and contractual provisions to protect our non-patentable intellectual property rights. If we fail to protect these intellectual property rights, our customers and others may seek to use our technology without the payment of license fees and

royalties, which could weaken our competitive position, reduce our operating results and increase the likelihood of costly litigation. The growth of our business depends in part on the use of our intellectual property in the products of third partythird-party manufacturers, and our ability to enforce intellectual property rights against them to obtain appropriate compensation. In addition, effective trade secret protection may be unavailable or limited in certain foreign countries. Although we intend to protect our rights vigorously, if we fail to do so, our business will suffer.


Effective protection of trademarks, copyrights, domain names, patent rights, and other intellectual property rights is expensive and difficult to maintain, both in terms of application and maintenance costs, as well as the costs of defending and enforcing those rights. The efforts we have taken to protect our intellectual property rights may not be sufficient or effective. Our intellectual property rights may be infringed, misappropriated, or challenged, which could result in them being narrowed in scope or declared invalid or unenforceable. In addition, the laws or practices of certain countries do not protect our proprietary rights to the same extent as do the laws of the United States. Significant impairments of our intellectual property rights, and limitations on our ability to assert our intellectual property rights against others, could have a material and adverse effect on our business.


Third parties may claim that our products or services infringe on their intellectual property rights, exposing us to litigation that, regardless of merit, may be costly to defend.


Our success and ability to compete are also dependent upon our ability to operate without infringing upon the patent, trademark and other intellectual property rights of others. Third parties may claim that our current or future products or services infringe upon their intellectual property rights. Any such claim, with or without merit, could be time consuming, divert management’s attention from our business operations and result in significant expenses. We cannot assure you that we would be successful in defending against any such claims. In addition, parties making these claims may be able to obtain injunctive or other equitable relief affecting our ability to license the products that incorporate the challenged intellectual property. As a result of such claims, we may be required to obtain licenses from third parties, develop alternative technology or redesign our products. We cannot be sure that such licenses would be available on terms acceptable to us, if at all. If a successful claim is made against us and we are unable to develop or license alternative technology, our business, financial condition, operating results and cash flows could be materially adversely affected.

We rely upon the accuracy of our customers' recordkeeping, and any inaccuracies or payment disputes for amounts owed to us under our licensing agreements may harm our results of operations.

Many of our license agreements require our customers to document the manufacture and sale of products that incorporate our technology and report this data to us on a quarterly basis. While licenses with such terms give us the right to audit books and records of our customers to verify this information, audits rarely are undertaken because they can be expensive, time

consuming, and potentially detrimental to our ongoing business relationship with our customers. Therefore, we typically rely on the accuracy of the reports from customers without independently verifying the information in them. Our failure to audit our customers' books and records may result in our receiving more or less royalty revenue than we are entitled to under the terms of our license agreements. If we conduct royalty audits in the future, such audits may trigger disagreements over contract terms with our customers and such disagreements could hamper customer relations, divert the efforts and attention of our management from normal operations and impact our business operations and financial condition.
Any dispute regarding our intellectual property may require us to indemnify certain customers, the cost of which could severely hamper our business operations and financial condition.

In any potential dispute involving our patents or other intellectual property, our customers could also become the target of litigation. While we generally do not indemnify our customers, some of our agreements provide for indemnification, and some require us to provide technical support and information to a customer that is involved in litigation involving use of our technology. In addition, we may be exposed to indemnification obligations, risks and liabilities that were unknown at the time of acquisitions, including with respect tothat we acquired assets or businesses for our acquisitions of SCS, the assets of the Snowbush IP group and the Memory Interconnect Business, and we may agree to indemnify others in the future.operations. Any of these indemnification and support obligations could result in substantial and material expenses. In addition to the time and expense required for us to indemnify or supply such support to our customers, a customer'scustomer’s development, marketing and sales of licensed semiconductors, lighting, mobile communications and data security technologies could be severely disrupted or shut down as a result of litigation, which in turn could severely hamper our business operations and financial condition as a result of lower or no royalty payments.

Item 1B.Unresolved Staff Comments
None.

23



Item 2.Properties
As of December 31, 2016,2019, we occupied offices in the leased facilities described below:
Number of
Offices
Under Lease
 Location Primary Use
67 United States  
  Sunnyvale, CA (Corporate Headquarters) Executive and administrative offices, research and development, sales and marketing and service functions
  San Jose, CA (Future Corporate Headquarters - expected move in date is mid-2020)Executive and administrative offices, research and development, sales and marketing and service functions
Chapel Hill, NC Research and development
Brecksville, OH (2)Research and development, prototyping and light manufacturing facility
  San Francisco, CA Research and development
  Richardson, TXBeaverton, OR Research and development
  Westlake Village,Agoura Hills, CAResearch and development
Westminster, CA Research and development
1 Bangalore, India Administrative offices, research and development and service functions
1 Tokyo, Japan Business development
1 Yokohama, JapanBusiness development
1Seoul, Korea Business development
1 Shanghai, China Business development
12 Taipei, TaiwanBusiness development
1Melbourne, Australia Business development
1 Rotterdam, The Netherlands Administrative offices, researchResearch and development sales and marketing and service functions
1 East Kilbride,Vught, The NetherlandsResearch and development
1Glasgow, United Kingdom Administrative offices, researchResearch and development sales and marketing and service functions
1 Toronto, Canada Research and development
1 Espoo, Finland Research and development


Item 3.Legal Proceedings
We are not currently a party to any material pending legal proceeding; however, from time to time, we may become involved in legal proceedings or be subject to claims arising in the ordinary course of our business. Although the results of litigation and claims cannot be predicted with certainty, we currently believe that the final outcome of these ordinary course matters will not have a material adverse effect on our business, operating results, financial position or cash flows. Regardless of the outcome, litigation can have an adverse impact on us because of defense and settlement costs, diversion of management attention and resources and other factors.
Item 4.Mine Safety Disclosures
Not applicable.
PART II

Item 5.Market for Registrant’s Common Equity, Related Stockholder Matters and Issuer Purchases of Equity Securities
Our Common Stock is listed on The NASDAQ Global Select Market under the symbol “RMBS.” The following table sets forth for the periods indicated the high and low sales price per share of our common stock as reported on The NASDAQ Global Select Market.
Year Ended Year EndedYear Ended Year Ended
December 31, 2016 December 31, 2015December 31, 2019 December 31, 2018
High Low High LowHigh Low High Low
First Quarter$13.99
 $10.66
 $12.88
 $10.01
$10.93
 $7.55
 $14.63
 $11.85
Second Quarter$13.97
 $11.13
 $15.49
 $12.44
$12.24
 $10.50
 $14.30
 $12.54
Third Quarter$14.50
 $11.42
 $14.80
 $10.36
$14.29
 $11.23
 $13.61
 $10.76
Fourth Quarter$14.39
 $11.44
 $14.07
 $9.86
$14.83
 $12.45
 $10.99
 $7.17

The graph below compares the cumulative 5-year total return of holders of Rambus Inc.'s’s common stock with the cumulative total returns of the NASDAQ Composite index and the RDG Semiconductor Composite index. The graph tracks the performance of a $100 investment in our common stock and in each index (with the reinvestment of all dividends) from December 31, 20112014 to December 31, 2016.2019.


chart-33d1ec5d554bc56ba88.jpg
Fiscal years ending:
12/1112/1212/1312/1412/1512/16
Base Period
12/31/14
12/31/1512/31/1612/31/1712/31/1812/31/19
Rambus Inc.100.0064.50125.43146.89153.51182.38$100.00$104.51$124.17$128.22$69.16$124.21
NASDAQ Composite100.00116.41165.47188.69200.32216.54$100.00$106.96$116.45$150.96$146.67$200.49
RDG Semiconductor Composite100.00101.55137.33170.90153.05206.30$100.00$91.76$122.76$169.41$153.35$234.06
The stock price performance included in this graph is not necessarily indicative offuture stock price performance.
Information regarding our securities authorized for issuance under equity compensation plans will be included in Item 12, “Security Ownership of Certain Beneficial Owners and Management and Related Stockholder Matters,” of this report on Form 10-K.

As of January 31, 2017,2020, there were 521454 holders of record of our common stock. Since many of the shares of our common stock are held by brokers and other institutions on behalf of stockholders, we are unable to estimate the total number of beneficial stockholders represented by these record holders.
We have never paid or declared any cash dividends on our common stock or other securities.

Share Repurchase Program
During the year ended December 31, 2019, we did not repurchase any shares of our common stock under our share repurchase program.
On January 21, 2015, our Board approved a share repurchase program authorizing the repurchase of up to an aggregate of 20.0 million shares. Share repurchases under the plan may be made through the open market, established plans or privately negotiated transactions in accordance with all applicable securities laws, rules, and regulations. There is no expiration date applicable to the plan. As part of the broader share repurchase program previously authorized by our Board on January 21, 2015, we initiated an accelerated share repurchase program with Citibank, N.A. on March 5, 2018 which was completed in the second quarter of 2018. After giving effect to thesuch accelerated share repurchase program, detailed in the table below, we had remaining authorization to repurchase approximately 11.53.6 million shares.
We record stock repurchases as a reduction to stockholders’ equity. We record a portion of the purchase price of the repurchased shares as an increase to accumulated deficit when the price of the shares repurchased exceeds the average original proceeds per share received from the issuance of common stock.
Period Total Number of Shares Purchased Average Price Paid per Share Total Number of Shares Purchased as Part of Publicly Announced Plans or Programs Maximum Number of Shares that May Yet be Purchased Under the Plans or Programs
         
Cumulative shares repurchased as of December 31, 2015 (1) 7,812,500
 $11.70 7,812,500
 12,187,500
April 1, 2016 - April 30, 2016 (1) 735,861
 $11.70 735,861
 11,451,639
Cumulative shares repurchased as of December 31, 2016 8,548,361
   8,548,361
  
(1) In the fourth quarter of 2015, we entered into an accelerated share repurchase program with a financial institution to repurchase an aggregate of $100.0 million of our common stock. We made an upfront payment of $100.0 million pursuant to the accelerated share repurchase program and received an initial delivery of 7.8 million shares which were retired. During the second quarter of 2016, the accelerated share repurchase program was completed and we received an additional 0.7 million shares of our common stock, which were retired, as the final settlement of the accelerated share repurchase program. The total shares of our common stock received and retired under the terms of the accelerated share repurchase program were 8.5 million, with an average price paid per share of $11.70. See Note 13, “Stockholders' Equity,” of Notes to Consolidated Financial Statements of this Form 10-K for further discussion.
Item 6.Selected Financial Data
The following selected consolidated financial data as of and for the years ended December 31, 2019, 2018, 2017, 2016 2015, 2014, 2013 and 20122015 was derived from our consolidated financial statements. The following selected consolidated financial data should be read in conjunction with Item 7, “Management’s Discussion and Analysis of Financial Condition and Results of Operations,” and Item 8, “Financial Statements and Supplementary Data,” and other financial data included elsewhere in this report. Our historical results of operations are not necessarily indicative of results of operations to be expected for any future period.


Years Ended December 31,
Years Ended December 31,2019 (6) 2018 (3) (4) (5) 2017 (3) (4) 2016 (1) (2) 2015 (2) (3) (4)
2016 (1) (2) 2015 (2) (3) (4) 2014 (2) 2013 (1) (2) 2012 (1)         
(In thousands, except per share amounts)(In thousands, except per share amounts)
Total revenue$336,597
 $296,278
 $296,558
 $271,501
 $234,051
$224,027
 $231,201
 $393,096
 $336,597
 $296,278
Net income (loss)$6,820
 $211,388
 $26,201
 $(33,748) $(134,336)$(90,419) $(157,957) $(22,862) $6,820
 $211,388
Net income (loss) per share:                  
Basic$0.06
 $1.84
 $0.23
 $(0.30) $(1.21)$(0.81) $(1.46) $(0.21) $0.06
 $1.84
Diluted$0.06
 $1.80
 $0.22
 $(0.30) $(1.21)$(0.81) $(1.46) $(0.21) $0.06
 $1.80
Consolidated Balance Sheet Data:                  
Cash, cash equivalents and marketable securities$172,182
 $287,706
 $300,109
 $387,662
 $203,330
$407,664
 $277,764
 $329,376
 $172,182
 $287,706
Total assets$783,496
 $718,021
 $586,235
 $710,485
 $586,886
$1,338,986
 $1,361,155
 $891,072
 $783,496
 $718,021
Convertible notes$126,167
 $119,418
 $113,045
 $270,782
 $146,630
$148,788
 $141,934
 $213,898
 $126,167
 $119,418
Stockholders’ equity$552,782
 $526,533
 $391,622
 $340,229
 $321,594
$970,918
 $1,012,112
 $571,584
 $552,782
 $526,533

(1)The net income for the year ended December 31, 2016 included $18.3 million of impairment of in-process research and development intangible asset and a reduction of operating expenses due to the change in our contingent consideration liability of $6.8 million. The net loss for the years ended December 31, 2013 and 2012 included $17.8 million and $35.5 million, respectively, of impairment of goodwill and long-lived assets.
(2)The net income (loss) for the years ended December 31, 2016 2015, 2014 and 20132015 included $0.6 million $2.0 million, $2.0 million, and $0.5$2.0 million, respectively, of gain from settlement which was reflected as a reduction of operating costs and expenses.
(3)The net loss for the year ended December 31, 2018 included a $113.7 million impact of an increase in our deferred tax asset valuation allowance. The net loss for the year ended December 31, 2017 included a $21.5 million impact due to the recording of a deferred tax asset valuation allowance and $20.7 million related to re-measurement of deferred tax assets as a result of the tax law changes. The net income for the year ended December 31, 2015 included $174.5 million related to the reversal of the deferred tax asset valuation allowance.
(4)Stockholders'Stockholders’ equity includes $50.0 million paid under the accelerated share repurchase program initiated in both March 2018 and May 2017, and $100.0 million paid under the accelerated share repurchase program initiated in October 2015 as well as the $174.5 million net impact of the reversal of the deferred tax asset valuation allowance.
(5)Reflects the impact from the adoption of ASC 606 in 2018. Refer to Note 2, “Summary of Significant Accounting Policies,” of Notes to Consolidated Financial Statements of this Form 10-K for further discussion.



(6)The net loss for the year ended December 31, 2019 included $7.4 million of impairment of assets held for sale related to the Company’s Payments and Ticketing businesses, which was included in operating costs and expenses. Refer to Note 17, “Divestiture,” of Notes to Consolidated Financial Statements of this Form 10-K for further discussion.
Item 7.Management’s Discussion and Analysis of Financial Condition and Results of Operations
This report contains forward-looking statements within the meaning of Section 27Aof the Securities Act of 1933 and Section 21E of the Securities Exchange Act of1934 as described in more detail under “Note Regarding Forward-Looking Statements.” Our forward-lookingstatements are based on current expectations, forecasts and assumptions and aresubject to risks, uncertainties and changes in condition, significance, value andeffect. As a result of the factors described herein, and in the documentsincorporated herein by reference, including, in particular, those factors describedunder “Risk Factors,” we undertake no obligation to publicly disclose any revisionsto these forward-looking statements to reflect events or circumstances occurringsubsequent to filing this report with the Securities and Exchange Commission.

The following discussion and analysis should be read in conjunction with the consolidated financial statements and related notes that are included elsewhere in this report.

Executive Summary
In 2016, we continuedHighlights from our transition from a pure IP licensing model to one that delivers increasing value to the market through chips, customizable IP cores, software and services. In line with our growth strategy, we acquired four businesses in 2016 in the fields of mobile payments, smart ticketing, memory buffer chips and SerDes IP cores. We also continued to execute on our traditional patent licensing business by signing key license agreements with AMD, Xilinx and others. Key 2016 financialannual results included:

were as follows:
Revenue of $336.6$224.0 million;
Total Operating Costscosts and Expensesexpenses of $303.0 million$328.6 million;
Annual GAAP diluted net incomeloss per share of $0.06; and$0.81;

OperatingNet cash flowsprovided by operating activities of $92.5$128.5 million

We redefined our perimeter in 2019 with significant merger and acquisition activity throughout the year and focused the Company on Memory Interface Chips and Silicon IP solutions for the semiconductor market. We closed the sale of our Payments and Ticketing businesses to Visa and completed two silicon IP acquisitions, Northwest Logic for digital controllers, and the Secure Silicon IP and Protocols businesses of Verimatrix, formerly Inside Secure. Further, we delivered the second consecutive year of record revenue from products, with combined results from our Memory Interface Chips and Silicon IP businesses.
Business Overview
Rambus creates innovative hardwareis a premier Silicon IP and software technologies, driving advancements fromChip provider, delivering high-speed interface and embedded security solutions to make data faster and safer. With 30 years of innovation, we continue to develop and license the data centerfoundational technology essential to the mobile edge. Ourall modern system on chips customizable(SoCs) and computing systems. The Company delivers a broad range of semiconductor solutions including architecture licenses, high-speed physical and digital controller Interface IP cores, patent licenses, software, services,Security IP cores and other innovations improveprotocols, and memory interface Chips.

Our strategic objectives are to focus our product portfolio and research around our core strength in semiconductor technologies, optimize the competitive advantageCompany for operational efficiency, and leverage our strong cash generation to re-invest for growth. We continue to maximize synergies across our businesses and customer base, leveraging the significant overlap in our ecosystem of customers, partners and influencers. By delivering comprehensive solutions for secure, connected semiconductors, we are able to bring better value to our customers and improved profitability for the Company.

In 2019, we redefined our perimeter through the successful divestiture of our customers. We collaborate withPayments and Ticketing businesses, which allowed us to focus the industry, partnering withCompany on providing leading ASICsolutions for the semiconductor market. The Rambus product and SoC designers, foundries, IP developers, processor companies, EDA companies and validation labs. Our innovations are integrated into a wide range of devices and systems, powering and securing diverse applications, including Big Data, Internet of Things, mobile, consumer and media platforms.

While we have historically focused our efforts on the development of technologies for memory, SerDes and other chip interfaces, we have expanded our portfolio of inventions and solutions to address chip and system security, mobile payments and smart ticketing. We intend to continue our growth into new technology fields, consistent with our mission to create value through our innovations and to make those technologies available through the shipment of products, the provisioning of services,roadmap, as well as our licensing business models. Key to our efforts continues to be hiring and retaining world-class inventors, scientists and engineers to lead the development and deployment of inventions and technology solutions for our fields of focus.

Ourgo-to-market strategy, is to continue to augment our patent license business model to provide additional technology, products and services while creating and leveraging strategic synergies to increase revenue. In supportdriven by the application-specific requirements of our strategy, we acquired four businesses in 2016 in the fields of mobile payments, smart ticketing, memory buffer chips and SerDes IP cores. On January 25, 2016, our Security division completed the acquisition of Smart Card Software, Ltd. (“SCS”), a privately-held company incorporated in the United Kingdom, for a pound sterling equivalent of $104.7 million in cash. Through this purchase we acquired two complementary businesses: Bell Identification Ltd., a leader in mobile payments, and Ecebs Ltd., a leading supplier of smart ticketing systems. We believe these businesses complement our security division by allowing us to extend our foundational security technology to offer differentiated, value-added security solutions to its customers.

On August 4, 2016, our Memory and Interfaces division completed the acquisition of all the assets of Inphi’s Memory Interconnect Business for $90 million in cash. The acquisition included product inventory, customer contracts, supply chain agreements and intellectual property. On August 5, 2016, our Memory and Interfaces division completed the acquisition of the assets of Semtech’s Snowbush IP group for $32 million in cash. Snowbush IP, formerly part of Semtech’s Systems Innovation Group, is a provider of silicon-proven, high-performance serial link solutions. We believe these acquisitions strengthen our market position for memory buffer chip products and bolster our SerDes and IP offerings enablingfocus markets. This not only allows us to better address the needs of the server, networking andserve our traditional data center market.and communications markets, but also to expand into new, fast-growing markets that demand the highest levels of performance and security, including automotive, artificial intelligence (AI), Internet of Things (IoT) and government.

Organization

We have organized the business into four operational units: (1) Memory and Interfaces, or MID, which focuses on the design, development, manufacturing through partnerships and licensing of technology and solutions that is related to memory and interfaces; (2) Security, or RSD, which focuses on the design, development, deployment and licensing of technologies for chip, system and in-field application security, anti-counterfeiting, smart ticketing and mobile payments; (3) Emerging Solutions, or ESD, which encompasses our long-term research and development efforts in the area of emerging technologies; and (4) Lighting, or RLD, which focuses on the design, development and licensing of technologies for advanced LED-based lighting solutions. As of December 31, 2016, MID and RSD met quantitative thresholds for disclosure as reportable segments. Results for ESD and RLD are shown under “Other.” For additional information concerning segment reporting, see Note 6, “Segments and Major Customers,” of Notes to Consolidated Financial Statements of this Form 10-K.


Revenue Sources


Our patented inventions and technology solutions are offered to our customers through patent, technology, software and IP core licenses, as well as product sales and services. Today, oura primary source of revenue is derived from patent licenses,our Architecture Licenses, through which we

provide our customers a license to use a certain portion of our broad worldwide portfolio of patented inventions. The license providesOur Architecture Licenses enable our customers with a defined right to use the licensed portion of our innovationsportfolio of patented inventions in the customer’s own digital electronics products, systems or services, as applicable.services. The licenses may also define the specific field of use where our customers may use or employ our inventions in their products. License agreements are structured with fixed or variable or a hybrid of fixed and variable royalty payments over certain defined periods ranging for periods of up to ten years. Leading consumer product, industrial, semiconductor and system companies such as AMD, Broadcom, Cisco, Freescale, Fujitsu, GE, IBM, Intel, LSI, Micron, Nanya, NVIDIA, Panasonic, Qualcomm, Renesas, Samsung, SK hynix, STMicroelectronics, Toshiba, Western Digital and Xilinx have licensed our

patents, the patents. The vast majority of which we have produced organically, for use in their own products. Royalties from patent licenses accounted for 73%, 84%our patents were secured through our internal research and 88% of our consolidated revenue for the years ended December 31, 2016, 2015 and 2014, respectively.development efforts.


We also offer our customers technology licenses to support the implementation and adoption of our technology in their products or services. Our customers include leading companies such as Eaton, GE, IBM, Panasonic, Qualcomm, Samsung, Sony and Toshiba. Our technology license offerings include a range of technologies for incorporation into our customers’ products and systems. We also offer a range of services as part of our technology licenses which can include know-how and technology transfer, product design and development, system integration, and other services. These technology license agreements may have both a fixed price (non-recurring) component and ongoing use fees and in some cases, royalties. Further, under technology licenses, our customers typically receive licenses to our patents necessary to implement these solutions in their products with specific rights and restrictions to the applicable patents elaborated in their individual contracts with us. Royalties

Revenues from technology licensesroyalties accounted for 6%41%, 5%56% and 4%74% of our consolidated revenue for the years ended December 31, 2016, 20152019, 2018 and 2014,2017, respectively.


The remainder of our revenue is product revenue, contract services and other revenue, which includes our product sales, IP core licenses, software licenses and related implementation, support and maintenance fees, and engineering services fees. The timing and amounts invoiced to customers can vary significantly depending on specific contract terms and can therefore have a significant impact on deferred revenue or account receivables in any given period. Contract and otherProduct revenue accounted for 21%33%, 11%17% and 8%9% of our consolidated revenue for the years ended December 31, 2016, 20152019, 2018 and 2014,2017, respectively. Contract and other revenue accounted for 27%, 27% and 17% of our consolidated revenue for the years ended December 31, 2019, 2018 and 2017, respectively.


Expenses


Cost of product revenue for 2019 increased approximately $8.9 million to $27.2 million from $18.3 million as compared to 2018 primarily due to increased cost of sales associated with higher sales of memory products.

Engineering expenses continue to play a key role in our efforts to maintain product innovations. Our engineering expenses for 2016 increased $40.52019 decreased $12.7 million as compared to the same period in 20152018 primarily due to the business acquisitions during 2016. This includes increaseddecreased amortization costs of $9.4 million, headcount related expenses of $12.9$3.9 million, increased cost of sales associated with sales of memory and security products and engineering services of $10.3 million (which includes $2.3 million related to the purchase accounting adjustment for inventory fair value step-up from the acquisition of the Memory Interconnect Business), increased amortizationallocated information technology costs of $7.0$1.6 million increased expenses related to software design tools of $3.7 million, increasedand stock-based compensation expense of $2.4 million, increased consulting costs of $2.5$1.5 million, offset by decreased prototypingincreased facilities costs of $0.5$2.1 million (primarily due to the adoption of the New Leasing Standard beginning in 2019 as discussed below), retention bonus accrual related to acquisitions of $2.0 million and engineering development tool costs of $1.2 million.


Sales, general and administrative expenses for 20162019 increased $24.6$0.2 million as compared to the same period in 20152018 primarily due to the business acquisitions during 2016. This includes increased headcount related expenses of $6.1 million, increased amortization costs of $5.0 million, various acquisition related costs of $3.1 million, increased stock-based compensation expense of $3.5$6.3 million increasedprimarily due to the termination of the former chief executive officer at the end of June 2018, acquisition and divestiture related costs of $5.2 million and facilities costs of $2.6 million (primarily due to the adoption of the New Leasing Standard beginning in 2019 as discussed below), offset by decreased headcount related expenses of $3.8 million, amortization cost of $2.9 million, depreciation expense of $1.8 million, sales and marketing costs of $1.2 million, travel expenses of $1.2 million, consulting costs of $2.8$1.0 million, increased facilitiesbonus accrual expense of $1.0 million and recruiting costs of $1.4 million and increased travel costs of $1.3$0.6 million.

Intellectual Property

As of December 31, 2016, our semiconductor, lighting, security and other technologies are covered by 1,989 U.S. and foreign patents. Additionally, we have 646 patent applications pending. Some of the patents and pending patent applications are derived from a common parent patent application or are foreign counterpart patent applications. We have a program to file applications for and obtain patents in the United States and in selected foreign countries where we believe filing for such protection is appropriate and would further our overall business strategy and objectives. In some instances, obtaining appropriate levels of protection may involve prosecuting continuation and counterpart patent applications based on a common parent application. We believe our patented innovations provide our customers with the ability to achieve improved performance, lower risk, greater cost-effectiveness and other benefits in their products and services.


Trends
There are a number of trends that may have a material impact on us in the future, including but not limited to, the evolution of memory and SerDes technology, adoption of mobile payment, smart ticketing and security solutions, adoption of LEDs in edge-lit general lighting, the use and adoption of our inventions or technologies generally, industry consolidation, and global economic conditions with the resulting impact on sales of consumer electronic systems. In addition, as discussed under “Results of Operations” below, our adoption of the New Revenue Standard will have a significant impact on our revenue trends as compared to periods prior to 2018 in which we reported revenue under ASC 605.

We have a high degree of revenue concentration. Our top five customers for each reporting period represented approximately 63%46% of our revenue for 20162019 as compared to 65%49% in 20152018 and 62%55% in 2014. For 2016, 2015 and 2014, revenue from Micron, Samsung and SK hynix each accounted for 10% or more of our total revenue. While we expect Samsung, SK

hynix and Micron to2017. The particular customers that account for a significant portion of our ongoing licensing revenue, the particular customers which account forsuch revenue concentration have varied from period-to-period as a result of the addition of new contracts, expiration of existing contracts, renewals of existing contracts, industry consolidation and the volumes and prices at which the customers have recently sold to their customers. These variations are expected to continue in the foreseeable future.


Our revenue from companies headquartered outside of the United States accounted for approximately 64%40% in 20162019 as compared to 60%44% in 20152018 and 63%58% in 2014.2017. We expect that revenue derived from international customers will continue to represent a significant portion of our total revenue in the future. To date, the majority of the revenue from international customers has been denominated in U.S. dollars. However, to the extent that such customers’ sales to their customers are not denominated in U.S. dollars, any revenue that we receive as a result of such sales could be subject to fluctuations in currency exchange rates. In addition, if the effective price of licensed products sold by our foreign customers were to increase as a result of fluctuations in the exchange rate of the relevant currencies, demand for licensed products could fall, which in turn would reduce our revenue. We do not use financial instruments to hedge foreign exchange rate risk. For additional information concerning international revenue, seerefer to Note 6,7, “Segments and Major Customers,” of Notes to Consolidated Financial Statements of this Form 10-K.


Our licensing cycle for new licensees as well as renewals for existing licensees is lengthy, costly and unpredictable without any degree of certainty. We may incur costs in any particular period before any associated revenue stream begins, if at all. Our lengthy license negotiation cycles could make our future revenue difficult to predict because we may not be successful in entering into licenses with our customers in the amounts projected, or on our anticipated timelines.


The semiconductor industry is intensely competitive and highly cyclical, limiting our visibility with respect to future sales. To the extent that macroeconomic fluctuations negatively affect our principal customers, the demand for our products and technology may be significantly and adversely impacted and we may experience substantial period-to-period fluctuations in our operating results.


The royalties we receive from our semiconductor customers are partly a function of the adoption of our technologies by systemsystems companies. Many systemsystems companies purchase semiconductors containing our technologies from our customers and do not have a direct contractual relationship with us. Our customers generally do not provide us with details as to the identity or volume of licensed semiconductors purchased by particular system companies. As a result, we face difficulty in analyzing the extent to which our future revenue will be dependent upon particular system companies.

Global demand for effective security technologies continues to increase. In particular, highly integrated devices such as smart phones are increasingly used for applications requiring security such as mobile payments, corporate information and user data. Our RSD operating segment is primarily focused on positioning its DPA countermeasures, CryptoMedia™, CryptoFirewall™ and CryptoManager™ technology solutions, and the introductionCost of in-field applications mobile payments and smart ticketing solutions to our offerings to capitalize on these trends and growing adoption among technology partners and customers.

Engineering costsproduct revenue as well as sales, general and administrative expenses in the aggregate and as a percentage of revenue increased in 20162019 as compared to the prior year. Engineering costs in the aggregate and as a percentage of revenue decreased in 2019 as compared to the prior year. In the near term, we expect these costs in the aggregate to be higher as we intend to continue to make investments in the infrastructure and technologies required to increase our product innovation in semiconductor, security mobile payments, smart cards and other technologies, including costs related to the various acquisitions.technologies. In addition, while we have not been involved in material litigation since 2014, to the extent litigation is again necessary, our expectations on the amount and timing of any future general and administrative costs isare uncertain.


As a part of our overall business strategy, from time to time, we evaluate businesses and technologies for potential acquisition that are aligned with our core business and designed to supplement our growth, including the 2019 acquisitions of SCS, the assets of the Snowbush IP groupNorthwest Logic and the Memory Interconnect Business.Secure Silicon IP and Protocols business from Verimatrix, formerly Inside Secure. Similarly, we evaluate our current businesses and technologies that are not aligned with our core business for potential divestiture.divestiture, such as the sale of our Payments and Ticketing businesses to Visa International Service Association in 2019. We expect to continue to evaluate and potentially enter into strategic acquisitions or divestitures which may adversely impact our business and operating results.

Results of Operations
On January 1, 2018, we adopted ASC 606. Consistent with the modified retrospective adoption method, our results of operations for the period prior to our adoption of ASC 606 remain unchanged as revenue for the year ended December 31, 2017 was recognized under ASC 605. Therefore, the period is not directly comparable.
The adoption of ASC 606 limits the comparability of revenue and certain expenses presented in the results of operations for the years ended December 31, 2019 and 2018, when compared to the same period in 2017.
The following table sets forth, for the periods indicated, the percentage of total revenue represented by certain items reflected in our consolidated statements of operations:
Years Ended December 31,Years Ended December 31,
2016 2015 20142019 2018 2017
Revenue:          
Royalties78.6 % 88.6 % 91.6 %40.5 % 56.4 % 73.7 %
Product revenue32.6 % 16.7 % 9.3 %
Contract and other revenue21.4 % 11.4 % 8.4 %26.9 % 26.9 % 17.0 %
Total revenue100.0 % 100.0 % 100.0 %100.0 % 100.0 % 100.0 %
Operating costs and expenses:          
Cost of revenue*19.9 % 15.3 % 14.1 %
Cost of product revenue*12.1 % 7.9 % 6.1 %
Cost of contract and other revenue10.8 % 15.3 % 14.1 %
Research and development*38.6 % 37.5 % 37.1 %70.0 % 68.5 % 37.9 %
Sales, general and administrative*28.3 % 23.8 % 25.2 %46.5 % 44.9 % 28.2 %
Restructuring charges % 1.2 % 0.0 %
Impairment of in-process research and development intangible asset5.4 %  %  %
Change in contingent consideration liability(2.0)%  %  %
Restructuring and other charges3.9 % 1.0 %  %
Loss on divestiture3.3 %  %  %
Gain from sale of intellectual property % (1.2)% (1.2)% %  % (0.1)%
Gain from settlement(0.2)% (0.7)% (0.6)%
Total operating costs and expenses90.0 % 75.9 % 74.6 %146.6 % 137.6 % 86.2 %
Operating income10.0 % 24.1 % 25.4 %
Interest income and other income, net0.5 % 0.3 % (0.1)%
Operating income (loss)(46.6)% (37.6)% 13.8 %
Interest income and other income (expense), net12.2 % 14.1 % 0.4 %
Loss on extinguishment of debt %  % (0.3)%
Interest expense(3.8)% (4.2)% (8.4)%(4.4)% (7.0)% (3.5)%
Interest and other income (expense), net(3.3)% (3.9)% (8.5)%7.8 % 7.1 % (3.4)%
Income before income taxes6.7 % 20.2 % 16.9 %
Provision for (benefit from) income taxes4.7 % (51.0)% 8.1 %
Net income2.0 % 71.2 % 8.8 %
Income (loss) before income taxes(38.8)% (30.5)% 10.4 %
Provision for income taxes1.5 % 37.8 % 16.2 %
Net loss(40.3)% (68.3)% (5.8)%

* Includes stock-based compensation:          
Cost of revenue0.0% 0.0% 0.0%
Cost of product revenue0.0% 0.0% 0.0%
Research and development2.7% 2.3% 2.4%4.9% 5.4% 3.1%
Sales, general and administrative3.5% 2.8% 2.5%6.9% 4.0% 3.9%
Segment Results

 Years Ended December 31, 2018 to 2019 2017 to 2018
 2019 2018 2017 Change Change
 (Dollars in millions)    
Total Revenue         
Royalties$90.8
 $130.5
 $289.6
 (30.4)% (55.0)%
Product revenue73.0
 38.7
 36.5
 88.6 % 6.0 %
Contract and other revenue60.2
 62.0
 67.0
 (2.9)% (7.4)%
Total revenue$224.0
 $231.2
 $393.1
 (3.1)% (41.2)%
Royalty Revenue from the MID reportable segment increased
Our royalty revenue, which includes patent and technology license royalties, decreased approximately $17.8$39.7 million to $239.8$90.8 million for the year ended December 31, 20162019 from $222.0$130.5 million for 2018. The decrease was due primarily to the timing of renewals and the related structure of architecture license agreements which include both fixed and variable components.
Our royalty revenue decreased approximately $159.1 million to $130.5 million for the year ended December 31, 2015.2018 from $289.6 million for 2017. The increasedecrease was due primarily to the change in revenue recognition whereby we no longer recognize revenue at the time billings become due to salesand collectable. Upon adoption of memory products, includingASC 606 in the first quarter of 2018, we now recognize revenue fromat the Memory and Interfaces Business and various new development projects, higher royaltyinception of certain fixed-fee licensing arrangements when our performance obligations are met. Under the previous revenue recognized from SK hynix and Xilinx, offset by lower royaltyrecognition standard (ASC 605), our revenue from AMD, IBM and Renesas.
Segment operating income from the MID reportable segment decreased approximately $2.8 million to $171.4 million for the year ended December 31, 2016 from $174.2 million for the year ended December 31, 2015. The decrease was primarilywould have been higher.
With changes in revenue recognition due to an increasethe adoption of ASC 606 in cost of sales related to sales of memory products and increased headcount related costs due to higher number of employees in 20162018, our royalty revenue for 2018 was significantly lower than that for 2017 primarily due to the acquisitionchange from the adoption of ASC 606 as noted above. This accounting change will not impact billings or the cash flow from these arrangements. Furthermore, we may experience greater variability in quarterly and annual revenue in future periods as a result of the assets of the Snowbush IP group and Memory Interconnect Business.revenue accounting treatment applied to future fixed-fee licensing arrangements.
Revenue from the RSD reportable segment increased approximately $25.7 million to $76.2 million for the year ended December 31, 2016 from $50.5 million for the year ended December 31, 2015. The increase was primarily due to higher revenue from security technology development projects, including revenue from the acquisition of SCS, and higher royalty

revenue from Qualcomm, Xilinx and various other customers, offset by lower royalty revenue from Nagravision, Renesas and STMicroelectronics.
Segment operating income from the RSD reportable segment increased approximately $2.9 million to $24.3 million for the year ended December 31, 2016 from $21.4 million for the year ended December 31, 2015. The increase was primarily due to increase in revenue as discussed above, partially offset by increased headcount related costs due to higher number of employees in 2016 primarily due to the SCS acquisition.
Revenue from the Other segment decreased approximately $3.2 million to $20.6 million for the year ended December 31, 2016 from $23.8 million for the year ended December 31, 2015. The decrease was primarily due to decreased sales of light guides and decreased revenue from lighting technology development projects.
Segment operating loss from the Other segment increased approximately $1.5 million to $9.8 million for the year ended December 31, 2016 from $8.3 million for the year ended December 31, 2015. The increase was primarily due to decreased revenue as discussed above and lack of gain from sale of intellectual property in 2016.
Revenue from the MID reportable segment decreased approximately $4.3 million to $222.0 million for the year ended December 31, 2015 from $226.3 million for the year ended December 31, 2014. The decrease was primarily due to lower royalty revenue from AMD, Nanya, NVIDIA, Renesas and STMicroelectronics, offset by higher royalty revenue from IBM and SK hynix.
Segment operating income from the MID reportable segment decreased approximately $11.3 million to $174.2 million for the year ended December 31, 2015 from $185.5 million for the year ended December 31, 2014. The decrease was primarily due to decrease in revenue as discussed above and increased expenses related to software design tools and increased prototyping costs.
Revenue from the RSD reportable segment increased approximately $1.2 million to $50.5 million for the year ended December 31, 2015 from $49.3 million for the year ended December 31, 2014. The increase was primarily due to higher revenue from security products, offset by lower royalty revenue from Qualcomm, STMicroelectronics and a smartphone and tablet manufacturer.
Segment operating income from the RSD reportable segment remained relatively flat at $21.4 million for the year ended December 31, 2015 as compared to $21.7 million for the year ended December 31, 2014.
Revenue from the Other segment increased approximately $2.9 million to $23.8 million for the year ended December 31, 2015 from $20.9 million for the year ended December 31, 2014. The increase was primarily due to increased lighting technology development projects and sales of light guides.
Segment operating loss from the Other segment decreased approximately $4.9 million to $8.3 million for the year ended December 31, 2015 from $13.2 million for the year ended December 31, 2014. The decrease was primarily due to increase in revenue as discussed above and lower prototyping costs.
 Years Ended December 31, 2015 to 2016 2014 to 2015
 2016 2015 2014 Change Change
 (Dollars in millions)    
Total Revenue         
Royalties$264.6
 $262.4
 $271.5
 0.8% (3.4)%
Contract and other revenue72.0
 33.9
 25.1
 112.6% 35.3 %
Total revenue$336.6
 $296.3
 $296.6
 13.6% (0.1)%
Royalty Revenue
Patent Licenses
Our patent royalties decreased approximately $4.5 million to $244.4 million for the year ended December 31, 2016 from $248.9 million for the same period in 2015. The decrease was primarily due to lower royalty revenue from AMD, IBM, Renesas and STMicroelectronics, offset by higher royalty revenue recognized from Qualcomm, SK hynix and Xilinx. Of the $244.4 million patent royalties for the year ended December 31, 2016, $21.2 million is related to past royalty revenue from settlement of past legal proceedings with SK Hynix and Micron.

Our patent royalties decreased approximately $12.0 million to $248.9 million for the year ended December 31, 2015 from $260.9 million for the same period in 2014. The decrease in 2015 was primarily due to lower royalty revenue recognized from AMD, NVIDIA, Renesas, STMicroelectronics and a smartphone and tablet manufacturer, offset by higher royalty revenue from IBM and SK hynix. Of the $248.9 million patent royalties for the year ended December 31, 2015, $86.0 million is related to past royalty revenue from settlement of past legal proceedings with SK hynix and Micron.
We are continuously in negotiations for licenses with prospective customers. We expect patent royalties will continue to vary from period to period based on our success in adding new customers, renewing or extending existing agreements, as well as the level of variation in our customers'customers’ reported shipment volumes, sales price and mix, offset in part by the proportion of customer payments that are fixed or hybrid in nature.
Technology Licenses
Royalties from technology licenses increased approximately $6.7 million to $20.2 million for the year ended December 31, 2016 from $13.5 million for the same period in 2015. The increase was primarily due to higher royalties from Eaton and various security technology license revenue, offset by lower royalties from Nagravision.
Royalties from technology licenses increased approximately $2.9 million to $13.5 million for the year ended December 31, 2015 from $10.6 million for the same period in 2014. The increase was primarily due to higher royalties from security and lighting technology license revenue, offset by lower royalties from XDR DRAM associated with decreased shipments of the Sony PlayStation®3 product.
In the future, we We also expect that our technology royalties will continue to vary from period to period based on our customers’ shipment volumes, sales prices, and product mix.

RoyaltyProduct Revenue by Reportable Segment

RoyaltyProduct revenue consists of revenue from the MID reportable segment, which includes patentsale of memory and technology license royalties, decreasedsecurity products in 2019. Product revenue increased approximately $5.0$34.3 million to $212.7$73.0 million for the year ended December 31, 20162019 from $217.7$38.7 million for the same period in 2015.2018. The decreaseincrease was primarily due to lower royaltygreater market share gains of our memory interface chips.
Product revenue from AMD, IBM and Renesas, offset by higher royalty revenue recognized from SK hynix and Xilinx.
Royaltyconsisted of revenue from the RSD reportable segment, which includes patentsale of memory, security and technology license royalties,lighting products in 2018 and 2017. Product revenue increased $5.5approximately $2.2 million to $46.9$38.7 million for the year ended December 31, 20162018 from $41.4$36.5 million for the same period in 2015.2017. The increase was primarily due to higher royalty revenue from Qualcomm, Xilinx and various other customers,sales of memory products, partially offset by lower royaltysales of lighting products, as a result of closing our lighting division in the first quarter of 2018.
We believe that product revenue from Nagravision, Renesas and STMicroelectronics.
Royalty revenuewill increase in 2020, mainly from the Other segment increased $1.8 millionsale of our memory products. Our ability to $5.1 million for the year ended December 31, 2016continue to grow product revenue is dependent on, among other things, our ability to continue to obtain orders from $3.3 million for the same period in 2015. The increase was duecustomers and our ability to increased royalties from technology licenses associated with increased shipments of lighting products.
Royalty revenue from the MID reportable segment decreased approximately $5.8 million to $217.7 million for the year ended December 31, 2015 from $223.5 million for the same period in 2014. The decrease was primarily due to lower royalty revenue from AMD, Nanya, NVIDIA, Renesas and STMicroelectronics, offset by higher royalty revenue from IBM and SK hynix.
Royalty revenue from the RSD reportable segment decreased approximately $4.3 million to $41.4 million for the year ended December 31, 2015 from $45.7 million for the same period in 2014. The decrease was primarily due to lower royalty revenue from Qualcomm, STMicroelectronics and a smartphone and tablet manufacturer.
Royalty revenue from the Other segment increased $1.0 million to $3.3 million for the year ended December 31, 2015 from $2.3 million for the same period in 2014. The increase was due to increased royalties from technology licenses associated with increased shipments of lighting products.meet our customers’ demands.
Contract and Other Revenue
Contract and other revenue consists of revenue from technology development and sale of memory, security and lighting products.projects. Contract and other revenue increaseddecreased approximately $38.2$1.8 million to $72.0$60.2 million for the year ended December 31, 20162019 from $33.8$62.0 million for the same period in 2015.2018. The increasedecrease was primarily due to saleslower revenue associated with our Payments and Ticketing businesses, which was divested in the fourth quarter of memory products, including revenue from the Snowbush IP group and the Memory Interconnect Business, and increased security technology development projects, including revenue from the acquisition of SCS,2019, offset by decreased sales of light guides.


growth experienced in our Silicon IP business.
Contract and other revenue increaseddecreased approximately $8.8$5.0 million to $33.8$62.0 million for the year ended December 31, 20152018 from $25.0$67.0 million for the same period in 2014.2017. The increasedecrease was primarily due to increasedlower revenue from security technology development projectsvarious memory and products as well as lighting technology development projects, and sales of light guides,partially offset by lowerhigher revenue from the sale of selected intellectual property.various security technology development projects.


We believe that contract and other revenue will fluctuate over time based on our ongoing technology development contractual requirements, the amount of work performed, the timing of completing engineering deliverables, and the changes to work required, as well as new technology development contracts booked in the futurefuture.
Cost of product revenue:
 Years Ended December 31, 2018 to 2019 2017 to 2018
 2019 2018 2017 Change Change
 (Dollars in millions)    
Cost of product revenue$27.2
 $18.3
 $23.8
 48.4% (23.1)%

Cost of product revenue are costs attributable to the sale of memory and security products. Cost of product sales.revenue also included costs attributable to the sale of lighting products in 2018 and 2017.
Contract and Other Revenue by Reportable Segments
Contract and other revenue from the MID reportable segment increased $22.9 million to $27.2 million forFor the year ended December 31, 2016 from $4.3 million for the same period in 2015,2019 as compared to 2018, cost of product revenue increased 48.4% primarily due to increased cost of sales associated with higher sales of memory products, including revenue from the Snowbush IP group and the Memory Interconnect Business, and various new development projects. Contract and other revenue from the RSD reportable segment increased approximately $20.2 million to $29.3 million forproducts.
For the year ended December 31, 2016 from $9.1 million for the same period in 2015, primarily due2018 as compared to higher2017, cost of product revenue from security technology development projects, including revenue from the acquisition of SCS. Contract and other revenue from the Other segment decreased approximately $5.0 million for the year ended December 31, 2016 from $20.5 million for the same period in 2015,23.1% primarily due to decreased cost of sales associated with the closure of the lighting division announced in the first quarter of 2018, offset by increased cost of sales associated with higher sales of light guides and decreasedmemory products.
In the near term, we expect costs of product revenue from lighting technology development projects.
Contract and other revenue from the MID reportable segment increased approximately $1.4 million to $4.3 million for the year ended December 31, 2015 from $2.9 million for the same period in 2014, primarily due to new technology development contracts in 2015. Contract and other revenue from the RSD reportable segment increased approximately $5.5 million to $9.1 million for the year ended December 31, 2015 from $3.6 million for the same period in 2014, primarily due tobe higher revenue from security products. Contract and other revenue from the Other segment increased approximately $1.9 million to $20.5 million for the year ended December 31, 2015 from $18.6 million for the same period in 2014, primarily due to increased lighting technology development projects andas we expect higher sales of light guides.
our various products in 2020 as compared to 2019.
Engineering costs:
Years Ended December 31, 2015 to 2016 2014 to 2015Years Ended December 31, 2018 to 2019 2017 to 2018
2016 2015 2014 Change Change2019 2018 2017 Change Change
(Dollars in millions)    (Dollars in millions)    
Engineering costs                  
Cost of revenue$37.4
 $22.7
 $19.1
 64.8% 19.0 %
Cost of contract and other revenue$9.9
 $11.7
 $20.3
 (15.4)% (42.1)%
Amortization of intangible assets29.7
 22.6
 22.9
 31.2% (1.1)%14.3
 23.7
 35.1
 (39.6)% (32.4)%
Total cost of revenue67.1
 45.3
 42.0
 48.0% 8.1 %
Total cost of contract and other revenue24.2
 35.4
 55.4
 (31.6)% (36.1)%
Research and development120.6
 104.3
 102.8
 15.7% 1.5 %145.8
 145.7
 136.9
 0.0 % 6.4 %
Stock-based compensation9.2
 6.8
 7.2
 35.5% (6.3)%11.0
 12.6
 12.2
 (12.3)% 3.3 %
Total research and development129.8
 111.1
 110.0
 16.9% 1.0 %156.8
 158.3
 149.1
 (1.0)% 6.2 %
Total engineering costs$196.9
 $156.4
 $152.0
 25.9% 2.9 %$181.0
 $193.7
 $204.5
 (6.6)% (5.3)%
Engineering costs are allocated between cost of contract and other revenue and research and development expenses. Cost of contract and other revenue reflects the portion of the total engineering costs which are specifically devoted to individual customer development and support services costs of memory, security and lighting products sold as well as amortization expense related to various acquired intellectual property for patent licensing. The balance of engineering costs, incurred for the development of applicable technologies, is charged to research and development. In a given period, the allocation of engineering costs between these two components is a function of the timing of the development and implementation schedules of individual customer contracts.
For the year ended December 31, 20162019 as compared to the same period in 2015,2018, total engineering costs increased 25.9%decreased 6.6% primarily due to the business acquisitions during 2016. This includes increaseddecreased amortization costs of $9.4 million, headcount related expenses of $12.9$3.9 million, increased cost of sales associated with sales of memory and security products and engineering services of $10.3 million (which includes $2.3 million related to the purchase accounting adjustment for inventory fair value step-up from the acquisition of the Memory Interconnect Business), increased amortizationallocated information technology costs of $7.0$1.6 million increased expenses related to software design tools of $3.7 million, increasedand stock-based compensation expense of $2.4 million, increased consulting costs of $2.5$1.5 million, offset by decreased prototypingincreased facilities costs of $0.5$2.1 million as discussed below, retention bonus accrual related to acquisitions of $2.0 million and engineering development tool costs of $1.2 million.
On January 1, 2019, we adopted the New Leasing Standard using the alternative transition method. In accordance with the New Leasing Standard, we were required to derecognize the Sunnyvale and Ohio facilities as imputed facility obligations (as accounted for under the previous leasing guidance) and recognize these facilities as operating leases. This change resulted in no longer recognizing interest expense associated with these imputed facility lease obligations, but instead, recognizing lease expense that was included in operating costs and expenses. For additional information on the impact of the new accounting standard on our leases, see Note 3, “Recent Accounting Pronouncements” and Note 10, “Leases,” of Notes to Consolidated Financial Statements of this Form 10-K.

For the year ended December 31, 20152018 as compared to the same period in 2014,2017, total engineering costs increased 2.9%decreased 5.3% primarily due to increased expenses related to software design tools of $3.5 million, increased headcount related expenses of

$2.1 million, increased bonus accrual expense of $1.5 million and increased cost of sales associated with increased sales of light guides and security products and engineering services of $1.5 million, offset by decreased accrual of retention bonuses of $1.5 million, decreased amortization costs of $1.5$11.4 million, prototyping costs of $1.8 million and decreased equipment and software maintenancedepreciation expense of $1.4 million, offset by increased consulting expenses of $1.2 million, engineering development tool costs of $0.7$1.0 million, allocated information technology costs of $1.1 million and stock-based compensation expense of $0.4 million.
In the near term, we expect engineering costs to be higher as we continue to make investments in the infrastructure and technologies required to maintain our product innovation in semiconductor, lighting, security and other technologies, including costs related to the acquisitions throughout the year.technologies.
Sales, general and administrative costs:
Years Ended December 31, 2015 to 2016 2014 to 2015Years Ended December 31, 2018 to 2019 2017 to 2018
2016 2015 2014 Change Change2019 2018 2017 Change Change
(Dollars in millions)    (Dollars in millions)    
Sales, general and administrative costs                  
Sales, general and administrative costs$83.3
 $62.3
 $67.3
 33.8% (7.5)%$88.7
 $94.8
 $95.8
 (6.4)% (1.1)%
Stock-based compensation11.8
 8.3
 7.5
 42.6% 10.7 %15.4
 9.1
 15.1
 68.8 % (39.6)%
Total sales, general and administrative costs$95.1
 $70.6
 $74.8
 34.9% (5.6)%$104.1
 $103.9
 $110.9
 0.2 % (6.3)%
Sales, general and administrative expenses include expenses and costs associated with trade shows, public relations, advertising, litigation, general legal, insurance and other sales, marketing and administrative efforts. Litigation expenses have historically been a significant portion of our sales, general and administrative expenses. Consistent with our business model, our licensing, sales and marketing activities aim to develop or strengthen relationships with potential new and current customers. In addition, we work with current customers through marketing, sales and technical efforts to drive adoption of their products that use our innovations and solutions, by system companies. Due to the long business development cycles we face and the semi-fixed nature of sales, general and administrative expenses in a given period, these expenses generally do not correlate to the level of revenue in that period or in recent or future periods.
For the year ended December 31, 20162019 as compared to 2015,2018, total sales, general and administrative costs increased 34.9%0.2% primarily due to the business acquisitions during 2016. This includes increased headcount related expenses of $6.1 million, increased amortization costs of $5.0 million, various acquisition related costs of $3.1 million, increased stock-based compensation expense of $3.5$6.3 million increasedprimarily due to the termination of the former chief executive officer at the end of June 2018, acquisition and divestiture related costs of $5.2 million and facilities costs of $2.6 million (primarily due to the adoption of the New Leasing Standard beginning in 2019 as discussed above), offset by decreased headcount related expenses of $3.8 million, amortization cost of $2.9 million, depreciation expense of $1.8 million, sales and marketing costs of $1.2 million, travel expenses of $1.2 million, consulting costs of $2.8$1.0 million, increased facilitiesbonus accrual expense of $1.0 million and recruiting costs of $1.4 million and increased travel costs of $1.3$0.6 million.
For the year ended December 31, 20152018 as compared to 2014,2017, total sales, general and administrative costs decreased 5.6%6.3% primarily due to decreased stock-based compensation expense of $6.0 million primarily due to the termination of the former chief executive officer at the end of June 2018, consulting costs of $3.1$1.1 million decreased depreciation expense of $1.3 million, decreased software and equipment maintenancesales and marketing costs of $0.9 million and decreased litigation costs of $0.5$1.2 million, offset by increased headcount related expensesfacilities costs of $0.9$1.0 million and increased stock-based compensation expenserecruiting costs of $0.8$0.6 million.
In the future, sales, general and administrative costs will vary from period to period based on the trade shows, advertising, legal, acquisition and other sales, marketing and administrative activities undertaken, and the change in sales, marketing and administrative headcount in any given period. In the near term, we expect our sales, general and administrative costs to be higher due to the acquisitions throughout the year.remain relatively flat.
Restructuring and other charges:
 Years Ended December 31, 2015 to 2016 2014 to 2015
 2016 2015 2014 Change Change
 (Dollars in millions)    
Restructuring charges$
 $3.6
 $0.0
 (100.0)% NM*
 Years Ended December 31, 2018 to 2019 2017 to 2018
 2019 2018 2017 Change Change
 (Dollars in millions)    
Restructuring and other charges$8.8
 $2.2
 $
 NM* 100.0%

*NM — percentage is not meaningful
During 2016, we did not initiate any restructuring programs.
During 2015,2019, we initiated a restructuring program to reduce overall corporate expenses which is expected to improve future profitability by reducing spending on research and development efforts and sales, general and administrative programs (the “2019 Plan”). Additionally, we recorded other severance related charges of $1.4 million during the third quarter of 2019.

During 2018, we closed our lighting division and refining some ofmanufacturing operations in Brecksville, Ohio. We believed that such business was not core to our researchstrategy and development efforts.growth objectives. As a result, of the restructuring program, we recorded a charge of $3.6$2.2 million during 2015 related primarily to the reduction in workforce.employee terminations and severance costs, and facility related costs.

During 2017, we did not initiate any restructuring programs.
Refer to Note 15,18, “Restructuring Charges,” of Notes to Consolidated Financial Statements of this Form 10-K for further discussion.

Impairment of in-process research and development intangible asset:
 Years Ended December 31, 2015 to 2016 2014 to 2015
 2016 2015 2014 Change Change
 (Dollars in millions)    
Impairment of in-process research and development intangible asset$18.3
 $
 $
 100.0% 0.0%
During the fourth quarter of 2016, we recorded a charge of $18.3 million related the impairment of in-process research and development intangible asset acquired in the acquisition of Snowbush IP. The impairment of this intangible asset resulted from a delay in the market served by this initiative. This delay will not impact the short-term revenue expectations but will impact our revenue expectations several years into the future. This impairment was partially offset by a $6.8 million reduction of acquisition purchased consideration related to this product line.
During 2015 and 2014, we did not record a charge for the impairment of any intangible assets or goodwill.
Refer to Note 5 “Intangible Assets and Goodwill,Other Charges,” of Notes to Consolidated Financial Statements of this Form 10-K for further discussion.
Change in contingent consideration liability:Loss on divestiture:
 Years Ended December 31, 2015 to 2016 2014 to 2015
 2016 2015 2014 Change Change
 (Dollars in millions)    
Change in contingent consideration liability$(6.8) $
 $
 100.0% 0.0%
 Years Ended December 31, 2018 to 2019 2017 to 2018
 2019 2018 2017 Change Change
 (Dollars in millions)    
Loss on divestiture$7.4
 $
 $
 100.0% %
During the fourth quarter of 2016, we recorded a reduction in our contingent consideration liability of $6.8 million resulting in a gain in our Consolidated Statements of Operations of this Form 10-K. See the “Impairment of in-process research and development intangible asset” section discussed above for further details.
Gain from sale of intellectual property:
 Years Ended December 31, 2015 to 2016 2014 to 2015
 2016 2015 2014 Change Change
 (Dollars in millions)    
Gain from sale of intellectual property$
 $3.7
 $3.5
 (100.0)% 4.4%
During 2016, we did not sell any of our patent assets.
During 2013, we sold portfolios of our patent assets covering lighting technologies. As part of these transactions, we received an initial upfront payment and expect to receive subsequent payments when the purchaser of the patents is successful in licensing that portfolio. During 2015 and 2014, we received $3.7 million and $3.4 million, respectively, from the purchaser of the patents related to this transaction which was recorded as gain from sale of intellectual property. During 2016, we did not receive any payment from the purchaser of the patents related to this transaction.
During 2014, we sold portfolios of our patent assets covering wireless and other technologies.
Gain from settlement:
 Years Ended December 31, 2015 to 2016 2014 to 2015
 2016 2015 2014 Change Change
 (Dollars in millions)    
Gain from settlement$0.6
 $2.0
 $2.0
 (71.6)% 0.0%
The settlements with SK hynix and Micron are multiple element arrangements for accounting purposes. For a multiple element arrangement, we are required to determine the fair value of the elements. We considered several factors in determining the accounting fair value of the elements of the settlement with SK hynix and the settlement with Micron which included a third party valuation using an income approach (the “SK hynix Fair Value” and "Micron Fair Value", respectively). The total gain from settlement related to the settlements with SK hynix and Micron was $1.9 million and $3.3 million, respectively. As of the end of the second quarter of 2016,2019, we entered into a share purchase agreement with Visa International Service Association (the “Purchaser”), pursuant to which the total gain from settlement relatedPurchaser had agreed to acquire all of the settlements with SK hynixoutstanding shares of our subsidiary, Smart Card Software Limited, which was comprised of our Payments and Micron has been fully recognized. DuringTicketing businesses. The decision to sell these businesses reflects our ongoing review of our business to focus on products and offerings that are core to our semiconductor business.
Consequently, we measured these businesses at the yearslower of their carrying value or fair value less any costs to sell, and subsequently recognized a loss of approximately $7.4 million during the year ended December 31, 2016, 20152019.
During 2018 and 2014,2017, we recognized $0.6 million, $2.0 million anddid not record a charge for loss on divestiture.

$2.0 million as gain from settlement, which represents the portion of the SK hynix Fair Value and Micron Fair Value of the cash consideration allocated to the resolution of the antitrust litigation settlements. Refer to Note 18, “Agreements with SK hynix and Micron,17, “Divestiture,” of Notes to Consolidated Financial Statements of this Form 10-K for further discussion.
Interest and other income (expense), net:
Years Ended December 31, 2015 to 2016 2014 to 2015Years Ended December 31, 2018 to 2019 2017 to 2018
2016 2015 2014 Change Change2019 2018 2017 Change Change
(Dollars in millions)    (Dollars in millions)    
Interest income and other income (expense), net$1.7
 $1.2
 $(0.3) 42.2 % NM*
$27.4
 $32.6
 $1.4
 (16.1)% NM*
Loss on extinguishment of debt
 
 (1.1) 0.0 % (100.0)%
Interest expense(12.7) (12.4) (24.8) 2.7 % (50.0)%(9.9) (16.3) (13.7) (39.5)% 18.7 %
Interest and other income (expense), net$(11.0) $(11.2) $(25.1) (1.6)% (55.4)%$17.5
 $16.3
 $(13.4) 7.2 % NM*

*NM — percentage is not meaningful
*    NM — percentage is not meaningful

Interest income and other income (expense), net, consists primarily of interest income of $20.4 million and $27.2 million for the years ended December 31, 2019 and 2018, respectively, due to the significant financing component of licensing agreements as a result of the adoption of the New Revenue Standard as of January 1, 2018. Interest income and other income (expense), net, also includes interest income generated from investments in high quality fixed income securities and any gains or losses from the re-measurement of our monetary assets or liabilities denominated in foreign currencies. Additionally, in 2014, during our review
Loss on extinguishment of debt relates to the extinguishment of a portion of the remaining fair value2018 Notes during 2017. Refer to Note 12, “Convertible Notes,” of our $0.6 million investment in the non-marketable equity securityNotes to Consolidated Financial Statements of a private company, based on the information provided by the private company, we determined that there was a decrease in the security's fair value. The fair value of the non-marketable equity security was determined based on an income approach, using level 3 fair value inputs, as it was deemed to be the most indicative of the security's fair value. Accordingly, we recorded an impairment chargethis Form 10-K for the entire remaining amount of $0.6 million related to our investment in the non-marketable equity security in 2014.additional details.
InterestBeginning January 1, 2019, interest expense for all periods disclosed primarily consists of interest expense associated with our imputed facility lease obligations on the Sunnyvale and Ohio facilities and non-cash interest expense related to the amortization of the debt discount and issuance costs on the 5%1.375% convertible senior notes due 20142023 (the “2014“2023 Notes”) and the 1.125% convertible senior notes due 2018 (the “2018 Notes”), as well as the coupon interest related to these notes. Interest expense increaseddecreased in 20162019 as compared to the same period in 20152018 primarily due to the 2018 Notes maturing in the third quarter of the 2018 Notes.2018. Interest expense decreasedincreased in 20152018 as compared to the same period in 20142017 primarily due to the repaymentfull year of interest expense related to the 2023 Notes offset by the maturing of the 20142018 Notes in the secondthird quarter of 2014.2018. We expect our non-cash interest expense to increase steadily as the notes reach maturity. Refer to Note 12, “Convertible Notes,” of Notes to Consolidated Financial Statements of this Form 10-K for additional details.
Prior to 2019, interest expense also included the interest expense associated with our imputed facility lease obligations on the Sunnyvale and Ohio facilities. For the years ended December 31, 2016, 2015,2018 and 2014,2017, we recognized $4.4 million, $4.5$4.3 million and $4.5$4.4 million, respectively, of interest expense in connection with the imputed financing obligations in our statements of operations. We expect our non-cashIn accordance with the New Leasing Standard, we were required to derecognize the Sunnyvale and Ohio facilities as imputed facility obligations (as accounted for under the previous leasing standard) and recognize these facilities as operating leases. This change resulted in no longer recognizing interest expense to increase steadily asassociated with these imputed facility lease obligations, but instead,


recognizing lease expense which would be included in operating costs and expenses. For additional information on the notes reach maturity. Seeimpact of the new accounting standard on our leases, see Note 3, “Recent Accounting Pronouncements” and Note 10, “Convertible Notes,“Leases,” of Notes to Consolidated Financial Statements of this Form 10-K for additional details.10-K.
Provision for (benefit from) income taxes:
Years Ended December 31, 2015 to 2016 2014 to 2015Years Ended December 31, 2018 to 2019 2017 to 2018
2016 2015 2014 Change Change2019 2018 2017 Change Change
(Dollars in millions) (Dollars in millions)    
Provision for (benefit from) income taxes$15.8
 $(151.2) $24.0
 NM* NM*
Provision for income taxes$3.4
 $87.3
 $63.9
 (96.1)% 36.8%
Effective tax rate69.9% (251.0)% 47.9% (3.9)% (123.6)% 155.8%    

*NM — percentage is not meaningful
Our effective tax rate for the year ended December 31, 20162019 was different from the U.S. statutory tax rate primarily due to incomethe full valuation allowance on the current year tax expense recognized from exercises and expiration of out-of-the-money fully vested shares from our equity incentive plans.loss. Our effective tax ratesrate for the year ended December 31, 20152018 was different from the U.S. statutory taxrate primarily due to the releaseestablishment of thea full valuation allowance on our U.S. federal and state deferred tax assets, offset by federal, state, and foreign taxes.assets. Our effective tax ratesrate for the yearsyear ended December 31, 2014 were2017 was different from the U.S. statutory tax rate primarily due to the valuation allowance on ourexpiring 2010 foreign tax credits and certain federal research and development credits, and the remeasurement of deferred taxes from 35% to 21% due to U.S. deferredfederal tax assets and foreign withholding and income taxes.

reform.
We recorded a provision for incomeincomes taxes of $15.8$3.4 million for the year ended December 31, 2016,2019, which was primarily comprised of taxes on foreign earnings, the full valuation allowance on U.S. federal deferred tax assets, withholding taxes, other foreign taxestax expense, and current state taxes.acquisition-related impacts. For the year ended December 31, 2016,2019, we paid withholding taxes of $22.0$17.1 million. We recorded a benefit from incomeprovision for incomes taxes of $151.2$87.3 million for the year ended December 31, 2015,2018, which was primarily comprised of tax benefit from the release of thefull valuation allowance on U.S. federal deferred taxes offset by federal state and foreign taxes.tax assets. For the year ended December 31, 2015,2018, we paid withholding taxes of $20.4 million.

We recorded a provision for incomeincomes taxes of $24.0$63.9 million for the year ended December 31, 2014,2017, which was primarily comprised of withholding taxes, otherour valuation allowance on unused 2010 foreign taxestax credits and current state taxes.certain federal research and development credits, and our deferred remeasurements following U.S. federal tax reform. For the year ended December 31, 2014,2017, we paid withholding taxes of $19.4$20.5 million.
WeThe Company periodically evaluateevaluates the realizability of ourits net deferred tax assets based on all available evidence, both positive and negative. The realizability of our net deferred tax assets is dependent on our ability to generate sufficient future taxable income during periods prior to the expiration of tax attributes to fully utilize these assets. During the third quarter of 2015, we2018, the Company assessed the changes in its underlying facts and circumstances and evaluated the realizability of our netits existing deferred tax assets based on all available evidence, both positive and negative, and determined that it was appropriatethe weight accorded to release theeach, and concluded a full valuation allowance for ourassociated with U.S. federal and other stateCalifornia deferred tax assets in accordance with FASB ASC 740-10-30-16was appropriate. As such, the Company has set up and continues to 25.
We emerged frommaintain a cumulative loss position over the previous three years during the first quarter of 2015. The cumulative three-year pre-tax income is considered positive evidence which is objective and verifiable, and thus, received significant weighting. The continued stability in our operations along with the increased visibility into the adoption of our security technology in the third quarter of 2015 provided additional evidence to our belief that we will generate sufficient taxable income in the future. Additional positive evidence considered by us in our assessment included a lack of unused operating loss carryforwards in our history as well as anticipated future benefits from our cost management. Negative evidence we considered included economic uncertainties such as volatility of the semiconductor industry and uncertainties associated with the development of new products that could impact our ability to generate a sustained level of future profits.full valuation allowance against its U.S. federal deferred tax assets.
Liquidity and Capital Resources
December 31,
2016
 December 31, 2015
December 31,
2019
 
December 31,
2018
(In millions)(In millions)
Cash and cash equivalents$135.3
 $143.8
$102.2
 $115.9
Marketable securities36.9
 143.9
305.5
 161.9
Total cash, cash equivalents, and marketable securities$172.2
 $287.7
$407.7
 $277.8
Years Ended December 31,Years Ended December 31,
2016 2015 20142019 2018 2017
(In millions)(In millions)
Net cash provided by operating activities$92.5
 $76.4
 $76.5
$128.5
 $87.1
 $117.4
Net cash provided by (used in) investing activities$(105.2) $1.1
 $(97.9)
Net cash used in investing activities$(141.5) $(68.0) $(75.5)
Net cash provided by (used in) financing activities$5.8
 $(87.8) $(163.0)$(0.3) $(127.7) $46.5
Liquidity
We currently anticipate that existing cash, cash equivalents and marketable securities balances and cash flows from operations will be adequate to meet our cash needs for at least the next 12 months. Additionally, the majority of our cash and cash equivalents areis in the United States. Our cash needs for the year ended December 31, 20162019 were funded primarily from cash collected from our customers.

We do not anticipate any liquidity constraints as a result of either the current credit environment or investment fair value fluctuations. Additionally, we have the intent and ability to hold our debt investments that have unrealized losses in accumulated other comprehensive gain (loss) for a sufficient period of time to allow for recovery of the principal amounts invested. Additionally,Further, we have no significant exposure to European sovereign debt. We continually monitor the credit risk in our portfolio and mitigate our credit risk exposures in accordance with our policies.

As a part of our overall business strategy, from time to time, we evaluate businesses and technologies for potential acquisitionacquisitions that are aligned with our core business and designed to supplement our growth, including the acquisitions of SCS, the assets of the Snowbush IP group and the Memory Interconnect Business.

growth.
To provide us with more flexibility in returning capital back to our shareholders,stockholders, on January 21, 2015, our Board authorized a share repurchase program authorizing the repurchase of up to an aggregate of 20.0 million shares. In the fourth quarter of 2015,During 2019, we entered into an accelerated sharedid not repurchase program to repurchase an aggregate of $100.0 million of our common stock and received an initial delivery of 7.8 million shares. During the second quarter of 2016, the accelerated share repurchase

program was completed and we received an additional 0.7 millionany shares of our common stock as the final settlement of the acceleratedunder our share repurchase program. We may continue to tactically execute the share repurchase program from time to time.


As of December 31, 2016,2019, there remained an outstanding authorization to repurchase approximately 11.53.6 million shares of our outstanding common stock under the current share repurchase program. SeeRefer to “Share Repurchase Program” below.

37



Operating Activities
Cash provided by operating activities of $92.5$128.5 million for the year ended December 31, 20162019 was primarily attributable to the cash generated from customer licensing billings, technology and software licenselicenses and related implementation, support and maintenance fees, product sales, and engineering services fees. Changes in operating assets and liabilities for the year ended December 31, 20162019 primarily included a decreasedecreases in accounts receivable, unbilled receivables and deferred revenue, offset by increases in prepaids and other current assets, inventories and accrued salaries and benefits and other liabilities mainly due to the payout of the Corporate Incentive Plan and increases in deferred revenue and inventory.benefits.

Cash provided by operating activities of $76.4$87.1 million for the year ended December 31, 20152018 was primarily attributable to the cash generated from customer licensing. Additionally, there was a non-cash deferred tax adjustment to reconcile net income to net cash provided by operating activities due to the release of the valuation allowance on our U.S. deferred tax assets of approximately $174.5 million during the third quarter of 2015.licensing billings, technology and software licenses and related implementation, support and maintenance fees, product sales and engineering services fees. Changes in operating assets and liabilities for the year ended December 31, 20152018 primarily included an increaseincreases in unbilled receivables, accounts receivable arising from a renewal of a license agreement with a technology licensing customer in the fourth quarter of 2015, an increase inand prepaids and other current assets, offset by decreases in accounts payable and decrease in accrued salaries and benefits and other liabilities.


Cash provided by operating activities of $76.5$117.4 million for the year ended December 31, 20142017 was primarily attributable to the cash generated from customer licensing.licensing billings, technology and software licenses and related implementation, support and maintenance fees, product sales and engineering services fees. Changes in operating assets and liabilities for the year ended December 31, 20142017 primarily included a decreaseincreases in accounts receivable and accrued salaries and benefits and other accrued liabilities primarily due to the payment of retention bonusesas well as decreases in prepaids and an increase in accounts receivable, offset by increases in income taxes payable and deferred revenue.other current assets.

38



Investing Activities
Cash used in investing activities of $105.2$141.5 million for the year ended December 31, 20162019 primarily consisted of cashpurchases of available-for-sale marketable securities of $657.4 million, $21.9 million paid for the acquisition of SCS of $92.6 million,Northwest Logic, net of cash acquired of $12.1$0.1 million, cash$45.0 million paid for the acquisition of the Memory Interconnect BusinessSecure Silicon IP and Protocols business from Verimatrix, formerly Inside Secure, and $6.5 million paid to acquire property, plant and equipment, offset by proceeds from the maturities and sale of $90.0available-for-sale marketable securities of $507.4 million cashand $6.8 million, respectively, and net proceeds of $76.0 million from the divestiture of the Company’s Payments and Ticketing businesses.
Cash used in investing activities of $68.0 million for the year ended December 31, 2018 primarily consisted of purchases of available-for-sale marketable securities of $282.1 million, $10.8 million paid to acquire property, plant and equipment and $3.0 million paid for investment in a privately held company, offset by proceeds from the acquisitionmaturities of available-for-sale marketable securities of $223.1 million, proceeds from the sale of assets held for sale of $3.8 million and proceeds from the Snowbush IP group assetssale of $32.0an equity security of $1.3 million.

Cash used in investing activities of $75.5 million for the year ended December 31, 2017 primarily consisted of cash paid for purchases of available-for-sale marketable securities of $54.9$102.5 million $8.6and $9.4 million paid to acquire property, plant and equipment, offset by proceeds from the maturities and sales of available-for-sale marketable securities of $110.1$32.0 million and $50.5$4.5 million, respectively.
Financing Activities
Cash provided by investingused in financing activities of $1.1was $0.3 million for the year ended December 31, 20152019 and was primarily consisteddue to $8.4 million in payments under installment payment arrangements to acquire fixed assets and $7.0 million in payments of taxes on restricted stock units, offset by $15.1 million proceeds from the maturities and salesissuance of available-for-sale marketable securities of $112.7 million and $48.4 million, respectively. This was partially offset by cash paid for purchases of available-for-sale marketable securities of $157.8 million and $6.1 million paid to acquire property, plant and equipment. In addition, we received $3.9 million from the sale of intellectual property and the sale of property, plant and equipment.

common stock under equity incentive plans.
Cash used in investingfinancing activities of $97.9was $127.7 million for the year ended December 31, 20142018 and was primarily consisteddue to the repayment of cash paid for purchasesthe remaining aggregate principal of available-for-sale marketable securitiesthe 2018 Notes amounting to $81.2 million, which became due in August 2018, an aggregate payment of $240.3$50.0 million to Citibank N.A., as part of our accelerated share repurchase program, and $6.8 million in payments of taxes on restricted stock units, offset by $11.4 million proceeds from the maturities and salesissuance of available-for-sale marketable securities of $118.7 million and $25.0 million, respectively. In addition, we paid $7.2 million to acquire property, plant and equipment. We also received $5.9 million from the sale of intellectual property.common stock under equity incentive plans.
Financing Activities
Cash provided by financing activities was $5.8$46.5 million for the year ended December 31, 2016. We received2017 and was primarily due to $172.5 million from the issuance of the 2023 Notes, $23.2 million from the issuance of warrants and $15.8 million proceeds of $15.4 million from the issuance of common stock under equity incentive plans, offset by $72.3 million paid for the paymentrepurchase of $56.8 million aggregate principal amount of the additional purchase consideration from the SCS acquisition of $10.22018 Notes and $15.5 million and $0.6 million in principal payments made against the lease financing obligation.
Cash used in financing activities was $87.8 millionpaid primarily for the year ended December 31, 2015 and was primarily due toconversion feature of the repurchased 2018 Notes, an aggregate payment of $100.0$50.0 million to Citibank, N.A.,Barclays Bank PLC, as part of our accelerated share repurchase program. We also paid $0.1 million in fees related to the accelerated share repurchase program. We received proceeds of $13.8 million from the issuance of common stock under equity incentive plans, paid $1.7 million due to payments under installment payment arrangements to acquire fixed assets and paid $0.5program, $33.5 million related to the principal payments against the lease financing obligation.

Cash used in financing activities was $163.0 million for the year ended December 31, 2014. We repaid the principalpurchase of the 2014 convertible senior notes amountingConvertible Note Hedge Transactions, $5.1 million in payments of taxes on restricted stock units and $3.3 million in issuance costs related to $172.5 million, which became due in June 2014. We also received proceeds of

$11.1 million from the issuance of common stock under equity incentive plans, paid $1.8 million due to payments under installment payment arrangements to acquire fixed assets and paid $0.3 million related to the principal payments against the lease financing obligation.2023 Notes.
Contractual Obligations
On December 15, 2009, we entered into a lease agreement for approximately 125,000 square feet of office space located at 1050 Enterprise Way in Sunnyvale, California commencing on July 1, 2010 and expiring on June 30, 2020. The office space is used for our corporate headquarters, as well as engineering, sales, marketing and administrative operations and activities. We have two options to extend the lease for a period of 60 months each and a one-time option to terminate the lease after 84 months in exchange for an early termination fee. Pursuant to the terms of the lease, the landlord agreed to reimburse us approximately $9.1$9.1 million,, which was received by the year ended December 31, 2011. We recognized the reimbursement as an additional imputed financing obligation as such payment from the landlord is deemed to be an imputed financing obligation. On November 4, 2011, to better plan for future expansion, we entered into an amended lease for our Sunnyvale facility for approximately an additional 31,000 square feet of space commencing on March 1, 2012 and expiring on June 30, 2020. Additionally, a tenant improvement allowance to be provided by the landlord was approximately $1.7 million. On September 29, 2012, we entered into a second amended Sunnyvale lease to reduce the tenant improvement allowance to approximately $1.5 million.$1.5 million. On January 31, 2013, we entered into a third amendment to the Sunnyvale lease to surrender the 31,000 square-foot space from the first amendment back to the landlord and recorded a total charge of $2.0 million related to the surrender of the amended lease.
On March 8, 2010, we entered into a lease agreement for approximately 25,000 square feet of office and manufacturing areas, located in Brecksville, Ohio. The office space iswas used for RLD’sour lighting division’s engineering activities while the manufacturing space iswas used for the manufacturer of prototypes. This lease was amended on September 29, 2011to expand the facility to approximately 51,000 total square feet and the amended lease will expireexpired on July 31, 2019. We havehad an option to extend the lease for a period of 60 months. During 2018, we closed our lighting division and manufacturing operations in

Brecksville, Ohio, and sold the related equipment. Refer to Note 18, “Restructuring Charges,” of Notes to Consolidated Financial Statements of this Form 10-K for additional details.
We undertook a series of structural improvements to ready the Sunnyvale and Brecksville facilities for our use. Since certain improvements to be constructed by us were considered structural in nature and we were responsible for any cost overruns, for accounting purposes, we were treated in substance as the owner of the construction project during the construction period. At the completion of each construction, we concluded that we retained sufficient continuing involvement to preclude de-recognition of the building under the FASB authoritative guidance applicable to the sale leasebacks of real estate. As such, prior to January 1, 2019 when the New Leasing Standard became effective for us, we continue to accountaccounted for the buildingbuildings as owned real estate and to recordrecorded an imputed financing obligation for our obligationobligations to the legal owners. Upon adoption of the New Leasing Standard, these leases were treated as operating leases.
MonthlyPrior to the adoption of the New Leasing Standard, monthly lease payments on the facility arewere allocated between the land element of the lease (which iswas accounted for as an operating lease) and the imputed financing obligation. The imputed financing obligation iswas amortized using the effective interest method and the interest rate was determined in accordance with the requirements of sale leaseback accounting. For the years ended December 31, 2016, 20152018 and 2014,2017, we recognized in our Consolidated Statements of Operations $4.4$4.3 million, $4.5 and $4.4 million, and $4.5 million, respectively, of interest expense in connection with the imputed financing obligation on these facilities. At December 31, 2016 and 2015,2018, the imputed financing obligation balance in connection with these facilities was $38.9$37.6 million, and $39.3 million, respectively, which was primarily classified under long-term imputed financing obligation.
On June 29, 2009,July 8, 2019, we entered into a definitive triple net space lease agreement with 237 North First Street Holdings, LLC (the “Landlord”), whereby we will lease approximately 90,000 square feet of office space located at 4453 North First Street in San Jose, California (the “Lease”). The office space will serve as our corporate headquarters and include engineering, marketing and administrative functions. We expect to move to the new premises during the summer of 2020. The Lease has a term of 128 months from the commencement date in October 2019. The starting rent of the Lease is approximately $3.26 per square foot on a triple net basis. The annual base rent increases each year to certain fixed amounts over the course of the term as set forth in the Lease and will be $4.38 per square foot in the eleventh year. In addition to the base rent, we will also pay operating expenses, insurance expenses, real estate taxes, and a management fee. The Lease also allows for an option to expand, wherein we have the right of first refusal to rent additional space in the building. We have a one-time option to extend the Lease for a period of 60 months and may elect to terminate the Lease, via written notice to the Landlord, in the event the office space is damaged or destroyed. Total future required payments under the Lease are approximately $41.0 million.
On November 17, 2017, we entered into an Indenture with U.S. Bank, National Association, as trustee, relating to the issuance by us of $150.0$172.5 million aggregate principal amount of the 2014 Notes. On July 10, 2009, an additional $22.5 million in aggregate principal amount of 2014 Notes were issued as a result of the underwriters exercising their overallotment option. During the second quarter of 2014, we paid upon maturity the entire $172.5 million in aggregate principal amount of the 2014 Notes. See Note 10, “Convertible Notes,” of Notes to Consolidated Financial Statements of this Form 10-K for additional details.
On August 16, 2013, we entered into an Indenture with U.S. Bank, National Association, as trustee, relating to the issuance by us of $138.0 million aggregate principal amount of the 20182023 Notes. The aggregate principal amount of the 20182023 Notes as of December 31, 2016 and 20152019 was $138.0$172.5 million, offset by unamortized debt discount of and unamortized debt issuance costs of $10.9 million and $0.9 million, respectively, and $17.1$22.2 million and $1.5 million, respectively, on the accompanying consolidated balance sheets. The unamortized discount related to the 20182023 Notes is being amortized to interest expense using the effective interest method over the remaining 20 months3.1 years until maturity of the 20182023 Notes on August 15, 2018. SeeFebruary 1, 2023. Refer to Note 10,12, “Convertible Notes,” of Notes to Consolidated Financial Statements of this Form 10-K for additional details.

As of December 31, 20162019, our material contractual obligations are as follows (in thousands):
Total 2017 2018 2019 2020 2021 ThereafterTotal 2020 2021 2022 2023 2024
Contractual obligations (1)             
Imputed financing obligation (2)$22,220
 $6,302
 $6,447
 $6,602
 $2,869
 $
 $
Leases and other contractual obligations10,837
 5,649
 2,606
 1,432
 603
 543
 4
Contractual obligations (1) (2)           
Other contractual obligations$468
 $234
 $234
 $
 $
 $
Software licenses (3)24,255
 10,497
 10,226
 3,532
 
 
 
31,530
 13,525
 11,977
 6,028
 
 
Acquisition retention bonuses (4)9,998
 3,499
 3,499
 3,000
 
 
Convertible notes138,000
 
 138,000
 
 
 
 
172,500
 
 
 
 172,500
 
Interest payments related to convertible notes3,105
 1,553
 1,552
 
 
 
 
8,308
 2,372
 2,372
 2,372
 1,192
 
Total$198,417
 $24,001
 $158,831
 $11,566
 $3,472
 $543
 $4
$222,804
 $19,630
 $18,082
 $11,400
 $173,692
 $

(1)
The above table does not reflect possible payments in connection with uncertainunrecognized tax benefits of approximately $21.924.6 million including $19.7$22.8 million recorded as a reduction of long-term deferred tax assets and $2.2$1.8 million in long-term income taxes payable, as of December 31, 20162019. As noted in Note 16,19, “Income Taxes,” of Notes to Consolidated Financial Statements of this Form 10-K, although it is possible that some of the unrecognized tax benefits could be settled within the next 12 months, we cannot reasonably estimate the outcome at this time.

(2)With respectFor our lease commitments as of December 31, 2019, refer to the imputed financing obligation, the main componentsNote 10, “Leases,” of the difference between the amount reflected in the contractual obligations table and the amount reflected on theNotes to Consolidated Balance Sheets are the interest on the imputed financing obligation and the estimated common area expenses over the future periods. The amount includes the amended Ohio lease and the amended Sunnyvale lease.Financial Statements of this Form 10-K.
(3)
We have commitments with various software vendors for non-cancellable agreements generally having terms longer than one year.
(4)In connection with the acquisitions of Northwest Logic in August 2019 and the Secure Silicon IP and Protocols business in December 2019, we are obligated to pay retention bonuses to certain employees subject to certain eligibility and acceleration provisions including the condition of employment.
Share Repurchase Program
During the year ended December 31, 2016,2019, we repurchased and retired 0.7 milliondid not repurchase any shares of our common stock under our share repurchase program.

On January 21, 2015, our Board approved a share repurchase program authorizing the repurchase of up to an aggregate of 20.0 million shares. Share repurchases under the plan may be made through the open market, established plans or privately negotiated transactions in accordance with all applicable securities laws, rules, and regulations. There is no expiration date applicable to the plan. 

On October 26, 2015,March 5, 2018, we initiated an accelerated share repurchase program with Citibank N.A. The accelerated share repurchase program is part of the broader share repurchase program previously authorized by the Company’s Board on January 21, 2015. Under the accelerated share repurchase program, we pre-paid to Citibank N.A., the $50.0 million purchase price for our common stock and, in turn, we received an initial delivery of approximately 3.1 million shares of our common stock from Citibank N.A., in the first quarter of 2018, which were retired and recorded as a $40.0 million reduction to stockholders’ equity. The remaining $10.0 million of the initial payment was recorded as a reduction to stockholders’ equity as an unsettled forward contract indexed to our stock. During the second quarter of 2018, the accelerated share repurchase program was completed and we received an additional 0.7 million shares of our common stock as the final settlement of the accelerated share repurchase program. There were no other repurchases of our common stock during 2018.

On May 1, 2017, we initiated an accelerated share repurchase program with Barclays Bank PLC. The accelerated share repurchase program is part of the broader share repurchase program previously authorized by our Board on January 21, 2015. Under the accelerated share repurchase program, we pre-paid to Citibank, N.A.,Barclays Bank PLC, the $100.0$50.0 million purchase price for our common stock and, in turn, we received an initial delivery of approximately 7.83.2 million shares of our common stock from Citibank, N.A,Barclays Bank PLC, in the fourthsecond quarter of 2015,2017, which were retired and recorded as a $80.0$40.0 million reduction to stockholders'stockholders’ equity. The remaining $20.0$10.0 million of the initial payment was recorded as a reduction to stockholders’ equity as an unsettled forward contract indexed to our stock. The number of shares to be ultimately purchased by us was determined based on the volume weighted average price of the common stock during the terms of the transaction, minus an agreed upon discount between the parties. During the secondfourth quarter of 2016,2017, the accelerated share repurchase program was completed and we received an additional 0.70.8 million shares of our common stock as the final settlement of the accelerated share repurchase program. There were no other repurchases of our common stock during 2017.


As of December 31, 2016,2019, there remained an outstanding authorization to repurchase approximately 11.53.6 million shares of our outstanding common stock under the current share repurchase program.


We record stock repurchases as a reduction to stockholders’ equity. We record a portion of the purchase price of the repurchased shares as an increase to accumulated deficit when the price of the shares repurchased exceeds the average original proceeds per share received from the issuance of common stock.
Warrants

In connection with the 2023 Notes, we separately entered into privately negotiated warrant transactions, whereby we sold to the Counterparties warrants (the “Warrants”) to acquire, collectively, subject to anti-dilution adjustments, approximately 9.1 million shares of our common stock at an initial strike price of approximately $23.30 per share, which represents a premium of 60% over the last reported sale price of our common stock of $14.56 on November 14, 2017. We received aggregate proceeds of approximately $23.2 million from the sale of the Warrants to the Counterparties. The Warrants are separate transactions and are not part of the 2023 Notes or Convertible Note Hedge Transactions. Holders of the 2023 Notes and Convertible Note Hedge Transactions will not have any rights with respect to the Warrants. Refer to Note 12, “Convertible Notes,” of Notes to Consolidated Financial Statements of this Form 10-K for additional details.


Critical Accounting Policies and Estimates
The discussion and analysis of our financial condition and results of operations are based upon our consolidated financial statements, which have been prepared in accordance with accounting principles generally accepted in the United States. The preparation of these financial statements requires us to make estimates and judgments that affect the reported amounts of assets, liabilities, revenue and expenses, and related disclosure of contingent assets and liabilities. On an ongoing basis, we evaluate our estimates, including those related to revenue recognition, investments, income taxes, litigation and other contingencies. We base our estimates on historical experience and on various other assumptions that are believed to be reasonable under the circumstances, the results of which form the basis for making judgments about the carrying values of assets and liabilities that are not readily apparent from other sources. Actual results may differ from these estimates under different assumptions or conditions.
We believe the following critical accounting policies affect our more significant judgments and estimates used in the preparation of our consolidated financial statements.
Revenue Recognition
Overview
We adopted the New Revenue Standard on January 1, 2018 and all the related amendments using the modified retrospective method. We recognized the cumulative effect of initially applying the new revenue standard as an adjustment to the opening balance of accumulated deficit as of January 1, 2018. The comparative information for 2017 has not been recast and continues to be reported under the accounting standards in effect for that period.
We recognize revenue when persuasive evidenceupon transfer of control of promised goods and services in an amount that reflects the consideration we expect to receive in exchange for those goods and services. Unless indicated otherwise below, all of the goods and services are distinct and are accounted for as separate performance obligations.
Where an arrangement exists, weincludes multiple performance obligations, the transaction price is allocated to these on a relative standalone selling prices basis. We have delivered the productestablished standalone selling prices for all of our offerings - specifically, a same pricing methodology is consistently applied to all licensing arrangements; all services offerings are priced within tightly controlled bands and all contracts that include support and maintenance state a renewal rate or performed the service, the fee is fixed or determinable and collection is reasonably assured. If any of these criteria are not met, we defer recognizing the revenue until such time as all criteria are met. Determination of whether or not these criteria have been met may require us to make judgments, assumptions and estimates based upon current information and historical experience.
For arrangements that involve the delivery of more than one element, each license, service or product is evaluated to determine whether it qualifies as a separate unit of accounting. This determination is based on whether the deliverable has “stand-alone value” to the customer. The considerationprice that is fixed or determinable is then allocated to each separate unit of accounting based on the relative selling price of each deliverable. We determine the relative selling price for a deliverable based on its best estimate of selling price (“BESP”). Except for some revenue associated to the acquisition of Bell Identification Ltd., we have determined that vendor-specific objective evidence of selling price for each deliverable is not available as it lacks a consistent number of standalone sales and third-party evidence is not a practical alternative due to differences in its service offerings compared to other parties and the availability of relevant third-party pricing information. We determined BESP by considering our overall pricing objectives and market conditions. Significant pricing practices taken into consideration include discounting practices, the size and volume of transactions, the customer demographic, the geographic area where services are sold, price lists, go-to-market strategy, historical standalone sales and contract prices. The determination of BESP is made through consultation with and approval by our management, taking into consideration the go-to-market strategy. As the go-to-market strategies evolve, we may modify our pricing practices in the future, which could result in changes in relative selling prices. In most cases, the relative values of the undelivered components are not material to the overall arrangement and are typically delivered within twelve months after the core product has been delivered. In such agreements, selling price is determined for each component and any difference between the total of the separate BESP and total contract consideration (i.e. discount) is allocated pro-rata across each of the components in the arrangement.
During the first quarter of 2016, we acquired Smart Card Software Ltd., which included Bell Identification Ltd. and Ecebs Ltd., which transact mostly in software and hosted services (SaaS) arrangements, respectively. For software arrangements that include multiple elements, including software licenses, professional services and maintenance services, we allocate and defer revenue for the undelivered items (typically only the maintenance services) based on the fair value using vendor specific objective evidence (“VSOE”), and recognize the difference between the total arrangement fee and the amount deferred for the undelivered item(s) as revenue. VSOE of fair value of each maintenance element is based on the contractual stated renewal rate for that maintenance element. When VSOE of fair value does not exist for undelivered items, the entire arrangement fee is recognized ratably over the performance period. For hosted services arrangements, we recognize the arrangements over the service obligation period.systematically enforced.
Our revenue consists of royalty, revenueproduct and contract and other revenue derived from MID, RSD and RLD operating segments.revenue. Royalty revenue consists of patent license and technology license royalties. Products consist of memory interface chips sold directly and indirectly to module manufacturers and OEMs worldwide through multiple channels, including our direct sales force and distributors. Contract and other revenue consists of software license fees, engineering fees associated with integration of our technology solutions into our customers' relatedcustomers’ products and support and maintenance as well as sale of products.
During 2013, we expanded our business strategy of monetizing our patent portfolio to include the sale of selected intellectual property. Our MID business continues to grow its patent portfolio and actively engages with various external parties to monetize the patent portfolio and explore new revenue opportunities. As the sales of such patents developed by our MID business unit under this expanded strategy represents a component of our ongoing major or central operations, we record the


related proceeds as revenue. We will recognize the revenue when there is persuasive evidence of a sales arrangement, fees are fixed or determinable, delivery has occurred and collectibility is reasonably assured. These requirements are generally fulfilled upon closing of the patent sale transaction.
fees.
Royalty Revenue
WeOur patent and technology licensing arrangements generally recognize royalty revenue upon notification by our customersrange between 1 and when deemed collectible. The terms of7 years in duration and generally grant the royalty agreements generally either require customers to give us notification and to pay the royalties within a specified period or are based on a fixed royalty that is due within a specified period. Many of our customers havelicensee the right to cancel their licenses. Inuse our entire IP portfolio as it evolves over time. These arrangements do not typically grant the licensee the right to terminate for convenience and where such arrangements, revenuerights exist, termination is only recognized to the extent that is consistent with the cancellation provisions. Cancellation provisions within such contracts generally provide for a prospective, cancellation with no refund of fees already remittedpaid by customers for products providedthe licensee. There is no interdependency or interrelation between the IP included in the portfolio licensed upon contract inception and payment for services rendered priorany IP subsequently made available to the datelicensee, and we would be able to fulfill our promises by transferring the portfolio and the additional IP use rights independently. However, the numbers of cancellation. We have two types of royalty revenue: (1)additions to, and removals from the portfolio (for example when a patent license royaltiesexpires and (2) technology license royalties.
Patent licenses - We license our broad portfolio of patented inventionsrenewal is not granted to companies who use these inventions in the development and manufacture of their own products. Such licensing agreements may cover the license of part, or all, of our patent portfolio. The contractual terms of the agreements generally provide for payments over an extended period of time. For the licensing agreements with fixed royalty payments, we generally recognize revenue from these arrangements as amounts become due. For the licensing agreements with variable royalty payments which can be based on either a percentage of sales or number of units sold, we earn royalties at the time that the customers’ sales occur. Our customers, however, do not report and pay royalties owed for salesus) in any given quarter until afterperiod have historically been relatively consistent; as such, we do not allocate the conclusiontransaction price between the rights granted at contract inception and those subsequently granted over time as a function of that quarter. As we are unable to estimate the customers’ salesthese additions.
Patent and technology licensing arrangements result in any given quarter to determine the royalties due to us, we recognize royalty revenues basedfixed payments received over time, with guaranteed minimum payments on royalties reported by customers during the quarter and when other revenue recognition criteria are met.
In addition, we may enter into certain settlements of patent infringement disputes. The amount of consideration received upon any settlement (including but not limited to past royaltyoccasion, variable payments future royalty payments and punitive damages) is allocated to each element of the settlementcalculated based on the fair value of each element. In addition, revenues related to past royalties are recognized upon executionlicensee’s sale or use of the agreement by both parties, providedIP, or a mix of fixed and variable payments.
For fixed-fee arrangements (including arrangements that the amountsinclude minimum guaranteed amounts), variable royalty arrangements that we have concluded are fixed or determinable, there are noin substance and the fixed portion of hybrid fixed/variable arrangements, we recognize revenue upon control over the underlying IP use right transferring to the licensee, net of the effect of significant undeliveredfinancing components calculated using customer-specific, risk-adjusted lending rates ranging between 3% and 6%, with the related interest income being recognized over time on an effective rate basis. Where a licensee has the contractual right to terminate a fixed-fee arrangement for convenience without any substantive penalty


payable upon such termination, we apply the guidance in the New Revenue Standard to the duration of the contract in which the parties have present enforceable rights and obligations and collectability is reasonably assured. We do notonly recognizes revenue for amounts that are due and payable.
For variable arrangements, we recognize any revenues prior to executionrevenue based on an estimate of the agreement since there is no reliable basis on which we can estimatelicensee’s sale or usage of the amounts for royalties related to previous periods or assess collectability. Elements that are related to royalty revenue in nature (including but not limited to past royalty payments and future royalty payments) will be recorded as royalty revenue in the consolidated statements of operations. Elements that are not related to royalty revenue in nature (including but not limited to punitive damage and settlement) will be recorded as gain from settlement which is reflected as a separate line item within the operating expenses section in the consolidated statements of operations.
Technology licenses - We develop proprietary and industry-standard products that we provide to our customers under technology license agreements. These arrangements include royalties, which can be based on either a percentage of sales or number of units sold. We earn royalties on such licensed products sold worldwide by our customers at the time that the customers’ sales occur. Our customers, however, do not report and pay royalties owed for sales in any given quarter until after the conclusion of that quarter. As we are unable to estimate the customers’ sales in any given quarter to determine the royalties due to us, we recognize royalty revenues based on royalties reported by customersIP during the quarter andperiod of reference, typically quarterly, with a true-up being recorded when other revenue recognition criteria are met.
Contract and Other Revenue
We recognize revenuewe receive the actual royalty report from the sale of productslicensee.

Product Revenue
Product revenue is recognized upon shipment of the product to our customers, net of accruals for estimated sales returns and allowances, whichand to date, have not been significant. However, somedistributors, net of our sales are made through distributors under arrangements that allowaccruals for price protection orand rights of return on productproducts unsold by the distributors. Product revenue on sales made through distributorsTo date, none of these accruals have been significant. We transact with rights of return or price protection is deferred until the distributors sell the product to end customers. Sales to distributors are included in deferred revenue and we defer the related costs until sale to the end customers occurs. Price protection rights allow distributors the right to a credit in the event of declines in the price of our product that they hold prior to the sale to an end customer. In the event that we reduce the selling price of products held by distributors, deferred revenue related to distributors with price protection rights is reduced upon notification to the customer of the price change. Our sales to direct customers are made primarily pursuant to standard purchase orders for delivery of products. Weproducts and generally allow customers to cancel or change purchase orders within limited notice periods prior to the scheduled shipment.shipment date.
ForContract and Other Revenue
Contract and other revenue consists of software arrangements that include multiple elements, includinglicense fees and engineering fees associated with integration of our technology solutions into our customers’ solutions (or products) and related support and maintenance.
An initial software licenses, professionalarrangement generally consists of a term-based or perpetual license, significant software customization services and support and maintenance services we allocate and defer revenue for the undelivered items (typically only the maintenance services) based on the fair value using vendor specific objective evidence (“VSOE”), and recognize the difference between the total


arrangement fee and the amount deferred for the undelivered item(s) as revenue. VSOE of fair value of each maintenance element is based on the contractual stated renewal rate for that maintenance element. When VSOE of fair value does not exist for undelivered items, the entire arrangement fee is recognized ratably over the performance period.
For software arrangements, we use the percentage-of-completion method for contracts that involve the implementation of software solutions and that qualify for percentage-of-completion revenue accounting (e.g. software arrangements that contain a PCS element that has VSOE of fair value established and that have no refund rights that would allow a customer refunds of fees paid under the arrangement). Revenue is recognized based on man-days incurred during the reporting period as compared to the estimated total man-days necessary for each contract, not to exceed the billable project acceptances received, with deferral of corresponding contract costs, if applicable. Should a loss be anticipated on a contract, the full amount of the loss would be recorded when the loss is determinable. Maintenance and support revenue includesinclude post-implementation customer support and the right to unspecified software updates and enhancements on a when and if available basis. We recognize license and customization services revenue based on an over time model, measured using the input method. Due to the nature of the work performed in these arrangements, the estimation of the over time model is complex and involves significant judgment. The key factor reviewed by us to estimate costs to complete each contract is the estimated man-months necessary to complete the project. We recognize license renewal revenue at the beginning of the renewal period. We recognize revenue from professional services purchased in addition to an initial software arrangement on a cumulative catch-up basis if these services are not distinct from the services provided as part of the initial software arrangement, or as a separate contract if these services are distinct.
Prior to the divestiture of our Payments and Ticketing businesses in 2019, our Payment Product Group derived a significant portion of its revenue from heavily customized software in the mobile market, whereby the Payment Product Group’s software solution interacts with third-party solutions and other payment platforms to provide the functionality the customer requires. Historically, these third-party solutions have evolved at a rapid pace, with the Payment Product Group being required to deliver as part of its support and maintenance services the patches and updates needed to maintain the functionality of its own software offering. As the utility of the solution to the end customer erodes very quickly without these updates, these were viewed as critical and the customized software solution and updates were not separately identifiable. As such, these arrangements were treated as a single performance obligation; revenue was deferred until completion of the customization services, and recognized ratably over the committed support and maintenance term.
Prior to the divestiture of our Payments and Ticketing businesses in 2019, our Ticketing Products Group primarily derived revenue from ticketing services arrangements that systematically consist of a software component, support and maintenance, managed services and hosting services. The software could be hosted by third-party hosting service providers or us. All arrangements entered into subsequent to the acquisition (we had originally acquired our Payments and Ticketing businesses in 2016) precluded customers from taking possession of the software at any time during the hosting term and we had concluded that should a customer that was under contract as of the acquisition date ever request possession of the software, the Ticketing Products Group would have the ability to charge the customer, and enforce a claim to payment of a substantive fee in exchange for such right, and that the costs of setting up the environment needed to run the software would act as a significant disincentive to the customer taking possession of the software. Based on the above, we concluded that these services were a single performance obligation, with customers simultaneously receiving and consuming the benefits provided by the Ticketing Products Group’s performance, and recognized ticketing services revenue ratably over the term, commencing upon completion of setup activities. We recognized setup fees upon completion. While these activities did not transfer a service to the customer, we elected not to defer and amortized these fees over the expected duration of the customer relationship owing to the immateriality of the amounts charged.
Significant Judgments
Historically and with the exceptions noted below, no significant judgment has generally been required in determining the amount and timing of revenue from our contracts with customers.


For our contract and other revenue, revenue is recognized as services are performed on a percentage-of-completion basis, measured using the input method. Due to the nature of the work performed in these arrangements, the estimation of percentage-of-completion is complex and involves significant judgment. The key factor reviewed by us to estimate costs to complete each contract is the estimated man-months necessary to complete the project. If circumstances arise that change the original estimates of extent of progress toward completion, revisions to the estimates are made that may result in increases or decreases in estimated revenues or costs. Revisions are reflected in revenue on a cumulative catch-up basis in the period in which the circumstances that gave rise to the revision become known. We have adequate tools and controls in place, and substantial experience and expertise in timely and accurately tracking man-months incurred in completing customization and other professional services, are provided.and quantifying changes in estimates.


For development contracts relatedKey estimates used in recognizing revenue predominantly consist of the following:
All fixed-fee arrangements result in cash being received after control over the underlying IP use right has transferred to licensesthe licensee, and over a period exceeding a year. As such, all these arrangements include a significant financing component. We calculate a customer-specific lending rate using a Daily Treasury Yield Curve Rate that changes depending on the date on which the licensing arrangement was entered into and the term (in years) of our solutions that involve significant engineeringthe arrangement, and integration services, we use the proportional performance method. The measurement of progress to completion istake into consideration a licensee-specific risk profile determined based on actual man-months incurred duringa review of the licensee’s “Full Company View” Dun & Bradstreet report obtained on the date the licensing arrangement was signed by the parties, with a risk premium being added to the Daily Treasury Yield Curve Rate considering the overall business risk, financing strength and risk indicators, as listed.

We recognize revenue on variable fee licensing arrangements on the basis of estimates. In connection with the adoption of the New Revenue Standard, we have set up specific procedures and controls to ensure timely and accurate quantification of variable royalties, and implemented new systems to enable the preparation of the estimates and reporting period, not to exceedof the billable project acceptances received. Contract costs are recognized as incurred. Maintenance and support revenue includes minimal hours of post-implementation customer support that is recognized ratably overfinancial information required by the support period.New Revenue Standard.



Goodwill
Goodwill represents the excess of the purchase price over the fair value of the net tangible and identifiable intangible assets acquired in each business combination. Goodwill is not subject to amortization, but is subject to at least an annual assessment for impairment, applying a fair-value based test. We perform our impairment analysis of goodwill on an annual basis during the fourth quarter of the year unless conditions arise that warrant a more frequent evaluation.
GoodwillWhen goodwill is allocatedassessed for impairment, we have the option to perform an assessment of qualitative factors of impairment (optional assessment) prior to necessitating a quantitative impairment test. Should the variousoptional assessment be used for any given year, qualitative factors to consider for a reporting units which are generally operating segments. The goodwill impairmentunit include: cost factors; financial performance; legal, regulatory, contractual, political, business, or other factors; entity specific factors; industry and market considerations; macroeconomic conditions; and other relevant events and factors affecting the reporting unit. If we determine in the qualitative assessment that it is more likely than not that the fair value of the reporting unit is less than its carrying value, a quantitative test involvesis then performed. Otherwise, no further testing is required. For a two-step process. In the first step,reporting unit tested using a quantitative approach, we compare the fair value of eachthe reporting unit to itswith the carrying value. The fair valuesamount of the reporting units areunit, including goodwill. The fair value of the reporting unit is estimated using an income or discounted cash flows approach.
Under the income approach, we measure fair value of the reporting unit based on a projected cash flow method using a discount rate determined by our management which is commensurate with the risk inherent in ourits current business model. Our discounted cash flow projections are based on ourits annual financial forecasts developed internally by management for use in managing our business. If the fair value of the reporting unit exceeds its carrying value, goodwill is not impaired and no further testing is required. If the fair value of the reporting unit is less than the carrying value, we must perform the second step of the impairment test to measurethen the amount of goodwill impairment loss. Inwill be the second step,amount by which the reporting unit'sunit’s carrying value exceeds its fair value, is allocatednot to all of the assets and liabilities of the reporting unit, including any unrecognized intangible assets, in a hypothetical analysis that calculates the implied fair value of goodwill in the same manner as if the reporting unit was being acquired by a market participant in a business combination. If the implied fair value of the reporting unit's goodwill is less thanexceed the carrying value, the difference is recorded as an impairment loss.
Asamount of December 31, 2016, the fair value of the MID reporting unit, with $66.6 million of goodwill, exceeded the carrying value of its net assets by approximately 299% and the fair value of the RSD reporting unit, with $138.2 million of goodwill, exceeded the carrying value of its net assets by approximately 89%. Key assumptions used to determine the fair value of the MID and RSD reporting units at December 31, 2016, were the revenue growth rates for the forecast period and terminal year, terminal growth rates and discount rates. Certain estimates used in the income approach involve information for new product lines with limited financial history and developing revenue models which increase the risk of differences between the projected and actual performance. The discount rate of 12% for MID and 16.5% for RSD is based on the reporting units’ overall risk profile relative to other guideline companies, market adoption of our technology, the reporting units’ respective industry as well as the visibility of future expected cash flows. The terminal growth rate applied to determine fair value for both reporting units was 3%, which was based on historical experience as well as anticipated economic conditions, industry data and long term outlook for the business. These assumptions are inherently uncertain.
Given the current economic environment and the uncertainties regarding the impact on our business, there can be no assurance that the estimates and assumptions made for purposes of our goodwill impairment testing in the fourth quarter of 2016 will prove to be accurate predictions of the future. If our assumptions regarding forecasted revenues or operating margin rates are not achieved, we may be required to record goodwill impairment charges in future periods, whether in connection with the next annual impairment testing or prior to that if any change constitutes a triggering event outside of the period when the annual goodwill impairment test is performed. It is not possible at this time to determine if any such future impairment charge

would result or, if it does, whether such charge would be material. We believe that the assumptions and rates used in our impairment test are reasonable. However, they are judgmental, and variations in any of the assumptions or rates could result in materially different calculations of impairment amounts.goodwill.
Intangible Assets
Intangible assets are comprised of existing technology, customer contracts and contractual relationships, and other definite-lived and indefinite-lived intangible assets. Identifiable intangible assets resulting from the acquisitions of entities accounted for using the purchase method of accounting are estimated by management based on the fair value of assets received. Identifiable definite-lived intangible assets are being amortized over the period of estimated benefit using the straight-line method and estimated useful lives ranging from 1six months to 10ten years.

We amortize definite-lived assets over their estimated useful lives. We evaluate definite-lived and indefinite-lived assets for impairment whenever events or changes in circumstances indicate the carrying value of an asset may not be recoverable. The carrying value is not recoverable if it exceeds the undiscounted cash flows resulting from the use of the asset and its eventual disposition. Our estimates of future cash flows attributable to our assets require significant judgment based on our historical and anticipated results and are subject to many factors. Factors we consider important which could trigger an impairment review include significant negative industry or economic trends, significant loss of clients, and significant changes in the manner of our use of the acquired assets or the strategy for our overall business.
When we determine that the carrying value of the assets may not be recoverable based upon the existence of one or more of the above indicators of impairment, we measure the potential impairment based on a projected discounted cash flow method using a discount rate determined by our management to be commensurate with the risk inherent in our current business model. An impairment loss is recognized only if the carrying amount of the asset is not recoverable and exceeds its fair value. Different assumptions and judgments could materially affect the calculation of the fair value of our assets.
Acquired indefinite-lived intangible assets related to our in-process research and development ("(“IPR&D"&D”) are capitalized and subject to impairment testing until completion or abandonment of the projects. Upon successful completion of each project, we make a separate determination of useful life of the acquired indefinite-lived intangible assets and the related amortization is recorded as an expense over the estimated useful life of the specific projects. Indefinite-lived intangible assets are subject to at least an annual assessment for impairment, applying a fair-value based test. Under the income approach, we measure fair value of the indefinite-lived intangible assets based on a projected cash flow method using a discount rate determined by our management which is commensurate with the risk inherent in our current business model. Our discounted cash flow projections are based on our annual financial forecasts developed internally by our management for use in managing our business. If the fair value of the indefinite-lived intangible assets exceeds its carrying value, the indefinite-lived intangible assets are not impaired and no further testing is required. If the implied fair value of the indefinite-lived intangible assets is less than the carrying value, the difference is recorded as an impairment loss.
Income Taxes
As part of preparing our consolidated financial statements, we are required to calculate the income tax expense or benefit(benefit) which relates to the pretax income or loss for the period. In addition, we are required to assess the realization of the deferred tax asset or liability to be included on the consolidated balance sheet as of the reporting dates.
As of December 31, 2016,2019, our consolidated balance sheet included net deferred tax assets, before valuation allowance, of approximately $180.2$187.7 million, which consists of net operating loss carryovers, tax credit carryovers, amortization, employee stock-based compensation expenses and certain liabilities, partially reduced by deferred tax liabilities associated with the convertible debt instruments.ASC 606 adoption and certain assets. As of December 31, 2016,2019, we have a valuation allowance of $23.5$197.0 million resulting in net deferred tax assetsliabilities of $156.7$9.3 million.
We periodically evaluate the realizability of our net deferred tax assets based on all available evidence, both positive and negative. The realizability of our net deferred tax assets is dependent on our ability to generate sufficient future taxable income during periods prior to the expiration of tax attributes to fully utilize these assets.
We emerged from a cumulative loss position over the previous three years during the first quarter of 2015. The cumulative three-year pre-tax income is considered positive evidence which is objective and verifiable, and thus, received significant weighting. The continued stability in our operations along with the increased visibility into the adoption of our security technology in the third quarter of 2015 provided additional evidence to our belief that we will generate sufficient taxable income in the future. Additional positive evidence considered by us in our assessment included a lack of unused operating loss carryforwards in our history as well as anticipated future benefits from our cost management. Negative evidence we considered included economic uncertainties such as volatility of the semiconductor industry and uncertainties associated with the development of new products that could impact our ability to generate a sustained level of future profits.

We maintain liabilities for uncertain tax positions within our long-term income taxes payable accounts and as a reduction to existing deferred tax assets or other refundable taxes to the extent tax attributes are available to offset such liabilities. These liabilities involve judgment and estimation and are monitored by us based on the best information available including changes in tax regulations, the outcome of relevant court cases and other information.
Tax attributes related to stock option windfall deductions are not to be recognized until they result in a reduction of cash taxes payable. The benefit of these excess tax benefits will be recorded to equity when they reduce cash taxes payable. We will only recognize a tax benefit from stock-based awards in additional paid-in capital if an incremental tax benefit is realized after all other tax attributes currently available have been utilized. In addition, we have elected to account for the indirect effects of stock-based awards on other tax attributes, such as the research tax credits, through the consolidated statement of operations as part of the tax effect of stock-based compensation.
The calculation of our tax liabilities involves uncertainties in the application of complex tax law and regulations in a multitude of jurisdictions. Although ASC 740, Income“Income Taxes, provides further clarification on the accounting for uncertainty in income taxes, significant judgment is required by us. If the ultimate resolution of tax uncertainties is different from what is currently estimated, it could materially affect income tax expense.
Stock-Based Compensation
We maintained stock plans covering a broad range of potential equity grants including stock options, nonvested equity stock and equity stock units and performance based instruments. In addition, we sponsor an Employee Stock Purchase Plan (“ESPP”), whereby eligible employees are entitled to purchase Common Stock semi-annually, by means of limited payroll deductions, at a 15% discount from the fair market value of the Common Stock as of specific dates.
The accounting guidance for share-based payments requires the measurement and recognition of compensation expense in our statement of operations for all share-based payment awards made to our employees, directors and consultants including employee stock options, nonvested equity stock and equity stock units, and employee stock purchase grants. Stock-based compensation expense is measured at grant date, based on the estimated fair value of the award, reduced by an estimate of the annualized rate of expected forfeitures, and is recognized as expense over the employees’ expected requisite service period, generally using the straight-line method. In addition, the accounting guidance for share-based payments requires the benefits of tax deductions in excess of recognized compensation expense to be reported as a financing cash flow, rather than as an operating cash flow as prescribed under previous accounting rules.flow. Our forfeiture rate


represents the historical rate at which our stock-based awards were surrendered prior to vesting. The accounting guidance for share-based payments requires forfeitures to be estimated at the time of grant and revised on a cumulative basis, if necessary, in subsequent periods if actual forfeitures differ from those estimates. SeeRefer to Note 12,14, “Equity Incentive Plans and Stock-Based Compensation,” of Notes to Consolidated Financial Statements of this Form 10-K for more information regarding the valuation of stock-based compensation.
Business Combinations
We account for acquisitions of businesses using the purchase method of accounting, which requires us to recognize separately from goodwill the assets acquired and the liabilities assumed at their acquisition date fair values. While we use our best estimates and assumptions to accurately value assets acquired and liabilities assumed at the acquisition date as well as contingent consideration, where applicable, the estimates are inherently uncertain and subject to refinement. As a result, during the measurement period, which may be up to one year from the acquisition date, we may record adjustments to the assets acquired and liabilities assumed with the corresponding offset to goodwill. Upon the conclusion of the measurement period or final determination of the values of assets acquired or liabilities assumed, whichever comes first, any subsequent adjustments are recorded to our consolidated statements of operations.
Accounting for business combinations requires us to make significant estimates and assumptions, especially at the acquisition date including our estimates for intangible assets, contractual obligations assumed and pre-acquisition contingencies where applicable. Although we believe the assumptions and estimates made in the past have been reasonable and appropriate, they are based in part on historical experience and information obtained from the management of the acquired companies and are inherently uncertain. Significant estimates and assumptions made by us in estimating the fair value of the existing technologies included revenue growth rates, operating expense margins, technology obsolescence rates and discount rates. Unanticipated events and circumstances may occur that may affect the accuracy or validity of such assumptions, estimates or actual results.

Recent Accounting Pronouncements
SeeRefer to Note 3, “Recent Accounting Pronouncements,” of Notes to Consolidated Financial Statements of this Form 10-K for a full description of recent accounting pronouncements including the respective expected dates of adoption.
Item 7A.Quantitative and Qualitative Disclosures About Market Risk
We are exposed to financial market risks, primarily arising from the effect of interest rate fluctuations on our investment portfolio. Interest rate fluctuation may arise from changes in the market’s view of the quality of the security issuer, the overall economic outlook, and the time to maturity of our portfolio. We mitigate this risk by investing only in high quality, highly liquid instruments. Securities with original maturities of one year or less must be rated by two of the three industry standard rating agencies as follows: A1 by Standard & Poor’s, P1 by Moody’s and/or F-1 by Fitch. Securities with original maturities of greater than one year must be rated by two of the following industry standard rating agencies as follows: AA- by Standard & Poor’s, Aa3 by Moody’s and/or AA- by Fitch. By corporate investment policy, we limit the amount of exposure to $15.0 million or 10% of the portfolio, whichever is lower, for any single non-U.S. Government issuer. A single U.S. Agency can represent up to 25% of the portfolio. No more than 20% of the total portfolio may be invested in the securities of an industry sector, with money market fund investments evaluated separately. Our policy requires that at least 10% of the portfolio be in securities with a maturity of 90 days or less. We may make investments in U.S. Treasuries, U.S. Agencies, corporate bonds and municipal bonds and notes with maturities up to 36 months. However, the bias of our investment portfolio is shorter maturities. All investments must be U.S. dollar denominated. Additionally, we have no significant exposure to European sovereign debt.
We invest our cash equivalents and marketable securities in a variety of U.S. dollar financial instruments such as U.S. Treasuries, U.S. Government Agencies, commercial paper and corporate notes. Our policy specifically prohibits trading


securities for the sole purposes of realizing trading profits. However, we may liquidate a portion of our portfolio if we experience unforeseen liquidity requirements. In such a case, if the environment has been one of rising interest rates we may experience a realized loss, similarly, if the environment has been one of declining interest rates we may experience a realized gain. As of December 31, 2016,2019, we had an investment portfolio of fixed income marketable securities of $121.2$363.5 million including cash equivalents. If market interest rates were to increase immediately and uniformly by 1.0% from the levels as of December 31, 2016,2019, the fair value of the portfolio would decline by approximately $0.1$0.5 million. Actual results may differ materially from this sensitivity analysis.


The fair value of our convertible notes is subject to interest rate risk, market risk and other factors due to the convertible feature. The fair value of the convertible notes will generally increase as interest rates fall and decrease as interest rates rise. In addition, the fair value of the convertible notes will generally increase as our common stock price increases and will generally decrease as our common stock price declines in value. The interest and market value changes affect the fair value of our convertible notes but do not impact our financial position, cash flows or results of operations due to the fixed nature of the debt obligation.
We invoice the majority of our customers in U.S. dollars. Although the fluctuation of currency exchange rates may impact our customers, and thus indirectly impact us, we do not attempt to hedge this indirect and speculative risk. Our overseas operations consist primarily of international business operations in the Netherlands and the United Kingdom, design centers in Canada, India Finland and FranceFinland and small business development offices in Australia, China, Japan, Korea, Singapore and Taiwan. We monitor our foreign currency exposure; however, as of December 31, 2016,2019, we believe our foreign currency exposure is not material enough to warrant foreign currency hedging.
Item 8.Financial Statements and Supplementary Data
SeeRefer to Item 15, “Exhibits and Financial Statement Schedules”Schedules,” of this Form 10-K for required financial statements and supplementary data.
Item 9.Changes in and Disagreements with Accountants on Accounting and Financial Disclosure
None.
Item 9A.Controls and Procedures
Evaluation of Disclosure Controls and Procedures
We maintain disclosure controls and procedures designed to ensure that information required to be disclosed in the reports we file or submit pursuant to the Securities and Exchange Act of 1934 as amended (“Exchange Act”) is recorded, processed, summarized and reported within the time periods specified in the rules and forms of the Securities and Exchange Commission, and that such information is accumulated and communicated to our management, including our Chief Executive Officer and Chief Financial Officer, as appropriate, to allow timely decisions regarding required disclosure.
Management, with the participation of the Chief Executive Officer and Chief Financial Officer, evaluated the effectiveness of the design and operation of our disclosure controls and procedures as defined in Rules 13a-15(e) and 15d-15(e) of the Exchange Act as of the end of the period covered by this report. Based on this evaluation, our Chief Executive Officer and Chief Financial Officer have concluded that, as of December 31, 2016,2019, our disclosure controls and procedures were effective.
Management’s Report on Internal Control over Financial Reporting
Our management is responsible for establishing and maintaining adequate internal control over financial reporting as defined in Rules 13a-15(f) and 15d-15(f) under the Exchange Act. Our internal control over financial reporting is the process designed by, or under the supervision of, our Chief Executive Officer and Chief Financial Officer, and effected by our board of directors, management and other personnel, to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with generally accepted accounting principles, and includes those policies and procedures that:
(i)pertain to the maintenance of records that in reasonable detail accurately and fairly reflect our transactions and dispositions of assets;


(ii)provide reasonable assurance that transactions are recorded as necessary to permit preparation of financial statements in accordance with generally accepted accounting principles, and that our receipts and expenditures are being made only in accordance with the authorization of our management and directors; and
(iii)provide reasonable assurance regarding prevention or timely detection of unauthorized acquisition, use or disposition of our assets that could have a material effect on the financial statements.
Because of its inherent limitations, internal control over financial reporting may not prevent or detect misstatements. Also, projections of any evaluation of effectiveness to future periods are subject to the risk that controls may become inadequate because of changes in conditions, or that the degree of compliance with the policies or procedures may deteriorate.


Under the supervision and with the participation of our management, including our Chief Executive Officer and Chief Financial Officer, we conducted an assessment of the effectiveness of our internal control over financial reporting as of December 31, 2016.2019. In making this assessment, our management used the criteria set forth in Internal Control — Integrated Framework (2013) issued by the Committee of Sponsoring Organizations of the Treadway Commission (“COSO”). Based on the results of this assessment, management has concluded that, as of December 31, 2016,2019, our internal control over financial reporting was effective based on the criteria in Internal Control — Integrated Framework (2013) issued by the COSO.
The Company's management hasUnder guidelines established by the SEC, companies are permitted to exclude acquisitions from their assessment of internal control over financial reporting during the first year of an acquisition while integrating the acquired company. We have excluded SCSNorthwest Logic, Inc. and the Memory Interconnect BusinessSecure Silicon IP and Protocols businesses of Verimatrix (the “acquired entities”) from itsour assessment of internal control over financial reporting as of December 31, 2016,2019 because they were acquired by the Companyus in purchase business combinations during 2016. Combined2019. The acquired entities are wholly-owned subsidiaries whose total assets and total revenues excluded from our assessment of these acquisitionsinternal control over financial reporting collectively represent approximately 4%1% and 10%1%, respectively, of the related consolidated financial statement amounts as of and for the year ended December 31, 2016.2019. 
The effectiveness of our internal control over financial reporting as of December 31, 20162019 has been audited by PricewaterhouseCoopers, LLP, an independent registered public accounting firm, as stated in their report which appears herein.
Changes in Internal Control Over Financial Reporting
There waswere no changechanges in internal control over financial reporting (as defined in Rules 13a-15(f) and 15d-15(f) of the Exchange Act) during the last fiscal quarter that hashave materially affected, or isare reasonably likely to materially affect, our internal control over financial reporting.
Item 9B.Other Information
None.

PART III
Item 10.Directors, Executive Officers and Corporate Governance
The information responsive to this item is incorporated herein by reference to our Proxy Statement for our 20172020 annual meeting of stockholders to be filed with the Securities and Exchange Commission pursuant to Regulation 14A not later than 120 days after the end of the fiscal year covered by this Annual Report on Form 10-K. The information under the heading “Our Executive Officers” in Part I, Item 1 of this Annual Report on Form 10-K is also incorporated herein by reference.
We have a Code of Business Conduct and Ethics for all of our directors, officers and employees. Our Code of Business Conduct and Ethics is available on our website at http://investor.rambus.com/corporate-governance-document.cfm?DocumentID=8379.default.aspx?SectionId=7d08773c-336a-43c5-b0ff-5b190f1901eb&LanguageId=1. To date, there have been no waivers under our Code of Business Conduct and Ethics. We will post any amendments or waivers, if and when granted, of our Code of Business Conduct and Ethics on our website.
Item 11.Executive Compensation
The information responsive to this item is incorporated herein by reference to our Proxy Statement for our 20172020 annual meeting of stockholders to be filed with the Securities and Exchange Commission pursuant to Regulation 14A not later than 120 days after the end of the fiscal year covered by this Annual Report on Form 10-K.
Item 12.Security Ownership of Certain Beneficial Owners and Management and Related Stockholder Matters
The information responsive to this item is incorporated herein by reference to our Proxy Statement for our 20172020 annual meeting of stockholders to be filed with the Securities and Exchange Commission pursuant to Regulation 14A not later than 120 days after the end of the fiscal year covered by this Annual Report on Form 10-K.
Item 13.Certain Relationships and Related Transactions, and Director Independence
The information responsive to this item is incorporated herein by reference to our Proxy Statement for our 20172020 annual meeting of stockholders to be filed with the Securities and Exchange Commission pursuant to Regulation 14A not later than 120 days after the end of the fiscal year covered by this Annual Report on Form 10-K.


Item 14.Principal Accountant Fees and Services
The information responsive to this item is incorporated herein by reference to our Proxy Statement for our 20172020 annual meeting of stockholders to be filed with the Securities and Exchange Commission pursuant to Regulation 14A not later than 120 days after the end of the fiscal year covered by this Annual Report on Form 10-K.



PART IV
Item 15.Exhibits and Financial Statement Schedules
(a)    (1) Financial Statements
The following consolidated financial statements of the Registrant and Report of PricewaterhouseCoopers LLP, Independent Registered Public Accounting Firm, are included herewith:
 Page
(a)    (2) Financial Statement Schedule
All schedules are omitted because they are not applicable or the required information is shown in the Consolidated Financial Statements or the notes thereto.



Report of Independent Registered Public Accounting Firm

To the Board of Directors and Stockholders of Rambus Inc.:

Opinions on the Financial Statements and Internal Control over Financial Reporting
In our opinion,
We have audited the accompanying consolidated financial statements listed in the index appearing under Item 15(a)(1) present fairly, in all material respects, the financial positionbalance sheets of Rambus Inc. and its subsidiaries at(the “Company”) as of December 31, 20162019 and December 31, 2015,2018, and the resultsrelated consolidated statements of their operations, of comprehensive income (loss), of stockholders’ equity and theirof cash flows for each of the three years in the period ended December 31, 20162019, including the related notes (collectively referred to as the “consolidated financial statements”). We also have audited the Company's internal control over financial reporting as of December 31, 2019, based on criteria established in Internal Control - Integrated Framework (2013) issued by the Committee of Sponsoring Organizations of the Treadway Commission (COSO).
In our opinion, the consolidated financial statements referred to above present fairly, in all material respects, the financial position of the Company as of December 31, 2019 and 2018, and the results of its operations and its cash flows for each of the three years in the period ended December 31, 2019 in conformity with accounting principles generally accepted in the United States of America. Also in our opinion, the Company maintained, in all material respects, effective internal control over financial reporting as of December 31, 2016,2019, based on criteria established in Internal Control - Integrated Framework (2013)issued by the Committee of Sponsoring Organizations ofCOSO.
Changes in Accounting Principles
As discussed in Notes 3 and 2 to the Treadway Commission (COSO). consolidated financial statements, respectively, the Company changed the manner in which it accounts for leases in 2019 and the manner in which it accounts for revenues from contracts with customers in 2018.
Basis for Opinions
The Company's management is responsible for these consolidated financial statements, for maintaining effective internal control over financial reporting, and for its assessment of the effectiveness of internal control over financial reporting, included in Management'sManagement’s Report on Internal Control over Financial Reporting appearing under Item 9A. Our responsibility is to express opinions on thesethe Company’s consolidated financial statements and on the Company's internal control over financial reporting based on our integrated audits. We are a public accounting firm registered with the Public Company Accounting Oversight Board (United States) (PCAOB) and are required to be independent with respect to the Company in accordance with the U.S. federal securities laws and the applicable rules and regulations of the Securities and Exchange Commission and the PCAOB.
We conducted our audits in accordance with the standards of the Public Company Accounting Oversight Board (United States).PCAOB. Those standards require that we plan and perform the audits to obtain reasonable assurance about whether the consolidated financial statements are free of material misstatement, whether due to error or fraud, and whether effective internal control over financial reporting was maintained in all material respects.
Our audits of the consolidated financial statements included performing procedures to assess the risks of material misstatement of the consolidated financial statements, whether due to error or fraud, and performing procedures that respond to those risks. Such procedures included examining, on a test basis, evidence supportingregarding the amounts and disclosures in the consolidated financial statements, assessingstatements. Our audits also included evaluating the accounting principles used and significant estimates made by management, andas well as evaluating the overall presentation of the consolidated financial statement presentation.statements. Our audit of internal control over financial reporting included obtaining an understanding of internal control over financial reporting, assessing the risk that a material weakness exists, and testing and evaluating the design and operating effectiveness of internal control based on the assessed risk. Our audits also included performing such other procedures as we considered necessary in the circumstances. We believe that our audits provide a reasonable basis for our opinions.
As described in Management’s Report on Internal Control over Financial Reporting, management has excluded Northwest Logic, Inc. and the Secure Silicon IP and Protocols businesses of Verimatrix (the “acquired entities”) from its assessment of internal control over financial reporting as of December 31, 2019 because they were acquired by the Company in purchase business combinations during 2019. We have also excluded the acquired entities from our audit of internal control over financial reporting. The acquired entities are wholly-owned subsidiaries whose total assets and total revenues excluded from management’s assessment and our audit of internal control over financial reporting collectively represent approximately 1% and 1%, respectively, of the related consolidated financial statement amounts as of and for the year ended December 31, 2019.

Definition and Limitations of Internal Control over Financial Reporting
A company’s internal control over financial reporting is a process designed to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with generally accepted accounting principles. A company’s internal control over financial reporting includes those policies and procedures that (i) pertain to the maintenance of records that, in reasonable detail, accurately and fairly reflect the transactions and dispositions of the assets of the company; (ii) provide reasonable assurance that transactions are recorded as necessary to permit preparation of financial statements in accordance with generally accepted accounting principles, and that receipts and expenditures of the company are being made only in accordance with authorizations of management and directors of the company; and (iii) provide reasonable assurance regarding prevention or timely detection of unauthorized acquisition, use, or disposition of the company’s assets that could have a material effect on the financial statements.

Because of its inherent limitations, internal control over financial reporting may not prevent or detect misstatements. Also, projections of any evaluation of effectiveness to future periods are subject to the risk that controls may become inadequate because of changes in conditions, or that the degree of compliance with the policies or procedures may deteriorate.

Critical Audit Matters

The critical audit matters communicated beloware mattersarising from the current period audit of the consolidated financial statements that were communicated or required to be communicated to the audit committee and that (i) relate to accounts or disclosures that are material to theconsolidated financial statements and (ii) involved our especially challenging, subjective, or complex judgments. The communication of critical audit matters does not alter in any way our opinion on the consolidatedfinancial statements, taken as a whole, and we are not, by communicating the critical audit matters below, providing separate opinions on the critical audit matters or on the accounts or disclosures to which they relate.

Valuation of Existing Technology Intangible Assets Acquired from the Northwest Logic, Inc. and Secure Silicon IP and Protocols acquisitions

As described in Notes 2 and 21 to the consolidated financial statements, during the year ended December 31, 2019, the Company completed the acquisitions of Northwest Logic, Inc. and Secure Silicon IP and Protocols businesses for total considerations of $21.9 million and $46.8 million, respectively, of which $8.1 million and $21.6 million, respectively, of existing technology intangible assets were recorded. The fair value of the assets acquired was determined by management primarily by using the multi-period excess earnings method under the income approach. This method reflects the present value of the projected cash flows that are expected to be generated by the existing technologies less charges representing the contribution of other assets to those cash flows. Significant estimates and assumptions in estimating the fair value of the existing technologies include revenue growth rates, operating expense margins, technology obsolescence rates, and discount rates.

The principal considerations for our determination that performing procedures relating to the valuation of the existing technology intangible assets acquired in the acquisitions of Northwest Logic, Inc. and Secure Silicon IP and Protocols businesses is a critical audit matter are there was significant judgment by management when determining the valuation of the existing technology intangibles assets, which in turn led to a high degree of auditor judgment, subjectivity and effort in performing procedures and evaluating audit evidence related to the revenue growth rates, operating expense margins, technology obsolescence rates, and discount rate assumptions used in the valuation of the existing technology intangible assets . In addition, the audit effort involved the use of professionals with specialized skill and knowledge.

Addressing the matter involved performing procedures and evaluating audit evidence in connection with forming our overall opinion on the consolidated financial statements. These procedures included testing the effectiveness of controls relating to the acquisition accounting, including controls over management’s valuation of the existing technologies intangible assets acquired in the acquisitions of Northwest Logic, Inc., and Secure Silicon IP and Protocols businesses. These procedures also included, among others, reading the purchase agreements and testing management’s process for determining the fair value of the existing technology intangible assets, including evaluating the appropriateness of the valuation method, testing the completeness and accuracy of underlying data used in the estimate, and evaluating the reasonableness of the significant assumptions, including revenue growth rates, operating expense margins, technology obsolescence rates, and discount rates. Evaluating the reasonableness of the revenue growth rates and the operating expense margins involved considering the past performance of the acquired businesses, actual arrangements subsequent to the acquisitions and industry data. Professionals with specialized skill and knowledge were used to assist in evaluating the appropriateness of valuation method and the reasonableness of the technology obsolescence rates and the discount rates.
Revenue Recognition - License and Customization Services Revenue

As described in Management’s Report on Internal Control over Financial Reporting, management has excluded Smart Card Software Limited (“SCS”) andNote 4 to the Memory Interconnect Business from its assessment of internal control overconsolidated financial reporting as of December 31, 2016 because they were acquired bystatements, the Company in separate purchase business combinations duringrecognizes license and customization services revenue based on an over time model, measured using the fiscal year ended December 31, 2016. We have also excluded SCSinput method. License and the Memory Interconnect Business from our auditcustomization services revenue is reported as part of internal control over financial reporting. SCScontract and the Memory Interconnect Business are wholly owned subsidiaries, whose total assets and total revenues represent 4% and 10%, respectively, of the related consolidated financial statement amounts as of andother revenue which was $28 million for the year ended December 31, 2016.2019. Due to the nature of the work performed in these arrangements, the estimation of the over time model is complex and involves significant judgment. The key factor reviewed by management to estimate costs to complete each contract is the estimated man-months necessary to complete the project.

The principal considerations for our determination that performing procedures relating to revenue recognition for license and customization revenue is a critical audit matter are there was significant judgment made by management to determine the estimated man-months necessary to contract completion for each contract, which in turn led to a high degree of auditor judgment, subjectivity and effort in performing procedures and evaluating audit evidence related to management’s estimate of man-months necessary to complete each project.

Addressing the matter involved performing procedures and evaluating audit evidence in connection with forming our overall opinion on the consolidated financial statements. These procedures included testing the effectiveness of controls relating to the Company’s license and customization services revenue recognition process, including controls over management’s determination of the estimate of total man-months to complete each contract. The procedures also included, among others, for a sample of contracts, testing management’s process for determining the estimate of total man-months. Evaluating management’s assumption related to the estimate of man-months involved (i) performing a comparison of the estimated man-months to completed projects of similar size and (ii) evaluating the timely identification of circumstances which may warrant a modification to a previous cost estimate, including an assessment of total man-months.

Relative Fair Value Measurement Related to the Goodwill Allocation of the Payments and Ticketing Businesses and the Retained Business.

As described in Notes 6 and 17 to the consolidated financial statements, the Company entered into a share purchase agreement with Visa International Service Association (the “Purchaser”), pursuant to which the Purchaser agreed to acquire all of the outstanding shares of the Company’s subsidiary, Smart Card Software Limited, which comprises the Company’s Payments and Ticketing businesses, which was part of the Company’s former Rambus Security Division (“RSD”) segment. The Company measured these businesses at the lower of their carrying value or fair value less any costs to sell, and recognized a cumulative impairment of approximately $7.4 million during the year ended December 31, 2019. In the second quarter of 2019, in order to determine the impairment loss, the Company performed a relative fair value measurement to allocate goodwill to the business units between the disposed Payments and Ticketing businesses and the retained business, which includes Cryptography Research, Inc (“CRI”), which was part of the former RSD segment. The goodwill allocated to the disposed Payments and Ticketing businesses was $54.5 million. The fair value of the retained business was estimated by management using a discounted cash flow model. The Company’s cash flow projections for the retained business included significant judgments and assumptions relating to revenue growth rates, projected operating income and the discount rate.

The principal considerations for our determination that performing procedures relating to the fair value measurement of the retained business unit is a critical audit matter are there was significant judgment made by management when developing the fair value measurement of the retained business unit, which in turn led to a high degree of auditor judgment, subjectivity and effort in performing procedures and evaluating audit evidence related to management’s cash flow projections, including significant assumptions relating to revenue growth rates, projected operating income, and the discount rate.

Addressing the matter involved performing procedures and evaluating audit evidence in connection with forming our overall opinion on the consolidated financial statements. These procedures included testing the effectiveness of controls relating to management’s assessment of the relative fair value measurement of the retained business unit. The procedures also included, among others, testing management’s process for developing the fair value measurement for the retained business unit; evaluating the appropriateness of the discounted cash flow model; testing the completeness, accuracy, and relevance of underlying data used in the model; and evaluating the reasonableness of the significant assumptions used by management, including revenue growth rates, projected operating income and the discount rate. Evaluating management’s assumptions related to revenue growth rates and projected operating income involved evaluating whether the assumptions used by management were reasonable considering (i) the current and past performance of the retained business unit, (ii) the consistency with external market and industry data, and (iii) whether these assumptions were consistent with evidence obtained in other areas of the audit and the prior year audit.

/s/ PricewaterhouseCoopers LLP 
San Jose, California 
February 17, 201726, 2020
We have served as the Company’s auditor since 1991. 



RAMBUS INC.
CONSOLIDATED BALANCE SHEETS
December 31,
December 31,2019 2018
2016 2015   
(In thousands, except shares and per share amounts)(In thousands, except shares and per share amounts)
ASSETS      
Current assets:      
Cash and cash equivalents$135,294
 $143,764
$102,176
 $115,924
Marketable securities36,888
 143,942
305,488
 161,840
Accounts receivable21,099
 16,408
44,039
 50,863
Unbilled receivables184,366
 176,613
Inventories10,086
 6,772
Prepaids and other current assets17,867
 10,396
18,524
 15,738
Inventories5,633
 1,080
Total current assets216,781
 315,590
664,679
 527,750
Intangible assets, net132,388
 64,266
54,900
 59,936
Goodwill204,794
 116,899
183,465
 207,178
Property, plant and equipment, net58,442
 56,616
44,714
 57,028
Operating lease right-of-use assets37,020
 
Deferred tax assets168,342
 162,485
4,574
 4,435
Unbilled receivables, long-term343,703
 497,003
Other assets2,749
 2,165
5,931
 7,825
Total assets$783,496
 $718,021
$1,338,986
 $1,361,155
LIABILITIES & STOCKHOLDERS’ EQUITY      
Current liabilities:      
Accounts payable$9,793
 $4,096
$9,549
 $7,392
Accrued salaries and benefits14,177
 12,278
20,291
 16,938
Deferred revenue16,932
 5,780
11,947
 19,374
Income taxes payable, short-term19,142
 16,390
Operating lease liabilities6,357
 
Other current liabilities10,399
 6,212
18,893
 9,191
Total current liabilities51,301
 28,366
86,179
 69,285
Convertible notes, long-term126,167
 119,418
148,788
 141,934
Long-term imputed financing obligation38,029
 38,625

 36,297
Long-term operating lease liabilities39,889
 
Long-term income taxes payable60,094
 77,280
Deferred tax liabilities11,600
 
13,846
 18,960
Other long-term liabilities3,617
 5,079
19,272
 5,287
Total liabilities230,714
 191,488
368,068
 349,043
Commitments and contingencies (Notes 11 and 17)
 
Commitments and contingencies (Notes 10, 13 and 20)

 

Stockholders’ equity:      
Convertible preferred stock, $.001 par value:      
Authorized: 5,000,000 shares; Issued and outstanding: no shares at December 31, 2016 and December 31, 2015
 
Authorized: 5,000,000 shares; Issued and outstanding: no shares at December 31, 2019 and December 31, 2018
 
Common Stock, $.001 par value:      
Authorized: 500,000,000 shares; Issued and outstanding: 111,053,734 shares at December 31, 2016 and 109,287,591 shares at December 31, 2015111
 109
Authorized: 500,000,000 shares; Issued and outstanding: 112,131,352 shares at December 31, 2019 and 109,017,708 shares at December 31, 2018112
 109
Additional paid in capital1,181,230
 1,130,368
1,261,142
 1,226,588
Accumulated deficit(615,051) (604,317)(290,244) (204,294)
Accumulated other comprehensive income (loss)(13,508) 373
Accumulated other comprehensive loss(92) (10,291)
Total stockholders’ equity552,782
 526,533
970,918
 1,012,112
Total liabilities and stockholders’ equity$783,496
 $718,021
$1,338,986
 $1,361,155
See Notes to Consolidated Financial Statements

RAMBUS INC.
CONSOLIDATED STATEMENTS OF OPERATIONS
Years Ended December 31,
Years Ended December 31,2019 2018 2017
2016 2015 2014     
(In thousands, except per share amounts)(In thousands, except per share amounts)
Revenue:          
Royalties$264,614
 $262,415
 $271,521
$90,785
 $130,452
 $289,594
Product revenue72,972
 38,690
 36,509
Contract and other revenue71,983
 33,863
 25,037
60,270
 62,059
 66,993
Total revenue336,597
 296,278
 296,558
224,027
 231,201
 393,096
Operating costs and expenses:          
Cost of revenue*67,090
 45,344
 41,947
Cost of product revenue*27,156
 18,299
 23,783
Cost of contract and other revenue24,219
 35,402
 55,364
Research and development*129,844
 111,110
 110,025
156,815
 158,339
 149,135
Sales, general and administrative*95,145
 70,554
 74,770
104,116
 103,911
 110,940
Restructuring charges
 3,576
 39
Impairment of in-process research and development intangible asset18,300
 
 
Change in contingent consideration liability(6,845) 
 
Restructuring and other charges8,821
 2,217
 
Loss on divestiture7,439
 
 
Gain from sale of intellectual property
 (3,686) (3,529)
 
 (533)
Gain from settlement(579) (2,040) (2,040)
Total operating costs and expenses302,955
 224,858
 221,212
328,566
 318,168
 338,689
Operating income33,642
 71,420
 75,346
Operating income (loss)(104,539) (86,967) 54,407
Interest income and other income (expense), net1,740
 1,224
 (276)27,375
 32,621
 1,384
Loss on extinguishment of debt
 
 (1,082)
Interest expense(12,745) (12,413) (24,820)(9,852) (16,282) (13,720)
Interest and other income (expense), net(11,005) (11,189) (25,096)17,523
 16,339
 (13,418)
Income before income taxes22,637
 60,231
 50,250
Provision for (benefit from) income taxes15,817
 (151,157) 24,049
Net income$6,820
 $211,388
 $26,201
Net income per share:     
Income (loss) before income taxes(87,016) (70,628) 40,989
Provision for income taxes3,403
 87,329
 63,851
Net loss$(90,419) $(157,957) $(22,862)
Net loss per share:     
Basic$0.06
 $1.84
 $0.23
$(0.81) $(1.46) $(0.21)
Diluted$0.06
 $1.80
 $0.22
$(0.81) $(1.46) $(0.21)
Weighted average shares used in per share calculations:          
Basic110,162
 114,814
 114,318
110,948
 108,450
 110,198
Diluted113,140
 117,484
 117,624
110,948
 108,450
 110,198

* Includes stock-based compensation:     
Cost of product revenue$4
 $8
 $78
Research and development$11,032
 $12,582
 $12,185
Sales, general and administrative$15,440
 $9,146
 $15,140
* Includes stock-based compensation:     
Cost of revenue$56
 $63
 $44
Research and development$9,165
 $6,762
 $7,216
Sales, general and administrative$11,792
 $8,271
 $7,470

See Notes to Consolidated Financial Statements



RAMBUS INC.
CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS)
Years Ended December 31,Years Ended December 31,
2016 2015 20142019 2018 2017
(In thousands)     
Net income$6,820
 $211,388
 $26,201
(In thousands)
Net loss$(90,419) $(157,957) $(22,862)
Other comprehensive income (loss):
 
 

 
 
Foreign currency translation adjustment(13,485) 9
 
10,145
 (4,447) 7,798
Unrealized gain (loss) on marketable securities, net of tax(396) 766
 (97)54
 (747) 613
Total comprehensive income (loss)$(7,061) $212,163
 $26,104
Total comprehensive loss$(80,220) $(163,151) $(14,451)
See Notes to Consolidated Financial Statements


RAMBUS INC.
CONSOLIDATED STATEMENTS OF STOCKHOLDERS’ EQUITY
Common Stock Additional Paid-in Capital Accumulated Deficit Accumulated Other Comprehensive Gain (Loss)      Additional Paid-in Capital Accumulated Deficit Accumulated Other Comprehensive Gain (Loss)  
Shares Amount TotalCommon Stock  
(In thousands)Shares Amount Total
Balances at December 31, 2013113,459 $113
 $1,128,148
 $(787,727) $(305) $340,229
Net income
 
 
 26,201 
 26,201
Unrealized loss on marketable securities, net of tax
 
 
 
 (97) (97)
Issuance of common stock upon exercise of options, equity stock and employee stock purchase plan1,703 2 10,557 
 
 10,559
Stock-based compensation
 
 14,730 
 
 14,730
Balances at December 31, 2014115,162
115
1,153,435
(761,526)
(402) 391,622
Net income
 
 
 211,388
 
 211,388
           
(In thousands)
Balances at December 31, 2016111,054
$111

$1,181,230

$(615,051)
$(13,508) $552,782
Net loss
 
 
 (22,862) 
 (22,862)
Foreign currency translation adjustment
 
 
 
 9 9
 
 
 
 7,798
 7,798
Unrealized gain on marketable securities, net of tax
 
 
 
 766 766
 
 
 
 613 613
Issuance of common stock upon exercise of options, equity stock and employee stock purchase plan1,938 2 13,075 
 
 13,0772,727 3 10,730 
 
 10,733
Repurchase and retirement of common stock under repurchase plan, including prepayment under accelerated share repurchase program(7,812) (8) (45,926) (54,179) 
 (100,113)
Repurchase and retirement of common stock under repurchase plan(4,017) (4) (13,477) (36,557) 
 (50,038)
Stock-based compensation
 
 15,096 
 
 15,096

 
 27,403 
 
 27,403
Tax shortfall from stock option forfeitures
 
 (5,312) 
 
 (5,312)
Balances at December 31, 2015109,288 109 1,130,368 (604,317) 373 526,533
Net income
 
 
 6,820
 
 6,820
Equity component of 1.375% convertible notes, net
 
 33,913
 
 
 33,913
Purchase of convertible note hedges
 
 (33,523) 
 
 (33,523)
Issuance of warrants
 
 23,173
 
 
 23,173
Repurchase of 1.125% convertible notes
 
 (16,651) 
 
 (16,651)
Cumulative effect adjustment from adoption of ASU 2016-09
 
 
 38,243
 
 38,243
Balances at December 31, 2017109,764 110 1,212,798 (636,227) (5,097) 571,584
Net loss
 
 
 (157,957) 
 (157,957)
Foreign currency translation adjustment
 
 
 
 (13,485) (13,485)
 
 
 
 (4,447) (4,447)
Unrealized loss on marketable securities, net of tax
 
 
 
 (396) (396)
 
 
 
 (747) (747)
Issuance of common stock upon exercise of options, equity stock and employee stock purchase plan2,502 3 12,294 
 
 12,2972,616 3 4,627 
 
 4,630
Repurchase and retirement of common stock under repurchase plan(736) (1) 17,555
 (17,554) 
 
(3,786) (4) (12,573) (37,456) 
 (50,033)
Stock-based compensation
 
 21,013 
 
 21,013
 
 21,736 
 
 21,736
Balances at December 31, 2016111,054 $111
 $1,181,230
 $(615,051) $(13,508) $552,782
Issuance of common stock in connection with the maturity of the 2018 Notes related to the settlement of the in-the-money conversion feature of the 2018 Notes424
 
 
 
 
 
Cumulative effect adjustment from adoption of ASU 2016-01
 
 
 1,058
 
 1,058
Cumulative effect adjustment from the adoption of ASC 606
 
 
 626,288
 
 626,288
Balances at December 31, 2018109,018 109 1,226,588 (204,294) (10,291) 1,012,112
Net loss
 
 
 (90,419) 
 (90,419)
Foreign currency translation adjustment
 
 
 
 10,145
 10,145
Unrealized gain on marketable securities, net of tax
 
 
 
 54
 54
Issuance of common stock upon exercise of options, equity stock and employee stock purchase plan3,113
 3
 8,078
 
 
 8,081
Stock-based compensation
 
 26,476
 
 
 26,476
Cumulative effect adjustment from the adoption of ASC 842
 
 
 4,469
 
 4,469
Balances at December 31, 2019112,131 $112
 $1,261,142
 $(290,244) $(92) $970,918
See Notes to Consolidated Financial Statements

RAMBUS INC.
CONSOLIDATED STATEMENTS OF CASH FLOWS
Years Ended December 31,
Years Ended December 31,2019 2018 2017
2016 2015 2014     
(In thousands)(In thousands)
Cash flows from operating activities:          
Net income$6,820
 $211,388
 $26,201
Adjustments to reconcile net income to net cash provided by operating activities:     
Net loss$(90,419) $(157,957) $(22,862)
Adjustments to reconcile net loss to net cash provided by operating activities:     
Stock-based compensation21,013
 15,096
 14,730
26,476
 21,736
 27,403
Depreciation12,965
 12,379
 13,625
23,507
 10,745
 13,275
Amortization of intangible assets37,138
 25,074
 26,618
17,058
 29,341
 41,962
Non-cash interest expense and amortization of convertible debt issuance costs6,749
 6,372
 14,763
6,854
 9,243
 7,578
Impairment of in-process research and development intangible asset18,300
 
 
Change in contingent consideration liability(6,845) 
 
Impairment of investment in non-marketable equity security
 
 600
Loss on extinguishment of debt
 
 1,082
Deferred tax (benefit) provision(7,116) (172,706) 2,310
(1,816) 79,954
 39,535
Excess tax benefits from stock-based compensation(1,196) (747) (481)
Non-cash restructuring
 583
 

 670
 
Gain from sale of intellectual property and property, plant and equipment, net
 (3,670) (3,529)
Effect of exchange rate on assumed cash liability from acquisition(1,558) 
 
Change in operating assets and liabilities, net of effects of acquisitions:     
Loss on divestiture7,439
 
 
Gain from sale of assets held for sale
 (1,266) 
Gain from sale of marketable equity security
 (291) 
Loss on equity investment696
 67
 
Loss from disposal of property, plant and equipment157
 395
 227
Change in operating assets and liabilities, net of effects of acquisitions and divestiture:     
Accounts receivable5,797
 (10,407) (3,750)4,994
 (24,933) (1,110)
Prepaids and other assets(6,205) (1,042) 476
Unbilled receivables151,513
 145,164
 
Prepaid expenses and other assets4,064
 (4,084) 4,354
Inventories1,748
 (3,412) (2,907)(3,353) (1,856) 473
Accounts payable2,373
 (2,621) 2,006
2,934
 (2,268) (651)
Accrued salaries and benefits and other accrued liabilities(4,758) (2,952) (17,862)7,135
 (3,221) 4,703
Income taxes payable(15,925) (14,550) 861
Deferred revenue7,313
 3,107
 3,667
(3,497) 228
 607
Operating lease liabilities(9,282) 
 
Net cash provided by operating activities92,538
 76,442
 76,467
128,535
 87,117
 117,437
Cash flows from investing activities:
 
 

 
 
Purchases of property, plant and equipment(8,556) (6,132) (7,204)(6,472) (10,762) (9,385)
Acquisition of intangible assets
 (350) (120)
Purchases of marketable securities(54,869) (157,811) (240,281)(657,433) (282,117) (102,497)
Maturities of marketable securities110,081
 112,721
 118,735
507,385
 223,079
 32,048
Proceeds from sale of marketable securities50,546
 48,380
 24,986
6,758
 
 4,450
Proceeds from sale of intellectual property and property, plant and equipment, net113
 3,933
 5,859
Acquisition of businesses, net of cash acquired(202,523) 
 
Net cash provided by (used in) investing activities(105,208) 1,091
 (97,905)
Proceeds from sale of property and property, plant and equipment29
 10
 33
Proceeds from divestiture, net of cash disposed76,039
 
 
Proceeds from sale of assets held for sale


 3,754
 
Proceeds from sale of equity security
 1,350
 
Investment in privately-held company(1,000) (3,000) 
Acquisitions of businesses, net of cash acquired(66,780) 
 
Net cash used in investing activities(141,474) (68,036) (75,471)
Cash flows from financing activities:
 
 

 
 
Proceeds from issuance of 1.375% convertible notes
 
 172,500
Issuance costs related to issuance of 1.375% convertible notes
 
 (3,277)
Payments for convertible note hedges
 
 (33,523)
Proceeds from issuance of warrants
 
 23,173
Repayment of 1.125% convertible notes
 (81,207) (72,257)
Proceeds received from issuance of common stock under employee stock plans15,436
 13,783
 11,079
15,104
 11,402
 15,826
Payments under installment payment arrangement
 (1,717) (1,773)(8,379) 
 
Principal payments against financing lease obligation(661) (478) (322)
 (1,080) (860)
Payment of additional purchase consideration from acquisition(10,206) 
 
Repurchase and retirement of common stock, including prepayment under accelerated share repurchase program
 (100,113) 

 (50,033) (50,038)
Excess tax benefits from stock-based compensation1,196
 747
 481
Repayment of senior convertible notes
 
 (172,500)
Payments of taxes on restricted stock units(7,023) (6,766) (5,099)
Net cash provided by (used in) financing activities5,765
 (87,778) (163,035)(298) (127,684) 46,445
Effect of exchange rate changes on cash and cash equivalents(1,565) (117) (97)(497) (989) 2,139
Net decrease in cash and cash equivalents(8,470) (10,362) (184,570)
Cash and cash equivalents at beginning of year143,764
 154,126
 338,696
Cash and cash equivalents at end of year$135,294
 $143,764
 $154,126
Net increase (decrease) in cash, cash equivalents and restricted cash(13,734) (109,592) 90,550
Cash, cash equivalents and restricted cash at beginning of year116,252
 225,844
 135,294
Cash, cash equivalents and restricted cash at end of year$102,518
 $116,252
 $225,844
     
The following table provides a reconciliation of the cash, cash equivalents and restricted cash balances as of December 31, 2019, December 31, 2018 and December 31, 2017:     
December 31,
2019
 December 31,
2018
 December 31,
2017
Cash and cash equivalents$102,176
 $115,924
 $225,844
Restricted cash342
 328
 
Cash, cash equivalents and restricted cash$102,518
 $116,252
 $225,844
          
Supplemental disclosure of cash flow information:          
Cash paid during the period for:          
Interest$1,553
 $1,553
 $5,861
$2,372
 $3,044
 $1,553
Income taxes, net of refunds$26,787
 $21,679
 $20,691
$17,835
 $23,581
 $22,733
Non-cash investing and financing activities:          
Property, plant and equipment received and accrued in accounts payable and other accrued liabilities$576
 $240
 $548
$29,844
 $8,225
 $1,092
Re-measurement of investment upon initial public offering$
 $1,264
 $
See Notes to Consolidated Financial Statements

RAMBUS INC.
NOTES TO CONSOLIDATED FINANCIAL STATEMENTS


1. Formation and Business of the Company
Rambus Inc. (the “Company” or “Rambus”) was incorporated in California in March 1990 and reincorporated in Delaware in March 1997. In addition to licensing, the Company is creating new business opportunities through offering products and services where its goal is to perpetuate strong company operating performance and long-term stockholder value. The Company generates revenue by licensing its inventions and solutions, selling its semiconductor products and providing services to market-leading companies.
WhileRambus is a premier Silicon IP and Chip provider, delivering high-speed interface and embedded security solutions to make data faster and safer. With 30 years of innovation, the Company has historically focused its effortscontinues to develop and license the foundational technology essential to all modern system on the development of technologies for memory, SerDeschips (SoCs) and other chip interfaces, the Company has expanded its portfolio of inventions and solutions to address chip and system security, mobile payments and smart ticketing.computing systems. The Company intends to continue its growth into new technology fields, consistent with its mission to create value through its innovationsdelivers a broad range of semiconductor solutions including architecture licenses, high-speed physical and to make those technologies available through the shipment of products, the provision of services, as well as the Company's licensing business models. Key to its efforts continues to be hiringdigital controller Interface IP cores, Security IP cores and retaining world-class inventors, scientistsprotocols, and engineers to lead the development and deployment of inventions and technology solutions for its fields of focus.memory interface Chips.
2. Summary of Significant Accounting Policies
Financial Statement Presentation
The accompanying consolidated financial statements include the accounts of Rambus and its wholly owned subsidiaries. All intercompany accounts and transactions have been eliminated in the accompanying consolidated financial statements. Investments in entities with more than 20% ownership by Rambus and in which Rambus has the ability to significantly influence the operations of the investee (but not control) are accounted for using the equity method and are included in other assets.
Use of Estimates
The preparation of financial statements in conformity with generally accepted accounting principles requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenue and expenses during the reporting period. Actual results could differ from those estimates.
Reclassifications
Certain prior year balances were reclassified to conform to the current year’s presentation. None of these reclassifications had an impact on reported net income or cash flows for any of the periods presented. Refer to Note 9 "Balance Sheet Details" and Note 10 "Convertible Notes" for details.
Revenue Recognition
Overview
Rambus recognizesThe Company adopted the New Revenue Standard on January 1, 2018 and all the related amendments using the modified retrospective method. The Company recognized the cumulative effect of initially applying the new revenue when persuasive evidence ofstandard as an arrangement exists, Rambus has delivered the product or performed the service, the fee is fixed or determinable and collection is reasonably assured. If any of these criteria are not met, Rambus defers recognizing the revenue until such time as all criteria are met. Determination of whether or not these criteria have been met may require the Company to make judgments, assumptions and estimates based upon current information and historical experience.
For arrangements that involve the delivery of more than one element, each license, service or product is evaluated to determine whether it qualifies as a separate unit of accounting. This determination is based on whether the deliverable has “stand-alone value”adjustment to the customer.opening balance of accumulated deficit as of January 1, 2018. The consideration that is fixed or determinable is then allocatedcomparative information for 2017 has not been recast and continues to each separate unit ofbe reported under the accounting based on the relative selling price of each deliverable. Rambus determines the relative selling price for a deliverable based on its best estimate of selling price (“BESP”). Except for some revenue associated to the acquisition of Bell Identification Ltd., Rambus has determined that vendor-specific objective evidence of selling price for each deliverable is not available as it lacks a consistent number of standalone sales and third-party evidence is not a practical alternative due to differencesstandards in its service offerings compared to other parties and the availability of relevant third-party pricing information. Rambus determined BESP by considering its overall pricing objectives and market conditions. Significant pricing practices taken into consideration include discounting practices, the size and volume of transactions, the customer demographic, the geographic area where services are sold, price lists, go-to-market strategy, historical standalone sales and contract prices. The determination of BESP is made through consultation with and approval by management, taking into consideration the go-to-

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market strategy. As the go-to-market strategies evolve, Rambus may modify its pricing practices in the future, which could result in changes in relative selling prices. In most cases, the relative values of the undelivered components are not material to the overall arrangement and are typically delivered within twelve months after the core product has been delivered. In such agreements, selling price is determined for each component and any difference between the total of the separate BESP and total contract consideration (i.e. discount) is allocated pro-rata across each of the components in the arrangement.
During the first quarter of 2016, the Company acquired Smart Card Software Ltd., which included Bell Identification Ltd. and Ecebs Ltd. which transact mostly in software and hosted services (SaaS) arrangements, respectively. For software arrangements that include multiple elements, including software licenses, professional services and maintenance services, Rambus allocates and defers revenue for the undelivered items (typically only the maintenance services) based on the fair value using vendor specific objective evidence (“VSOE”), and recognizes the difference between the total arrangement fee and the amount deferred for the undelivered item(s) as revenue. VSOE of fair value of each maintenance element is based on the contractual stated renewal rateeffect for that maintenance element. When VSOE of fair value does not exist for undelivered items, the entire arrangement fee is recognized ratably over the performance period. For hosted services arrangements, Rambus recognizes the arrangements over the service obligation period.
During 2016, the Company renamed its Cryptography Research Division ("CRD") organization to the Rambus Security Division ("RSD") and its Lighting and Display Technologies Division ("LDT") organization to Rambus Lighting Division ("RLD"). Rambus’ revenue consists of royalty revenue and contract and other revenue derived from Memory and Interface Division ("MID"), RSD and RLD operating segments. Royalty revenue consists of patent license and technology license royalties. Contract and other revenue consists of software license fees, engineering fees associated with integration of Rambus’ technology solutions into its customers’ related support and maintenance, as well as sale of products.
During 2013, the Company expanded its business strategy of monetizing its patent portfolio to include the sale of selected intellectual property. The Company's MID business continues to grow its patent portfolio and actively engages with various external parties to monetize the patent portfolio and explore new revenue opportunities. As the sales of such patents developed by the MID business unit under this expanded strategy represents a component of the Company's ongoing major or central operations, the Company records the related proceeds as revenue. The Company will recognize the revenue when there is persuasive evidence of a sales arrangement, fees are fixed or determinable, delivery has occurred and collectibility is reasonably assured. These requirements are generally fulfilled upon closing of the patent sale transaction.
Royalty Revenue
Rambus generally recognizes royalty revenue upon notification by its customers and when deemed collectible. The terms of the royalty agreements generally either require customers to give Rambus notification and to pay the royalties within a specified period or are based on a fixed royalty that is due within a specified period. Many of Rambus’ customers have the right to cancel their licenses. In such arrangements, revenue is only recognized to the extent that is consistent with the cancellation provisions. Cancellation provisions within such contracts generally provide for a prospective cancellation with no refund of fees already remitted by customers for products provided and payment for services rendered prior to the date of cancellation. Rambus has two types of royalty revenue: (1) patent license royalties and (2) technology license royalties.
Patent licenses - Rambus licenses its broad portfolio of patented inventions to companies who use these inventions in the development and manufacture of their own products. Such licensing agreements may cover the license of part, or all, of Rambus' patent portfolio. The contractual terms of the agreements generally provide for payments over an extended period of time. For the licensing agreements with fixed royalty payments, Rambus generally recognizes revenue from these arrangements as amounts become due. For the licensing agreements with variable royalty payments which can be based on either a percentage of sales or number of units sold, Rambus earns royalties at the time that the customers’ sales occur. Rambus’ customers, however, do not report and pay royalties owed for sales in any given quarter until after the conclusion of that quarter. As Rambus is unable to estimate the customers’ sales in any given quarter to determine the royalties due to Rambus, it recognizes royalty revenues based on royalties reported by customers during the quarter and when other revenue recognition criteria are met.
In addition, Rambus may enter into certain settlements of patent infringement disputes. The amount of consideration received upon any settlement (including but not limited to past royalty payments, future royalty payments and punitive damages) is allocated to each element of the settlement based on the fair value of each element. In addition, revenues related to past royalties are recognized upon execution of the agreement by both parties, provided that the amounts are fixed or determinable, there are no significant undelivered obligations and collectability is reasonably assured. Rambus does not recognize any revenues prior to execution of the agreement since there is no reliable basis on which it can estimate the amounts for royalties related to previous periods or assess collectability. Elements that are related to royalty revenue in nature (including

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but not limited to past royalty payments and future royalty payments) will be recorded as royalty revenue in the consolidated statements of operations. Elements that are not related to royalty revenue in nature (including but not limited to punitive damage and settlement) will be recorded as gain from settlement which is reflected as a separate line item within the operating expenses section in the consolidated statements of operations.
Technology licenses - Rambus develops proprietary and industry-standard products that it provides to its customers under technology license agreements. These arrangements include royalties, which can be based on either a percentage of sales or number of units sold. Rambus earns royalties on such licensed products sold worldwide by its customers at the time that the customers’ sales occur. Rambus’ customers, however, do not report and pay royalties owed for sales in any given quarter until after the conclusion of that quarter. As Rambus is unable to estimate the customers’ sales in any given quarter to determine the royalties due to Rambus, it recognizes royalty revenues based on royalties reported by customers during the quarter and when other revenue recognition criteria are met.
Contract and Other Revenue
Product revenue is recognized upon shipment of product to customers, net of accruals for estimated sales returns and allowances, which to date, have not been significant. However, some of the Company’s sales are made through distributors under arrangements that allow for price protection or rights of return on product unsold by the distributors. Product revenue on sales made through distributors with rights of return or price protection is deferred until the distributors sell the product to end customers. Sales to distributors are included in deferred revenue and the Company defers the related costs until sale to the end customers occurs. Price protection rights allow distributors the right to a credit in the event of declines in the price of the Company’s product that they hold prior to the sale to an end customer. In the event that the Company reduces the selling price of products held by distributors, deferred revenue related to distributors with price protection rights is reduced upon notification to the customer of the price change. The Company’s sales to direct customers are made primarily pursuant to standard purchase orders for delivery of products. The Company generally allows customers to cancel or change purchase orders within limited notice periods prior to the scheduled shipment.
For software arrangements that include multiple elements, including software licenses, professional services and maintenance services, Rambus allocates and defers revenue for the undelivered items (typically only the maintenance services) based on the fair value using vendor specific objective evidence (“VSOE”), and recognizes the difference between the total arrangement fee and the amount deferred for the undelivered item(s) as revenue. VSOE of fair value of each maintenance element is based on the contractual stated renewal rate for that maintenance element. When VSOE of fair value does not exist for undelivered items, the entire arrangement fee is recognized ratably over the performance period.
For software arrangements, the Company uses the percentage-of-completion method for contracts that involve the implementation of software solutions and that qualify for percentage-of-completion revenue accounting (e.g. software arrangements that contain a PCS element that has VSOE of fair value established and that have no refund rights that would allow a customer refunds of fees paid under the arrangement). Revenue is recognized based on man-days incurred during the reporting period as compared to the estimated total man- days necessary for each contract, not to exceed the billable project acceptances received, with deferral of corresponding contract costs, if applicable. Should a loss be anticipated on a contract, the full amount of the loss would be recorded when the loss is determinable. Maintenance and support revenue includes post-implementation customer support and the right to unspecified software updates and enhancements on a when and if available basis. The Company recognizes revenue from maintenance arrangements ratably overupon transfer of control of promised goods and services in an amount that reflects the periodconsideration it expects to receive in whichexchange for those goods and services. Substantially all of the goods and services are provided.distinct and are accounted for as separate performance obligations.

For development contracts relatedWhere an arrangement includes multiple performance obligations, the transaction price is allocated to licensesthese on a relative standalone selling price basis. The Company has established standalone selling prices for all of its solutionsofferings - specifically, the same pricing methodology is consistently applied to all licensing arrangements; all services offerings are priced within tightly controlled bands and all contracts that involve significant engineeringinclude support and integration services, the Company uses the proportional performance method. The measurement of progress to completion is based on actual man-months incurred during the reporting period, not to exceed the billable project acceptances received. Contract costs are recognized as incurred. Maintenance and support revenue includes minimal hours of post-implementation customer supportmaintenance state a renewal rate or price that is recognized ratably over the support period.

systematically enforced.
Cost of Revenue

Cost of revenue includes cost of professional services, materials, including cost of wafers processed by third-party foundries, cost associated with packaging and assembly, test and shipping, cost of personnel, including stock-based compensation, and equipment associated with manufacturing support, logistics and quality assurance, warranty cost,

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amortization of developedexisting technology, amortization of step-up values of inventory, write downwrite-down of inventories, amortization of production mask costs, overhead and an allocated portion of occupancy costs.

Leases
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The Company leases office space, domestically and internationally, under operating leases. The Company’s leases have remaining lease terms between one year and ten years. Operating leases are included in operating lease right-of-use (“ROU”) assets, operating lease liabilities, and long-term operating lease liabilities in the Company’s consolidated balance sheets. The Company does not have any finance leases. The Company determines if an arrangement is a lease, or contains a lease, at inception. The Company assesses all relevant facts and circumstances in making the determination of the existence of a lease. For leases with terms greater than 12 months, the Company records the related asset and obligation at the present value of lease payments over the term. Many of the Company’s leases include rental escalation clauses, renewal options and/or termination options that are factored into the determination of lease payments when appropriate. Leases with an initial term of 12 months or less are not recorded on the balance sheet, and the Company does not separate non-lease components from lease components. Operating lease costs are included in research and development and selling, general and administrative costs on the statement of operations.
Goodwill
Goodwill represents the excess of the purchase price over the fair value of the net tangible and identifiable intangible assets acquired in each business combination. Goodwill is not subject to amortization, but is subject to at least an annual assessment for impairment, applying a fair-value based test.impairment. The Company performs its impairment analysis of goodwill on an annual basis during the fourth quarter of the year unless conditions arise that warrant a more frequent evaluation.
GoodwillWhen goodwill is allocatedassessed for impairment, the Company has the option to perform an assessment of qualitative factors of impairment (optional assessment) prior to necessitating a quantitative impairment test. Should the variousoptional assessment be used for any given year, qualitative factors to consider for a reporting units which are generally operating segments. The goodwill impairmentunit include: cost factors; financial performance; legal, regulatory, contractual, political, business, or other factors; entity specific factors; industry and market considerations; macroeconomic conditions; and other relevant events and factors affecting the reporting unit. If the Company determines in the qualitative assessment that it is more likely than not that the fair value of the reporting unit is less than its carrying value, a quantitative test involvesis then performed. Otherwise, no further testing is required. For a two-step process. In the first step,reporting unit tested using a quantitative approach, the Company compares the fair value of eachthe reporting unit to itswith the carrying value. The fair valuesamount of the reporting units areunit, including goodwill. The fair value of the reporting unit is estimated using an income or discounted cash flows approach.
Under the income approach, the Company measures fair value of the reporting unit based on a projected cash flow method using a discount rate determined by its management which is commensurate with the risk inherent in its current business model. The Company’s discounted cash flow projections are based on its annual financial forecasts developed internally by management for use in managing its business. If the fair value of the reporting unit exceeds its carrying value, goodwill is not impaired and no further testing is required. If the fair value of the reporting unit is less than the carrying value, the Company must perform the second step of the impairment test to measurethen the amount of goodwill impairment loss. Inwill be the second step,amount by which the reporting unit'sunit’s carrying value exceeds its fair value, is allocatednot to all of the assets and liabilities of the reporting unit, including any unrecognized intangible assets, in a hypothetical analysis that calculates the implied fair value of goodwill in the same manner as if the reporting unit was being acquired by a market participant in a business combination. If the implied fair value of the reporting unit's goodwill is less thanexceed the carrying value, the difference is recorded as an impairment loss.amount of goodwill.
The Company performed its annual goodwill impairment analysis as of December 31, 20162019 and determined that there was no impairment of its goodwill. For the fair value ofyears ended December 31, 2018 and 2017, the reporting units withCompany did not recognize any goodwill exceeded their carrying values.impairment charges.
Intangible Assets
Intangible assets are comprised of existing technology, customer contracts and contractual relationships, and other definite-lived and indefinite-lived intangible assets. Identifiable intangible assets resulting from the acquisitions of entities accounted for using the purchase method of accounting are estimated by management based on the fair value of assets received. Identifiable definite-lived intangible assets are being amortized over the period of estimated benefit using the straight-line method and estimated useful lives ranging from 1six months to 10ten years.
Acquired indefinite-lived intangible assets related to the Company'sCompany’s in-process research and development ("(“IPR&D"&D”) are capitalized and subject to impairment testing until completion or abandonment of the projects. Upon successful completion of each project, the Company makes a separate determination of the useful life of the acquired indefinite-lived intangible assets and the related amortization is recorded as an expense over the estimated useful life of the specific projects. Indefinite-lived intangible assets are subject to at least an annual assessment for impairment, applying a fair-value based test. Under the income

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approach, the Company measures fair value of the indefinite-lived intangible assets based on a projected cash flow method using a discount rate determined by its management which is commensurate with the risk inherent in its current business model. The Company’s discounted cash flow projections are based on its annual financial forecasts developed internally by management for use in managing its business. If the fair value of the indefinite-lived intangible assets exceeds its carrying value, the indefinite-lived intangible assets are not impaired and no further testing is required. If the implied fair value of the indefinite-lived intangible assets is less than the carrying value, the difference is recorded as an impairment loss.
Inventories
Inventories are stated at the lower of cost or market.net realizable value. Cost is computed using standard cost, which approximates actual cost, on a first-in, first-out basis. Inventories are reduced for write downswrite-downs based on periodic reviews for evidence of slow-moving or obsolete parts. The write-down is based on comparison between inventory on hand and estimated future sales for each specific product. Once written down, inventory write downswrite-downs are not reversed until the inventory is sold or scrapped. Inventory write downswrite-downs are also established when conditions indicate that the net realizable value is less than cost due to physical deterioration, obsolescence, changes in price level or other causes.
Property, Plant and Equipment
Property, plant and equipment include computer equipment, computer software, machinery, leasehold improvements, furniture and fixtures and buildings. Computer equipment, computer software, machinery, and furniture and fixtures are stated at cost and generally depreciated on a straight-line basis over an estimated useful life of 3three years, 3three years to 5, 2five years, two years or 7,seven years, and 3three years,, respectively. The Company undertook a series of structural improvements to ready the Sunnyvale and Brecksville facilities for

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its use. The Company concluded that its requirement to fund construction costs and responsibility for cost overruns resulted in the Company being considered the owner of the buildings during the construction period for accounting purposes. Upon completion of construction, the Company concluded that it retained sufficient continuing involvement to preclude de-recognition of the buildings under the Financial Accounting Standards Board ("FASB") authoritative guidance applicable to sale leaseback for real estate. As such, the Company continues to account for the buildings as owned real estate and to record an imputed financing obligation for its obligation to the legal owners. The buildings will bewere depreciated on a straight-line basis over an estimated useful life of approximately 39 years. SeeRefer to Note 9,11, “Balance Sheet Details,” and Note 11,13, “Commitments and Contingencies,” for additional details. Leasehold improvements are amortized on a straight-line basis over the shorter of their estimated useful lives or the initial terms of the leases. Upon disposal, assets and related accumulated depreciation are removed from the accounts and the related gain or loss is included in the results from operations.
Definite-Lived and Indefinite-Lived Asset Impairment
The Company evaluates definite-lived and indefinite-lived assets (including property, plant and equipment and intangible assets) for impairment whenever events or changes in circumstances indicate the carrying value of an asset group may not be recoverable. The carrying value is not recoverable if it exceeds the undiscounted cash flows resulting from the use of the asset group and its eventual disposition. The Company’s estimates of future cash flows attributable to its asset groups require significant judgment based on its historical and anticipated results and are subject to many factors. Factors that the Company considers important which could trigger an impairment review include significant negative industry or economic trends, significant loss of clients, and significant changes in the manner of its use of the acquired assets or the strategy for its overall business.
When the Company determines that the carrying value of the asset groups may not be recoverable based upon the existence of one or more of the above indicators of impairment, the Company measures the potential impairment based on a projected discounted cash flow method using a discount rate determined by the Company to be commensurate with the risk inherent in the Company’s current business model. An impairment loss is recognized only if the carrying amount of the asset group is not recoverable and exceeds its fair value. The impairment charge is recorded to reduce the pre-impairment carrying amount of the assets based on the relative carrying amount of those assets, though not to reduce the carrying amount of an asset below its fair value. Different assumptions and judgments could materially affect the calculation of the fair value of the assets. During 20162019, the Company recognized an impairment of its IPR&D intangible asset of $18.3 million. See Note 5, "Intangible Assets2018 and Goodwill" for further details. During 2015,2017, the Company did not recognize any impairment of its definite-lived and indefinite-lived assets.
Income Taxes
Income taxes are accounted for using an asset and liability approach, which requires the recognition of deferred tax assets and liabilities for expected future tax events that have been recognized differently in Rambus'Rambus’ consolidated financial statements and tax returns. The measurement of current and deferred tax assets and liabilities is based on provisions of the enacted tax law and the effects of future changes in tax laws or rates are not anticipated. A valuation allowance is established when necessary to reduce deferred tax assets to amounts expected to be realized based on available evidence.

In addition, the calculation of the Company'sCompany’s tax liabilities involves dealing with uncertainties in the application of complex tax regulations. As a result, the Company reports a liability for unrecognized tax benefits resulting from uncertain tax positions taken or expected to be taken in its tax return. The Company considers many factors when evaluating and estimating its tax positions and tax benefits, which may require periodic adjustments and which may not accurately anticipate actual outcomes.

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Stock-Based Compensation and Equity Incentive Plans
The Company maintained stock plans covering a broad range of equity grants including stock options, nonvested equity stock and equity stock units and performance based instruments. In addition, the Company sponsors an Employee Stock Purchase Plan (“ESPP”), whereby eligible employees are entitled to purchase Common Stock semi-annually, by means of limited payroll deductions, at a 15% discount from the fair market value of the Common Stock as of specific dates.
The Company determines compensation expense associated with restricted stock units based on the fair value of its common stock on the date of grant. The Company determines compensation expense associated with stock options based on the estimated grant date fair value method using the Black-Scholes Merton valuation model. The Company generally recognizes compensation expense using a straight-line amortization method over the respective vesting period for awards that are ultimately expected to vest. Accordingly, stock-basedStock-based compensation expense for 2016, 20152019, 2018 and 20142017 has been reduced for estimated forfeitures. When estimating forfeitures, the Company considers voluntary termination behaviors as well as trends of

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actual option forfeitures. The Company will only recognize a tax benefit from stock-based awards in additional paid-in capital if an incremental tax benefit is realized after all other tax attributes currently available have been utilized. In addition, the Company has elected to account for the indirect effects of stock-based awards on other tax attributes, such as the research tax credits, through the consolidated statement of operations as part of the tax effect of stock-based compensation.

Cash and Cash Equivalents

Cash equivalents are highly liquid investments with original maturity of three months or less at the date of purchase. The Company maintains its cash balances with high quality financial institutions. Cash equivalents are invested in highly-rated and highly-liquid money market securities and certain U.S. government sponsored obligations.

Marketable Securities
Available-for-sale securities are carried at fair value, based on quoted market prices, with the unrealized gains or losses reported, net of tax, in stockholders’ equity as part of accumulated other comprehensive income (loss). The amortized cost of debt securities is adjusted for amortization of premiums and accretion of discounts to maturity, both of which are included in interest and other income, net. Realized gains and losses are recorded on the specific identification method and are included in interest and other income, net. The Company reviews its investments in marketable securities for possible other than temporary impairments on a regular basis. If any loss on investment is believed to be a credit loss, a charge will be recognized in operations. In evaluating whether a credit loss on a debt security has occurred, the Company considers the following factors: 1) the Company’s intent to sell the security, 2) if the Company intends to hold the security, whether or not it is more likely than not that the Company will be required to sell the security before recovery of the security’s amortized cost basis and 3) even if the Company intends to hold the security, whether or not the Company expects the security to recover the entire amortized cost basis. Due to the high credit quality and short term nature of the Company’s investments, there have been no material credit losses recorded to date. The classification of funds between short-term and long-term is based on whether the securities are available for use in operations or other purposes.
Fair Value of Financial Instruments
The carrying value of cash equivalents, accounts receivable and accounts payable approximate their fair values due to their relatively short maturities as of December 31, 20162019 and 20152018. Marketable securities are comprised of available-for-sale securities that are reported at fair value with the related unrealized gains and losses included in accumulated other comprehensive income (loss), a component of stockholders’ equity, net of tax. Fair value of the marketable securities is determined based on quoted market prices. The fair value of the Company'sCompany’s convertible notes fluctuates with interest rates and with the market price of the common stock, but does not affect the carrying value of the debt on the balance sheet.
Research and Development
Costs incurred in research and development, which include engineering expenses, such as salaries and related benefits, stock-based compensation, depreciation, professional services and overhead expenses related to the general development of Rambus’ products, are expensed as incurred. Software development costs are capitalized beginning when a product’s technological feasibility has been established and ending when a product is available for general release to customers. Rambus has not capitalized any software development costs since the period between establishing technological feasibility and general customer release is relatively short and as such, these costs have not been material.
Computation of Earnings (Loss) Per Share
Basic earnings (loss) per share is calculated by dividing the net income (loss) by the weighted average number of common shares outstanding during the period. Diluted earnings (loss) per share is calculated by dividing the earnings (loss) by the weighted average number of common shares and potentially dilutive securities outstanding during the period. Potentially

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dilutive common shares consist of incremental common shares issuable upon exercise of stock options, employee stock purchases, restricted stock and restricted stock units, and shares issuable upon the conversion of convertible notes. The dilutive effect of outstanding shares is reflected in diluted earnings per share by application of the treasury stock method. This method includes consideration of the amounts to be paid by the employees, the amount of excess tax benefits that would be recognized in equity if the instrument was exercised and the amount of unrecognized stock-based compensation related to future services. No potential dilutive common shares are included in the computation of any diluted per share amount when a net loss is reported.
Comprehensive Income (Loss)

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Comprehensive income (loss) is defined as the change in equity of a business enterprise during a period from transactions and other events and circumstances from non-owner sources, including foreign currency translation adjustments and unrealized gains and losses on marketable securities. Other comprehensive income (loss), net of tax, is presented in the consolidated statements of comprehensive income (loss).
Credit Concentration
As of December 31, 20162019 and 20152018, the Company’s cash, cash equivalents and marketable securities were invested with various financial institutions in the form of corporate notes, bonds and commercial paper, money market funds, U.S. Treasuries, U.S. Government Agencies, and municipal bonds and notes. The Company’s exposure to market risk for changes in interest rates relates primarily to its investment portfolio. The Company places its investments with high credit issuers and, by investment policy, attempts to limit the amount of credit exposure to any one issuer. As stated in the Company’s investment policy, it will ensure the safety and preservation of the Company’s invested funds by limiting default risk and market risk. The Company has no investments denominated in foreign country currencies and therefore is not subject to foreign exchange risk from these assets.
The Company mitigates default risk by investing in high credit quality securities and by positioning its portfolio to respond appropriately to a significant reduction in a credit rating of any investment issuer or guarantor. The portfolio includes only marketable securities with active secondary or resale markets to enable portfolio liquidity.
The Company’s note hedge transactions, entered into in connection with the 1.375% convertible senior notes due 2023 (the “2023 Notes”), expose the Company to credit risk to the extent that its counterparties may be unable to meet the terms of the transactions. The Company'sCompany mitigates this risk by limiting its counterparties to major financial institutions. Refer to Note 12, “Convertible Notes” for further details.
The Company’s accounts receivable are derived from revenue earned from customers located in the U.S. and internationally. SeeRefer to Note 6, "Segments7, “Segments and Major Customers"Customers” for further details.
Foreign Currency Translation and RemeasurementRe-Measurement
The Company translates the assets and liabilities of its non-U.S. dollar functional currency subsidiaries into U.S. dollars using exchange rates in effect at the end of each period. Revenue and expenses for these subsidiaries are translated using rates that approximate those in effect during the period. Gains and losses from these translations are recognized in foreign currency translation included in Accumulated Other Comprehensive Gain (Loss) in the consolidated statements of stockholders’ equity. The Company’s subsidiaries that use the U.S. dollar as their functional currency remeasurere-measure monetary assets and liabilities at exchange rates in effect at the end of each period, and inventories, property and nonmonetarynon-monetary assets and liabilities at historical rates. Additionally, foreign currency transaction gains and losses are included in interest income and other (income) expense, net, in the consolidated statements of operations and were not material in the periods presented. Subsequent to the divestiture of the Company’s Payments and Ticketing businesses, the U.S. dollar is primarily the functional currency of the Company’s foreign subsidiaries.
Business Combinations
The Company accounts for acquisitions of businessbusinesses using the purchase method of accounting, which requires the Company to recognize separately from goodwill the assets acquired and the liabilities assumed at their acquisition date fair values. While the Company uses its best estimates and assumptions to accurately value assets acquired and liabilities assumed at the acquisition date as well as contingent consideration, where applicable, the estimates are inherently uncertain and subject to refinement. As a result, during the measurement period, which may be up to one year from the acquisition date, the Company may record adjustments to the assets acquired and liabilities assumed with the corresponding offset to goodwill. Upon the

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conclusion of the measurement period or final determination of the values of assets acquired or liabilities assumed, whichever comes first, any subsequent adjustments are recorded to the consolidated statements of operations.
Accounting for business combinations requires management to make significant estimates and assumptions, especially at the acquisition date including the Company’s estimates for intangible assets, contractual obligations assumed and pre-acquisition contingencies where applicable. Although, the Company believes the assumptions and estimates made in the past have been reasonable and appropriate, they are based in part on historical experience and information obtained from the management of the acquired companies and are inherently uncertain. CriticalSignificant estimates and assumptions made by management in valuing certainestimating the fair value of the intangible assets the Company acquired include future expected cash flows from product sales, customer contracts and acquiredexisting technologies expected costs to develop IPR&D into commercially viable products and estimated cash flows from the projects when completedincluded revenue growth rates, operating expense margins, technology obsolescence rates and discount rates. Unanticipated events and circumstances may occur that may affect the accuracy or validity of such assumptions, estimates or actual results.
Litigation
Rambus may be involved in certain legal proceedings. Based upon consultation with outside counsel handling its defense in these matters and an analysis of potential results, if Rambus believes that a loss arising from such matters is probable and can be reasonably estimated, Rambus records the estimated liability in its consolidated financial statements. If only a range of

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estimated losses can be determined, Rambus records an amount within the range that, in its judgment, reflects the most likely outcome; if none of the estimates within that range is a better estimate than any other amount, Rambus records the low end of the range. Any such accrual would be charged to expense in the appropriate period. Rambus recognizes litigation expenses in the period in which the litigation services were provided.

3. Recent Accounting Pronouncements
Recent Accounting Pronouncements Adopted
In January 2017,February 2016, the Financial Accounting Standards Board ("FASB")(FASB) issued Accounting Standards Update ("ASU") No. 2017-04, "Intangibles—Goodwill and Other (Topic 350): Simplifying the Test for Goodwill Impairment," which removes Step 2 of the goodwill impairment test. A goodwill impairment will now be the amount by which a reporting unit’s carrying value exceeds its fair value, not to exceed the carrying amount of goodwill. This ASU is effective for interim and annual reporting periods beginning after December 15, 2019. Early adoption is permitted, including adoption in an interim period. The Company is currently evaluating the impact that this guidance will have on its consolidated financial statements.
In January 2017, the FASB issued ASU No. 2017-01, "Business Combinations (Topic 805): Clarifying the Definition of a Business." The amendment seeks to clarify the definition of a business with the objective of adding guidance to assist entities with evaluating whether transactions should be accounted for as acquisitions (or disposals) of assets or businesses. The definition of a business affects many areas of accounting including acquisitions, disposals, goodwill and consolidation. This ASU is effective for interim and annual reporting periods beginning after December 15, 2017, including interim periods within those periods. The amendments should be applied prospectively on or after the effective dates. The Company is currently evaluating the impact that this guidance will have on its consolidated financial statements.
In August 2016, the FASB issued ASU No. 2016-15 which amends the guidance on the classification of certain cash receipts and payments in the statement of cash flows. This ASU is effective for annual and interim reporting periods beginning after December 15, 2017 and is applied retrospectively. Early adoption is permitted including adoption in an interim period. The Company is currently evaluating the impact that this guidance will have on its financial condition and results of operations.
In June 2016, the FASB issued ASU No. 2016-13. The purpose of this ASU is to require a financial asset measured at amortized cost basis to be presented at the net amount expected to be collected. Credit losses relating to available-for-sale debt securities should be recorded through an allowance for credit losses. This ASU is effective for interim and annual reporting periods beginning after December 15, 2019. The Company is currently evaluating the impact that this guidance will have on its financial condition and results of operations.
In March 2016, the FASB issued ASU No. 2016-09, "Improvements to Employee Share-Based Payment Accounting." This ASU affects entities that issue share-based payment awards to their employees. The ASU is designed to simplify several aspects of accounting for share-based payment award transactions, which include the income tax consequences, classification of awards as either equity or liabilities, classification on the statement of cash flows and forfeiture rate calculations. The Company will adopt this ASU on its effective date of January 1, 2017. The adoption of this ASU is not expected to have a material impact on the Company's consolidated financial statements.
In February 2016, the FASB issued ASU(ASU) No. 2016-02, "Leases."“Leases.” This ASU requires lessees to recognize right-of-use assets and liabilities for operating leases, initially measured at the present value of the lease payments, on the balance sheet. In addition, it requires lessees to recognize a single lease cost, calculated so that the cost of the lease is allocated over the lease term, generally on a straight-line basis. This ASU will become effective for the Company in the first quarter of fiscal year 2019, and requires adoption using a modified retrospective approach. The Company is evaluating the impact of adopting this new accounting standard update on its consolidated financial statements and related disclosures and anticipates this new guidance will materially impact the Company’s financial statements given the Company has a significant number of operating leases.
In July 2015,2018, the FASB issued ASU No. 2015-11, "Simplifying2018-10,“Codification Improvements to Topic 842, Leases,” and ASU No. 2018-11, “Leases (Topic 842),” which allow the Measurementapplication of Inventory (Topic 330)," which applies to inventory that is measured using first-in, first-out (“FIFO”) or average cost. Under the updatednew guidance an entity should measure inventory that is within scope at the lowerbeginning of cost and net realizable value, which is the estimated selling pricesyear of adoption, recognizing a cumulative-effect adjustment to the opening balance of retained earnings in the ordinary courseperiod of business, less reasonably predictableadoption, in addition to the method of applying the new guidance retrospectively to each prior reporting period presented. The amendments in ASU No. 2018-10 and ASU No. 2018-11 have the same effective and transition requirements as ASU No. 2016-02 (collectively referred to as the “New Leasing Standard”).
The Company adopted the New Leasing Standard as of January 1, 2019 using the alternative transition method provided by ASU No. 2018-11 and did not recast comparative periods. The Company elected the package of practical expedients permitted under the transition guidance within the new standard, which among other things, allowed the Company to carry forward the historical lease classification. Additionally, the Company elected the practical expedient related to non-lease components in which the Company will not separate non-lease components from lease components. Finally, the Company made the policy election for the short-term leases exemptions, which allows the Company to not recognize lease assets and liabilities for leases having a term of 12 months or less. Upon adoption, the Company recognized $21.4 million and $23.9 million of lease assets and liabilities, respectively, on its consolidated balance sheet. The difference between the lease assets and lease liabilities, net of the deferred tax impact which was not material, was recorded as an adjustment to the opening accumulated deficit. Additionally, in accordance with the New Leasing Standard, the Company was required to derecognize the Sunnyvale and Ohio facilities as imputed facility obligations (as accounted for under the previous leasing guidance) and recognize these facilities as operating leases on the consolidated balance sheet. This change resulted in no longer recognizing interest expense associated with these imputed facility lease obligations, but instead, recognizing operating lease costs which will be included in operating costs and expenses on the consolidated statement of completion, disposaloperations. Furthermore, the Company derecognized $37.6 million of imputed financing obligation related to these facilities and transportation. Subsequent measurement is unchanged$32.0 million of capitalized building property upon adoption of the New Leasing Standard. The adoption of the New Leasing Standard resulted in a decrease to the Company’s opening accumulated deficit of $4.5 million.


Recent Accounting Pronouncements Not Yet Adopted
In January 2020, the FASB issued ASU No. 2020-01, “Investments—Equity Securities (Topic 321), Investments—Equity Method and Joint Ventures (Topic 323), and Derivatives and Hedging (Topic 815).” The amendments in this ASU clarify the interaction of the accounting for inventory that is measured using last-in, last-out (“LIFO”).equity securities under Topic 321 and investments accounted for under the equity method of accounting in Topic 323 and the accounting for certain forward contracts and purchased options accounted for under Topic 815. This ASU is effective for interim and annual and interimreporting periods beginning after December 15, 2016, and2020. Early adoption is permitted. The amendments in this ASU should be applied prospectively with earlyon a prospective basis. The Company is currently evaluating the impact that the adoption permitted atof this guidance will have on its consolidated financial statements.
In December 2019, the beginning of anFASB issued ASU No. 2019-12, “Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes.” The amendments in this ASU remove certain exceptions, and clarify and amend existing guidance. This ASU is effective for interim orand annual reporting period.periods beginning after December 15, 2020. Early adoption is permitted. Certain disclosures in ASU No. 2019-12 would need to be applied on a retrospective basis, modified retrospective basis, or prospective basis. The Company is currently evaluating the impact that the adoption of this guidance will have on its consolidated financial statements.
In August 2018, the FASB issued ASU No. 2018-13, “Fair Value Measurement (Topic 820): Disclosure Framework-Changes to the Disclosure Requirements for Fair Value Measurement.” The amendments in this ASU remove certain disclosures, modify certain disclosures and add additional disclosures. This ASU is effective for interim and annual reporting periods beginning after December 15, 2019. Early adoption is permitted. Certain disclosures in ASU No. 2018-13 would need to be applied on a retrospective basis and others on a prospective basis. The Company will adopt this ASU on its effective date of January 1, 2017. The adoption of this ASU is not expected to have a material impact on the Company's consolidated financial statements.
In April 2015, the FASB issued ASU No. 2015-03, "Simplifying the Presentation of Debt Issuance Costs," which requires debt issuance costs related to a recognized debt liability to be presented in the balance sheet as a direct deduction from the carrying amount of that debt liability, consistent with debt discounts. This ASU requires retrospective adoption2020 and is effective for financial statements issued for fiscal years beginning after December 15, 2015 and interim periods within those fiscal years.


Early adoption is permitted. The Company adopted this ASU in the first quarter of 2016 on a retrospective basis. Refer to Note 10, "Convertible Notes" for further details.
In May 2014, the FASB issued ASU No. 2014-09, Revenue from Contracts with Customers (Topic 606) which amended the existing accounting standards for revenue recognition. The core principle of the new guidance is for companies to recognize revenue to depict the transfer of goods or services to customers in amounts that reflect the consideration (that is, payment) to which the company expects to be entitled in exchange for those goods or services. The new guidance also will result in enhanced disclosures about revenue, provide guidance for transactions that were not previously addressed comprehensively (for example, service revenue and contract modifications) and improve guidance for multiple element arrangements. Subsequently, the FASB has issued the following standards related to ASU No. 2014-09: ASU No. 2016-10, Revenue from Contracts with Customers (Topic 606): Identifying Performance Obligations and Licensing; ASU No. 2016-12, Revenue from Contracts with Customers (Topic 606): Narrow-Scope Improvements and Practical Expedients; and ASU No. 2016-20, Technical Corrections and Improvements to Topic 606, Revenue from Contracts with Customers. The Company must adopt ASU 2016-10, ASU 2016-12 and ASU 2016-20 with ASU 2014-09 (collectively, the "new revenue standards").
The new revenue standards may be applied retrospectively to each prior period presented (full retrospective method) or retrospectively with the cumulative effect recognized as of the date of initial application (the modified retrospective method). The new revenue standards become effective for the Company on January 1, 2018. The Company currently anticipates adopting the new revenue standards using the full retrospective method. Whilewhile the Company is still incurrently evaluating the process of completing its analysis on the impact that this guidance will have on its consolidated financial statements, and related disclosures, the Company expectsdoes not expect the adoption of this guidance to have a material impact on its consolidated financial statements.
In June 2016, the FASB issued ASU No. 2016-13. The purpose of this ASU is to require a financial asset measured at amortized cost basis to be material.presented at the net amount expected to be collected. Credit losses relating to available-for-sale debt securities should be recorded through an allowance for credit losses. In April 2019, the FASB issued ASU No. 2019-04, “Codification Improvements to Topic 326, Financial Instruments-Credit Losses, Topic 815, Derivatives and Hedging, and Topic 825, Financial Instruments (ASU 2019-04),” which provided certain improvements to various ASUs, including ASU 2016-13. In May 2019, the FASB issued ASU No. 2019-05, “Financial Instruments-Credit Losses (Topic 326),” which provides an option to irrevocably elect the fair value option for certain financial assets previously measured at amortized cost basis. In November 2019, the FASB issued ASU No. 2019-10, “Financial Instruments-Credit Losses (Topic 326), Derivatives and Hedging (Topic 815), and Leases (Topic 842)” which amends certain effective dates. In November 2019, the FASB issued ASU No. 2019-11, “Financial Instruments-Credit Losses (Topic 326),” which provides additional clarifications. These ASUs and the related amendments are effective for interim and annual reporting periods beginning after December 15, 2019. The Company will adopt this ASU on January 1, 2020 and the Company does not expect the adoption of this guidance to have a material impact on its consolidated financial statements.

4. Revenue Recognition
Rambus’ revenue consists of royalty, product and contract and other revenue. Royalty revenue consists of patent and technology license royalties. Products consist of memory interface chips sold directly and indirectly to module manufacturers and OEMs worldwide through multiple channels, including our direct sales force and distributors. Contract and other revenue consists of software license fees, engineering fees associated with integration of Rambus’ technology solutions into its customers’ products and support and maintenance fees.
1.Royalty Revenue
Rambus’ patent and technology licensing arrangements generally range between 1 year and 7 years in duration and generally grant the licensee the right to use the Company’s entire IP portfolio as it evolves over time. These arrangements do not typically grant the licensee the right to terminate for convenience and where such rights exist, termination is prospective, with no refund of fees already paid by the licensee. There is no interdependency or interrelation between the IP included in the portfolio licensed upon contract inception and any IP subsequently made available to the licensee, and the Company would be able to fulfill its promises by transferring the portfolio and the additional IP use rights independently. However, the numbers of additions to, and removals from the portfolio (for example when a patent expires and renewal is not granted to the Company) in


any given period have historically been relatively consistent; as such, the Company does not allocate the transaction price between the rights granted at contract inception and those subsequently granted over time as a function of these additions.
Patent and technology licensing arrangements result in fixed payments received over time, with guaranteed minimum payments on occasion, variable payments calculated based on the licensee’s sale or use of the IP, or a mix of fixed and variable payments.
For fixed-fee arrangements (including arrangements that include minimum guaranteed amounts), variable royalty arrangements that the Company has concluded are fixed in substance, and the fixed portion of hybrid fixed/variable arrangements, the Company recognizes revenue upon control over the underlying IP use right transferring to the licensee, net of the effect of significant financing components calculated using customer-specific, risk-adjusted lending rates ranging between 3% and 6%, with the related interest income being recognized over time on an effective rate basis. Where a licensee has the contractual right to terminate a fixed-fee arrangement for convenience without any substantive penalty payable upon such termination, the Company applies the guidance in ASU No. 2014-09, Revenue from Contracts with Customers in Accounting Standards Codification (ASC) Topic 606 (“ASC 606” or “the New Revenue Standard”) to the duration of the contract in which the parties have present enforceable rights and obligations and only recognizes revenue for amounts that are due and payable.
For variable arrangements, the Company recognizes revenue based on an estimate of the licensee’s sale or usage of the IP during the period of reference, typically quarterly, with a true-up recorded when the Company receives the actual royalty report from the licensee.
2.Product Revenue
Product revenue is recognized upon shipment of product to customers, net of accruals for estimated sales returns and allowances, and to distributors, net of accruals for price protection and rights of return on products unsold by the distributors. To date, none of these accruals have been significant. The Company transacts with direct customers primarily pursuant to standard purchase orders for delivery of products and generally allows customers to cancel or change purchase orders within limited notice periods prior to the scheduled shipment date.
3.Contract and Other Revenue
Contract and other revenue consists of software license fees and engineering fees associated with integration of Rambus’ technology solutions into its customers’ related support and maintenance.
An initial software arrangement generally consists of a term-based or perpetual license, significant software customization services and support and maintenance services that include post-implementation customer support and the right to unspecified software updates and enhancements on a when and if available basis. The Company recognizes license and customization services revenue based on an over time model, measured using the input method. License and customization services revenue is reported as part of contract and other revenue which was approximately $28 million for the year ended December 31, 2019. Due to the nature of the work performed in these arrangements, the estimation of the over time model is complex and involves significant judgment. The key factor reviewed by management to estimate costs to complete each contract is the estimated man-months necessary to complete the project. The Company recognizes license renewal revenue at the beginning of the renewal period. The Company recognizes revenue from professional services purchased in addition to an initial software arrangement on a cumulative catch-up basis if these services are not distinct from the services provided as part of the initial software arrangement, or as a separate contract if these services are distinct.
Prior to the divestiture of the Company’s Payments and Ticketing businesses in 2019, the Company's Payment Product Group derived a significant portion of its revenue from heavily customized software in the mobile market, whereby the Payment Product Group’s software solution interacts with third-party solutions and other payment platforms to provide the functionality the customer requires. Historically, these third-party solutions have evolved at a rapid pace, with the Payment Product Group being required to deliver as part of its support and maintenance services the patches and updates needed to maintain the functionality of its own software offering. As the utility of the solution to the end customer erodes very quickly without these updates, these were viewed as critical and the customized software solution and updates were not separately identifiable. As such, these arrangements were treated as a single performance obligation; revenue was deferred until completion of the customization services, and recognized ratably over the committed support and maintenance term.
Prior to the divestiture of the Company’s Payments and Ticketing businesses in 2019, the Company's Ticketing Products Group primarily derived revenue from ticketing services arrangements that systematically consist of a software component,


support and maintenance, managed services and hosting services. The software could be hosted by third-party hosting service providers or the Company. All arrangements entered into subsequent to the acquisition (the Company had originally acquired the Payments and Ticketing businesses in 2016) preclude customers from taking possession of the software at any time during the hosting term and the Company had concluded that should a customer that was under contract as of the acquisition date ever request possession of the software, the Ticketing Products Group would have the ability to charge the customer, and enforce a claim to payment of a substantive fee in exchange for such right, and that the costs of setting up the environment needed to run the software would act as a significant disincentive to the customer taking possession of the software. Based on the above, the Company concluded that these services were a single performance obligation, with customers simultaneously receiving and consuming the benefits provided by the Ticketing Products Group’s performance, and recognized ticketing services revenue ratably over the term, commencing upon completion of setup activities. The Company recognized setup fees upon completion. While these activities did not transfer a service to the customer, the Company elected not to defer and amortized these fees over the expected duration of the customer relationship owing to the immateriality of the amounts charged.
Significant Judgments
Historically and with the exception noted below, no significant judgment has generally been required in determining the amount and timing of revenue from the Company’s contracts with customers.
The Company has adequate tools and controls in place, and substantial experience and expertise in timely and accurately tracking man-months incurred in completing customization and other professional services, and quantifying changes in estimates.
Key estimates used in recognizing revenue predominantly consist of the following:
All fixed-fee arrangements result in cash being received after control over the underlying IP use right has transferred to the licensee, and over a period exceeding a year. As such, all these arrangements include a significant financing component. The Company calculates a customer-specific lending rate using a Daily Treasury Yield Curve Rate that changes depending on the date on which the licensing arrangement was entered into and the term (in years) of the arrangement, and takes into consideration a licensee-specific risk profile determined based on a review of the licensee’s “Full Company View” Dun & Bradstreet report obtained on the date the licensing arrangement was signed by the parties, with a risk premium being added to the Daily Treasury Yield Curve Rate considering the overall business risk, financing strength and risk indicators, as listed.
The Company recognizes revenue on variable fee licensing arrangements on the basis of estimates. In connection with the adoption of the New Revenue Standard, the Company has set up specific procedures and controls to ensure timely and accurate quantification of variable royalties, and implemented new systems to enable the preparation of the estimates and reporting of the financial information required by the New Revenue Standard.
Contract Balances
Timing of revenue recognition may differ from the timing of invoicing to the Company’s customers. The Company records contract assets when revenue is recognized prior to invoicing, and a contract liability when revenue is recognized subsequent to invoicing.
The contract assets are primarily related to the Company’s fixed fee IP licensing arrangements and rights to consideration for performance obligations delivered but not billed as of December 31, 2019. The contract assets are transferred to receivables when the billing occurs.
The Company’s contract balances were as follows:
 As of
(In thousands)December 31, 2019 December 31, 2018
Unbilled receivables$528,069
 $673,616
Deferred revenue11,947
 19,566

During the years ended December 31, 2019 and December 31, 2018, the Company recognized $18.3 million and $20.5 million, respectively, of revenue that was included in the contract balances as of December 31, 2018 and January 1, 2018, respectively.


Revenue allocated to remaining performance obligations represents the transaction price allocated to the performance obligations that are unsatisfied, or partially unsatisfied, which includes unearned revenue and amounts that will be invoiced and recognized as revenue in future periods. Contracted but unsatisfied performance obligations were approximately $22.0 million as of December 31, 2019, which the Company primarily expects to recognize over the next 2 years.

5. Earnings (Loss) Per Share
The following table sets forth the computation of basic and diluted income (loss) per share:
For the Years Ended December 31,For the Years Ended December 31,
2016 2015 20142019 2018 2017
Net income per share:     
Net loss per share:     
Numerator:          
Net income$6,820
 $211,388
 $26,201
Net loss$(90,419) $(157,957) $(22,862)
Denominator:          
Weighted-average common shares outstanding - basic110,162
 114,814
 114,318
110,948
 108,450
 110,198
Effect of potential dilutive common shares2,978
 2,670
 3,306

 
 
Weighted-average common shares outstanding - diluted113,140
 117,484
 117,624
110,948
 108,450
 110,198
Basic net income per share$0.06
 $1.84
 $0.23
Diluted net income per share$0.06
 $1.80
 $0.22
Basic net loss per share$(0.81) $(1.46) $(0.21)
Diluted net loss per share$(0.81) $(1.46) $(0.21)
For the years ended December 31, 20162019, 20152018 and 20142017, options to purchase approximately 2.21.0 million,, 2.5 1.6 million and 5.61.5 million shares, respectively, were excluded from the calculation because they were anti-dilutive after considering proceeds from exercise, taxes and related unrecognized stock-based compensation expense.
For the years ended December 31, 2019, 2018 and 2017, an additional 2.4 million, 2.4 million and 3.7 million shares, respectively, have been excluded from the weighted average dilutive shares because there was a net loss for the periods. These shares do not include the Company’s 5% convertible senior notes due 2014 (the "2014 Notes")2023 Notes and the 1.125% convertible senior notes due 2018 (the "2018 Notes"“2018 Notes”). The par amount of convertible notes is payable in cash equal to the principal amount of the notes plus any accrued and unpaid interest and then the “in-the-money” conversion benefit feature at the conversion price above $19.31$18.93 and $12.07, respectively, per share is payable in cash, shares of the Company’s common stock or a combination of both. The Company has the option to pay cash, issue shares of common stock or any combination thereof for the aggregate amount due upon conversion of the notes. The Company’s intent is to settle the principal amount of the notes in cash upon conversion. As a result, upon conversion of the notes, only the amounts payable in excess of the principal amounts of the notes are considered in diluted earnings per share under the treasury stock method. Refer to Note 10, "Convertible12, “Convertible Notes” for more details.

5.6. Intangible Assets and Goodwill
In the fourth quarter of 2016 and 2015, the Company performed its annualGoodwill
The following tables present goodwill impairment analysisinformation for the MIDyears ended December 31, 2019 and RSD reporting units, which are the only reporting units with goodwill. The Company estimated the fair value of the reporting units using the income approach which was determined using Level 3 fair value inputs. The utilization of the income approach to determine fair value requires estimates of future operating results and cash flows discounted using an estimated discount rate. Cash flow projections are based on management's estimates of revenue growth rates and operating margins, taking into consideration industry and market conditions.December 31, 2018:

December 31,
2018
 Additions to Goodwill (1) Divestiture of Goodwill (2) Effect of Exchange Rates (3) December 31,
2019
          
 (In thousands)
Total goodwill$207,178
 $30,322
 $(54,494) $459
 $183,465

(1)In August 2019, the Company acquired Northwest Logic, Inc. (“Northwest Logic”), and in December 2019, the Company acquired the Secure Silicon IP and Protocols business from Verimatrix (the “Secure Silicon IP and Protocols business”), which resulted in the Company recognizing additional goodwill. Refer to Note 21, “Acquisitions,” for additional information.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (Continued)


(2)Refer to Note 17, “Divestiture,” for additional information.
(3)Effect of exchange rates relates to foreign currency translation adjustments for the period.
 As of December 31, 2019
 Gross Carrying Amount Accumulated Impairment Losses Net Carrying Amount
      
 (In thousands)
Total goodwill$205,235
 $(21,770) $183,465

As
 December 31,
2017
 Effect of Exchange Rates (1) December 31,
2018
      
 (In thousands)
Total goodwill$209,661
 $(2,483) $207,178

(1)Effect of exchange rates relates to foreign currency translation adjustments for the period.
 As of December 31, 2018
 Gross Carrying Amount Accumulated Impairment Losses Net Carrying Amount
      
 (In thousands)
Total goodwill$228,948
 $(21,770) $207,178

Intangible Assets
The components of the Company’s intangible assets as of December 31, 2016, the fair value of the MID reporting unit, with $66.6 million of goodwill, exceeded the carrying value of its net assets by approximately 299% and the fair value of the RSD reporting unit, with $138.2 million of goodwill, exceeded the carrying value of its net assets by approximately 89%. Key assumptions used to determine the fair value of the MID and RSD reporting units at December 31, 2016, were the revenue growth rates for the forecast period and terminal year, terminal growth rates and discount rates. Certain estimates used in the income approach involve information for new product lines with limited financial history and developing revenue models which increase the risk of differences between the projected and actual performance. The discount rate of 12% for MID and 16.5% for RSD is based on the reporting units’ overall risk profile relative to other guideline companies, market adoption of the Company's technology, the reporting units’ respective industry as well as the visibility of future expected cash flows. The terminal growth rate applied to determine fair value for both reporting units was 3%, which was based on historical experience as well as anticipated economic conditions, industry data and long term outlook for the business. These assumptions are inherently uncertain.
As of December 31, 2015, the fair value of the MID reporting unit, with $19.9 million of goodwill, exceeded the carrying value of its net assets by approximately 226% and the fair value of the RSD reporting unit, with $97.0 million of goodwill, exceeded the carrying value of its net assets by approximately 45%. Key assumptions used to determine the fair value of the MID and RSD reporting units at December 31, 2015, were the revenue growth rates for the forecast period and terminal year, terminal growth rates and discount rates. Certain estimates used in the income approach involve information for new product lines with limited financial history and developing revenue models which increase the risk of differences between the projected and actual performance. The discount rate of 13% for MID and 20% for RSD is based on the reporting units’ overall risk profile relative to other guideline companies, market adoption of the Company's technology, the reporting units’ respective industry as well as the visibility of future expected cash flows. The terminal growth rate applied to determine fair value for both reporting units was 3%, which was based on historical experience as well as anticipated economic conditions, industry data and long term outlook for the business. These assumptions are inherently uncertain.
It is reasonably possible that the businesses could perform significantly below the Company's expectations or a deterioration of market and economic conditions could occur. This would adversely impact the Company's ability to meet its projected results, which could cause the goodwill in any of its reporting units or intangible assets in any of its asset groups to become impaired. Significant differences between these estimates and actual cash flows could materially affect the Company's future financial results. If the reporting units are not successful in commercializing new business arrangements, if the businesses are unsuccessful in signing new license agreements or renewing its existing license agreements, or if the Company is unsuccessful in managing its costs, the revenue and income for these reporting units could adversely and materially deviate from their historical trends and could cause goodwill or intangible assets to become impaired. If the Company determines that its goodwill or intangible assets are impaired, it would be required to record a non-cash charge that could have a material adverse effect on its results of operations and financial position.
Goodwill
The following tables present goodwill information for each of the reportable segments for the years ended December 31, 20162019 and December 31, 2015:2018 were as follows:
Reportable Segment:December 31,
2015
 Addition to Goodwill (1) Impairment Charge of Goodwill Effect of Exchange Rates (2) December 31,
2016
 (In thousands)
MID$19,905
 $46,738
 $
 
 $66,643
RSD96,994
 46,903
 
 (5,746) 138,151
   Total$116,899
 $93,641
 $
 (5,746) $204,794
   As of December 31, 2019
 Useful Life Gross Carrying Amount (1) (2) 
Accumulated Amortization
(1) (2)
 Net Carrying Amount
        
   (In thousands)
Existing technology3 to 10 years $262,789
 $(213,354) $49,435
Customer contracts and contractual relationships0.5 to 10 years 36,293
 (33,428) 2,865
Non-compete agreements and trademarks3 years 300
 (300) 
IPR&DNot applicable 2,600
 
 2,600
Total intangible assets  $301,982
 $(247,082) $54,900
(1) The additions to goodwill are a result of the acquisitions of Smart Card Software Limited (“SCS”) during the first quarter of 2016, and Inphi's Memory Interconnect Business and the assets of the Snowbush IP group during the third quarter of 2016. See Note 19, “Acquisitions” for further details.

(2) Effect of exchange rates relates to foreign currency translation adjustments for the period.

(1)In October 2019, the Company disposed of approximately $20.7 million of net intangible assets in connection with the sale of the legal entities comprising the Company’s Payments and Ticketing businesses. Refer to Note 17, “Divestiture,” for additional information.
(2)In August 2019, the Company acquired Northwest Logic, and in December 2019, the Company acquired the Secure Silicon IP and Protocols business, which resulted in the Company recognizing additional intangible assets. Refer to Note 21, “Acquisitions,” for additional information.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (Continued)


   As of December 31, 2018
 Useful Life Gross Carrying Amount Accumulated Amortization Net Carrying Amount
        
   (In thousands)
Existing technology3 to 10 years $258,903
 $(213,824) $45,079
Customer contracts and contractual relationships1 to 10 years 67,667
 (54,410) 13,257
Non-compete agreements and trademarks3 years 300
 (300) 
IPR&DNot applicable 1,600
 
 1,600
Total intangible assets  $328,470
 $(268,534) $59,936
 As of December 31, 2016
Reportable Segment:Gross Carrying Amount Accumulated Impairment Losses Net Carrying Amount
 (In thousands)
MID$66,643
 $
 $66,643
RSD138,151
 
 138,151
Other21,770
 (21,770) 
   Total$226,564
 $(21,770) $204,794
Reportable Segment:December 31,
2014
 Addition to Goodwill Impairment Charge of Goodwill December 31,
2015
  
MID$19,905
 $
 $
 $19,905
RSD96,994
 
 
 96,994
   Total$116,899
 $
 $
 $116,899
 As of December 31, 2015
Reportable Segment:Gross Carrying Amount Accumulated Impairment Losses Net Carrying Amount
  
MID$19,905
 $
 $19,905
RSD96,994
 
 96,994
Other21,770
 (21,770) 
   Total$138,669
 $(21,770) $116,899
Intangible Assets
The components of the Company’s intangible assets as of December 31, 2016 and December 31, 2015 were as follows:
   As of December 31, 2016
 Useful Life Gross Carrying Amount Accumulated Amortization Net Carrying Amount
   (In thousands)
Existing technology (1)3 to 10 years $256,656
 $(156,577) $100,079
Customer contracts and contractual relationships (1)1 to 10 years 65,109
 (37,900) 27,209
Non-compete agreements and trademarks3 years 300
 (300) 
In-process research and development (2)Not applicable 5,100
 
 $5,100
   Total intangible assets  $327,165
 $(194,777) $132,388
(1) Includes intangible assets from the acquisitions of SCS, Inphi's Memory Interconnect Business, and the assets of the Snowbush IP group. See Note 19, “Acquisitions” for further details.
(2) Includes intangible assets from the acquisitions of Inphi's Memory Interconnect Business and the assets of the Snowbush IP group. See Note 19, “Acquisitions” for further details. The in-process research and development assets are accounted for as indefinite-lived intangible assets until the underlying projects are completed or abandoned.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (Continued)

   As of December 31, 2015
 Useful Life Gross Carrying Amount Accumulated Amortization Net Carrying Amount
   (In thousands)
Existing technology3 to 10 years $185,321
 $(127,028) $58,293
Customer contracts and contractual relationships1 to 10 years 31,093
 (25,120) 5,973
Non-compete agreements3 years 300
 (300) 
   Total intangible assets  $216,714
 $(152,448) $64,266

During the fourth quarter of 2016,year ended December 31, 2018, the Company recorded a charge of $18.3 millionacquired patents related to the impairment of some of the in-process research and development intangible asset of the original $21.8 million acquired in the acquisition of the assets of the Snowbush IP group. The impairment of this intangible asset resulted from a delay in the market served by this initiative. This delay will not impact the short-term revenue expectations but will impact the Company's revenue expectations several years into the future.
Included in customer contracts and contractual relationships are favorable contracts which are acquired software and service agreements where the Company has no performance obligations. Cash received from these acquired favorable contracts reduce the favorable contract intangible asset. During 2016 and 2015, the Company received $5.9 million and $0.1 million related to the favorable contracts, respectively. As of December 31, 2016 and 2015, the net balance of the favorable contract intangible assets was $3.6 million and zero, respectively. The estimated useful life is based on expected payment dates related to the favorable contracts.
The Company did not purchase any intangible assets in 2016 exceptits memory technology for those intangible assets acquired in the acquisitions during the year. See Note 19, “Acquisitions” for further details. The Company did not purchase any intangible assets in 2015 and 2014.an immaterial amount.
During the yearsyear ended December 31, 2016 and 2015,2018, the Company did not sell any intangible assets. During the year ended December 31, 2014, the Company sold portfolios of its intellectual property covering wireless and other technologies for $4.4 million and the related gain was recorded as gain from sale of intellectual property and revenue in the consolidated statements of operations.

Amortization expense for intangible assets for the years ended December 31, 20162019, 20152018, and 20142017 was $37.1$17.1 million, $25.129.3 million, and $26.6$42.0 million,, respectively. The estimated future amortization expense of intangible assets as of December 31, 20162019 was as follows (amounts in thousands):
Years Ending December 31:Amount
2020$18,413
202114,411
20227,444
20236,740
20245,292
Thereafter
Total amortizable purchased intangible assets52,300
IPR&D2,600
Total intangible assets$54,900

Years Ending December 31:Amount
2017$44,391
201828,880
201919,144
202018,505
202112,241
Thereafter9,227
 $132,388

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (Continued)

6.7. Segments and Major Customers
Operating segments are based upon Rambus'Rambus’ internal organization structure, the manner in which its operations are managed, the criteria used by its Chief Operating Decision Maker ("CODM"(“CODM”) to evaluate segment performance and availability of separate financial information regularly reviewed for resource allocation and performance assessment.
During 2016, theThe Company renamed its Cryptography Research Division organization to the Rambus Security Division ("RSD") and its Lighting and Display Technologies Division ("LDT") to the Rambus Lighting Division (“RLD”). The Companyhas determined its CODM to be the Chief Executive Officer (“CEO”). In line with the Company’s divestiture of its Payments and determinedTicketing businesses and its operating segments to be: (1) Memory and Interface Division ("MID"), which focuses the design, development, manufacturing through partnerships and licensing of technology and solutions that is related to memory and interfaces; (2) RSD, which focusesrefocus on the design, development and licensing of technologies for chip and system security, anti-counterfeiting, smart ticketing and mobile payments; (3) ESD, which encompasses our long-term research and development effortsits semiconductor operations, commencing in the areathird quarter of emerging technologies;2019, the CEO reviews financial information presented on a consolidated basis for purposes of managing the business, allocating resources, making operating decisions and (4) RLD, which focuses onassessing financial performance. On this basis, the design, developmentCompany is organized and licensingoperates as a single segment: high-speed interface IP and chips, and embedded security within the semiconductor space. As of technologies for lighting.
For the year ended December 31, 2016, MID2019, the Company has a single operating and RSD were considered reportable segments as they met the quantitative thresholdssegment. Accordingly, no additional disclosure of segment measures of profit or loss or total assets is applicable for disclosure as reportable segments. The results of the remaining operating segments are shown under “Other”.
all periods presented. The Company evaluateshas recast the performance of its segments based onprior-period segment operating income (loss), which is defined as revenue minusinformation to reflect the new segment operating expenses. Segment operating expenses are comprised of direct operating expenses.
Segment operating expenses do not include sales, general and administrative expenses and the allocation of certain expenses managed at the corporate level, such as stock-based compensation, amortization, and certain bonus and acquisition costs. The “Reconciling Items” category includes these unallocated sales, general and administrative expenses as well as corporate level expenses.
The tables below present reported segment operating income (loss) for the years ended December 31, 2016, 2015 and 2014:
 For the Year Ended December 31, 2016
 MID RSD Other Total
 (In thousands)
Revenues$239,843
 $76,175
 $20,579
 $336,597
Segment operating expenses68,460
 51,855
 30,397
 150,712
Segment operating income (loss)$171,383
 $24,320
 $(9,818) $185,885
Reconciling items 
    
 (152,243)
Operating income 
    
 $33,642
Interest and other income (expense), net 
    
 (11,005)
Income before income taxes 
    
 $22,637
 For the Year Ended December 31, 2015
 MID RSD Other Total
 (In thousands)
Revenues$221,968
 $50,497
 $23,813
 $296,278
Segment operating expense47,780
 29,056
 32,147
 108,983
Segment operating income (loss)$174,188
 $21,441
 $(8,334) $187,295
Reconciling items      (115,875)
Operating income    

 $71,420
Interest and other income (expense), net
   

 (11,189)
Income before income taxes 
    
 $60,231
structure.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (Continued)

 For the Year Ended December 31, 2014
 MID RSD Other Total
 (In thousands)
Revenues$226,303
 $49,330
 $20,925
 $296,558
Segment operating expenses40,816
 27,608
 34,106
 102,530
Segment operating income (loss)$185,487
 $21,722
 $(13,181) $194,028
Reconciling items

   

 (118,682)
Operating income
   

 $75,346
Interest and other income (expense), net 
    
 (25,096)
Income before income taxes      $50,250
The Company’s CODM does not review information regarding assets on an operating segment basis. Additionally, the Company does not record intersegment revenue or expense.
Accounts receivable from the Company'sCompany’s major customers representing 10% or more of total accounts receivable at December 31, 20162019 and December 31, 2015,2018, respectively, was as follows:
  As of December 31,
Customer  2016 2015
Customer 1 (MID reportable segment) 13% 16%
Customer 2 (Other segment) 12% 27%
Customer 3 (MID reportable segment) *
 28%
Customer 4 (RSD reportable segment) *
 21%
Customer 5 (RSD reportable segment) 17% *
 As of December 31,
 2019 2018
Customer 119% 39%
Customer 214% *
Customer 3*
 12%

*    Customer accounted for less than 10% of total accounts receivable in the period
Revenue from the Company’s major customers representing 10% or more of total revenue for the years ended December 31, 20162019, 20152018 and 20142017 were as follows:
 Years Ended December 31,
 2019 2018 2017
Customer A*
 *
 17%
Customer B10% *
 13%
Customer C*
 *
 13%
Customer D14% 15% *
Customer E*
 11% *

 Years Ended December 31,
 2016 2015 2014
Customer A (MID and RSD reportable segments)19% 20% 20%
Customer B (MID reportable segment)20% 19% 16%
Customer C (MID reportable segment)13% 13% 13%

* Customer accounted for less than 10% of total revenue in the period
Revenue from customers in the geographic regions based on the location of contracting parties is as follows:
Years Ended December 31,Years Ended December 31,
2016 2015 20142019 2018 2017
(In thousands)(In thousands)
USA$134,526
 $129,567
 $165,263
Taiwan24,118
 21,749
 9,953
South Korea$129,542
 $115,486
 $107,441
3,583
 13,421
 115,811
USA121,209
 118,278
 109,060
Japan30,215
 29,687
 30,454
11,877
 23,222
 23,378
Europe16,031
 9,616
 21,349
10,262
 15,668
 22,597
Canada3,478
 214
 7,119
3,554
 4,960
 4,373
Singapore17,908
 16,312
 12,980
21,751
 19,140
 22,554
Asia-Other18,214
 6,685
 8,155
14,356
 3,474
 29,167
Total$336,597
 $296,278
 $296,558
$224,027
 $231,201
 $393,096


NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (Continued)

At December 31, 20162019, of the $58.4$44.7 million of total property, plant and equipment, approximately $55.0$40.3 million were located in the United States, $1.3$3.4 million were located in India and $2.1$1.0 million were located in other foreign locations. At December 31, 20152018, of the $56.6$57.0 million of total property, plant and equipment, approximately $55.2$50.4 million were located in the United States, $1.3$3.8 million were located in India and $0.1$2.8 million were located in other foreign locations.

7.8. Marketable Securities
Rambus invests its excess cash and cash equivalents primarily in U.S. government-sponsored obligations, commercial paper, corporate notes and bonds, money market funds and municipal notes and bonds that mature within three years. As of December 31, 20162019 and 20152018, all of the Company’s cash equivalents and marketable securities have a remaining maturity of less than one year.
All cash equivalents and marketable securities are classified as available-for-sale. Total cash, cash equivalents and marketable securities are summarized as follows:

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (Continued)
 As of December 31, 2016
(Dollars in thousands)Fair Value Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Weighted Rate of Return
Money market funds$10,681
 $10,681
 $
 $
 0.41%
U.S. Government bonds and notes48,292
 48,291
 1
 
 0.39%
Corporate notes, bonds, commercial paper and other62,178
 62,199
 
 (21)
 0.66%
Total cash equivalents and marketable securities121,151
 121,171
 1
 (21)
  
Cash51,031
 51,031
 
 
  
Total cash, cash equivalents and marketable securities$172,182
 $172,202
 $1
 $(21)  

As of December 31, 2015As of December 31, 2019
(Dollars in thousands)Fair Value Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Weighted Rate of ReturnFair Value Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Weighted Rate of Return
Money market funds$77,804
 $77,804
 $
 $
 0.12%$10,065
 $10,065
 $
 $
 1.48%
U.S. Government bonds and notes14,110
 14,142
 
 (32) 0.48%39,086
 39,087
 
 (1) 1.49%
Corporate notes, bonds, commercial paper and other160,823
 160,979
 
 (156) 0.45%314,391
 314,435
 19
 (63) 1.81%
Total cash equivalents and marketable securities252,737
 252,925
 
 (188)  363,542
 363,587
 19
 (64)  
Cash34,969
 34,969
 
 
  44,122
 44,122
 
 
  
Total cash, cash equivalents and marketable securities$287,706
 $287,894
 $
 $(188)  $407,664
 $407,709
 $19
 $(64)  
 As of December 31, 2018
(Dollars in thousands)Fair Value Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Weighted Rate of Return
Money market funds$10,080
 $10,080
 $
 $
 2.23%
U.S. Government bonds and notes32,630
 32,634
 
 (4) 2.28%
Corporate notes, bonds, commercial paper and other183,998
 184,095
 
 (97) 2.37%
Total cash equivalents and marketable securities226,708
 226,809
 
 (101)  
Cash51,056
 51,056
 
 
  
Total cash, cash equivalents and marketable securities$277,764
 $277,865
 $
 $(101)  

Available-for-sale securities are reported at fair value on the balance sheets and classified as follows:
 As of
 December 31,
2019
 December 31,
2018
 (Dollars in thousands)
Cash equivalents$58,054
 $64,868
Short term marketable securities305,488
 161,840
Total cash equivalents and marketable securities363,542
 226,708
Cash44,122
 51,056
Total cash, cash equivalents and marketable securities$407,664
 $277,764

 As of
 December 31,
2016
 December 31,
2015
 (Dollars in thousands)
Cash equivalents$84,263
 $108,795
Short term marketable securities36,888
 143,942
Total cash equivalents and marketable securities121,151
 252,737
Cash51,031
 34,969
Total cash, cash equivalents and marketable securities$172,182
 $287,706
The Company continues to invest in highly rated quality, highly liquid debt securities. As of December 31, 2016,2019, these securities have a remaining maturity of less than one year. The Company holds all of its marketable securities as available-for-sale, marks them to market, and regularly reviews its portfolio to ensure adherence to its investment policy and to monitor individual investments for risk analysis, proper valuation, and unrealized losses that may be other than temporary.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (Continued)

The estimated fair value of cash equivalents and marketable securities classified by the length of time that the securities have been in a continuous unrealized loss position at December 31, 20162019 and 20152018 are as follows:
 Fair Value Gross Unrealized Loss
 December 31,
2019
 December 31,
2018
 December 31,
2019
 December 31,
2018
        
 (In thousands)
Less than one year       
U.S. Government bonds and notes$14,112
 $32,630
 $(1) $(4)
Corporate notes, bonds and commercial paper250,822
 183,998
 (63) (97)
Total Corporate notes, bonds, and commercial paper and U.S. Government bonds and notes$264,934
 $216,628
 $(64) $(101)

 Fair Value Gross Unrealized Loss
 December 31,
2016
 December 31,
2015
 December 31,
2016
 December 31,
2015
 (In thousands)
Less than one year       
U.S. Government bonds and notes$18,395
 $14,110
 $
 $(32)
Corporate notes, bonds and commercial paper54,377
 145,563
 (21) (156)
Total Corporate notes, bonds, and commercial paper and U.S. Government bonds and notes$72,772
 $159,673
 $(21) $(188)
The gross unrealized loss at December 31, 20162019 and 20152018 was not material in relation to the Company’s total available-for-sale portfolio. The gross unrealized loss can be primarily attributed to a combination of market conditions as well as the

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (Continued)

demand for and duration of the U.S. government-sponsored obligations and corporate notes and bonds. The Company has no intent to sell, there is no requirement to sell and the Company believes that it can recover the amortized cost of these investments. The Company has found no evidence of impairment due to credit losses in its portfolio. Therefore, these unrealized losses were recorded in other comprehensive income (loss). However, the Company cannot provide any assurance that its portfolio of cash, cash equivalents and marketable securities will not be impacted by adverse conditions in the financial markets, which may require the Company in the future to record an impairment charge for credit losses which could adversely impact its financial results.
SeeRefer to Note 8,9, “Fair Value of Financial Instruments,” for discussion regarding the fair value of the Company’s cash equivalents and marketable securities.
8.9. Fair Value of Financial Instruments
The fair value measurement statement defines fair value as the price that would be received from selling an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. When determining fair value, the Company considers the principal or most advantageous market in which the Company would transact, and the Company considers assumptions that market participants would use when pricing the asset or liability, such as inherent risk, transfer restrictions, and risk of non-performance.
The Company’s financial instruments are measured and recorded at fair value, except for costequity method investments and convertible notes. The Company’s non-financial assets, such as goodwill, intangible assets, and property, plant and equipment, are measured at fair value when there is an indicator of impairment and recorded at fair value only when an impairment charge is recognized. The Company’s equity method investments are initially recognized at cost, and the carrying amount is increased or decreased to recognize the Company’s share of the profit or loss of the investee after the date of acquisition. The Company’s share of the investee’s profit or loss is recognized in the Company’s consolidated statements of operations. Distributions received from an investee reduce the carrying amount of the investment.
Fair Value Hierarchy
The fair value measurement statement requires disclosure that establishes a framework for measuring fair value and expands disclosure about fair value measurements. The statement requires fair value measurement be classified and disclosed in one of the following three categories:
Level 1: Unadjusted quoted prices in active markets that are accessible at the measurement date for identical, unrestricted assets or liabilities.
The Company uses unadjusted quotes to determine fair value. The financial assets in Level 1 include money market funds.
Level 2: Quoted prices in markets that are not active, or inputs which are observable, either directly or indirectly, for substantially the full term of the asset or liability.
The Company uses observable pricing inputs including benchmark yields, reported trades, and broker/dealer quotes. The financial assets in Level 2 include U.S. government bonds and notes, corporate notes, commercial paper and municipal bonds and notes.
Level 3: Prices or valuation techniques that require inputs that are both significant to the fair value measurement and unobservable (i.e., supported by little or no market activity).

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (Continued)

The Company does not have any financial assets in Level 3 previously included a cost investment whose value is determined using inputs that are both unobservableas of December 31, 2019 and significant to the fair value measurements, as discussed below.2018.
The Company reviews the pricing inputs by obtaining prices from a different source for the same security on a sample of its portfolio. The Company has not adjusted the pricing inputs it has obtained. The following table presents the financial instruments that are carried at fair value and summarizes the valuation of its cash equivalents and marketable securities by the above pricing levels as of December 31, 20162019 and 20152018:

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (Continued)

As of December 31, 2019
As of December 31, 2016Total 
Quoted Market Prices in Active Markets
(Level 1)
 
Significant Other Observable Inputs
(Level 2)
 
Significant Unobservable Inputs
(Level 3)
Total Quoted Market Prices in Active Markets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3)       
(In thousands)(In thousands)
Money market funds$10,681
 $10,681
 $
 $
$10,065
 $10,065
 $
 $
U.S. Government bonds and notes48,292
 
 48,292
 
39,086
 
 39,086
 
Corporate notes, bonds, commercial paper and other62,178
 303
 61,875
 
314,391
 
 314,391
 
Total available-for-sale securities$121,151
 $10,984
 $110,167
 $
$363,542
 $10,065
 $353,477
 $
 As of December 31, 2018
 Total 
Quoted Market Prices in Active Markets
(Level 1)
 
Significant Other Observable Inputs
(Level 2)
 
Significant Unobservable Inputs
(Level 3)
        
 (In thousands)
Money market funds$10,080
 $10,080
 $
 $
U.S. Government bonds and notes32,630
 
 32,630
 
Corporate notes, bonds, commercial paper and other183,998
 
 183,998
 
Total available-for-sale securities$226,708
 $10,080
 $216,628
 $
 As of December 31, 2015
 Total Quoted Market Prices in Active Markets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3)
 (In thousands)
Money market funds$77,804
 $77,804
 $
 $
U.S. Government bonds and notes14,110
 
 14,110
 
Corporate notes, bonds, commercial paper and other160,823
 1,264
 159,559
 
Total available-for-sale securities$252,737
 $79,068
 $173,669
 $

The Company monitors its investments for other-than-temporary impairment and records appropriate reductions in carrying value when necessary. The Company monitors its investments for other-than-temporary losses by considering current factors, including the economic environment, market conditions, operational performance and other specific factors relating to the business underlying the investment, reductions in carrying values when necessary and the Company’s ability and intent to hold the investment for a period of time which may be sufficient for anticipated recovery in the market. Any other-than-temporary loss is reported under “Interest and other income (expense), net” in the consolidated statement of operations. During the years ended December 31, 20162019 and 2015,2018, the Company recorded no other-than-temporary impairment charges on its investments. For
During the year ended December 31, 2014,second half of 2018, the Company recorded impairment charges related to its non-marketable equity security of a private company as described below.
The Company made an investment of $2.0 million in a non-marketable equity security of a private company during 2009. Prior tocompany. This equity investment is accounted for under the second quarterequity method of 2013,accounting, and the Company had not recorded any impairment charges related to this investment as there had been no events that causedaccounts for its equity method share of the income (loss) on a decrease in its fair value below the carrying cost. During the year endedquarterly basis. As of December 31, 2014, as part2019, the Company’s 25.0% ownership percentage amounted to a $3.6 million equity interest in this equity investment. As of its periodic evaluation ofDecember 31, 2018, the fair value of the investmentCompany’s 27.7% ownership percentage amounted to a $3.3 million equity interest in the non-marketablethis equity security, and basedinvestment. The Company’s equity interest was included in other assets on the information provided by the private company at that time, the Company determined that there was a decrease in the security's fair value.accompanying consolidated balance sheets. The fair value of the non-marketable equity security was determined based on an income approach, using level 3 fair value inputs, as it was deemed to be the most indicative of the security's fair value. Accordingly, the Company recorded impairment charges of $0.6 million within interest income and other income (expense), net,immaterial amounts in theits consolidated statements of operations during 2014.representing its share of the investee’s loss for the years ended December 31, 2019 and 2018.
In October 2015, the previously written down private company's stock became publicly traded and as a result, the investment in this equity security was classified as an available-for-sale security and was re-measured to fair value, resulting in a $1.3 million increase in marketable securities and accumulated other comprehensive income at the time of re-measurement.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (Continued)

During the years ended December 31, 20162019 and 20152018, there were no transfers of financial instruments between different categories of fair value.
The following table presents the financial instruments that are not carried at fair value but which require fair value disclosure as of December 31, 20162019 and 20152018:
 As of December 31, 2019 As of December 31, 2018

(in thousands)
Face
Value
 Carrying Value 
Fair
Value
 
Face
Value
 Carrying Value 
Fair
Value
1.375% Convertible Senior Notes due 2023$172,500
 $148,788
 $174,239
 $172,500
 $141,934
 $150,075

 As of December 31, 2016 As of December 31, 2015

(in thousands)
Face
Value
 Carrying Value 
Fair
Value
 
Face
Value
 Carrying Value 
Fair
Value
1.125% Convertible Senior Notes due 2018138,000
 126,167
 173,961
 138,000
 119,418
 156,292
The fair value of the convertible notes at each balance sheet date is determined based on recent quoted market prices for these notes which is a level 2 measurement. As discussed in Note 10,12, “Convertible Notes,” as of December 31, 20162019, the convertible notes are carried at their face value of $138.0$172.5 million, less any unamortized debt discount and unamortized debt

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (Continued)

issuance costs. The carrying value of other financial instruments, including accounts receivable, accounts payable and other payables,liabilities, approximates fair value due to their short maturities.
Information regarding the Company'sCompany’s goodwill and long-lived assets balances are disclosed in Note 5, "Intangible6, “Intangible Assets and Goodwill".Goodwill.”
9.10. Leases
On July 8, 2019, the Company entered into a definitive triple net space lease agreement with 237 North First Street Holdings, LLC (the “Landlord”), whereby the Company will lease approximately 90,000 square feet of office space located at 4453 North First Street in San Jose, California (the “Lease”). The office space will serve as the Company’s corporate headquarters and include engineering, marketing and administrative functions. The Company expects to move to the new premises during the summer of 2020. The Lease has a term of 128 months from the commencement date in October 2019. The starting rent of the Lease is approximately $3.26 per square foot on a triple net basis. The annual base rent increases each year to certain fixed amounts over the course of the term as set forth in the Lease and will be $4.38 per square foot in the eleventh year. In addition to the base rent, the Company will also pay operating expenses, insurance expenses, real estate taxes, and a management fee. The Lease also allows for an option to expand, wherein the Company has the right of first refusal to rent additional space in the building. The Company has a one-time option to extend the Lease for a period of 60 months and may elect to terminate the Lease, via written notice to the Landlord, in the event the office space is damaged or destroyed. Total future required payments under the Lease are approximately $41 million. Pursuant to the terms of the lease, the landlord agreed to reimburse the Company up to $8.9 million, related to a tenant improvement allowance. The lease of the Company’s current Sunnyvale, California headquarters expires on June 30, 2020.
Refer to Note 13, “Commitments and Contingencies,” for additional information regarding the Company’s leases.
The Company used its incremental borrowing rate to measure the lease liabilities at the adoption date for its existing operating leases that commenced prior to January 1, 2019 which was based on the remaining lease term and remaining lease payments for such leases. On an ongoing basis, as most of the Company’s leases do not provide an implicit rate, the Company will use its incremental borrowing rate based on the information available at commencement date in determining the present value of lease payments. The Company will use the implicit rate when readily determinable. Refer to Note 3, “Recent Accounting Pronouncements” for additional information regarding the adoption of the New Leasing Standard on January 1, 2019.
The table below reconciles the undiscounted cash flows for the first five years and total of the remaining years to the operating lease liabilities recorded on the consolidated balance sheet as of December 31, 2019 (in thousands):
Years ending December 31,Amount
2020$7,926
20218,602
20227,381
20234,618
20243,977
Thereafter23,314
Total minimum lease payments55,818
Less: amount of lease payments representing interest(9,572)
Present value of future minimum lease payments46,246
Less: current obligations under leases(6,357)
Long-term lease obligations$39,889

As of December 31, 2019, the weighted-average remaining lease term for the Company’s operating leases was 7.9 years, and the weighted-average discount rate used to determine the present value of the Company’s operating leases was 4.2%.
Operating lease costs included in research and development and selling, general and administrative costs on the statement of operations were $9.6 million for the year ended December 31, 2019. Rent expense, recorded under accounting guidance in

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (Continued)

effect prior to January 1, 2019 when the New Leasing Standard became effective for the Company, was approximately $5.2 million and $4.4 million for the years ended December 31, 2018 and 2017, respectively.
Cash paid for amounts included in the measurement of operating lease liabilities was $10.4 million for the year ended December 31, 2019.

11. Balance Sheet Details
Inventories
Inventories consist of the following:
 As of December 31,
 2019 2018
 (In thousands)
Raw materials$3,997
 $2,583
Work in process1,455
 145
Finished goods4,634
 4,044
Total$10,086
 $6,772
 As of December 31,
 2016 2015
 (In thousands)
Raw materials3,773
 597
Work in process616
 74
Finished goods1,244
 409
 $5,633
 $1,080

Property, Plant and Equipment, net
Property, plant and equipment, net is comprised of the following:
 As of December 31,
 2019 2018
 (In thousands)
Building (1)$
 $40,320
Computer software50,453
 26,127
Computer equipment36,761
 37,223
Furniture and fixtures16,136
 16,286
Leasehold improvements10,316
 10,824
Machinery10,446
 9,097
Construction in progress1,691
 429
Property, plant and equipment, gross125,803
 140,306
Less accumulated depreciation and amortization(81,089) (83,278)
Property, plant and equipment, net$44,714
 $57,028

 As of December 31,
 2016 2015
 (In thousands)
Building$40,320
 $40,320
Computer software20,922
 20,012
Computer equipment36,608
 31,224
Furniture and fixtures15,140
 13,943
Leasehold improvements7,176
 7,098
Machinery17,406
 11,037
Construction in progress1,075
 637
 138,647
 124,271
Less accumulated depreciation and amortization(80,205) (67,655)
 $58,442
 $56,616
As

(1)Refer to Note 3, “Recent Accounting Pronouncements” and Note 13, “Commitments and Contingencies,” for a discussion related to the Company’s facility leases due to the adoption of the New Leasing Standard on January 1, 2019.
Depreciation expense for the years ended December 31, 20162019, 2018 and 2015, for the Sunnyvale2017 was $15.2 million, $10.7 million and Brecksville facilities, the Company had capitalized $40.3$13.3 million in building based on the estimated fair value of the portion of the unfinished spaces, capitalized interest on the unfinished, respectively.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (Continued)

spaces and construction costs related to the build-out of the facilities. See Note 11, "Commitments and Contingencies" for additional details.
Depreciation expense for the years ended December 31, 2016, 2015 and 2014 was $13.0 million, $12.4 million and $13.6 million, respectively.
Accumulated Other Comprehensive Gain (Loss)
Accumulated other comprehensive gain (loss) is comprised of the following:
 As of December 31,
 2019 2018
 (In thousands)
Foreign currency translation adjustments$105
 $(10,040)
Unrealized loss on available-for-sale securities, net of tax(197) (251)
Total$(92) $(10,291)
 As of December 31,
 2016 2015
 (In thousands)
Foreign currency translation adjustments$(13,392) $95
Unrealized gain (loss) on available-for-sale securities, net of tax(116) 278
Total$(13,508) $373



10.12. Convertible Notes
The Company adopted ASU 2015-03 during the first quarter of 2016. Pursuant to the guidance in ASU 2015-03, the Company has reclassified unamortized debt issuance costs associated with the Company's 2018 Notes in the previously reported Consolidated Balance Sheet as of December 31, 2015, as follows:
(In thousands) As presented December 31, 2015 Reclassifications As adjusted December 31, 2015
Other assets $3,648
 $(1,483) $2,165
Convertible notes, long-term $120,901
 $(1,483) $119,418

The Company’s convertible notes are shown in the following table.table:
(Dollars in thousands)As of December 31, 2019 As of December 31, 2018
1.375% Convertible Senior Notes due 2023$172,500
 $172,500
Unamortized discount - 2023 Notes(22,163) (28,517)
Unamortized debt issuance costs - 2023 Notes(1,549) (2,049)
Total convertible notes$148,788
 $141,934
Less current portion
 
Total long-term convertible notes$148,788
 $141,934

1.375% Convertible Senior Notes due 2023.On November 17, 2017, the Company issued $172.5 million aggregate principal amount of 1.375% convertible senior notes pursuant to an indenture (the “2023 Indenture”), by and between the Company and U.S. Bank National Association, as trustee (the “Trustee”). In accounting for the 2023 Notes at issuance, the Company separated the 2023 Notes into liability and equity components pursuant to the accounting standards for convertible debt instruments that may be fully or partially settled in cash upon conversion. As of the date of issuance, the Company determined that the liability component of the 2023 Notes was $137.3 million and the equity component of the 2023 Notes was $35.2 million. The fair value of the liability component was estimated using an interest rate for a similar instrument without a conversion feature. The unamortized discount related to the 2023 Notes is being amortized to interest expense using the effective interest method over approximately five years.
The 2023 Notes bear interest at a rate of 1.375% per year, payable semi-annually on February 1 and August 1 of each year, beginning on August 1, 2018. The 2023 Notes will mature on February 1, 2023, unless earlier repurchased by the Company or converted pursuant to their terms.
The Company incurred transaction costs of approximately $3.3 million related to the issuance of 2023 Notes. In accounting for these costs, the Company allocated the costs to the liability and equity components in proportion to the allocation of proceeds from the issuance of the 2023 Notes to such components. Transaction costs allocated to the liability component of $2.6 million are netted against the carrying amount of the liability in the consolidated balance sheet and are amortized to interest expense using the effective interest method over the term of the 2023 Notes. The transaction costs allocated to the equity component of $0.7 million were recorded as additional paid-in capital.
The initial conversion rate of the 2023 Notes is 52.8318 shares of the Company’s common stock per $1,000 principal amount of 2023 Notes (which is equivalent to an initial conversion price of approximately $18.93 per share). The conversion rate will be subject to adjustment upon the occurrence of certain specified events but will not be adjusted for accrued and unpaid interest. In addition, upon the occurrence of a make-whole fundamental change (as defined in the 2023 Indenture), the Company will, in certain circumstances, increase the conversion rate by a number of additional shares for a holder that elects to convert its 2023 Notes in connection with such make-whole fundamental change.
Prior to the close of business on the business day immediately preceding November 1, 2022, the 2023 Notes will be convertible only under the following circumstances: (1) during any calendar quarter commencing after March 31, 2018, and only during such calendar quarter, if the last reported sale price of the common stock for at least 20 trading days (whether or not consecutive) in a period of 30 consecutive trading days ending on the last trading day of the immediately preceding calendar quarter is more than 130% of the conversion price on each applicable trading day; (2) during the five business day period after

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (Continued)
(Dollars in thousands)As of December 31, 2016 As of December 31, 2015
1.125% Convertible Senior Notes due 2018$138,000
 $138,000
Unamortized discount(10,913) (17,099)
Unamortized debt issuance costs(920) (1,483)
Total convertible notes$126,167
 $119,418
Less current portion
 
Total long-term convertible notes$126,167
 $119,418

any five consecutive trading day period in which, for each trading day of that period, the trading price per $1,000 principal amount of 2023 Notes for such trading day was less than 98% of the product of the last reported sale price of the common stock and the conversion rate on each such trading day; (3) upon the occurrence of specified distributions to holders of our common stock; or (4) upon the occurrence of specified corporate transactions. On or after November 1, 2022, until the close of business on the second scheduled trading day immediately preceding the maturity date, holders of the 2023 Notes may convert all or a portion of their 2023 Notes regardless of the foregoing conditions. Upon conversion, the Company will pay cash up to the aggregate principal amount of the 2023 Notes to be converted and pay or deliver, as the case may be, cash, shares of common stock or a combination of cash and shares of common stock, at the Company’s election, in respect of the remainder, if any, of its conversion obligation in excess of the aggregate principal amount of the 2023 Notes being converted.
The Company may not redeem the 2023 Notes prior to the maturity date and no sinking fund is provided for the 2023 Notes. Upon the occurrence of a fundamental change (as defined in the 2023 Indenture) prior to the maturity date, holders may require the Company to repurchase all or a portion of the 2023 Notes for cash at a price equal to 100% of the principal amount of the 2023 Notes to be repurchased, plus any accrued and unpaid interest to, but excluding, the fundamental change repurchase date.
The 2023 Notes are the Company’s senior unsecured obligations and will rank senior in right of payment to any of the Company’s indebtedness that is expressly subordinated in right of payment to the notes; equal in right of payment with the Company’s existing and future liabilities that are not so subordinated, including its “2018 Notes”; effectively junior in right of payment to any of the Company’s secured indebtedness to the extent of the value of the assets securing such indebtedness; and structurally junior to any existing and future indebtedness and other liabilities (including trade payables, but excluding intercompany obligations and liabilities) and any preferred stock of subsidiaries of the Company.
The following events are considered “events of default” with respect to the 2023 Notes, which may result in the acceleration of the maturity of the 2023 Notes:
(1) the Company defaults in the payment when due of any principal of any of the 2023 Notes at maturity or upon exercise of a repurchase right or otherwise;
(2) the Company defaults in the payment of any interest, including additional interest, if any, on any of the 2023 Notes, when the interest becomes due and payable, and continuance of such default for a period of 30 days;
(3) failure by the Company to comply with its obligation to convert the 2023 Notes in accordance with the 2023 Indenture upon exercise of a holder’s conversion right;
(4) failure by the Company to give a fundamental change notice or notice of a specified corporate transaction when due with respect to the Notes;
(5) failure by the Company to comply with any of its other agreements contained in the 2023 Notes or the 2023 Indenture for a period of 60 days after written notice from the Trustee or the holders of at least 25% in aggregate principal amount of the Notes then outstanding has been received;
(6) failure by the Company to pay when due the principal of, or acceleration of, any indebtedness for money borrowed by the Company or any of its Material Subsidiaries (as defined in the 2023 Indenture) in excess of $40.0 million principal amount, if such indebtedness is not discharged, or such acceleration is not annulled, for a period of 30 days after written notice to the Company by the Trustee or to the Company and the Trustee by holders of 25% or more in aggregate principal amount of the 2023 Notes then outstanding in accordance with the 2023 Indenture; and
(7) certain events of bankruptcy, insolvency or reorganization of the Company or any of its Material Subsidiaries (as defined in the Indenture).
If such an event of default, other than an event of default described in clause (7) above with respect to the Company, occurs and is continuing, the Trustee by written notice to the Company, or the holders of at least 25% in aggregate principal amount of the outstanding Notes by notice to the Company and the Trustee, may, and the Trustee at the request of such holders shall, declare 100% of the principal of and accrued and unpaid interest, if any, on all the Notes then outstanding to be due and payable. If an event of default described in clause (7) above occurs, 100% of the principal of and accrued and unpaid interest on the Notes then outstanding will automatically become due and payable.
Note Hedges and Warrants. On November 14, 2017 and November 16, 2017, in connection with the 2023 Notes, the Company entered into privately negotiated convertible note hedge transactions (the “Convertible Note Hedge Transactions”) with respect to the Company’s common stock, par value $0.001 per share (the “Common Stock”), with certain bank

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (Continued)

counterparties (the “Counterparties”). The Company paid an aggregate amount of approximately $33.5 million to the Counterparties for the Convertible Note Hedge Transactions. The Convertible Note Hedge Transactions cover, subject to anti-dilution adjustments substantially similar to those in the 2023 Notes, approximately 9.1 million shares of Common Stock, the same number of shares underlying the 2023 Notes, at a strike price that corresponds to the initial conversion price of the 2023 Notes, and are exercisable upon conversion of the 2023 Notes. The Convertible Note Hedge Transactions will expire upon the maturity of the 2023 Notes. The Convertible Note Hedge Transactions are intended to reduce the potential economic dilution upon conversion of the 2023 Notes. The Convertible Note Hedge Transactions are separate transactions and are not part of the terms of the 2023 Notes. Holders of the 2023 Notes will not have any rights with respect to the Convertible Note Hedge Transactions.
In addition, concurrently with entering into the Convertible Note Hedge Transactions, the Company separately entered into privately negotiated warrant transactions, whereby the Company sold to the Counterparties warrants (the “Warrants”) to acquire, collectively, subject to anti-dilution adjustments, approximately 9.1 million shares of the Common Stock at an initial strike price of approximately $23.30 per share, which represents a premium of 60% over the last reported sale price of the Common Stock of $14.56 on November 14, 2017. The Company received aggregate proceeds of approximately $23.2 million from the sale of the Warrants to the Counterparties. The Warrants are separate transactions and are not part of the 2023 Notes or Convertible Note Hedge Transactions. Holders of the 2023 Notes and Convertible Note Hedge Transactions will not have any rights with respect to the Warrants.
The amounts paid and received for the Convertible Note Hedge Transactions and Warrants have been recorded in additional paid-in capital in the consolidated balance sheets. The fair value of the Convertible Note Hedge Transactions and Warrants are not re-measured through earnings each reporting period. The amounts paid for the Convertible Note Hedge Transactions are tax deductible expenses, while the proceeds received from the Warrants are not taxable.
Impact to Earnings per Share. The 2023 Notes will have no impact to diluted earnings per share until the average price of our Common Stock exceeds the conversion price of $18.93 per share because the principal amount of the 2023 Notes is required to be settled in cash upon conversion. Under the treasury stock method, in periods the Company reports net income, the Company is required to include the effect of additional shares that may be issued under the 2023 Notes when the price of the Company’s Common Stock exceeds the conversion price. Under this method, the cumulative dilutive effect of the 2023 Notes would be approximately 9.1 million shares if the average price of the Company’s Common Stock is $18.93. However, upon conversion, there will be no economic dilution from the 2023 Notes, as exercise of the Convertible Note Hedge Transactions eliminates any dilution from the 2023 Notes that would have otherwise occurred when the price of the Company’s Common Stock exceeds the conversion price. The Convertible Note Hedge Transactions are required to be excluded from the calculation of diluted earnings per share, as they would be anti-dilutive under the treasury stock method.
The warrants will have a dilutive effect when the average share price exceeds the warrant’s strike price of $23.30 per share. However, upon conversion, the Convertible Note Hedge Transactions would neutralize the dilution from the 2023 Notes so that there would only be dilution from the warrants.
1.125% Convertible Senior Notes due 2018.On August 16, 2013, the Company issued $138.0 million aggregate principal amount of 1.125% convertible senior notes pursuant to an indenture (the "Indenture"“2018 Indenture”) by and between the Company and U.S. Bank, National Association as the trustee. The 2018 Notes will maturematured on August 15, 2018 (the "Maturity Date"“Maturity Date”), subject to earlier repurchase or conversion. In accounting for the 2018 Notes at issuance, the Company separated the 2018 Notes into liability and equity components pursuant to the accounting standards for convertible debt instruments that may be fully or partially settled in cash upon conversion. As of the date of issuance, the Company determined that the liability component of the 2018 Notes was $107.7 million and the equity component of the 2018 Notes was $30.3 million. The fair value of the liability component was estimated using an interest rate for a similar instrument without a conversion feature. The unamortized discount related to the 2018 Notes is beingwas amortized to interest expense using the effective interest method over five years through August 2018.

The Company will paypaid cash interest at an annual rate of 1.125% of the principal amount at issuance, payable semi-annually in arrears on February 15 and August 15 of each year, commencing on February 15, 2014. The Company incurred transaction

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (Continued)

costs of approximately $3.6 million related to the issuance of 2018 Notes. In accounting for these costs, the Company allocated the costs to the liability and equity components in proportion to the allocation of proceeds from the issuance of the 2018 Notes to such components. Transaction costs allocated to the liability component of $2.8 million were recorded as deferred offering costs and are beingwere amortized to interest expense using the effective interest method over five years (the expected term of the debt). The transaction costs allocated to the equity component of $0.8 million were recorded as additional paid-in capital. The 2018 Notes arewere the Company'sCompany’s general unsecured obligations, ranking equally in right of payment to all of Rambus’ existing and future

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (Continued)

senior unsecured indebtedness, including the 20142023 Notes, and senior in right of payment to any of the Company’s future indebtedness that is expressly subordinated to the 2018 Notes.

The 2018 Notes arewere convertible into shares of the Company’s common stock at an initial conversion rate of 82.8329 shares of common stock per $1,000 principal amount of 2018 Notes, subject to adjustment in certain events. This is equivalent to an initial conversion price of approximately $12.07 per share of common stock. Holders may surrenderhave surrendered their 2018 Notes for conversion prior to the close of business day immediately preceding May 15, 2018 only under the following circumstances: (1) during any calendar quarter commencing after the calendar quarter ending on December 31, 2013 (and only during such calendar quarter), if the closing sale price of the common stock for 20 days or more trading days (whether or not consecutive) during a period of 30 days consecutive trading days ending on the last trading day of the immediately preceding calendar quarter is more than 130% of the conversion price per share of common stock on the last trading day of the preceding calendar quarter; (2) during the five business day period after any five consecutive trading day period (the ‘‘measurement period’’) in which the trading price (as defined below) per $1,000 principal amount of notes for each trading day of the measurement period was less than 98% of the product of the closing sale price of the Company'sCompany’s common stock and the conversion rate on each such trading day; (3) upon the occurrence of specified distributions to holders of the Company'sCompany’s common stock; or (4) upon the occurrence of specified corporate events. On or after May 15, 2018 until the close of business on the second scheduled trading day immediately preceding the Maturity Date, holders may converthave converted their notes at any time, regardless of the foregoing circumstances. If a holder electselected to convert its 2018 Notes in connection with certain fundamental changes, as that term is defined in the 2018 Indenture, that occuroccurred prior to the Maturity Date, the Company will,would have, in certain circumstances, increaseincreased the conversion rate for 2018 Notes converted in connection with such fundamental changes by a specified number of shares of common stock.

Upon conversion of the 2018 Notes, the Company will payhave paid cash up to the aggregate principal amount of the notes to behave been converted and paypaid or deliver,delivered, as the case may be, cash, shares of the Company'sCompany’s common stock or a combination of cash and shares of the Company'sCompany’s common stock, at the Company'sCompany’s election, in respect of the remainder, if any, of the Company'sCompany’s conversion obligation in excess of the aggregate principal amount of the notes being converted, as specified in the Indenture.

The Company may not redeemhave redeemed the 2018 Notes at its option prior to the Maturity Date, and no sinking fund iswas provided for the 2018 Notes.

Upon the occurrence of a fundamental change, holders may requirehave required the Company to repurchase for cash all or any portion of their notes at a repurchase price equal to 100% of the principal amount of the notes to be repurchased, plus accrued and unpaid interest to, but excluding, the fundamental change repurchase date.

The following events are considered events of default under the Indenture which may resulthave resulted in the acceleration of the maturity of the 2018 Notes:

(1) default in the payment when due of any principal of any of the notes at maturity, upon redemption or upon exercise of a repurchase right or otherwise;

(2) default in the payment of any interest, including additional interest, if any, on any of the notes, when the interest becomesbecame due and payable, and continuance of such default for a period of 30 days;

(3) the Company'sCompany’s failure to deliver cash or cash and shares of the Company'sCompany’s common stock (including any additional shares deliverable as a result of a conversion in connection with a make-whole fundamental change, as defined in the Indenture) when required by the Indenture;

(4) default in the Company'sCompany’s obligation to provide notice of the occurrence of a fundamental change, make-whole fundamental change or distribution to holders of the Company'sCompany’s common stock when required by the Indenture;


NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (Continued)

(5) the Company'sCompany’s failure to comply with any of the Company'sCompany’s other agreements in the notes or the 2018 Indenture (other than those referred to in clauses (1) through (4) above) for 60 days after the Company'sCompany’s receipt of written notice to the Company of such default from the trustee or to the Company and the trustee of such default from holders of not less than 25% in aggregate principal amount of the 2018 Notes then outstanding;

(6) the Company'sCompany’s failure to pay when due the principal of, or acceleration of, any indebtedness for money borrowed by the Company or any of the Company'sCompany’s material subsidiaries in excess of $40 million principal amount, if such indebtedness is not discharged, or such acceleration is not annulled, for a period of 30 days after written notice thereof is delivered to the Company by the trustee or to the Company and the trustee by the holders of 25% or more in aggregate principal amount of the notes then

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (Continued)

outstanding without such failure to pay having been cured or waived, such acceleration having been rescinded or annulled (if applicable) and such indebtedness not having been paid or discharged; and

(7) certain events of bankruptcy, insolvency or reorganization relating to the Company or any of the Company'sCompany’s material subsidiaries (as defined in the Indenture).

If an event of default, other than an event of default described in clause (7) above with respect to the Company, occursoccurred and iswas continuing, either the trustee or the holders of at least 25% in aggregate principal amount of the notes then outstanding may declarehave declared the principal amount of, and accrued and unpaid interest, including additional interest, if any, on the notes then outstanding to be immediately due and payable. If an event of default described in clause (7) above occursoccurred with respect to the Company, the principal amount of and accrued and unpaid interest, including additional interest, if any, on the notes will have automatically become immediately due and payable.

5% Convertible Senior Notes due 2014. On June 29, 2009, the Company issued $150.0 million aggregate principal amount of 5% convertible senior notes due June 15, 2014. As of the date of issuance, the Company determined that the liability component of the 2014 Notes was approximately $92.4 million and the equity component was approximately $57.6 million. On July 10, 2009, an additional $22.5 million of the 2014 Notes were issued as a result of the underwriters exercising their overallotment option. As of the date of issuance of the $22.5 million 2014 Notes, the Company determined that the liability component was approximately $14.3 million, and the equity component was approximately $8.2 million. The unamortized discount related to the 2014 Notes was being amortized to interest expense using the effective interest method over five years through June 2014.
The Company paid cash interest at an annual rate of 5% of the principal amount at issuance, payable semi-annually in arrears on June 15 and December 15 of each year, beginning on December 15, 2009. During 2014, the Company paid approximately $4.3 million of interest related to the 2014 Notes. During 2013, the Company paid approximately $8.6 million of interest related to the 2014 Notes. Issuance costs were approximately $5.1 million of which $3.2 million is related to the liability portion, which is being amortized to interest expense over five years (the expected term of the debt), and $1.9 million is related to the equity portion. The 2014 Notes were the Company’s general unsecured obligation, ranking equal in right of payment to all of the Company’s existing and future senior indebtedness and were senior in right of payment to any of the Company’s future indebtedness that was expressly subordinated to the 2014 Notes.
The 2014 Notes were convertible into shares of the Company’s Common Stock at an initial conversion rate of 51.8 shares of Common Stock per $1,000 principal amount of 2014 Notes. This was equivalent to an initial conversion price of approximately $19.31 per share of common stock. Holders could have surrendered their 2014 Notes for conversion prior to March 15, 2014 only under the following circumstances: (i) during any calendar quarter beginning after the calendar quarter ending September 30, 2009, and only during such calendar quarter, if the closing sale price of the Common Stock for 20 days or more trading days in the period of 30 days consecutive trading days ending on the last trading day of the immediately preceding calendar quarter exceeded 130% of the conversion price in effect on the last trading day of the immediately preceding calendar quarter, (ii) during the five business day period after any 10 days consecutive trading day period in which the trading price per $1,000 principal amount of 2014 Notes for each trading day of such 10 days consecutive trading day period was less than 98% of the product of the closing sale price of the Common Stock for such trading day and the applicable conversion rate, (iii) upon the occurrence of specified distributions to holders of the Common Stock, (iv) upon a fundamental change of the Company as specified in the Indenture governing the 2014 Notes, or (v) if the Company calls any or all of the 2014 Notes for redemption, at any time prior to the close of business on the business day immediately preceding the redemption date. On and after March 15, 2014, holders may convert their 2014 Notes at any time until the close of business on the third business day prior to the maturity date, regardless of the foregoing circumstances.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (Continued)

Upon conversion of the 2014 Notes, the Company would have paid (i) cash equal to the lesser of the aggregate principal amount and the conversion value of the 2014 Notes and (ii) shares of the Company’s Common Stock for the remainder, if any, of the Company’s conversion obligation, in each case based on a daily conversion value calculated on a proportionate basis for each trading day in the 20 days trading day conversion reference period as further specified in the Indenture.
The Company was not able to redeem the 2014 Notes at its option prior to June 15, 2012. At any time on or after June 15, 2012, the Company had the right, at its option, to redeem the 2014 Notes in whole or in part for cash in an amount equal to 100% of the principal amount of the 2014 Notes to be redeemed, together with accrued and unpaid interest, if any, if the closing sale price of the Common Stock for at least 20 days of the 30 days consecutive trading days immediately prior to any date the Company gives a notice of redemption was greater than 130% of the conversion price on the date of such notice.
Upon the occurrence of a fundamental change, holders could have required the Company to repurchase some or all of their 2014 Notes for cash at a price equal to 100% of the principal amount of the 2014 Notes being repurchased, plus accrued and unpaid interest, if any. In addition, upon the occurrence of certain fundamental changes, as that term is defined in the Indenture, the Company would have, in certain circumstances, increased the conversion rate for the 2014 Notes converted in connection with such fundamental changes by a specified number of shares of Common Stock, not to exceed 15.5401 per $1,000 principal amount of the 2014 Notes.
The following events were considered “Events of Default” under the Indenture which would have resulted in the acceleration of the maturity of the 2014 Notes:
(1)default in the payment when due of any principal of any of the 2014 Notes at maturity, upon redemption or upon exercise of a repurchase right or otherwise;
(2)default in the payment of any interest, including additional interest, if any, on any of the 2014 Notes, when the interest becomes due and payable, and continuance of such default for a period of 30 days;
(3)the Company’s failure to deliver cash or cash and shares of Common Stock (including any additional shares deliverable as a result of a conversion in connection with a make-whole fundamental change) when required to be delivered upon the conversion of any 2014 Note;
(4)default in the Company’s obligation to provide notice of the occurrence of a fundamental change when required by the Indenture;
(5)
the Company’s failure to comply with any of its other agreements in the 2014 Notes or the Indenture (other than those referred to in clauses (1) through (4) above) for 60 days after the Company’s receipt of written notice to the Company of such default from the trustee or to the Company and the trustee of such default from holders of not less than 25% in aggregate principal amount of the 2014 Notes then outstanding;
(6)
the Company’s failure to pay when due the principal of, or acceleration of, any indebtedness for money borrowed by the Company or any of its subsidiaries in excess of $30 million principal amount, if such indebtedness is not discharged, or such acceleration is not annulled, by the end of a period of ten days after written notice to the Company by the trustee or to the Company and the trustee by the holders of at least 25% in aggregate principal amount of the 2014 Notes then outstanding; and
(7)certain events of bankruptcy, insolvency or reorganization relating to the Company or any of its material subsidiaries (as defined in the Indenture).
If an event of default, other than an event of default in clause (7) above with respect to the Company occurs and is continuing, either the trustee or the holders of at least 25% in aggregate principal amount of the 2014 Notes then outstanding may declare the principal amount of, and accrued and unpaid interest, including additional interest, if any, on the 2014 Notes then outstanding to be immediately due and payable. If an event of default described in clause (7) above occurs with respect to the Company the principal amount of and accrued and unpaid interest, including additional interest, if any, on the 2014 Notes will automatically become immediately due and payable.
During the second quarter of 2014,2018, the Company paid upon maturity the entire $172.5remaining $81.2 million in aggregate principal amount of the 20142018 Notes. Additionally, the Company delivered 423,873 shares of the Company’s common stock as settlement related to the in-the-money conversion feature of the 2018 Notes at maturity. The value of the shares delivered was approximately $5.0 million.
During the fourth quarter of 2017, the Company repurchased $56.8 million aggregate principal amount of the 2018 Notes for a price of $72.3 million which resulted in a loss on extinguishment of debt of $1.1 million and $16.6 million being recorded in stockholders’ equity. To determine the impact of the repurchase on stockholders’ equity, the Company first determined the fair value of the liability component of the repurchased 2018 Notes immediately prior to the repurchase. The Company then reduced the amount paid for the repurchased 2018 Notes by the fair value of the liability component and allocated the remaining amount paid to the equity component, which resulted in a reduction to stockholders’ equity.
Additional paid-in capital at December 31, 20162019 and December 31, 20152018 includes $93.4$111.3 million and $111.3 million, respectively, for each year related to the equity component of the notes.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (Continued)

As of December 31, 2016,2019, none of the conversion conditions were met related to the 20182023 Notes. Therefore, the classification of the entire equity component for the 20182023 Notes in permanent equity is appropriate as of December 31, 2016.2019.
Interest expense related to the notes for the years ended December 31, 2016, 20152019, 2018 and 20142017 was as follows:
 Years Ended December 31,
 2019 2018 2017
 (in thousands)
2023 Notes coupon interest at a rate of 1.375%$2,372
 $2,372
 $290
2023 Notes amortization of discount and debt issuance cost at an additional effective interest rate of 4.9%6,854
 6,486
 768
2018 Notes coupon interest at a rate of 1.125%
 377
 1,488
2018 Notes amortization of discount and debt issuance cost at an additional effective interest rate of 5.5%
 2,756
 6,810
Total interest expense on convertible notes$9,226
 $11,991
 $9,356

 Years Ended December 31,
 2016 2015 2014
 (in thousands)
2018 Notes coupon interest at a rate of 1.125%$1,553
 $1,567
 $1,567
2018 Notes amortization of discount and debt issuance cost at an additional effective interest rate of 5.5%6,749
 6,372
 6,019
2014 Notes coupon interest at a rate of 5%
 
 3,929
2014 Notes amortization of discount at an additional effective interest rate of 11.7%
 
 8,744
Total interest expense on convertible notes$8,302
 $7,939
 $20,259


11.13. Commitments and Contingencies
On December 15, 2009, the Company entered into a lease agreement for approximately 125,000 square feet of office space located at 1050 Enterprise Way in Sunnyvale, California commencing on July 1, 2010 and expiring on June 30, 2020. The office space is used for the Company’s corporate headquarters, as well as engineering, sales, marketing and administrative operations and activities. The annual base rent for these leases includes certain rent abatement and increases annually over the lease term. The Company has two2 options to extend the lease for a period of 60 months each and a one-time option to terminate the lease after 84 months in exchange for an early termination fee. Pursuant to the terms of the lease, the landlord agreed to reimburse the Company approximately $9.1$9.1 million,, which was received by the year ended December 31, 2011. The Company recognized the reimbursement as an additional imputed financing obligation as such payment from the landlord is deemed to be an imputed financing obligation. On November 4, 2011, to better plan for future expansion, the Company entered into an amended lease for its Sunnyvale facility for approximately an additional 31,000-square-foot31,000 square-foot space commencing on March 1, 2012 and expiring on June 30, 2020. Additionally, a tenant improvement allowance to be provided by the landlord was approximately $1.7 million.$1.7 million.On

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (Continued)

September 29, 2012, the Company entered into a second amended Sunnyvale lease to reduce the tenant improvement allowance to approximately $1.5 million.$1.5 million. On January 31, 2013, the Company entered into a third amendment to the Sunnyvale lease to surrender the 31,000 square-foot space from the first amendment back to the landlord and recorded a total charge of $2.0 million related to the surrender of the amended lease.

Refer to Note 10, “Leases,” for information regarding the Company’s lease agreement for a new corporate headquarters in San Jose, California.
On March 8, 2010, the Company entered into a lease agreement for approximately 25,000 square feet of office and manufacturing areas, located in Brecksville, Ohio. The office area iswas used for the RLD group’slighting division’s engineering activities while the manufacturing area iswas used for the manufacture of prototypes. This lease was amended on September 29, 2011to expand the facility to approximately 51,000 total square feet and the amended lease will expireexpired on July 31, 2019. The Company hashad an option to extend the lease for a period of 60 months.months. During 2018, the Company closed its lighting division and manufacturing operations in Brecksville, Ohio, and sold the related equipment. Refer to Note 18, “Restructuring and Other Charges,” for additional details.
The Company undertook a series of structural improvements to ready the Sunnyvale and Brecksville facilities for its use. Since these improvements were considered structural in nature and the Company was responsible for any cost overruns, for accounting purposes, the Company was treated in substance as the owner of each construction project during the construction period. At the completion of each construction, the Company concluded that it retained sufficient continuing involvement to preclude de-recognition of the building under the FASB authoritative guidance applicable to the sale leasebacks of real estate. As such, prior to January 1, 2019 when the New Leasing Standard became effective for the Company, continues to accountthe Company accounted for the buildings as owned real estate and to recordrecorded an imputed financing obligation for its obligations to the legal owners. Upon adoption of the New Leasing Standard, these leases were treated as operating leases.
MonthlyPrior to the adoption of the New Leasing Standard, monthly lease payments on these facilities arewere allocated between the land element of the lease (which iswas accounted for as an operating lease) and the imputed financing obligation. The imputed financing obligation iswas amortized using the effective interest method and the interest rate was determined in accordance with the requirements of sale leaseback accounting. For the years ended December 31, 2016, 20152018 and 2014,2017, the Company recognized in its Consolidated Statements of Operations $4.3 million and $4.4 million,$4.5 million, and $4.5 million, respectively, of interest expense in connection with the imputed financing obligation on these facilities. At As of December 31, 2016 and 2015,2018, the imputed financing obligation balance in connection with these facilities

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (Continued)

was $38.9$37.6 million, and $39.3 million, respectively, which was primarily classified under long-term imputed financing obligation.
As of December 31, 2016 and 2015,2018, the Company had capitalized $40.3 million in property, plant and equipment based on the estimated fair value of the portion of the pre-construction shell, construction costs related to the build-out of the facilities and capitalized interest during construction period. At the end of the initial lease term, should the Company decide not to renew the lease, the Company would reverse the equal amounts of the net book value of the building and the corresponding imputed financing obligation.
On June 29, 2009,November 17, 2017, the Company entered into an Indenture with U.S. Bank, National Association, as trustee, relating to the issuance by the Company of $150.0 million aggregate principal amount of the 2014 Notes. On July 10, 2009, an additional $22.5 million in aggregate principal amount of 2014 Notes were issued as a result of the underwriters exercising their overallotment option. During the second quarter of 2014, the Company paid upon maturity the entire $172.5 million in aggregate principal amount of the 2014 Notes.
On August 16, 2013, the Company entered into an Indenture with U.S. Bank, National Association, as trustee, relating to the issuance by the Company of $138.0 million aggregate principal amount of the 20182023 Notes. The aggregate principal amount of the 2018 notes2023 Notes as of December 31, 2016 and 20152019 was $138.0$172.5 million, offset by unamortized debt discount and unamortized debt issuance costs of $10.9 million and $0.9 million, respectively, and $17.1$22.2 million and $1.5 million, respectively, on the accompanying consolidated balance sheets. The unamortized discount related to the 20182023 Notes is being amortized to interest expense using the effective interest method over the remaining 20 months3.1 years until maturity of the 20182023 Notes on August 15, 2018. The unamortized debt issuance costs relateFebruary 1, 2023. Refer to the adoption of ASU 2015-03 during the first quarter of 2016. See Note 10,12, “Convertible Notes,” for additional details.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (Continued)

As of December 31, 2016,2019, the Company’s material contractual obligations arewere as follows (in thousands):
Total 2017 2018 2019 2020 2021 ThereafterTotal 2020 2021 2022 2023 2024
Contractual obligations (1)             
Imputed financing obligation (2)$22,220
 $6,302
 $6,447
 $6,602
 $2,869
 $
 $
Leases and other contractual obligations10,837
 5,649
 2,606
 1,432
 603
 543
 4
Contractual obligations (1) (2)           
Other contractual obligations$468
 $234
 $234
 $
 $
 $
Software licenses (3)24,255
 10,497
 10,226
 3,532
 
 
 
31,530
 13,525
 11,977
 6,028
 
 
Acquisition retention bonuses (4)9,998
 3,499
 3,499
 3,000
 
 
Convertible notes138,000
 
 138,000
 
 
 
 
172,500
 
 
 
 172,500
 
Interest payments related to convertible notes3,105
 1,553
 1,552
 
 
 
 
8,308
 2,372
 2,372
 2,372
 1,192
 
Total$198,417
 $24,001
 $158,831
 $11,566
 $3,472
 $543
 $4
$222,804
 $19,630
 $18,082
 $11,400
 $173,692
 $

(1)
The above table does not reflect possible payments in connection with uncertainunrecognized tax benefits of approximately $21.9$24.6 million including $19.7$22.8 million recorded as a reduction of long-term deferred tax assets and $2.2$1.8 million in long-term income taxes payable, as of December 31, 2016.2019. As noted below in Note 16,19, “Income Taxes,” although it is possible that some of the unrecognized tax benefits could be settled within the next 12 months, the Company cannot reasonably estimate the outcome at this time.
(2)For the Company’s lease commitments as of December 31, 2019, refer to Note 10, “Leases.”
(3)The Company has commitments with various software vendors for agreements generally having terms longer than one year.
(4)In connection with the acquisitions of Northwest Logic in August 2019 and the Secure Silicon IP and Protocols business in December 2019, the Company is obligated to pay retention bonuses to certain employees subject to certain eligibility and acceleration provisions including the condition of employment.
Refer to Note 3, “Recent Accounting Pronouncements” and Note 10, “Leases,” for a discussion related to the Company’s facility leases due to the adoption of the New Leasing Standard on January 1, 2019.
Additionally, the Company’s lease-related obligations as of December 31, 2018, as determined under the prior accounting standard, were as follows (in thousands):
 Total 2019 2020 2021 2022 2023
Lease-related obligations           
Imputed financing obligation (1)$8,081
 $5,677
 $2,404
 $
 $
 $
Leases19,415
 5,333
 4,883
 4,960
 3,271
 968
Total$27,496
 $11,010
 $7,287
 $4,960
 $3,271
 $968
_________________________________________
(1)With respect to the imputed financing obligation, the main components of the difference between the amount reflected in the contractual obligations table above and the amount reflected on the Consolidated Balance Sheetsconsolidated balance sheet are the interest on the imputed financing obligation and the estimated common area expenses over the future periods. The amount includes the amended Ohio lease and the amended Sunnyvale lease.
(3)
The Company has commitments with various software vendors for non-cancellable agreements generally having terms longer than one year.
Rent expense was approximately $3.8 million, $2.7 million and $2.6 million for the years ended December 31, 2016, 2015 and 2014, respectively.
Indemnifications

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (Continued)

From time to time, the Company indemnifies certain customers as a necessary means of doing business. Indemnification covers customers for losses suffered or incurred by them as a result of any patent, copyright, or other intellectual property infringement or any other claim by any third party arising as result of the applicable agreement with the Company. The Company generally attempts to limit the maximum amount of indemnification that the Company could be required to make under these agreements to the amount of fees received by the Company, however, this is not always possible. The fair value of the liability as of December 31, 20162019 and 2015 is2018 was not material.

12.NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (Continued)

14. Equity Incentive Plans and Stock-Based Compensation
Stock OptionEquity Incentive Plans
The Company has two stock optionthree equity incentive plans under which grants are currently outstanding: the 2006 Equity Incentive Plan (the “2006 Plan”) and, the 2015 Equity Incentive Plan (the “2015 Plan”) and the 2019 Inducement Equity Incentive Plan (the “2019 Inducement Plan”). On April 23, 2015, the Company'sCompany’s stockholders approved the 2015 Plan, which authorizes 4,000,000replaced the 2006 Plan. Additionally, in the third quarter of 2019, the Company adopted the 2019 Inducement Plan and, subject to the adjustment provisions of the 2019 Inducement Plan, reserved 400,000 shares of the Company’s common stock for future issuance plus the number of shares that remained available for grantpursuant to equity awards granted under the 2006 Plan as of the effective date of the 20152019 Inducement Plan. The 2015 Plan became effective and replaced the 20062019 Inducement Plan on April 23, 2015. The 2015 Plan waswere the Company’s only planplans for providing stock-based incentive awards to eligible employees, executive officers, non-employee directors and consultants as of December 31, 2016.2019. Grants under all plans typically have a requisite service period of 60 months or 48 months, have straight-line vesting schedules and expire not more than 10 years from date of grant. No further awards will be made under the 2006 Plan, but the 2006 Plan will continue to govern awards previously granted under it. In addition, any shares subject to stock options or other awards granted under the 2006 Plan that on or after the effective date of the 2015 Plan are forfeited, cancelled, exchanged or surrendered or terminate under the 2006 Plan will become available for grant under the 2015 Plan. The Board will periodically review actual share consumption under the 2015 Plan and may make a request for additional shares as needed.
The 20062019 Inducement Plan was approved by the stockholders in May 2006. The 2006 Plan, as amended, provides for the issuancegrant of the following types of incentive awards: (i)equity-based awards, including nonstatutory stock options; (ii)options, restricted stock units, restricted stock, stock appreciation rights; (iii) restricted stock; (iv) restricted stock units; (v)rights, performance shares and performance units;units, and (vi) other stock or cash awards. This plan provides forits terms are substantially similar to the granting of awards at less than fair market value of the common stock on the date of grant, but such grants would be counted against the numerical limits of available shares at a ratio of 1.5 to 1.0. The Board of Directors reserved 8,400,000 shares in March 2006 for issuance under this plan, subject to stockholder approval. Upon stockholder approval of this Plan on May 10, 2006, the 1997 Stock Option Plan (the "1997 Plan") was replaced and the 1999 Non-statutory Stock Option Plan (the "1999 Plan") was terminated. There are no outstanding options from the 1997 Plan or 1999 Plan as of December 31, 2016. On April 30, 2009 and April 26, 2012, stockholders approved an additional 6,500,000 shares on each date for issuance under the 2006Company’s 2015 Plan. Additionally, on April 24, 2014, stockholders approved an additional 10,000,000 shares for issuance under the 2006 Plan. Those who were eligible forHowever, awards under the 20062019 Inducement Plan includedmay only be granted to individuals who previously have not been employees or non-employee directors and consultantsof the Company (or who provide serviceswill become employed following a bona fide period of non-employment or service with the Company), as an inducement material to the individuals’ entry into employment with the Company, and its affiliates. These options typically have a requisite service period of 60 monthsor, 48 months, have straight-line vesting schedules, and expire ten years from date of grant.
As of December 31, 2016, 7,305,368 sharesto the extent permitted by Rule 5635(c)(3) of the 35,400,000 shares approved under the plans remain available for grant. The 2015 Plan is now the Company’s only plan for providing stock-based incentive compensation to eligible employees, directors and consultants.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (Continued)

Nasdaq Listing Rules, in connection with a merger or acquisition.
A summary of shares available for grant under the Company’s plans is as follows:
 Shares Available for Grant
Shares available as of December 31, 20132,527,428
Increase in shares approved for issuance10,000,000
Stock options granted(2,370,313)
Stock options forfeited1,400,349
Stock options expired under former plans(373,043)
Nonvested equity stock and stock units granted (1)(585,753)
Nonvested equity stock and stock units forfeited (1)125,560
Total shares available for grant as of December 31, 201410,724,228
Increase in shares approved for issuance4,000,000
Stock options granted(362,335)
Stock options forfeited1,624,823
Stock options expired under former plans(657,878)
Nonvested equity stock and stock units granted (1) (2)(4,537,797)
Nonvested equity stock and stock units forfeited (1)382,504
Total shares available for grant as of December 31, 201511,173,545
Stock options granted(500,000)
Stock options forfeited1,081,107
Stock options expired under former plans(412,467)
Nonvested equity stock and stock units granted (1) (3)(5,316,675)
Nonvested equity stock and stock units forfeited (1)1,279,858
Total shares available for grant as of December 31, 20167,305,368
Stock options granted(558,426)
Stock options forfeited1,978,042
Nonvested equity stock and stock units granted (1) (2)(5,007,947)
Nonvested equity stock and stock units forfeited (1)1,334,110
Total shares available for grant as of December 31, 20175,051,147
Increase in shares approved for issuance5,500,000
Stock options granted(711,479)
Stock options forfeited877,803
Nonvested equity stock and stock units granted (1) (3)(4,993,802)
Nonvested equity stock and stock units forfeited (1)4,350,377
Total shares available for grant as of December 31, 201810,074,046
Increase in shares approved for issuance (5)400,000
Stock options granted(80,000)
Stock options forfeited426,960
Nonvested equity stock and stock units granted (1) (4)(7,261,845)
Nonvested equity stock and stock units forfeited (1)3,267,702
Total shares available for grant as of December 31, 20196,826,863

(1)
For purposes of determining the number of shares available for grant under the 2015 Plan against the maximum number of shares authorized, each restricted stock granted reduces the number of shares available for grant by 1.5 shares and each restricted stock forfeited increases shares available for grant by 1.5 shares.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (Continued)

(2)
Amount includes 238,9800.4 million shares that had been reserved for potential future issuance related to certain performance unit awards discussed under the section titled "Nonvested“Nonvested Equity Stock and Stock Units"Units” below.
(3)
Amount includes 300,0030.5 million shares that have been reserved for potential future issuance related to certain performance unit awards discussed under the section titled "Nonvested“Nonvested Equity Stock and Stock Units"Units” below.


NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (Continued)

(4)Amount includes 1.0 million shares that have been reserved for potential future issuance related to certain performance unit awards discussed under the section titled “Nonvested Equity Stock and Stock Units” below.
(5)Shares were reserved under the 2019 Inducement Plan adopted in the third quarter of 2019.
General Stock Option Information
The following table summarizes stock option activity under the stock optionCompany’s equity incentive plans for the years ended December 31, 20162019, 20152018 and 20142017 and information regarding stock options outstanding, exercisable, and vested and expected to vest as of December 31, 2016.
 Options Outstanding Weighted Average Remaining Contractual Term  
 Number of Shares Weighted Average Exercise Price per Share  Aggregate Intrinsic Value
 (Dollars in thousands, except per share amounts)
Outstanding as of December 31, 201311,377,146 $11.32
    
Options granted2,370,313 $9.63
    
Options exercised(905,464) $6.93
    
Options forfeited(1,400,349) $16.13
    
Outstanding as of December 31, 201411,441,646 $10.73
    
Options granted362,335 $11.27
    
Options exercised(1,184,141) $7.42
    
Options forfeited(1,624,823) $17.22
    
Outstanding as of December 31, 20158,995,017 $10.01
    
Options granted500,000 $12.29
    
Options exercised(1,405,077) $7.27
    
Options forfeited(1,081,107) $18.98
    
Outstanding as of December 31, 20167,008,833 $9.34
 5.0 $37,202
Vested or expected to vest at December 31, 20166,880,321 $9.34
 4.9 $36,603
Options exercisable at December 31, 20164,752,346 $10.05
 4.3 $23,812
During the years ended December 31, 2016, 2015 and 2014, no stock options that contain a market condition were granted. During the year ended December 31, 2012, 1,795,000 stock options that contain a market condition were granted. These options vest in three years if specified stock prices are achieved. As of December 31, 2016 and 2015, there were 1,135,000 and 1,315,000, respectively, stock options outstanding that require the Company to achieve minimum market conditions in order for the options to become exercisable. The fair values of the options granted with a market condition were calculated using a binomial valuation model, which estimates the potential outcome of reaching the market condition based on simulated future stock prices.
The aggregate intrinsic value in the table above represents the total pre-tax intrinsic value for in-the-money options at December 31, 2016, based on the $13.77 closing stock price of Rambus’ Common Stock on December 31, 2016 on the NASDAQ Global Select Market, which would have been received by the option holders had all option holders exercised their options as of that date. The total number of in-the-money options outstanding and exercisable as of December 31, 2016 was 5,849,154 and 3,617,874, respectively.
The following table summarizes the information about stock options outstanding and exercisable as of December 31, 20162019:

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (Continued)

 Options Outstanding Weighted Average Remaining Contractual Term  
 Number of Shares Weighted Average Exercise Price per Share  Aggregate Intrinsic Value
 (Dollars in thousands, except per share amounts)
Outstanding as of December 31, 20167,008,833 $9.34
    
Options granted558,426 $12.95
    
Options exercised(1,278,856) $7.34
    
Options forfeited(1,978,042) $10.68
    
Outstanding as of December 31, 20174,310,361 $9.78
    
Options granted711,479 $12.84
    
Options exercised(908,146) $6.70
    
Options forfeited(877,803) $13.73
    
Outstanding as of December 31, 20183,235,891 $10.25
    
Options granted80,000 $13.25
    
Options exercised(1,249,785) $7.79
    
Options forfeited(426,960) $13.71
    
Outstanding as of December 31, 20191,639,146 $11.37
 4.54 $4,631
Vested or expected to vest at December 31, 20191,627,218 $11.36
 4.49 $4,621
Options exercisable at December 31, 20191,319,210 $11.01
 3.63 $4,327
 Options Outstanding Options Exercisable
Range of Exercise PricesNumber Outstanding 
Weighted Average Remaining
Contractual Life (in years)
 Weighted Average Exercise Price Number Exercisable Weighted Average Exercise Price
$4.13 – $5.39651,904 5.0 $4.33
 109,740 $4.77
$5.46 – $5.46706,814 5.5 $5.46
 669,387
 $5.46
$5.49 – $5.63548,630 2.5 $5.63
 546,887 $5.63
$5.76 – $5.761,195,119 5.5 $5.76
 600,119 $5.76
$6.83 – $8.73667,795 4.0 $7.72
 644,421 $7.70
$8.76 – $8.76945,290 6.8 $8.76
 608,983 $8.76
$9.18 – $12.30708,832 7.5 $11.29
 351,337 $11.13
$12.31 – $18.69897,324 5.2 $14.82
 534,347 $16.42
$19.16 – $22.72686,500 1.0 $20.47
 686,500 $20.47
$23.60 – $23.60625 1.3 $23.60
 625 $23.60
$4.13 – $23.607,008,833 5.0 $9.34
 4,752,346 $10.05

Employee Stock Purchase Plans
During the yearyears ended December 31, 20162019, 2018, and 2017, the Company had one employee stock purchase plan, the 2015 Employee Stock Purchase Plan (“2015 ESPP”). During the year ended December 31, 2015, the Company had two employee stock purchase plans, the 2015 ESPP and the 2006 Employee Stock Purchase Plan (“2006 ESPP”). During the year ended December 31, 2014, the Company had one employee stock purchase plan, the 2006 ESPP.
On April 23, 2015, the Company's stockholders approved the 2015 ESPP which reserves 2,000,000 shares of the Company's common stock for purchase. The 2006 ESPP remained in effect until the Company’s November 2, 2015 offering period, at which time the 2015 ESPP became effective.
In March 2006, the Company adopted the 2006 ESPP, as amended, and reserved 1,600,000 shares, subject to stockholder approval which was received on May 10, 2006. On April 26, 2012, an additional 1,500,000 shares were approved by stockholders. On September 27, 2013, the Company filed a Registration Statement on Form S-8, registering 1,500,000 additional shares under the ESPP in connection with the commencement of the next subscription period under the ESPP. On April 24, 2014, the Company held its 2014 Annual Meeting of Stockholders where an amendment to the ESPP to increase the number of shares of common stock reserved for issuance under the ESPP by 1,500,000 shares was approved.
Employees generally will be eligible to participate in the plan if they are employed by Rambus for more than 20 hours per week and more than five months in a fiscal year. Both theThe 2015 ESPP and 2006 ESPP (when it was in effect) provideprovides for six month offering periods, with a new offering period commencing on the first trading day on or after May 1 and November 1 of each year. Under the plans, employees may purchase stock at the lower of 85% of the beginning of the offering period (the enrollment date), or the end of each offering period (the purchase date). Employees generally may not purchase more than the number of shares having a value greater than $25,000 in any calendar year, as measured at the purchase date.
The Company issued 548,357629,438 shares at a weighted average price of $9.34$8.53 per share during the year ended December 31, 20162019. The Company issued 544,391541,395 shares at a weighted average price of $9.369.99 per share during the year ended December 31, 20152018. The Company issued 596,188615,370 shares at a weighted average price of $8.2510.47 per share during the year ended December 31, 20142017. As of December 31, 20162019, 1,451,6431,665,440 shares under the ESPP remain available for issuance.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (Continued)

Stock-Based Compensation
Stock Options
During the years ended December 31, 20162019, 20152018 and 20142017, Rambus granted 500,000, 362,33580,000, 711,479 and 2,370,313558,426 stock options, respectively, with an estimated total grant-date fair value of $0.3 million, $3.0 million and $2.3 million,$1.7 million and $10.1 million, respectively. During the years ended December 31, 20162019, 20152018 and 20142017, Rambus recorded stock-based compensation related to stock options of $4.1$1.0 million, $7.2$1.7 million and $9.3$2.8 million,, respectively.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (Continued)

As of December 31, 20162019, there was $4.5$2.0 million of total unrecognized compensation cost, net of expected forfeitures, related to unvested stock-based compensation arrangements granted under the stock option plans. This cost is expected to be recognized over a weighted-average period of 1.32.3 years. The total fair value of options vested for the years ended December 31, 2016, 20152019, 2018 and 20142017 was $28.4$6.7 million, $41.4$12.9 million and $55.3$17.3 million,, respectively.
The total intrinsic value of options exercised was $8.0 million, $6.8 million and $4.4 million for the years ended December 31, 2016, 2015 and 2014, respectively. Intrinsic value is the total value of exercised shares based on the price of the Company’s Common Stock at the time of exercise less the proceeds received from the employees to exercise the options.
During the years ended December 31, 2016, 2015 and 2014, proceeds from employee stock option exercises totaled approximately $10.2 million, $8.8 million and $6.3 million, respectively.
Employee Stock Purchase Plans
During the years ended December 31, 20162019, 20152018 and 20142017, Rambus recorded stock-based compensation related to the ESPP of $1.6$1.5 million, $1.6$1.4 million and $2.6$1.7 million,, respectively. The compensation expense related to the ESPP for the year ended As of December 31, 2014 included compensation expense related to the increase in shares available for the ESPP which was approved by shareholders during the 2014 Annual Meeting of Stockholders. As of December 31, 20162019, there was $0.7 million of total unrecognized compensation cost related to stock-based compensation arrangements granted under the ESPP. That cost is expected to be recognized over four months.
There were no tax benefits realized as a result of employee stock option exercises, stock purchase plan purchases, and vesting of equity stock and stock units for the years ended December 31, 2016, 20152019 and 2014.December 31, 2018. Tax benefits realized as a result of employee stock option exercises, stock purchase plan purchases, and vesting of equity stock and stock units for the year ended December 31, 2017, calculated in accordance with accounting for share-based payments were $1.3 million.
Valuation Assumptions
Rambus estimates the fair value of stock options using the Black-Scholes-Merton model (“BSM”). The BSM model determines the fair value of stock-based compensation and is affected by Rambus’ stock price on the date of the grant as well as assumptions regarding a number of highly complex and subjective variables. These variables include expected volatility, expected life of the award, expected dividend rate, and expected risk-free rate of return. The assumptions for expected volatility and expected life are the two assumptions that significantly affect the grant date fair value. If actual results differ significantly from these estimates, stock-based compensation expense and Rambus’ results of operations could be materially impacted.
The fair value of stock awards is estimated as of the grant date using the BSM option-pricing model assuming a dividend yield of 0% and the additional weighted-average assumptions as listed in the following tables:

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (Continued)

The following table presents the weighted-average assumptions used to estimate the fair value of stock options granted that contain only service conditions in the periods presented.presented:
 Stock Option Plan for Years Ended December 31,
 2019 2018 2017
Stock Option Plan     
Expected stock price volatility33%-36% 24%-32% 24%-32%
Risk free interest rate1.4%-1.6% 2.6%-2.8% 1.8%-2.0%
Expected term (in years)5.1-5.2 5.8 5.3-5.4
Weighted-average fair value of stock options granted$4.36 $4.23 $4.09
 Stock Option Plans for Years Ended December 31,
 2016 2015 2014
Stock Option Plans     
Expected stock price volatility34%-36% 41% 40%-44%
Risk free interest rate1.3%-1.7% 1.2% 2.1%-2.2%
Expected term (in years)5.4-6.1 6.0 6.0-6.1
Weighted-average fair value of stock options granted$4.59 $4.59 $4.26
During the year ended December 31, 2012, the Company granted 1,795,000 stock options that contain a market condition. The fair values of the options granted with a market condition were calculated using a binomial valuation model, which estimates the potential outcome of reaching the market condition based on simulated future stock prices. The weighted average fair value associated with these market condition options was immaterial.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (Continued)


 Employee Stock Purchase Plan for Years Ended December 31,
 2019 2018 2017
Employee Stock Purchase Plan     
Expected stock price volatility32% 27%-34% 25%-27%
Risk free interest rate1.6%-2.4% 2.05%-2.5% 0.98%-1.3%
Expected term (in years)0.5 0.5 0.5
Weighted-average fair value of purchase rights granted under the purchase plan$3.13 $2.59 $3.07

 Employee Stock Purchase Plan for Years Ended December 31,
 2016 2015 2014
Employee Stock Purchase Plan     
Expected stock price volatility31%-33% 34%-42% 39%-44%
Risk free interest rate0.41%-0.5% 0.1%-0.3% 0.0%-0.1%
Expected term (in years)0.5 0.5 0.02-0.5
Weighted-average fair value of purchase rights granted under the purchase plan$2.88 $3.06 $3.57
Expected Stock Price Volatility:  Given the volume of market activity in its market traded options, Rambus determined that it would use the implied volatility of its nearest-to-the-money traded options. The Company believes that the use of implied volatility is more reflective of market conditions and a better indicator of expected volatility than historical volatility. If there is not sufficient volume in its market traded options, the Company will use an equally weighted blend of historical and implied volatility.
Risk-free Interest Rate:  Rambus bases the risk-free interest rate used in the BSM valuation method on implied yield currently available on the U.S. Treasury zero-coupon issues with an equivalent term. Where the expected terms of Rambus’ stock-based awards do not correspond with the terms for which interest rates are quoted, Rambus uses an approximation based on rates on the closest term currently available.
Expected Term:  The expected term of options granted represents the period of time that options granted are expected to be outstanding. The expected term was determined based on historical experience of similar awards, giving consideration to the contractual terms of the stock-based awards, vesting schedules and expectations of future employee behavior. The expected term of ESPP grants is based upon the length of each respective purchase period.
Nonvested Equity Stock and Stock Units
The Company grants nonvested equity stock units to officers, directors and employees. For the yearyears ended December 31, 20162019, 20152018 and 20142017, the Company granted nonvested equity stock units totaling 3,344,448, 2,865,8784,233,701, 2,978,558 and 390,5023,075,396 shares, respectively, under the 2015 Plan and the 2006 Plan.respectively. These awards have a service condition, generally a service period of four years, except in the case of grants to directors, for which the service period is one year. TheFor the years ended December 31, 2019, 2018 and 2017, the fair value of nonvested equity stock units were valued at the date of grant giving them a fair value ofwas approximately $42.9$43.0 million, $33.3$38.1 million and $4.1$40.0 million, respectively. During the first quarters of 2016years ended December 31, 2019, 2018 and 2015,2017, the Company granted performance unit awards to certain Company executive officers with vesting subject to the achievement of certain performance conditions. The ultimate number of performance units that can be earned can range from 0% to 150%200% of target depending on performance relative to target over the applicable period. The shares earned will vest on the third anniversary of the date of grant. The Company'sCompany’s shares available for grant has been reduced to reflect the shares that could be earned at 150% ofthe maximum target. During the years ended December 31, 2016 and 2015, the Company recorded $2.8 million and $1.1 million, respectively, of stock-based compensation expense related to these performance unit awards.
For the years ended December 31, 20162019, 20152018 and 20142017, the Company recorded stock-based compensation expense of approximately $15.3$23.9 million, $6.3$18.6 million and $2.8$22.9 million,, respectively, related to all outstanding nonvested equity stock grants. Unrecognized stock-based compensation related to all nonvested equity stock grants, net of an estimate of forfeitures, was approximately $37.1$33.2 million at December 31, 20162019. This cost is expected to be recognized over a weighted average period of 2.82.4 years.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (Continued)

The following table reflects the activity related to nonvested equity stock and stock units for the three years ended December 31, 20162019:

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (Continued)

Nonvested Equity Stock and Stock UnitsShares 
Weighted-Average
Grant-Date Fair Value
Nonvested at December 31, 20164,863,056 $12.33
Granted3,075,396 $13.02
Vested(1,216,476) $12.15
Forfeited(860,627) $12.61
Nonvested at December 31, 20175,861,349 $12.68
Granted2,978,558 $12.77
Vested(1,713,930) $12.39
Forfeited(2,266,842) $12.97
Nonvested at December 31, 20184,859,135 $12.71
Granted4,233,701 $10.17
Vested(1,896,283) $12.40
Forfeited(1,907,070) $11.33
Nonvested at December 31, 20195,289,483 $11.27

Nonvested Equity Stock and Stock UnitsShares 
Weighted-Average
Grant-Date Fair Value
Nonvested at December 31, 2013629,649 $8.56
Granted390,502 $10.40
Vested(262,580) $9.85
Forfeited(83,707) $7.69
Nonvested at December 31, 2014673,864 $9.23
Granted2,865,878 $11.62
Vested(276,622) $9.94
Forfeited(255,002) $10.64
Nonvested at December 31, 20153,008,118 $11.32
Granted3,344,448 $12.84
Vested(789,864) $10.98
Forfeited(699,646) $11.94
Nonvested at December 31, 20164,863,056 $12.33

13.15. Stockholders’ Equity
Share Repurchase Program
In October 2001, the Company’s Board of Directors (the “Board”) approved a share repurchase program of its common stock, principally to reduce the dilutive effect of employee stock options. Under this program, the Board approved the authorization to repurchase up to 19.0 million shares of the Company’s outstanding common stock over an undefined period of time. On February 25, 2010, the Board approved a new share repurchase program authorizing the repurchase of up to an additional 12.5 million shares. 
ForDuring the year ended December 31, 2014,2019, the Company did not repurchase any shares of its common stock under its share repurchase program. As of December 31, 2014, the Company had repurchased a cumulative total of approximately 26.3 million shares of its common stock with an aggregate price of approximately $428.9 million since the commencement of the program in 2001. As of December 31, 2014, there remained an outstanding authorization to repurchase approximately 5.2 million shares of the Company’s outstanding common stock.
On January 21, 2015, the Company'sCompany’s Board approved a new share repurchase program authorizing the repurchase of up to an aggregate of 20.0 million shares. Share repurchases under the plan may be made through the open market, established plans or privately negotiated transactions in accordance with all applicable securities laws, rules, and regulations. There is no expiration date applicable to the plan. This new stock repurchase program replaced the previous program approved by the Board in February 2010 and canceled the remaining shares outstanding as part of the previous authorization.

On October 26, 2015,March 5, 2018, the Company initiated an accelerated share repurchase program with Citibank N.A. The accelerated share repurchase program iswas part of the broader share repurchase program previously authorized by the Company'sCompany’s Board on January 21, 2015. Under the accelerated share repurchase program, the Company pre-paid to Citibank N.A., the $100.0$50.0 million purchase price for its common stock and, in turn, the Company received an initial delivery of approximately 7.83.1 million shares of its common stock from Citibank N.A,N.A., in the first quarter of 2018, which were retired and recorded as a $80.0$40.0 million reduction to stockholders'stockholders’ equity. The remaining $20.0$10.0 million of the initial payment was recorded as a reduction to stockholders’ equity as an unsettled forward contract indexed to the Company'sCompany’s stock. During the second quarter of 2018, the accelerated share repurchase program was completed and the Company received an additional 0.7 million shares of its common stock as the final settlement of the accelerated share repurchase program. There were no other repurchases of the Company’s common stock during 2018.
On May 1, 2017, the Company initiated an accelerated share repurchase program with Barclays Bank PLC. The accelerated share repurchase program was part of the broader share repurchase program previously authorized by the Company’s Board on January 21, 2015. Under the accelerated share repurchase program, the Company pre-paid to Barclays Bank PLC the $50.0 million purchase price for its common stock and, in turn, the Company received an initial delivery of approximately 3.2 million shares of its common stock from Barclays Bank PLC, in the second quarter of 2017, which were retired and recorded as a $40.0 million reduction to stockholders’ equity. The remaining $10.0 million of the initial payment was recorded as a reduction to stockholders’ equity as an unsettled forward contract indexed to the Company’s stock. The number of shares to be ultimately purchased by the Company was determined based on the volume weighted average price of the common stock during the terms of the transaction, minus an agreed upon discount between the parties. During the secondfourth quarter of 2016,2017, the

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (Continued)

accelerated share repurchase program was completed and the Company received an additional 0.70.8 million shares of its common stock as the final settlement of the accelerated share repurchase program. There were no other repurchases of the Company'sCompany’s common stock during 2016.

2017.
As of December 31, 2016,2019, there remained an outstanding authorization to repurchase approximately 11.53.6 million shares of the Company’s outstanding common stock under the current share repurchase program.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (Continued)


The Company records stock repurchases as a reduction to stockholders’ equity. The Company records a portion of the purchase price of the repurchased shares as an increase to accumulated deficit when the price of the shares repurchased exceeds the average original proceeds per share received from the issuance of common stock. During the year ended December 31, 2016,2018, the cumulative price of $17.6$37.5 million was recorded as an increase to accumulated deficit.
Convertible Note Hedge Transactions
On November 14, 2017 and November 16, 2017, in connection with the 2023 Notes, the Company entered into the Convertible Note Hedge Transactions with respect to the Common Stock, with the Counterparties. The Company paid an aggregate amount of approximately $33.5 million to the Counterparties for the Convertible Note Hedge Transactions. The Convertible Note Hedge Transactions cover, subject to anti-dilution adjustments substantially similar to those in the 2023 Notes, approximately 9.1 million shares of Common Stock, the same number of shares underlying the 2023 Notes, at a strike price that corresponds to the initial conversion price of the 2023 Notes, and are exercisable upon conversion of the 2023 Notes. The Convertible Note Hedge Transactions will expire upon the maturity of the 2023 Notes.
The Convertible Note Hedge Transactions are expected generally to reduce the potential dilution to the Common Stock upon conversion of the 2023 Notes and/or offset any cash payments the Company is required to make in excess of the principal amount of the converted 2023 Notes, as the case may be, in the event that the market price per share of the Common Stock, as measured under the terms of the Convertible Note Hedge Transactions, is greater than the strike price of the Convertible Note Hedge Transactions.
The Convertible Note Hedge Transactions are separate transactions, entered into by the Company with the Counterparties, and are not part of the terms of the 2023 Notes. Holders of the 2023 Notes will not have any rights with respect to the Convertible Note Hedge Transactions. Refer to Note 12, “Convertible Notes,” for additional details.
Warrant Transactions
On November 14, 2017 and November 16, 2017, in connection with the 2023 Notes, the Company sold the Warrants to the Counterparties to acquire, collectively, subject to anti-dilution adjustments, approximately 9.1 million shares of the Common Stock at an initial strike price of approximately $23.30 per share, which represents a premium of 60% over the last reported sale price of the Common Stock of $14.56 on November 14, 2017. The Company received aggregate proceeds of approximately $23.2 million from the sale of the Warrants to the Counterparties. The Warrants were sold in private placements to the Counterparties pursuant to an exemption from the registration requirements of the Securities Act afforded by Section 4(a)(2) of the Securities Act.
If the market price per share of the Common Stock, as measured under the terms of the Warrants, exceeds the strike price of the Warrants, the Warrants could have a dilutive effect, unless the Company elects, subject to certain conditions, to settle the Warrants in cash.
The Warrants are separate transactions, entered into by the Company with the Counterparties, and are not part of the terms of the 2023 Notes. Holders of the 2023 Notes will not have any rights with respect to the Warrants. Refer to Note 12, “Convertible Notes,” for additional details.

14.16. Benefit Plans
Rambus has a 401(k) Profit Sharing Plan (the “401(k) Plan”) qualified under Section 401(k) of the Internal Revenue Code of 1986. Each eligible employee may elect to contribute up to 60% of the employee’s annual compensation to the 401(k) Plan, up to the Internal Revenue Service limit. Rambus, at the discretion of its Board of Directors, may match employee contributions to the 401(k) Plan. The Company matches 50% of eligible employee’s contribution, up to the first 6% of an eligible employee’s qualified earnings. For the years ended December 31, 20162019, 20152018 and 20142017, Rambus made matching contributions totaling approximately $2.0$2.0 million,, $2.1 million and $1.92.3 million, respectively.



15.17. Divestiture
During the second quarter of 2019, the Company entered into a share purchase agreement with Visa International Service Association (the “Purchaser”), pursuant to which the Purchaser agreed to acquire all of the outstanding shares of the Company’s subsidiary, Smart Card Software Limited, which comprises the Company’s Payments and Ticketing businesses, which was part of the Company’s former Rambus Security Division (RSD) segment. The decision to sell these businesses reflected the Company’s ongoing review of its business to focus on products and offerings that are core to its semiconductor business.
The sale of the legal entities comprising the Company’s Payments and Ticketing businesses was completed in October 2019. The final gross proceeds from the sale amounted to $82.5 million, which included the selling price of $75.0 million and approximately $7.5 million in net working capital adjustments finalized in October 2019. The $7.5 million in net working capital adjustments is net of a final working capital adjustment due to the buyer of approximately $1.1 million, which the Company will pay in cash to the buyer during the first quarter of 2020. The final gross proceeds were offset by approximately $3.8 million in transaction costs for the year ended December 31, 2019.
The Company measured these businesses at the lower of their carrying value or fair value less any costs to sell, and recognized a cumulative impairment of approximately $7.4 million during the year ended December 31, 2019. In the second quarter of 2019, in order to determine the impairment loss, the Company performed a relative fair value measurement to allocate goodwill to the business units between the disposed Payments and Ticketing businesses and the retained business, which includes Cryptography Research Inc., which was part of the former RSD segment. The fair value of the retained business was estimated by management using a discounted cash flow model. The Company’s cash flow projections for the retained business included significant judgments and assumptions relating to revenue growth rates, projected operating income and the discount rate.
The operating results of these businesses did not qualify for reporting as discontinued operations. The reported results and financial position of the businesses did not necessarily reflect the total value of the businesses that the Company realized upon their sale.

18. Restructuring and Other Charges
The 20152019 Plan
During 2015,In June 2019, the Company initiated a restructuring program to reduce overall corporate expenses which is expected to improve future profitability by reducing spending on research and development efforts and sales, general and administrative programs and refining some of its research and development efforts ("the 2015 Plan"(the “2019 Plan”). In connection with this restructuring program, the Company initiated a plan of termination resulting in a reduction of 8% of the Company's headcount. The Company estimated that it would incur a cash payout related to the reduction in force of approximately $3.0 million, which is related to severance and termination benefits. The estimated non-cash expense was expected to be approximately $1.0 million.80 employees. During the year ended December 31, 2015,2019, the Company recorded a chargerestructuring and other severance-related charges of $3.6approximately $8.8 million related primarily to the reduction in workforce. As of December 31, 2019, the Company’s accrued restructuring balance was approximately $5.0 million. The 2019 Plan is expected to be substantially completed in early 2020.
The 2018 Plan
On January 30, 2018, the Company announced its plans to close its lighting division and manufacturing operations in Brecksville, Ohio, (“the 2018 Plan”). The Company believed that such business was not core to its strategy and growth objectives. In connection therewith, the Company terminated approximately 50 employees, and began the process to exit the facilities in Ohio and sell the related equipment. The Company expected to record restructuring charges of approximately $2.0 million to $5.0 million related to employee terminations and severance costs and facility related costs. During the year ended December 31, 2018, the Company recorded a net charge of $2.2 million, primarily related to the reduction in workforce, of which $1.4$2.0 million was related to the MID reportable segment, $0.1 million was related to the RSD reportable segment, $1.2 million was related to the Other segmentlighting division and $0.9$0.2 million was related to corporate support functions. The 20152018 Plan was completed in 2016.as of December 31, 2019.
The following table summarizesCompany concluded that the 2015 Plan restructuring activities duringclosure of its lighting division did not meet the years endedcriteria for reporting as discontinued operations. Consequently, the lighting division’s long-lived assets were reclassified as held for sale. As of December 31, 20162018, the Company sold all property, plant and 2015:
  
Employee
Severance
and Related Benefits
 Facilities Total
  (In thousands)
Balance at December 31, 2014 $
 $
 $
Charges 2,993
 583
 3,576
Payments (1,765) 
 (1,765)
Non-cash settlements 
 (583)*(583)
Balance at December 31, 2015 $1,228
 $
 $1,228
Payments (1,228) 
 (1,228)
Balance at December 31, 2016 $
 $
 $

*The non-cash chargeequipment from its lighting division reclassified as held for sale on the consolidated balance sheets of $583 thousand is related toapproximately $3.5 million and recognized a gain on the write downdisposal of fixedthe held for sale assets related toof approximately $1.2 million included in restructuring charges on the Other segment.
consolidated statements of operations.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (Continued)


16.During 2017, the Company did not initiate any restructuring programs.

19. Income Taxes
Income (loss) before taxes consisted of the following:
Years Ended December 31,Years Ended December 31,
2016 2015 20142019 2018 2017
(In thousands)(In thousands)
Domestic$38,211
 $58,498
 $49,173
$(81,316) $(63,829) $46,031
Foreign(15,574) 1,733
 1,077
(5,700) (6,799) (5,042)
$22,637
 $60,231
 $50,250
$(87,016) $(70,628) $40,989

The provision for (benefit from) income taxes is comprised of:
Years Ended December 31,Years Ended December 31,
2016 2015 20142019 2018 2017
(In thousands)(In thousands)
Federal:          
Current$22,115
 $20,497
 $19,386
$2,932
 $5,451
 $20,661
Deferred(2,198) (170,798) 2,337
2,016
 82,726
 43,678
State:          
Current884
 609
 713
657
 333
 495
Deferred(271) (1,933) 
(1,198) 522
 (43)
Foreign:          
Current1,275
 443
 1,640
1,708
 1,592
 1,101
Deferred(5,988) 25
 (27)(2,712) (3,295) (2,041)
$15,817
 $(151,157) $24,049
$3,403
 $87,329
 $63,851

The differences between Rambus’ effective tax rate and the U.S. federal statutory regular tax rate are as follows:
Years Ended December 31,Years Ended December 31,
2016 2015 20142019 2018 2017
Expense at U.S. federal statutory rate35.0 % 35.0 % 35.0 %21.0 % 21.0 % 35.0 %
Expense (benefit) at state statutory rate1.8
 (1.5) 1.0
0.9
 (1.2) 0.7
Withholding tax97.0
 34.1
 38.6
(3.5) (7.7) 50.1
Foreign rate differential4.1
 0.4
 2.5
(1.1) (0.2) 2.8
Research and development (“R&D”) credit(8.3) (2.3) (6.1)1.2
 2.2
 (3.9)
Executive compensation1.5
 0.5
 0.2
(1.2) (0.1) 1.8
Stock-based compensation34.8
 5.3
 1.4
(2.3) (2.8) 14.9
Foreign tax credit(97.0) (34.1) (38.7)3.4
 7.7
 (50.1)
Foreign derived intangible income deduction4.6
 14.8
 
Impact of corporate rate change on deferred taxes
 
 50.6
Divestiture4.8
 
 
Other1.0
 (0.6) 0.6
(0.2) 0.7
 1.4
Valuation allowance
 (287.8) 13.4
(31.5) (158.0) 52.5
69.9 % (251.0)% 47.9 %(3.9)% (123.6)% 155.8 %


NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (Continued)


The components of the net deferred tax assets (liabilities) are as follows:
 As of December 31,
 2016 2015
 (In thousands)
Deferred tax assets:   
Depreciation and amortization$22,174
 $30,019
Other liabilities and reserves12,442 7,227
Deferred equity compensation17,426 23,176
Net operating loss carryovers11,439 11,746
Tax credits120,660 117,078
Total gross deferred tax assets184,141
 189,246
Convertible debt(3,870) (6,044)
Total net deferred tax assets180,271
 183,202
Valuation allowance(23,529) (20,717)
Net deferred tax assets$156,742
 $162,485
 As of December 31,
 2016 2015
 (In thousands)
Reported as:   
Non-current deferred tax assets$168,342
 $162,485
Non-current deferred tax liabilities(11,600) 
Net deferred tax assets$156,742
 $162,485
 As of December 31,
 2019 2018
 (In thousands)
Deferred tax assets:   
Depreciation and amortization$13,995
 $13,085
Lease liabilities10,734 
Other timing differences, accruals and reserves9,522 8,272
Deferred equity compensation4,456 6,236
Net operating loss carryovers20,900 21,259
Tax credits233,407 253,890
Total gross deferred tax assets293,014
 302,742
Deferred tax liabilities:   
Lease right-of-use assets(10,400) 
Convertible debt(151) (207)
Deferred revenue(94,763) (143,182)
Total gross deferred tax liabilities(105,314) (143,389)
Total net deferred tax assets187,700
 159,353
Valuation allowance(196,972) (173,878)
Net deferred tax liabilities$(9,272) $(14,525)
In November 2015, the FASB issued ASU No. 2015-17, "Balance Sheet Classification of Deferred Taxes (Topic 740)," to simplify the presentation of deferred income taxes. The amendments in this update require that deferred tax liabilities and assets be classified as non-current in a classified statement of financial position. This ASU is effective for financial statements issued for fiscal years beginning after December 15, 2016 and interim periods within those fiscal years. Early adoption is permitted.
 As of December 31,
 2019 2018
 (In thousands)
Reported as:   
Non-current deferred tax assets$4,574
 $4,435
Non-current deferred tax liabilities(13,846) (18,960)
Net deferred tax liabilities$(9,272) $(14,525)

The Company has early adopted this ASU as of December 31, 2015 on a prospective basis.
Management periodically evaluates the realizability of its net deferred tax assets based on all available evidence, both positive and negative. The realizabilityDuring the third quarter of 2018, the Company’s net deferred tax assets is dependent onCompany assessed the changes in its ability to generate sufficient future taxable income during periods prior to the expiration of tax attributes to fully utilize these assets. Managementunderlying facts and circumstances and evaluated the realizability of its netexisting deferred tax assets based on all available evidence, both positive and negative, in determining that it was appropriate to release the valuation allowance for the Company’s U.S. federal and other state deferred tax assets of $174.5 million during the third quarter of 2015 in accordance with FASB ASC 740-10-30-16 to 25.
The Company emerged from a cumulative loss position over the previous three years during the first quarter of 2015. The cumulative three-year pre-tax income is considered positive evidence which is objective and verifiable, and thus, received significant weighting. The continued stability in the Company’s operations along with the increased visibility into the adoption of its security technology in the third quarter of 2015 provided additional evidence to the Company’s belief that it will generate sufficient taxable income in the future. Additional positive evidence considered by management in its assessment included a lack of unused operating loss carryforwards in the Company’s history as well as anticipated future benefits from its cost management. Negative evidence management considered included economic uncertainties such as volatility of the semiconductor industry and uncertainties associated with the development of new products that could impact the Company’s ability to generate a sustained level of future profits.
Upon considering the relative impact of all evidence during the third quarter of 2015, both negative and positive, and the weight accorded to each, the Companyand concluded that it was more likely than not that its deferred tax assets would be realizablea full valuation allowance associated with the exception of primarily itsU.S. federal and California deferred tax assets that have not met the “more likely than not” realization threshold criteria.was appropriate. As a result,such, the Company released the related valuation allowance against such deferred tax assets which is included as a component of the benefit from income taxes in the accompanying consolidated statement of operations. The Companyhas set up and continues to maintain a full valuation allowance against its U.S. federal deferred tax asset valuation allowance of $23.5 million as of December 31, 2016.assets.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (Continued)


The following table presents the tax valuation allowance information for the years ended December 31, 20162019, 20152018 and 2014:2017:
 Balance at Beginning of Period Charged (Credited) to Operations Charged to Other Account* Valuation Allowance Release Balance at End of Period
Tax Valuation Allowance         
Year ended December 31, 2014$192,823
 
 1,051
 
 $193,874
Year ended December 31, 2015$193,874
 
 1,299
 (174,456) $20,717
Year ended December 31, 2016$20,717
 
 2,812
 
 $23,529
 Balance at Beginning of Period Charged (Credited) to Operations Charged to Other Account* Valuation Allowance Release Valuation Allowance Set up Balance at End of Period
Tax Valuation Allowance           
Year ended December 31, 2017$23,529
 
 5,855
 
 21,527
 $50,911
Year ended December 31, 2018$50,911
 
 9,238
 
 113,729
 $173,878
Year ended December 31, 2019$173,878
 23,094
 
 
 
 $196,972

*Amounts not charged to operations are charged to other comprehensive income or deferred tax assets (liabilities).retained earnings.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (Continued)

As of December 31, 20162019, Rambus had California and other state net operating loss carryforwards of $274.6$202.7 million and $99.7$36.4 million, respectively. As of December 31, 20162019, Rambus had federal and state capital loss carryforwards of $26.4 million. As of December 31, 2019, Rambus had federal research and development tax credit carryforwards of $36.5$40.6 million,, alternative minimum tax creditscredit carryforwards of $2.5$1.9 million and foreign tax credits of $120.3$186.1 million. As of December 31, 2016,2019, Rambus had California research and development tax credit carryforwards of $24.7 million. These carryforward amounts included $38.2 million of federal tax credits and $98.2 million of California net operating losses for which no deferred tax asset has been recognized because they relate to excess tax benefits from stock-based compensation tax deductions. The excess tax benefits will be recorded to additional paid-in capital when they reduce cash taxes payable.$31.5 million. The federal foreign tax credits and research and development credits begin to expire in 2020 and 2018,2019, respectively. Approximately $55$29.1 million of federal foreign tax credits will expire in 2020. The California net operating losses beganbegin to expire in 2016, and $3.2 million expired during the year. Additionally, $64.5 million of California net operating loss is expected to expire in 2017.2020. The federal alternative minimum tax credits and the California research and development credits carry forward indefinitely.
In the event of a change in ownership, as defined under federal and state tax laws, Rambus'Rambus’ net operating loss and tax credit carryforwards could be subject to annual limitations. The annual limitations could result in the expiration of the net operating loss and tax credit carryforwards prior to utilization.
As of December 31, 20162019, the Company had $21.9$115.7 million of unrecognized tax benefits including $19.7$22.8 million recorded as a reduction of long-term deferred tax assets, and $2.2$91 million recorded in long term income taxes payable. If recognized, $2.2 million would be recorded as an income tax benefit in the consolidated statements of operations. As of December 31, 2015, the Company had $20.8 million of unrecognized tax benefits including $18.6 million recorded as a reduction of long-term deferred taxother assets associated with refundable withholding taxes previously withheld from licensees in South Korea (Korea), and $2.2$1.8 million recorded in long termlong-term income taxes payable. As a result of recent court rulings in Korea, the Company has determined that they may be entitled to refund claims for foreign taxes previously withheld from licensees in Korea. The Company recognizes that there are numerous risks and uncertainties associated with the ultimate collection of this refund, and, has therefore established an offsetting reserve for the entire amount of refundable withholding taxes previously withheld in Korea (which had an insignificant impact to the Company’s income tax provision). If recognized, $2.2$1.8 million would be recorded as an income tax benefit in the consolidated statementsstatement of operations. As of December 31, 2018, the Company had $23.5 million of unrecognized tax benefits including $21.4 million recorded as a reduction of long-term deferred tax assets and $2.1 million recorded in long term income taxes payable. If recognized, $2.1 million would be recorded as an income tax benefit in the consolidated statement of operations. It is reasonably possible that a reduction of up to $0.2$0.1 million of existing unrecognized tax benefits could occur in the next 12 months.
A reconciliation of the beginning and ending amounts of unrecognized income tax benefits for the years ended December 31, 20162019, 20152018 and 20142017 is as follows (amounts in thousands):
 Years Ended December 31,
 2019 2018 2017
Balance at January 1$23,482
 $22,652
 $21,925
Tax positions related to current year:     
Additions16,485
 1,032
 1,083
Tax positions related to prior years:     
Additions76,158
 115
 16
Reductions(472) (317) (372)
Settlements
 
 
Balance at December 31$115,653
 $23,482
 $22,652

 Years Ended December 31,
 2016 2015 2014
Balance at January 1$20,836
 $19,903
 $18,794
Tax positions related to current year:     
Additions1,225
 1,186
 1,134
Tax positions related to prior years:     
Additions256
 
 531
Reductions(171) (35) (556)
Settlements(221) (218) 
Balance at December 31$21,925
 $20,836
 $19,903

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (Continued)

Rambus recognizes interest and penalties related to uncertain tax positions as a component of the income tax provision (benefit). At December 31, 20162019 and 20152018, an immaterial amount of interest and penalties are included in long-term income taxes payable.
Rambus files income tax returns for the U.S., California, India, the U.K., the Netherlands and various other state and foreign jurisdictions. The U.S. federal returns are subject to examination from 20132016 and forward. The California returns are subject to examination from 2010 and forward. In addition, any R&Dresearch and development credit carryforward or net operating loss carryforward generated in prior years and utilized in these or future years may also be subject to examination. The India returns are subject to examination from fiscal year ending March 2012 and forward. The Company is currently under examination by California for the 2010 and 2011 tax years. The Company’s India subsidiary is under examination by the Indian tax administration for tax years beginning with 2011, except for 2014, which was assessed in the Company'sCompany’s favor. These examinations may result in proposed adjustments to the income taxes as filed during these periods. Management regularly assesses the likelihood of outcomes resulting from income tax examinations to determine the adequacy of their provision for income taxes and believes their provision for unrecognized tax benefits is adequate.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (Continued)

Additionally, the Company’s future effective tax rates could be adversely affected by earnings being higher than anticipated in countries where the Company has higher statutory rates or lower than anticipated in countries where it has lower statutory rates, by changes in valuation of its deferred tax assets and liabilities or by changes in tax laws or interpretations of those laws.
At December 31, 2016,2019, no deferredother income taxes (state or foreign) have been provided on undistributed earnings of approximately $6.7$14.0 million from the Company’s international subsidiaries since these earnings have been, and under current plans will continue to be, indefinitely reinvested outside the United States. It is not practicable to determineHowever, if such earnings were distributed, the Company would incur approximately $1.9 million of foreign withholding taxes and an immaterial amount of the unrecognized tax liability at this time.U.S. taxes.
17.20. Litigation and Asserted Claims
Rambus is not currently a party to any material pending legal proceeding; however, from time to time, Rambus may become involved in legal proceedings or be subject to claims arising in the ordinary course of its business. Although the results of litigation and claims cannot be predicted with certainty, the Company currently believes that the final outcome of these ordinary course matters will not have a material adverse effect on our business, operating results, financial position or cash flows. Regardless of the outcome, litigation can have an adverse impact on the Company because of defense and settlement costs, diversion of management attention and resources and other factors.


The Company records a contingent liability when it is probable that a loss has been incurred and the amount is reasonably estimable in accordance with accounting for contingencies.
18. Agreements with SK hynix and Micron
SK hynix
On June 11, 2013, Rambus, SK hynix and certain related entities of SK hynix entered into a settlement agreement, pursuant to which the parties have agreed to release all claims against each other with respect to all outstanding litigation between them. Pursuant to the settlement agreement, Rambus and SK hynix entered into a semiconductor patent license agreement on June 11, 2013, under which SK hynix licenses from Rambus non-exclusive rights to certain Rambus patents and has agreed to pay Rambus cash amounts over the next five years. Under the license agreement, Rambus has granted to SK hynix (i) a paid-up perpetual patent license for certain identified SK hynix DRAM products and (ii) a five-year term patent license to all other DRAM and other semiconductor products.

In June 2015, the Company signed an amendment that extends its current agreement with SK hynix for an additional six years for use of Rambus memory-related patented innovations in SK hynix semiconductor products. The Company signed the original agreement with SK hynix for a five-year term in June 2013. Under the amendment, SK hynix has agreed to continue to pay the Company an average quarterly cash payment of $12.0 million which equates to $432.0 million from the signing of the amendment through the term of the agreement ending July 1, 2024, provided that (a) for each of the six full calendar quarters immediately following July 1, 2015, SK hynix will pay the Company a quarterly cash payment of $16.0 million, and (b) in addition, after December 1, 2017, SK hynix will have the option to make six quarterly cash payments of $8.0 million upon six months written notice. In addition, SK hynix has the option to renew the agreement for an additional three-year extension under the existing rate structure.

The agreements with SK hynix are considered a multiple element arrangement for accounting purposes. For a multiple element arrangement under the applicable accounting rules, the Company is required to identify specific elements of the arrangement and then determine when those elements should be recognized. The Company identified three elements in the arrangement: antitrust litigation settlement, settlement of past infringement, and license agreement. The Company considered

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (Continued)

several factors in determining the accounting fair value of the elements of the SK hynix agreements which included a third party valuation using an income approach (collectively the “SK hynix Fair Value”). The inputs and assumptions used in this accounting valuation were from a market participant perspective and included projected customer revenue, royalty rates, estimated discount rates, useful lives and income tax rates, among others. The development of a number of these inputs and assumptions in the model requires a significant amount of management judgment and discretion, and is based upon a number of factors, including the selection of industry comparables, market growth rates and other relevant factors. Changes in any number of these assumptions may have a substantial impact on the SK hynix Fair Value as assigned to each element. These inputs and assumptions represent management’s best estimates at the time of the transaction. The following estimates do not reflect any agreement (expressed or implied) reached between the parties on the values attributed to any aspect of this transaction. The estimated SK hynix Fair Value is determined as follows:
(in millions)Estimated SK hynix Fair Value
Antitrust litigation settlement$4.0
Settlement of past infringement280.0
License agreement250.0
Total SK hynix Fair Value$534.0

The total original consideration of $240.0 million (as per the terms of the agreements with SK hynix) takes into account the court ruling in May 2013 that $250.0 million should be applied as a credit against the court’s March 2009 award to Rambus in the SK hynix litigation. Using the accounting guidance from multiple element revenue arrangements, the Company allocated the consideration to each element using the estimated SK hynix Fair Value of the elements which include antitrust litigation settlement, settlement of past infringement, and license agreement as shown in the table above. The following allocations do not reflect any agreement (expressed or implied) reached between the parties on the values attributed to any aspect of this transaction, but instead, reflect only what is required as disclosure under the applicable accounting rules. Based on the estimated SK hynix Fair Value, the total consideration of $240.0 million was allocated to the following elements:
(in millions)Allocated Consideration
Antitrust litigation settlement$1.9
Settlement of past infringement125.8
License agreement112.3
Total original consideration$240.0

The consideration of $528.0 million (including the impact of the June 2015 amendment to the agreement and assuming no adjustments to the payments under the terms of the agreements) will be recognized in the Company’s financial statements until 2024 as follows:

·$526.1 million as "royalty revenue" which represents the allocated consideration related to the settlement of past infringement ($125.8 million) from the resolution of the infringement litigation and the patent license agreement ($400.3 million); and
·$1.9 million as "gain from settlement" which represents the allocated consideration related to the resolution of the antitrust litigation.

During the years ended December 31, 2016 and 2015, the Company received cash consideration of $64.0 million and $56.0 million, respectively, from SK hynix. The amounts were allocated between royalty revenue ($63.9 million in 2016 and $55.3 million in 2015) and gain from settlement ($0.1 million in 2016 and $0.7 million in 2015) based on the elements’ SK hynix Fair Value.


NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (Continued)

The cash receipts and remaining future cash receipts from the agreements with SK hynix are expected to be recognized as follows assuming no adjustments to the payments under the terms of the agreements (and assuming the option to make the lower payments begins with payments made during the middle of 2018):
 
Received
 in
 Estimated to Be Received in 
Total Estimated
Cash Receipts
 2013 2014 2015 2016 2017 2018 2019 2020 2021 and thereafter 
(in millions)                   
Royalty revenue$23.6
 $47.3
 $55.3
 $63.9
 $48.0
 $40.0
 $32.0
 $48.0
 $168.0
 $526.1
Gain from settlement0.4
 0.7
 0.7
 0.1
 
 
 
 
 
 1.9
Total$24.0
 $48.0
 $56.0
 $64.0
 $48.0
 $40.0
 $32.0
 $48.0
 $168.0
 $528.0

Micron
On December 9, 2013, Rambus, Micron and certain related entities of Micron entered into a settlement agreement, pursuant to which the parties have agreed that they will release all claims against each other with respect to all outstanding litigation between them and certain other potential claims. Pursuant to the settlement agreement, Rambus and Micron entered into a semiconductor patent license agreement on December 9, 2013. Under the license agreement, Rambus has granted to Micron and its subsidiaries and certain affiliated entities (i) a paid-up perpetual patent license for certain identified Micron DRAM products and (ii) a seven-year term patent license to other memory and semiconductor products.

The agreements with Micron are considered a multiple element arrangement for accounting purposes. For a multiple element arrangement under the applicable accounting rules, the Company is required to identify specific elements of the arrangement and then determine when those elements should be recognized. The Company identified three elements in the arrangement: antitrust litigation settlement, settlement of past infringement, and license agreement. The Company considered several factors in determining the accounting fair value of the elements of the Micron agreements which included a third party valuation using an income approach (collectively the “Micron Fair Value”). The inputs and assumptions used in this accounting valuation were from a market participant perspective and included projected customer revenue, royalty rates, estimated discount rates, useful lives and income tax rates, among others. The development of a number of these inputs and assumptions in the model requires a significant amount of management judgment and discretion, and is based upon a number of factors, including the selection of industry comparables, market growth rates and other relevant factors. Changes in any number of these assumptions may have a substantial impact on the Micron Fair Value as assigned to each element. These inputs and assumptions represent management’s best estimates at the time of the transaction. The following estimates do not reflect any agreement (expressed or implied) reached between the parties on the values attributed to any aspect of this transaction. The estimated Micron Fair Value is determined as follows:
(in millions)Estimated Micron Fair Value
Antitrust litigation settlement$8.0
Settlement of past infringement235.0
License agreement440.0
Total Micron Fair Value$683.0

The total consideration of $280.0 million (as per the terms of the agreements with Micron) takes into account the court ruling in January 2013 that Rambus' patents-in-suit are unenforceable against Micron in the Micron litigation, but which was pending appeal at the time of settlement. Using the accounting guidance from multiple element revenue arrangements, the Company allocated the consideration to each element using the estimated Micron Fair Value of the elements which include antitrust litigation settlement, settlement of past infringement, and license agreement as shown in the table above. The following allocations do not reflect any agreement (expressed or implied) reached between the parties on the values attributed to any aspect of this transaction, but instead, reflect only what is required as disclosure under the applicable accounting rules. Based on the estimated Micron Fair Value, the total consideration of $280.0 million was allocated to the following elements:

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (Continued)

(in millions)Allocated Consideration
Antitrust litigation settlement$3.3
Settlement of past infringement96.3
License agreement180.4
Total consideration$280.0

The consideration of $280.0 million (assuming no adjustments to the payments under the terms of the agreements) will be recognized in the Company’s financial statements until 2020 as follows:

·$276.7 million as "royalty revenue" which represents the allocated consideration related to the settlement of past infringement ($96.3 million) from the resolution of the infringement litigation and the patent license agreement ($180.4 million); and
·$3.3 million as "gain from settlement" which represents the allocated consideration related to the resolution of the antitrust litigation.

During the years ended December 31, 2016 and 2015, the Company received cash consideration of $40.0 million and $40.0 million, respectively, from Micron. The amounts were allocated between royalty revenue ($39.5 million in 2016 and $38.7 million in 2015) and gain from settlement ($0.5 million in 2016 and $1.3 million in 2015) based on the elements’ Micron Fair Value.

The remaining $154.5 million is expected to be paid in successive quarterly payments of $10.0 million, concluding in the fourth quarter of 2020.

The cash receipts and remaining future cash receipts from the agreements with Micron are expected to be recognized as follows assuming no adjustments to the payments under the terms of the agreements:
 
Received
 in
 Estimated to Be Received in 
Total Estimated
Cash Receipts
 2013 2014 2015 2016 2017 2018 2019 2020 
(in millions)                 
Royalty revenue$5.3
 $38.7
 $38.7
 $39.5
 $40.0
 $40.0
 $40.0
 $34.5
 $276.7
Gain from settlement0.2
 1.3
 1.3
 0.5
 
 
 
 
 3.3
Total$5.5
 $40.0
 $40.0
 $40.0
 $40.0
 $40.0
 $40.0
 $34.5
 $280.0


19.21. Acquisitions
Smart Card Software Ltd.Northwest Logic, Inc.
On January 25, 2016,July 26, 2019, the Company entered into an Agreement and Plan of Merger (the “Merger Agreement”) with Northwest Logic, a leading supplier of memory, PCIe, and MIPI digital controllers. On August 23, 2019 (the “Closing Date”), the Company completed its acquisition of Smart Card Software Ltd. (“SCS”), a privately-held company incorporated in the United Kingdom,Northwest Logic by acquiring all issued and outstanding shares of capital stock of SCS. Pursuant toNorthwest Logic through the merger agreement on January 25, 2016, SCS was merged intoof a wholly-owned Rambus Inc. The transaction was denominated in British pounds.subsidiary with Northwest Logic. Under the terms of the merger agreement,Merger Agreement, the total consideration in U.S. dollar equivalent was $104.7 million which included the purchase price of $92.6 millionCompany paid on January 25, 2016 and additional purchase consideration to be paid in the fourth quarter of 2016 originally totaling $12.1 million and comprised of $11.6approximately $21.9 million in cash, $4.0 million inincluding certain bonus payments and adjustments for working capital, offset by $3.5 million in liabilities assumed from SCS. Subsequently, the additional purchase consideration, ultimately amounting to $10.2 million was paid in the fourth quarter of 2016.capital. Of the purchase price, approximately $17.1$3.0 million of the consideration was deposited into an escrow account to fund indemnification obligations and other contractual provisions, to be released 24 months after the Closing Date. This acquisition allows the Company to further scale, bringing together high-speed design expertise with releases of portions of the escrow at various intervals through 18 months. SCS is a leader in mobile paymentsphysical and a leading supplier of smart ticketing systems, which includes Bell Identification Ltd.digital IP families from renowned market leaders to offer comprehensive memory and Ecebs Ltd. SCS isSerDes IP solutions for chip designers. The Company integrated Northwest Logic’s offerings and design team into its IP cores technology solutions.
As part of the RSD reporting unit. This acquisition, will complement the Company's RSD reporting unit by allowing the Company agreed to leverage its foundational security technologypay $9.0 million to offer differentiated, value-added security solutionscertain Northwest Logic employees in cash over three years following August 23, 2019 (the “Retention Bonus”). The Retention Bonus will be paid in three installments of $3.0 million on each of the dates that are 12 months, 24 months and 36 months following the Closing Date. The Retention Bonus payouts are subject to its customers. During the year endedcondition of continued employment, and therefore treated as compensation and expensed as incurred.
As of December 31, 2016,2019, the Company had incurred approximately $2.0$0.7 million in external acquisition costs in connection with the acquisitiontransaction, which were expensed as incurred.
The purchase price allocation and related accounting for this acquisition is preliminary. The preliminary fair value estimates for the assets acquired and liabilities assumed were based upon preliminary calculations and valuations and the Company’s estimates and assumptions for the acquisition are subject to change if the Company obtains additional information during the measurement period. In accordance with ASC No. 805, during the measurement period an acquirer shall retrospectively adjust the provisional amounts recognized at the acquisition date to reflect information obtained about facts and circumstances that existed as of the acquisition date that, if known, would have affected the measurement of the amounts recognized as of the acquisition date. Accordingly, the Company has recognized a measurement period adjustment made during the fourth quarter of 2019 to the fair value of certain assets acquired and liabilities assumed as a result of further refinements in the Company’s estimates. This adjustment was retrospectively applied to the August 23, 2019 acquisition date balance sheet. The effect of this adjustment on the preliminary purchase price allocation was an increase in goodwill of $2.1 million and an increase in deferred tax liability, net, of $2.1 million. This adjustment did not have a material impact on the Company’s previously reported results of operations.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (Continued)


The fair value of the assets acquired has beenwas determined by management primarily by using valuation methods that discount the expected futuremulti-period excess earnings method under the income approach. This method reflects the present value of the projected cash flows that are expected to present value using estimates and assumptions determinedbe generated by management.the existing technologies less charges representing the contribution of other assets to those cash flows. The Company performed a valuation of the net assets acquired as of the January 25, 2016 closing date. Closing Date.
The total consideration from the business combination was allocated as of the Closing Date, including the retrospective adjustment made in the fourth quarter of 2019, as follows:
 Total
 (in thousands)
Cash and cash equivalents$159
Accounts receivable1,679
Prepaid expenses and other current assets65
Identified intangible assets8,800
Goodwill13,477
Operating lease right-of-use asset178
Other asset9
Accounts payable(9)
Operating lease liability(178)
Other current liabilities(108)
Deferred tax liability, net(2,133)
Total$21,939
 Total
 (in thousands)
Cash$12,056
Accounts receivable6,563
Property and equipment524
Other tangible assets1,462
Identified intangible assets59,700
Goodwill46,903
Accounts payable and accrued liabilities(5,996)
Deferred income taxes(15,556)
Deferred revenue(1,313)
Total$104,343


The goodwill arising from the acquisition is primarily attributed to synergies related to the combination of new and complementary technologies of the Company and the assembled workforce of SCS.Northwest Logic. This goodwill is not expected to be deductible for tax purposes.
The identified intangible assets assumed in the acquisition of SCSNorthwest Logic were recognized as follows based upon their estimated fair values as of the acquisition date:
Total Estimated Weighted Average Useful LifeTotal Estimated Weighted Average Useful Life
(in thousands) (in years)(in thousands) (in years)
Existing technology$24,600
 6$8,100
 5
Customer contracts and contractual relationships (1)35,100
 6400
 2
Customer backlog300
 0.5
Total$59,700
 $8,800
 

(1) Includes favorable contracts of $8.3 million with an estimated useful life of 5 years. The favorable contracts are acquired softwareSecure Silicon IP and service agreements whereProtocols Business from Verimatrix
On September 11, 2019, the Company has no performance obligations. Cash receivedannounced it had signed an asset purchase agreement to acquire the Secure Silicon IP and Protocols business from these acquired favorable contracts reduces the favorable contract intangible asset.

Inphi Memory Interconnect Business
Verimatrix, formerly Inside Secure, for $65.0 million in cash. On August 4, 2016,December 8, 2019 (the “Closing Date”), the Company completed its acquisition of all the assetsSecure Silicon IP and Protocols business. Under the terms of Inphi's Memory Interconnect Business (“Memory Interconnect Business”) from Inphi Corporation for $90the Asset Purchase Agreement, as amended, the Company paid approximately $45.0 million in cash. The acquisition includes all assetscash at the Closing Date, and will pay up to an additional $20.0 million, currently valued at $1.8 million, subject to certain revenue targets of the Memory Interconnect Business including product inventory, customer contracts, supply chain agreements and intellectual property. Oftransferred business for the purchase price, approximately $11.3 millioncalendar year 2020. The addition of the embedded security teams, products and expertise from the Secure Silicon IP and Protocols business augments the Company’s portfolio of mission-critical embedded security products and expands its offerings for data center, AI, networking and automotive.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (Continued)

The total adjusted purchase consideration for the acquisition of the Secure Silicon IP and Protocols business was deposited into an escrow account to fund indemnification obligations and other contractual provisions, to be released 12 months after$46.8 million, which consisted of the closing date. Thisfollowing:
 Total
 (in thousands)
Cash consideration transferred at the Closing Date$45,000
Fair value of earn-out liability1,800
Total adjusted purchase price$46,800

As part of the acquisition, will complement the MID reporting unit by allowing the Company agreed to strengthen its market position for memory buffer chip productspay $1.0 million to certain employees in cash over two years effective January 1, 2020 (the “Retention Bonus”). The Retention Bonus will be paid in arrears in two annual installments of $0.5 million in December 2020 and execute on programs that meetDecember 2021, respectively. The Retention Bonus payouts are subject to the needscondition of the server, networkingcontinued employment, and data center market. During the year endedtherefore treated as compensation and expensed as incurred.
As of December 31, 2016,2019, the Company had incurred approximately $0.7$3.1 million in external acquisition costs in connection with the acquisitiontransaction, which were expensed as incurred.
The purchase price allocation and related accounting for this acquisition is preliminary. The preliminary fair value estimates for the assets acquired and liabilities assumed were based upon preliminary calculations and valuations and the Company’s estimates and assumptions for the acquisition are subject to change if the Company obtains additional information during the measurement period.
The fair value of the assets acquired has beenwas determined by management primarily by using valuation methods that discount the expected futuremulti-period excess earnings method under the income approach. This method reflects the present value of the projected cash flows that are expected to present value using estimates and assumptions determinedbe generated by management.the existing technologies less charges representing the contribution of other assets to those cash flows. The Company performed a valuation of the net assets acquired as of the August 4, 2016 closing date.Closing Date.
The Company performed a valuation of the net assets acquired as of the Closing Date. The total consideration from the business combinationacquisition was allocated as follows:

 Total
 (in thousands)
Prepaid expenses and other current assets$267
Unbilled receivables6,765
Operating lease right-of-use assets852
Identified intangible assets23,500
Goodwill16,845
Deferred revenue(310)
Operating lease liabilities(852)
Other current liabilities(267)
Total$46,800
NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (Continued)

 Total
 (in thousands)
Inventory$6,300
Property and equipment4,543
Other tangible assets206
Identified intangible assets50,222
Goodwill32,723
Accounts payable and accrued liabilities(3,527)
Deferred revenue(467)
Total$90,000

The goodwill arising from the acquisition is primarily attributed to synergies related to the combination of new and complementary technologies of the Company and the assembled workforce of the acquiredSecure Silicon IP and Protocols business. ThisApproximately $15.0 million of the goodwill is expected to be deductible for tax purposes.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (Continued)

The identified intangible assets assumed in the acquisition of the acquiredSecure Silicon IP and Protocols business were recognized as follows based upon their estimated fair values as of the acquisition date:
 Total Estimated Weighted Average Useful Life
 (in thousands) (in years)
Existing technology$21,600
 3 to 5 years
Customer contracts and contractual relationships900
 5 years
IPR&D1,000
 Not applicable
Total$23,500
  

 Total Estimated Weighted Average Useful Life
 (in thousands) (in years)
Existing technology$44,900
 5
Customer contracts and contractual relationships3,722
 6
In-process research and development1,600
 Not applicable
Total$50,222
  
In-process research and development ("IPR&D")&D consists of one project, primarily relating to the development of process technologies to manufactureMedia Access Control Security frame engines, which is part of the next generation buffer chip product.Silicon IP solutions. The project is expected to be completed over the next 4 years.twelve months. The acquired IPR&D will not be amortized until completion of the related product which is determined by when the underlying projects reachproject reaches technological feasibility and commencecommences commercial production. Upon completion, the IPR&D project will be amortized over its useful life, which is expected to range between 5three years and 7five years.

Snowbush IP Assets
On August 5, 2016, the Company completed its acquisition of the assets of Semtech Corporation's Snowbush IP group for $32.0 million in cash. Snowbush IP, formerly part of Semtech's Systems Innovation Group, is a provider of silicon-proven, high-performance serial link solutions. The Snowbush IP assets have been integrated into the MID reporting unit to bolster its SerDes and IP offerings, addressing critical needs of the server, networking and data center market. During the year ended December 31, 2016, the Company incurred approximately $0.7 million in external acquisition costs in connection with the acquisition which were expensed as incurred.
The fair value of the assets acquired has been determined primarily by using valuation methods that discount the expected future cash flows to present value using estimates and assumptions determined by management. The Company performed a valuation of the net assets acquired as of the August 5, 2016 closing date. The total consideration from the business combination was allocated as follows:

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (Continued)

 Total
 (in thousands)
Property and equipment$911
Identified intangible assets25,189
Goodwill14,015
Deferred revenue(1,270)
Total$38,845
The goodwill arising from the acquisition is primarily attributed to synergies related to the combination of new and complementary technologies of the Company and the assembled workforce of the Snowbush IP assets. This goodwill is expected to be deductible for tax purposes.
The identified intangible assets assumed in the acquisition of the Snowbush IP assets were recognized as follows based upon their estimated fair values as of the acquisition date:
 Total Estimated Weighted Average Useful Life
 (in thousands) (in years)
Existing technology$2,600
 5
Customer contracts and contractual relationships789
 2
In-process research and development21,800
 Not applicable
Total$25,189
  
IPR&D consists of four projects, primarily relating to the development of SerDes and IP process technologies. The projects are expected to be completed over the next 1.5 years. The acquired IPR&D will not be amortized until completion of the related products which is determined by when the underlying projects reach technological feasibility and commence commercial production. Upon completion, each IPR&D project will be amortized over its useful life, each of which is expected to range between 4 years and 6 years. Subsequent to the acquisition, the Company impaired $18.3 million of in-process research and development intangible asset. See Note 5, “Intangible Assets and Goodwill” for further details.

Unaudited Pro Forma Combined Consolidated Financial Information
The following unaudited pro forma financial information presents the combined results of operations for the Company and SCS, the Memory Interconnect Business and the Snowbush IP assetsNorthwest Logic as if the acquisitionsacquisition had occurred on January 1, 2015.2018. The unaudited pro forma financial information has been prepared for comparative purposes only and does not purport to be indicative of the actual operating results that would have been recorded had the acquisitionsacquisition actually taken place on January 1, 2015,2018, and should not be taken as indicative of future consolidated operating results. Additionally, the unaudited pro forma financial results do not include any anticipated synergies or other expected benefits from the acquisitionsacquisition (unaudited, in thousands, except per share amounts):
 Years Ended December 31,
 2019 2018
Revenue$231,492
 $241,049
Net loss$(90,688) $(160,742)
Net loss per share - diluted$(0.82) $(1.48)
 Years Ended
 December 31,
 2016 2015
Revenue$364,443
 $374,036
Net income$5,727
 $188,852
Net income per share - diluted$0.05
 $1.61

Pro forma earningsloss for 2016 were2019 was adjusted to exclude $3.4$0.7 million of acquisition-related costs incurred in 2016.2019. Consequently, pro forma earningsloss for 2015 were2018 was adjusted to include these costs.

Pro forma financial information on the combined results of operations for the Company and the Secure Silicon IP and Protocols business as if the acquisition had occurred on January 1, 2018 has not been presented as it was impracticable to prepare full financial statements for the Secure Silicon IP and Protocols business, given that the Secure Silicon IP and Protocols business had not been managed as a stand-alone business and thus stand-alone financial statements were not readily available.
Additionally, the revenue recognized from the Northwest Logic and Secure Silicon IP and Protocols business acquisitions is not material to the Company’s consolidated financial statements during the year ended December 31, 2019, either individually or in the aggregate. Furthermore, the Company does not track operating results from these businesses separately.

Supplementary Financial Data
RAMBUS INC.
CONSOLIDATED SUPPLEMENTARY FINANCIAL DATA
Quarterly Statements of Operations
(Unaudited)
Dec. 31, 2016 Sept. 30, 2016 June 30, 2016 March 31, 2016 Dec. 31, 2015 Sept. 30, 2015 June 30, 2015 March 31, 2015Dec. 31, 2019 Sept. 30, 2019 June 30, 2019 March 31, 2019 Dec. 31, 2018 Sept. 30, 2018 June 30, 2018 March 31, 2018
(In thousands, except for per share amounts)(In thousands, except for per share amounts)
Total revenue$97,559
 $89,855
 $76,501
 $72,682
 $76,773
 $73,779
 $72,812
 $72,914
$59,947
 $57,399
 $58,297
 $48,384
 $68,563
 $59,754
 $56,458
 $46,426
Total operating costs and expenses (1)$97,035
 $78,039
 $64,493
 $63,388
 $56,439
 $56,139
 $57,258
 $55,022
$73,158
 $80,272
 $95,343
 $79,793
 $72,763
 $78,921
 $76,445
 $90,039
Operating income$524
 $11,816
 $12,008
 $9,294
 $20,334
 $17,640
 $15,554
 $17,892
Net income (loss) (2)$(3,445) $4,511
 $3,876
 $1,878
 $12,992
 $182,033
 $6,861
 $9,502
Net income (loss) per share — basic$(0.03) $0.04
 $0.04
 $0.02
 $0.12
 $1.56
 0.06
 $0.08
Net income (loss) per share — diluted$(0.03) $0.04
 $0.03
 $0.02
 $0.11
 $1.52
 0.06
 $0.08
Operating loss$(13,211) $(22,873) $(37,046) $(31,409) $(4,200) $(19,167) $(19,987) $(43,613)
Net loss (1)$(9,532) $(17,331) $(36,980) $(26,576) $(2,018) $(104,893) $(15,357) $(35,689)
Net loss per share — basic$(0.09) $(0.16) $(0.33) $(0.24) $(0.02) $(0.97) (0.14) $(0.33)
Net loss per share — diluted$(0.09) $(0.16) $(0.33) $(0.24) $(0.02) $(0.97) (0.14) $(0.33)
Shares used in per share calculations — basic (3)(2)110,788
 110,214
 109,904
 109,733
 111,476
 116,444
 116,027
 115,336
111,883
 111,315
 110,875
 109,692
 108,826
 107,897
 107,737
 109,358
Shares used in per share calculations — diluted (3)(2)110,788
 113,723
 112,061
 112,252
 113,388
 119,542
 120,939
 117,442
111,883
 111,315
 110,875
 109,692
 108,826
 107,897
 107,737
 109,358

(1)The quarterly financial information includes $18.3 million of impairment of in-process research and development intangible asset and a reduction of operating expenses due to the change in the contingent consideration liability of $6.8 million innet loss for the quarter ended December 31, 2016.September 30, 2018 included a $91.3 million impact of an increase in our deferred tax asset valuation allowance. Refer to Note 5, “Intangible Assets and Goodwill” of Notes to Consolidated Financial Statements of this Form 10-K. The quarterly financial information also includes restructuring charges of $3.6 million in the quarter ended December 31, 2015. Refer to Note 15, "Restructuring Charges"19, “Income Taxes,” of Notes to Consolidated Financial Statements of this Form 10-K.
(2)The quarterly financial information includes the following amount related to benefit from income taxes related to the deferred tax asset valuation allowance reversal as follows: $174.5 million in the quarter ended September 30, 2015. Refer to Note 16, "Income Taxes" of Notes to Consolidated Financial Statements of this Form 10-K.
(3)The quarterly financial information includes the impact of the accelerated share repurchase program as follows: 0.7 million shares in the quarter ended June 30, 20162018 and 7.83.1 million shares repurchased in the quarter ended DecemberMarch 31, 2015.2018. Refer to Note 13, "Stockholders' Equity"15, “Stockholders’ Equity,” of Notes to Consolidated Financial Statements of this Form 10-K.




INDEX TO EXHIBITS
Exhibit NumberDescription of Document
3.1(1)
3.2(2)
3.3(3)
4.1(4)
4.3(5)
4.4
10.1(6)
10.2(7)*
10.4(8)*
10.5(8)*
10.6(8)*
10.7(9)*
10.8(10)*
10.9(10)*
10.10(9)*
10.11(11)
10.12(12)**
10.13(12)**
10.14(13)
10.15(14)
10.16(14)
10.17(15)**
10.18(16)**
10.19(17)**

10.20(17)**

10.21(17)**

10.22(18)**

10.23(19)

10.24(20)
10.25(5)
10.26(5)
10.27(21)
10.28(21)
10.29(22)

10.30(22)
10.31(22)
10.32(22)
21.1
23.1
24
31.1
31.2
32.1
32.2
101.INS±XBRL Instance Document - the instance document does not appear in the Interactive Data File because its XBRL tags are embedded within the Inline XBRL document.
101.SCH±XBRL Taxonomy Extension Schema Document
101.CAL±XBRL Taxonomy Extension Calculation Linkbase Document
101.LAB±XBRL Taxonomy Extension Label Linkbase Document
101.PRE±XBRL Taxonomy Extension Presentation Linkbase Document
101.DEF±XBRL Taxonomy Extension Definition Linkbase Document
104Cover Page Interactive Data File (formatted as Inline XBRL and contained in Exhibit 101)


*Management contracts or compensation plans or arrangements in which directors or executive officers are eligible to participate.
**Confidential treatment has been granted with respect to certain portions of this exhibit. Omitted portions have been filed separately with the Securities and Exchange Commission.
±XBRL (Extensible Business Reporting Language) information is furnished and not filed or a part of a registration statement or prospectus for purposes of Sections 11 or 12 of the Securities Act of 1933, is deemed not filed for purposes of Section 18 of the Securities Exchange Act of 1934, and otherwise is not subject to liability under these sections.
(1)Incorporated by reference to the Form 10-K filed on December 15, 1997.
(2)Incorporated by reference to the Form 10-Q filed on May 4, 2001.
(3)Incorporated by reference to the Form 8-K filed on April 30, 2013.
(4)Incorporated by reference to the Form S-1/A (file no. 333-22885) filed on April 24, 1997.
(5)Incorporated by reference to the Form 8-K filed on November 17, 2017.
(6)Incorporated by reference to the Form S-1 (file no. 333-22885) filed on March 6, 1997.
(7)Incorporated by reference to the Form 8-K filed on March 9, 2015.
(8)Incorporated by reference to the Form 8-K filed on April 30, 2014.
(9)Incorporated by reference to the Form 8-K filed on April 27, 2018.
(10)Incorporated by reference to the Form 10-Q filed on July 23, 2015.
(11)Incorporated by reference to the Form 10-K filed on February 26, 2010.
(12)Incorporated by reference to the Form 10-Q filed on May 3, 2010.
(13)Incorporated by reference to the Form 10-K filed on February 24, 2012.
(14)Incorporated by reference to the Form 8-K filed on October 29, 2018.
(15)Incorporated by reference to the Form 10-Q/A filed on January 13, 2014.
(16)Incorporated by reference to the Form 10-Q filed on July 29, 2013.
(17)Incorporated by reference to the Form 10-K filed on February 21, 2014.
(18)Incorporated by reference to the Form 10-Q filed on July 23, 2015.
(19)Incorporated by reference to the Form 10-Q filed on July 22, 2016.
(20)Incorporated by reference to the Form 8-K filed on September 21, 2016.
(21)Incorporated by reference to the Form 10-Q filed on August 2, 2019.
(22)Incorporated by reference to the Form 8-K filed on August 28, 2019.


102



SIGNATURES
Pursuant to the requirements of Section 13 or 15(d) of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized.
RAMBUS INC.
  
By:/s/ RAHUL MATHUR
 Rahul Mathur
 Senior Vice President, Finance and Chief Financial Officer
Date: February 17, 201726, 2020


POWER OF ATTORNEY
KNOW ALL PERSONS BY THESE PRESENTS, that each person whose signature appears below hereby constitutes and appoints Ronald BlackLuc Seraphin and Rahul Mathur as his true and lawful agent, proxy and attorney-in-fact, with full power of substitution and resubstitution, for him and in his name, place and stead, in any and all capacities, to (i) act on, sign, and file with the Securities and Exchange Commission any and all amendments to this Annual Report on Form 10-K, together with all schedules and exhibits thereto, (ii) act on, sign, and file such certificates, instruments, agreements and other documents as may be necessary or appropriate in connection therewith, and (iii) take any and all actions that may be necessary or appropriate to be done, as fully for all intents and purposes as he might or could do in person, hereby approving, ratifying and confirming all that such agent, proxy and attorney-in-fact or any of his substitutes may lawfully do or cause to be done by virtue thereof.
Pursuant to the requirements of the Securities Exchange Act of 1934, this report has been signed below by the following persons on behalf of the registrant and in the capacities and on the dates indicated.

SignatureTitleDate
   
/s/ RONALD BLACKLUC SERAPHINChief Executive Officer, President and Director (Principal Executive Officer)February 17, 201726, 2020
Ronald BlackLuc Seraphin  
   
/s/ RAHUL MATHURSenior Vice President, Finance and Chief Financial Officer (Principal Financial and Accounting Officer)February 17, 201726, 2020
Rahul Mathur  
   
/s/ ERIC STANGKEITH JONESChairman of the Board of DirectorsVice President, Chief Accounting Officer and Corporate Controller (Principal Accounting Officer)February 17, 201726, 2020
Eric StangKeith Jones  
   
/s/ J. THOMAS BENTLEYCHARLES KISSNERDirectorChairman of the Board of DirectorsFebruary 17, 201726, 2020
J. Thomas BentleyCharles Kissner  
   
/s/ ELLIS THOMAS FISHERDirectorFebruary 17, 201726, 2020
Ellis Thomas Fisher  
   
/s/ PENELOPE HERSCHEREMIKO HIGASHIDirectorFebruary 17, 201726, 2020
Penelope HerscherEmiko Higashi  
   
/s/ CHARLES KISSNERMEERA RAODirectorFebruary 17, 201726, 2020
Charles KissnerMeera Rao  
   
/s/ DAVID SHRIGLEYSANJAY SARAFDirectorFebruary 17, 201726, 2020
David ShrigleySanjay Saraf
/s/ NECIP SAYINERDirectorFebruary 26, 2020
Necip Sayiner
/s/ ERIC STANGDirectorFebruary 26, 2020
Eric Stang
  
   



INDEX TO EXHIBITS
104
Exhibit NumberDescription of Document
2.1(1)Purchase Agreement, dated January 25, 2016, by and between Rambus Inc. and the shareholders of Smart Card Software Ltd.
3.1(2)Amended and Restated Certificate of Incorporation of Registrant filed May 29, 1997.
3.2(3)Certificate of Amendment of Amended and Restated Certificate of Incorporation of Registrant filed June 14, 2000.
3.3(4)Amended and Restated Bylaws of Registrant dated April 25, 2013.
4.1(5)Form of Registrant’s Common Stock Certificate.
4.2(6)Indenture between Rambus Inc. and U.S. Bank, National Association, dated as of August 16, 2013 (including the form of 1.125% Convertible Senior Note due 2018 therein).
10.1(7)Form of Indemnification Agreement entered into by Registrant with each of its directors and executive officers.
10.2(8)*Form of Change of Control Severance Agreement, Agreement entered into by Registrant with each of its named executive officers other than its chief executive officer.
10.3(9)*1997 Stock Plan (as amended and restated as of April 4, 2007) and related forms of agreements.
10.4(10)*2006 Equity Incentive Plan, as amended.
10.5(10)*Forms of agreements under the 2006 Equity Incentive Plan, as amended.
10.6(10)*2006 Employee Stock Purchase Plan as amended.
10.7(11)*2015 Equity Incentive Plan.
10.8(12)*Form of Restricted Stock Unit Agreement (2015 Equity Incentive Plan).
10.9(12)*Form of Stock Option Agreement (2015 Equity Incentive Plan).
10.10(11)*2015 Employee Stock Purchase Plan.
10.11(13)Triple Net Space Lease, dated as of December 15, 2009, by and between Registrant and MT SPE, LLC.
10.12(14)**Settlement Agreement, dated January 19, 2010, among Registrant, Samsung Electronics Co., Ltd, Samsung Electronics America, Inc., Samsung Semiconductor, Inc. and Samsung Austin Semiconductor, L.P.
10.13(14)**Semiconductor Patent License Agreement, dated January 19, 2010, between Registrant and Samsung Electronics Co., Ltd.
10.14(15)

First Amendment of Lease, dated November 4, 2011, by and between Registrant and MT SPE, LLC.
10.15(16)

Employment Agreement between the Company and Ronald Black, dated as of June 22, 2012.
10.16(17)**

Settlement Agreement, dated June 11, 2013, among Registrant, SK hynix and certain SK hynix affiliates.
10.17(18)**

Semiconductor Patent License Agreement, dated June 11, 2013, between Registrant and SK hynix.
10.18(19)**

Settlement Agreement, dated December 9, 2013, between Rambus Inc., Micron Technology, Inc., and certain Micron affiliates.
10.19(19)**

Semiconductor Patent License Agreement, dated December 9, 2013, between Rambus, Inc. and Micron Technology, Inc.
10.20(19)**

Amendment to Semiconductor Patent License Agreement, dated December 30, 2013, by and between Rambus Inc. and Samsung Electronics Co., Ltd.
10.21(20)**

Amendment 1 to Semiconductor Patent License Agreement, dated June 17, 2015, by and between Rambus Inc. and SK hynix Inc.
10.22(21)

Master Agreement, dated October 26, 2015, by and between Rambus Inc. and Citibank, N.A.
10.23(22)

Asset Purchase Agreement, dated June 29, 2016, by and between Rambus Inc., Bell ID Singapore Ptd Ltd, Inphi Corporation and Inphi International Pte. Ltd.
10.24(23)Separation Agreement, dated August 5, 2016 by and between Rambus Inc. and Satish Rishi.

10.25(24)Offer Letter, dated September 9, 2016, by and between Rambus Inc. and Rahul Mathur.
12.1(25)Computation of ratio of earnings to fixed charges.
21.1Subsidiaries of Registrant.
23.1Consent of Independent Registered Public Accounting Firm.
24Power of Attorney (included in signature page).
31.1Certification of Principal Executive Officer, pursuant to Rule 13a-14(a) and Rule 15d-14(a) of the Securities Exchange Act of 1934, as amended, as adopted pursuant to Section 302 of the Sarbanes-Oxley Act of 2002.
31.2Certification of Principal Financial Officer, pursuant to Rule 13a-14(a) and Rule 15d-14(a) of the Securities Exchange Act of 1934, as amended, as adopted pursuant to Section 302 of the Sarbanes-Oxley Act of 2002.
32.1Certification of Principal Executive Officer, pursuant to 18 U.S.C. Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002.
32.2Certification of Principal Financial Officer, pursuant to 18 U.S.C. Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002.
101.INS±XBRL Instance Document
101.SCH±XBRL Taxonomy Extension Schema Document
101.CAL±XBRL Taxonomy Extension Calculation Linkbase Document
101.LAB±XBRL Taxonomy Extension Label Linkbase Document
101.PRE±XBRL Taxonomy Extension Presentation Linkbase Document
101.DEF±XBRL Taxonomy Extension Definition Linkbase Document


*Management contracts or compensation plans or arrangements in which directors or executive officers are eligible to participate.
**Confidential treatment has been granted with respect to certain portions of this exhibit. Omitted portions have been filed separately with the Securities and Exchange Commission.
±XBRL (Extensible Business Reporting Language) information is furnished and not filed or a part of a registration statement or prospectus for purposes of Sections 11 or 12 of the Securities Act of 1933, is deemed not filed for purposes of Section 18 of the Securities Exchange Act of 1934, and otherwise is not subject to liability under these sections.
(1)Incorporated by reference to the Form 10-Q filed on April 22, 2016.
(2)Incorporated by reference to the Form 10-K filed on December 15, 1997.
(3)Incorporated by reference to the Form 10-Q filed on May 4, 2001.
(4)Incorporated by reference to the Form 8-K filed on April 30, 2013.
(5)Incorporated by reference to the Form S-1/A (file no. 333-22885) filed on April 24, 1997.
(6)Incorporated by reference to the Form 8-K filed on August 16, 2013.
(7)Incorporated by reference to the Form S-1 (file no. 333-22885) filed on March 6, 1997.
(8)Incorporated by reference to the Form 8-K filed on March 9, 2015.
(9)Incorporated by reference to the Form 10-K filed on September 14, 2007.
(10)Incorporated by reference to the Form 8-K filed on April 30, 2014.
(11)Incorporated by reference to the Form 8-K filed on April 28, 2015.
(12)Incorporated by reference to the Form 10-Q filed on July 23, 2015.
(13)Incorporated by reference to the Form 10-K filed on February 26, 2010.
(14)Incorporated by reference to the Form 10-Q filed on May 3, 2010.
(15)Incorporated by reference to the Form 10-K filed on February 24, 2012.
(16)Incorporated by reference to the Form 8-K filed on June 25, 2012.
(17)Incorporated by reference to the Form 10-Q/A filed on January 13, 2014.
(18)Incorporated by reference to the Form 10-Q filed on July 29, 2013.
(19)Incorporated by reference to the Form 10-K filed on February 21, 2014.
(20)Incorporated by reference to the Form 10-Q filed on July 23, 2015.
(21)Incorporated by reference to the Form 10-K filed on February 19, 2016.
(22)Incorporated by reference to the Form 10-Q filed on July 22, 2016.
(23)Incorporated by reference to the Form 10-Q filed on October 28, 2016.
(24)Incorporated by reference to the Form 8-K filed on September 21, 2016.
(25)Incorporated by reference to the Form S-3 filed on June 22, 2009.


103