Summary of Significant Accounting Policies | Note 1. Summary of Significant Accounting Policies Principles of Consolidation and Basis of Presentation The accompanying unaudited condensed consolidated financial statements include those of Cerus Corporation and its subsidiary, Cerus Europe B.V. (together with Cerus Corporation, hereinafter “Cerus” or the “Company”) after elimination of all intercompany accounts and transactions. These unaudited condensed consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States (“GAAP”) for interim financial information and pursuant to the rules and regulations of the Securities and Exchange Commission (“SEC”). Accordingly, they do not include all of the information and footnotes required by GAAP for complete financial statements. In the opinion of management, all adjustments, consisting of normal recurring entries, considered necessary for a fair presentation have been made. Operating results for the three and nine months ended September 30, 2015, are not necessarily indicative of the results that may be expected for the year ending December 31, 2015, or for any future periods. These unaudited condensed consolidated financial statements and notes thereto should be read in conjunction with the Company’s audited consolidated financial statements and notes thereto for the year ended December 31, 2014, which were included in the Company’s 2014 Annual Report on Form 10-K, filed with the SEC on March 16, 2015. The accompanying condensed consolidated balance sheet as of December 31, 2014, has been derived from the Company’s audited consolidated financial statements as of that date. Use of Estimates The preparation of financial statements requires management to make estimates, assumptions and judgments that affect the reported amounts of assets, liabilities, revenue and expenses, and related disclosures of contingent assets and liabilities. On an ongoing basis, management evaluates its estimates, which are based on historical experience and on various other assumptions that are believed to be reasonable under the circumstances. Actual results may differ from those estimates under different assumptions or conditions. Reclassifications Certain reclassifications have been made to prior period reported amounts to conform to the current period presentations. Previously the Company had presented the amortization of premium and accretion of any discount resulting from the purchase of fixed income securities as a component of “Interest expense” on the unaudited condensed consolidated statements of operations. For the three and nine months ended September 30, 2014, the Company has reclassified approximately $0.1 million and $0.3 million, respectively, of the amortization of premium resulting from the purchase of fixed income securities as a component of “Other income, net” on the unaudited condensed consolidated statements of operations. This reclassification had no impact on net loss, total assets or total stockholders’ equity. Revenue The Company recognizes revenue in accordance with Accounting Standards Codification (“ASC”) Topic 605-25, “Revenue Recognition – Arrangements with Multiple Deliverables,” Revenue related to sales is generally recognized when the Company fulfills its obligations for each element of an agreement. For all sales of the Company’s INTERCEPT Blood System products, the Company uses a binding purchase order and signed sales contract as evidence of an arrangement. The Company sells its platelet and plasma systems directly to blood banks, hospitals, universities and government agencies, as well as to distributors in certain regions. Generally, the Company’s contracts with its customers do not provide for open return rights, except within a reasonable time after receipt of goods in the case of defective or non-conforming product. Deliverables and the units of accounting vary according to the provisions of each purchase order or sales contract. For revenue arrangements with multiple elements, the Company determines whether the delivered elements meet the criteria as separate units of accounting. Such criteria require that the deliverable have stand-alone value to the customer and that if a general right of return exists relative to the delivered item, delivery or performance of the undelivered item(s) is considered probable and substantially in the control of the Company. Once the Company determines if the deliverable meets the criteria for a separate unit of accounting, the Company must determine how the consideration should be allocated between the deliverables and how the separate units of accounting should be recognized as revenue. Consideration received is allocated to elements that are identified as discrete units of accounting. Because the Company has no vendor specific objective evidence or third party evidence for its products due to the Company’s variability in its pricing across the regions into which it sells its products, the allocation of revenue is based on best estimated selling price for the products sold. The objective of best estimated selling price is to determine the price at which the Company would transact a sale, had the product been sold on a stand-alone basis. The Company determines best estimated selling price for its products by considering multiple factors, including, but not limited to, features and functionality of the system, geographies, type of customer, and market conditions. The Company regularly reviews best estimated selling price, as applicable. Freight costs charged to customers are recorded as a component of revenue under ASC Topic 605, “Accounting for Shipping and Handling Fees and Costs.” Research and Development Expenses In accordance with ASC Topic 730, “Accounting for Research and Development Expenses,” The Company’s use of estimates in recording accrued liabilities for research and development activities (see “Use of Estimates” above) affects the amounts of research and development expenses recorded and revenue recorded from development funding and government grants and collaborative agreements. Actual results may differ from those estimates under different assumptions or conditions. Cash Equivalents The Company considers all highly liquid investments with original maturities of three months or less from the date of purchase to be classified as cash equivalents. These investments primarily consist of money market instruments, and are classified as available-for-sale. Investments Investments with original maturities of greater than three months, primarily corporate debt, U.S. government agency securities and marketable equity securities of Aduro Biotech, Inc. (“Aduro”), are designated as available-for-sale and classified as short-term investments, in accordance with ASC Topic 320, “ Accounting for Certain Investments in Debt and Equity Securities The Company also reviews its marketable securities on a regular basis to evaluate whether any security has experienced an other-than-temporary decline in fair value. Other-than-temporary declines in market value, if any, are recorded in “Other income, net” on the Company’s unaudited condensed consolidated statements of operations. Restricted Cash The Company holds a certificate of deposit with a domestic bank for any potential decommissioning resulting from the Company’s possession of radioactive material. The certificate of deposit is held to satisfy the financial surety requirements of the California Department of Health Services and is recorded in “Restricted cash” on the Company’s unaudited condensed consolidated balance sheets. The Company also has non-US dollar denominated deposits recorded as “Restricted cash” in compliance with certain foreign contractual requirements. Concentration of Credit Risk Financial instruments that potentially subject the Company to concentrations of credit risk consist primarily of cash equivalents, short-term investments and accounts receivable. Pursuant to the Company’s investment policy, substantially all of the Company’s cash, cash equivalents and non-equity short-term investments are maintained at major financial institutions of high credit standing. The Company monitors the financial credit worthiness of the issuers of its investments and limits the concentration in individual securities and types of investments that exist within its investment portfolio. Generally, all of the Company’s investments are investment grade and carry high credit quality ratings, which is in accordance with its investment policy. At September 30, 2015, the fair value of the Company’s marketable equity securities of Aduro is subject to the underlying volatility of Aduro’s stock price. At September 30, 2015, the Company does not believe there is significant financial risk from non-performance by the issuers of the Company’s cash equivalents. Concentrations of credit risk with respect to trade receivables exist. On a regular basis, including at the time of sale, the Company performs credit evaluations of its significant customers that it expects to sell to on credit terms. Generally, the Company does not require collateral from its customers to secure accounts receivable. To the extent that the Company determines specific invoices or customer accounts may be uncollectible, the Company establishes an allowance for doubtful accounts against the accounts receivable on its unaudited condensed consolidated balance sheets and records a charge on its unaudited condensed consolidated statements of operations as a component of selling, general and administrative expenses. At September 30, 2015 and December 31, 2014, the Company had not recorded any reserves for potentially uncollectible accounts. The Company had two and one customer that accounted for more than 10% of the Company’s outstanding trade receivables at each of September 30, 2015 and December 31, 2014, respectively. These customers cumulatively represented approximately 42% and 36% of the Company’s outstanding trade receivables at September 30, 2015 and December 31, 2014, respectively. To date, the Company has not experienced collection difficulties from these customers. Inventories At September 30, 2015 and December 31, 2014, inventory consisted of work-in-process and finished goods only. Finished goods include INTERCEPT disposable kits, UVA illumination devices (“illuminators”), and certain replacement parts for the illuminators. Platelet and plasma systems disposable kits generally have a two-year shelf life from the date of manufacture. Illuminators and replacement parts do not have regulated expiration dates. Work-in-process includes certain components that are manufactured before being sold to and ultimately incorporated and assembled by Fresenius Kabi Deutschland GmbH or Fresenius, Inc. (with their affiliates, “Fresenius”) into the finished INTERCEPT disposable kits. The Company maintains an inventory balance based on its current sales projections, and at each reporting period, the Company evaluates whether its work-in-process inventory would be sold to Fresenius for production of finished units in order to sell to existing and prospective customers within the next twelve-month period. It is not customary for the Company’s production cycle for inventory to exceed twelve months. Instead, the Company uses its best judgment to factor in lead times for the production of its work-in-process and finished units to meet the Company’s forecasted demands. If actual results differ from those estimates, work-in-process inventory could potentially accumulate for periods exceeding one year. At September 30, 2015 and December 31, 2014, the Company classified its work-in-process inventory as a current asset on its consolidated balance sheets based on its evaluation that the work-in-process inventory would be sold to Fresenius for finished disposable kit production within each respective subsequent twelve-month period. Inventory is recorded at the lower of cost, determined on a first-in, first-out basis, or market value. The Company uses significant judgment to analyze and determine if the composition of its inventory is obsolete, slow-moving or unsalable and frequently reviews such determinations. The Company writes-down specifically identified unusable, obsolete, slow-moving, or known unsalable inventory that has no alternative use in the period that it is first recognized by using a number of factors including product expiration dates, open and unfulfilled orders, and sales forecasts. Any write-down of its inventory to net realizable value establishes a new cost basis and will be maintained even if certain circumstances suggest that the inventory is recoverable in subsequent periods. Costs associated with the write-down of inventory are recorded in “Cost of revenue” on the Company’s unaudited condensed consolidated statements of operations. At September 30, 2015 and December 31, 2014, the Company had $1.3 million and $0.1 million, respectively, recorded for potential obsolete, expiring or unsalable product. Property and Equipment, net Property and equipment is comprised of furniture, equipment, leasehold improvements, information technology hardware and software and is recorded at cost. At the time the property and equipment is ready for its intended use, it is depreciated on a straight-line basis over the estimated useful lives of the assets (generally three to five years). Leasehold improvements are amortized on a straight-line basis over the shorter of the lease term or the estimated useful lives of the improvements. Capitalization of Software Costs The Company capitalizes certain significant costs incurred in the acquisition and development of software for internal use, including the costs of the software, materials, and consultants during the application development stage. Costs incurred prior to the application development stage, costs incurred once the application is substantially complete and ready for its intended use, and other costs not qualifying for capitalization, including training and maintenance costs, are charged to expense as incurred. The Company capitalized costs for enhancement of the enterprise resource planning software system and other internal use software of zero and $1.8 million during the nine months ended September 30, 2015 and 2014, respectively. Capitalized software costs associated with the enterprise resource planning system are being amortized over the estimated useful life of five years. Costs incurred in connection with the development of software products for sale are accounted for in accordance with the ASC 985— Costs of Software to Be Sold, Leased or Marketed Goodwill and Intangible Assets, net Intangible assets, net, which include a license for the right to commercialize the INTERCEPT Blood System in Asia, are subject to ratable amortization over the estimated useful life of ten years. The amortization of the Company’s intangible assets, net, is recorded in “Amortization of intangible assets” on the Company’s unaudited condensed consolidated statements of operations. Goodwill is not amortized but instead is subject to an impairment test performed on an annual basis, or more frequently if events or changes in circumstances indicate that goodwill may be impaired. Such impairment analysis is performed on August 31 of each fiscal year, or more frequently if indicators of impairment exist. The test for goodwill impairment may be assessed using qualitative factors to determine whether it is more likely than not that the fair value of a reporting unit is less than the carrying amount. If the Company determines that it is more likely than not that the fair value of a reporting unit is less than the carrying amount, the Company must then proceed with performing the quantitative two-step process to test goodwill for impairment; otherwise, goodwill is not considered impaired and no further testing is warranted. The Company may choose not to perform the qualitative assessment to test goodwill for impairment and proceed directly to the quantitative two-step process; however, the Company may revert to the qualitative assessment to test goodwill for impairment in any subsequent period. The first step of the two-step process compares the fair value of each reporting unit with its respective carrying amount, including goodwill. The Company has determined that it operates in one segment and has one reporting unit and estimates the fair value of its one reporting unit using the enterprise approach under which it considers the quoted market capitalization of the Company as reported on the Nasdaq Global Market. The Company considers quoted market prices that are available in active markets to be the best evidence of fair value. The Company also considers other factors, which include future forecasted results, the economic environment and overall market conditions. If the fair value of the reporting unit exceeds its carrying amount, goodwill of the reporting unit is not considered impaired and, therefore, the second step of the impairment test is unnecessary. The second step of the two-step process, which is used to measure the amount of impairment loss, compares the implied fair value of each reporting unit’s goodwill with the respective carrying amount of that goodwill. If the carrying amount of the reporting unit’s goodwill exceeds the implied fair value of that goodwill, an impairment loss is recognized in an amount equal to that excess. The Company performs an impairment test on its intangible assets, in accordance ASC Topic 360-10, “Property, Plant and Equipment,” Long-lived Assets The Company evaluates its long-lived assets for impairment by continually monitoring events and changes in circumstances that could indicate carrying amounts of its long-lived assets may not be recoverable. When such events or changes in circumstances occur, the Company assesses recoverability by determining whether the carrying value of such assets will be recovered through the undiscounted expected future cash flows. If the expected undiscounted future cash flows are less than the carrying amount of these assets, the Company then measures the amount of the impairment loss based on the excess of the carrying amount over the fair value of the assets. The Company did not recognize impairment charges related to its long-lived assets during the three and nine months ended September 30, 2015 and 2014. Foreign Currency Remeasurement The functional currency of the Company’s foreign subsidiary is the United States dollar. Monetary assets and liabilities denominated in foreign currencies are remeasured in United States dollars using the exchange rates at the balance sheet date. Non-monetary assets and liabilities denominated in foreign currencies are remeasured in United States dollars using historical exchange rates. Revenues and expenses are remeasured using average exchange rates prevailing during the period. Remeasurements are recorded in the Company’s unaudited condensed consolidated statements of operations. Stock-Based Compensation The Company accounts for stock-based compensation in accordance with ASC Topic 718, “Compensation – Stock Compensation.” For stock-based awards issued to non-employees, the Company follows ASC Topic 505-50, “Equity Based Payment to Non-Employees” See Note 11 in the Notes to Unaudited Condensed Consolidated Financial Statements for further information regarding the Company’s stock-based compensation assumptions and expenses. Warrant Liability In August 2009 and November 2010, the Company issued warrants to purchase an aggregate of 2.4 million and 3.7 million shares of common stock, respectively. The material terms of the warrants were identical under each issuance except for the exercise price, date issued and expiration date. In August 2014, all of the outstanding August 2009 warrants were exercised in full. The Company classifies warrants outstanding on the reporting date as a liability on its unaudited condensed consolidated balance sheets as the warrants contain certain material terms which require the Company to purchase the warrants for cash in an amount equal to the value of the unexercised portion of the warrants in connection with certain change of control transactions. In addition, the Company may also be required to pay cash to a warrant holder under certain circumstances if the Company is unable to timely deliver the shares acquired upon warrant exercise to such holder. The fair value of outstanding warrants is calculated using the Black-Scholes model and was adjusted accordingly at the end of each reporting period. Changes resulting from the revaluation of warrants to fair value are recorded in “Gain from revaluation of warrant liability” on the unaudited condensed consolidated statements of operations. Upon the exercise or modification to remove the provisions which require the warrants to be treated as a liability, the fair value of the warrants will be reclassified from a liability to stockholders’ equity on the Company’s unaudited condensed consolidated balance sheets and no further adjustment to the fair value would be made in subsequent periods. See Note 10 in the Notes to Unaudited Condensed Consolidated Financial Statements for further information regarding the Company’s valuation of warrant liability. Income Taxes The Company accounts for income taxes using an asset and liability approach in accordance with ASC Topic 740 “Accounting for Income Taxes.” Net Loss Per Share Basic net loss per share is computed by dividing net loss by the weighted average number of common shares outstanding for the period. Diluted net loss per share gives effect to all potentially dilutive common shares outstanding for the period. The potentially dilutive securities include stock options, employee stock purchase plan rights and warrants, which are calculated using the treasury stock method. Diluted net loss per share also gives effect to potential adjustments to the numerator for changes resulting from the revaluation of warrants to fair value for the period, even if the Company is in a net loss position, if the effect would result in more dilution. Certain potential dilutive securities were excluded from the dilution calculation for the three and nine months ended September 30, 2015 and 2014, as their inclusion would have been anti-dilutive. The following table sets forth the reconciliation of the numerator and denominator used in the computation of basic and diluted net loss per share for the three and nine months ended September 30, 2015 and 2014 (in thousands, except per share amounts): Three Months Ended Nine Months Ended September 30, September 30, 2015 2014 2015 2014 Numerator for Basic and Diluted: Net loss used for basic calculation $ (15,680 ) $ (10,759 ) $ (41,112 ) $ (18,573 ) Effect of revaluation of warrant liability (1,109 ) (1,738 ) (4,698 ) (14,263 ) Adjusted net loss used for diluted calculation $ (16,789 ) $ (12,497 ) $ (45,810 ) $ (32,836 ) Denominator: Basic weighted average number of shares outstanding 96,864 75,194 95,347 73,407 Effect of dilutive potential shares 741 909 993 2,030 Diluted weighted average number of shares outstanding 97,605 76,103 96,340 75,437 Net loss per share: Basic $ (0.16 ) $ (0.14 ) $ (0.43 ) $ (0.25 ) Diluted $ (0.17 ) $ (0.16 ) $ (0.48 ) $ (0.44 ) The table below presents shares underlying stock options that are excluded from the calculation of the weighted average number of shares outstanding used for the calculation of diluted net loss per share. These are excluded from the calculation due to their anti-dilutive effect for the three and nine months ended September 30, 2015 and 2014 (in thousands): Three Months Ended Nine Months Ended September 30, September 30, 2015 2014 2015 2014 Weighted average number of anti-dilutive potential shares: Stock options 7,068 12,032 6,223 11,737 Guarantee and Indemnification Arrangements The Company recognizes the fair value for guarantee and indemnification arrangements issued or modified by the Company. In addition, the Company monitors the conditions that are subject to the guarantees and indemnifications in order to identify if a loss has occurred. If the Company determines it is probable that a loss has occurred, then any such estimable loss would be recognized under those guarantees and indemnifications. Some of the agreements that the Company is a party to contain provisions that indemnify the counter party from damages and costs resulting from claims that the Company’s technology infringes the intellectual property rights of a third party or claims that the sale or use of the Company’s products have caused personal injury or other damage or loss. The Company has not received any such requests for indemnification under these provisions and has not been required to make material payments pursuant to these provisions. The Company generally provides for a one-year warranty on certain of its INTERCEPT blood-safety products covering defects in materials and workmanship. The Company accrues costs associated with warranty obligations when claims are probable. The Company has not experienced significant or systemic warranty claims nor is it aware of any existing current warranty claims and did not carry a warranty claim liability at September 30, 2015 and December 31, 2014. Fair Value of Financial Instruments The Company applies the provisions of fair value relating to its financial assets and liabilities. The carrying amounts of accounts receivables, accounts payable, and other accrued liabilities approximate their fair value due to the relative short-term maturities of such instruments. Based on the borrowing rates currently available to the Company for loans with similar terms, the Company believes the fair value of its debt also approximates its carrying amounts. The Company measures and records certain financial assets and liabilities at fair value on a recurring basis, including its available-for-sale securities and warrant liability. The Company classifies instruments within Level 1 if quoted prices are available in active markets for identical assets. The Company classifies instruments in Level 2 if the instruments are valued using observable inputs to quoted market prices, benchmark yields, reported trades, broker/dealer quotes or alternative pricing sources with reasonable levels of price transparency. The available-for-sale securities are held by a custodian who obtains investment prices from a third party pricing provider that uses standard inputs (observable in the market) to models which vary by asset class. The Company classifies instruments in Level 3 if one or more significant inputs or significant value drivers are unobservable, which include its warrant liability. The Company assesses any transfers among fair value measurement levels at the end of each reporting period. See Notes 2 and 10 in the Notes to Unaudited Condensed Consolidated Financial Statements for further information regarding the Company’s valuation of financial instruments. New Accounting Pronouncements In May 2014, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) No. 2014-09, Revenue from Contracts with Customers (Topic 606), Revenue from Contracts with Customers (Topic 606), Deferral of the Effective Date In August 2014, the FASB issued ASU No. 2014-15, Presentation of Financial Statements—Going Concern Subtopic 205-40): Disclosure of Uncertainties about an Entity’s Ability to Continue as a Going Concern In April 2015, the FASB issued ASU No. 2015-03, Interest—Imputation of Interest (Subtopic 835-30): Simplifying the Presentation of Debt Issuance Costs In July 2015, the FASB issued ASU No. 2015-11, Inventory (Topic 330), Simplifying the Measurement of Inventory |