CAUTIONARY STATEMENTS

Unless otherwise indicated or except where the context otherwise requires, the terms “we,” “us” and “our” and other similar terms in this Annual Report on Form 10-K (the “Annual Report”) refer to Ventas, Inc. and its consolidated subsidiaries.

Forward-Looking Statements

PART I

BUSINESS

Overview

As of December 31, 2018,2020, we leased a total of 442366 properties (excluding properties within our office operations reportable business segment) to various healthcare operating companies under “triple-net” or “absolute-net” leases that obligate the tenants to pay all property-related expenses, including maintenance, utilities, repairs, taxes, insurance and capital expenditures.

Through our Lillibridge Healthcare Services, Inc. (“Lillibridge”) subsidiary and our ownership interest in PMB Real Estate Services LLC (“PMBRES”), we also provide MOB management, leasing, marketing, facility development and advisory services to highly rated hospitals and health systems throughout the United States. In addition, from time to time, we make secured and non-mortgage loans and other investments relating to seniorssenior housing and healthcare operators or properties.

Business Strategy

Generating reliable and growing cash flows from our seniorssenior housing and healthcare assets enables us to pay regular cash dividends to stockholders and creates opportunities to increase stockholder value through profitable investments. The

We believe that maintaining a balanced portfolio of high-quality assets diversified by investment type, geographic location, asset type, tenant/tenant or operator, revenue source and operating model diminishes the risk that any single factor or event could materially harm our business. Portfolio diversification also enhances the reliability of our cash flows by reducing our exposure to any particular asset class or market, or individual tenant, operatorborrower or manager and making us less susceptible to single-statecertain risks, including risks related to regulatory or reimbursement changes, regional climate events and local economic downturns.downturns or global health events.

A strong, flexible balance sheet and excellent liquidity position us favorably to capitalize on strategic growth opportunities in the seniorssenior housing and healthcare industries through acquisitions, investments and development and redevelopment projects. We maintain our financial strength to pursue profitable investment opportunities by actively managing our leverage, improving our cost of capital and preserving our access to multiple sources of capital and liquidity, including unsecured bank debt, mortgage financings and public and private debt and equity markets.

Portfolio Summary

The following table summarizes our consolidated portfolio of properties and other investments, including construction in progress, as of and for the year ended December 31, 2018:2020:

Our seniorssenior housing communities include independent and assisted living communities, continuing care retirement communities and communities providing care for individuals with Alzheimer’s disease and other forms of dementia or memory loss. These communities offer studio, one bedroomone- and two bedroomtwo-bedroom residential units on a month-to-month basis primarily to elderly individuals requiring various levels of assistance. Basic services for residents of these communities include housekeeping,

Typically, our MOBs are multi-tenant properties leased to several unrelated medical practices, although in many cases they may be associated with a large single specialty or multi-specialty group. Tenants include physicians, dentists, psychologists, therapists and other healthcare providers, who require space devoted to patient examination and treatment, diagnostic imaging, outpatient surgery and other outpatient services. MOBs are similar to commercial office buildings, although they require greater plumbing, electrical and mechanical systems to accommodate physicians’ requirements such as sinks in every room, brighter lights and specialized medical equipment. As of December 31, 2018,2020, we owned or managed through unconsolidated real estate entities for third parties approximately 2221 million square feet of MOBs that are predominantly located on or near a health system.

Our life science, research and innovation centers contain laboratory and office space primarily for scientific research for universities, academic medical centers, technology, biotechnology, medical device and pharmaceutical companies and other organizations involved in the life science, research and innovation industry. While these properties have characteristics similar to commercial office buildings, they generally contain more advanced electrical, mechanical, and heating, ventilating and air conditioning systems. The facilities generally have specialty equipment including emergency generators, fume hoods, lab bench tops and related amenities. In many instances, research and innovation center tenants make significant investments to improve their leased space, in addition to landlord improvements, to accommodate biology, chemistry or medical device research initiatives. Our research and innovation centers are primarilyoften located on or contiguous to university and academic medical campuses. The campus settings allow usAs of December 31, 2020, we own or have investments in nearly 9 million square feet spanning 40 operating properties and three in progress ground-up development properties, including a presence in the opportunity to provide flexible, contiguous/adjacent expansion to accommodate the growth of existing tenants.top two life sciences clusters, South San Francisco, California and Cambridge, Massachusetts.

We have 29 properties that are operated as LTACs. LTACs have a Medicare average length of stay of greater than 25 days and serve medically complex, chronically ill patients who require a high level of monitoring and specialized care, but whose conditions do not necessitate the continued services of an intensive care unit. The operators of these LTACs have the capability to treat patients who suffer from multiple systemic failures or conditions such as neurological disorders, head injuries, brain stem and spinal cord trauma, cerebral vascular accidents, chemical brain injuries, central nervous system

We have 1213 properties that are operated as health systems. Health systems provide medical and surgical services, including inpatient care, intensive care, cardiac care, diagnostic services and emergency services. These health systems also provide outpatient services such as outpatient surgery, laboratory, radiology, respiratory therapy, cardiology and physical therapy. In the United States, these health systems receive payments for patient services from the federal government primarily

We have 1716 properties that are operated as SNFs. SNFs provide rehabilitative, restorative, skilled nursing and medical treatment for patients and residents who do not require the high technology, care-intensive, high costhigh-cost setting of an acute care or rehabilitation hospital. Treatment programs include physical, occupational, speech, respiratory and other therapies, including sub-acute clinical protocols such as wound care and intravenous drug treatment. Charges for these services are generally paid from a combination of government reimbursement and private sources.

Our portfolio of seniors housing and healthcare propertiesassets is broadly diversified by geographic location throughout the United States, Canada and the United Kingdom, with properties in only one state (California) accounting for more than 10% of our total continuing revenues and net operating income (“NOI,” which is defined as total revenues, excluding interest and other income, less property-level operating expenses and office building services costs) for the year ended December 31, 2018.2020.

As of December 31, 2018,2020, we had $756.5 million$0.9 billion of net loans receivable and investments relating to seniorssenior housing and healthcare operators or properties. Our loans receivable and investments provide us with interest income, principal amortization and transaction fees and are typically secured by mortgage liens or leasehold mortgages on the underlying properties and corporate or personal guarantees by affiliates of the borrowing entity. In some cases, the loans are secured by a pledge of ownership interests in the entity or entities that own the related seniors housing or healthcare properties. From time to time, we also make investments in mezzanine loans, which are subordinated to senior secured loans held by other investors that encumber the same real estate. See “NOTE 6—LOANS RECEIVABLE AND INVESTMENTS”“Note 6 – Loans Receivable and Investments” of the Notes to Consolidated Financial Statements included in Part II, Item 8 of this Annual Report on Form 10-K.Report.

We are party to certain agreements that obligate us to develop seniors housing or healthcare properties funded through capital that we and, in certain circumstances, our joint venture partners provide. As of December 31, 2018,2020, we had 1913 properties under development pursuant to these agreements, including fivethree properties that are owned through unconsolidated real estate entities. In addition, from time to time, we engage in redevelopment projects with respect to our existing seniors housing communitiesproperties to maximize the value, increase NOI, maintain a market-competitive position, achieve property stabilization or change the primary use of the property.

Segment Information

We operate through three reportable business segments: triple-net leased properties, senior living operations and office operations. Non-segment assets, classified as “all other,” consist primarily of corporate assets, including cash, restricted cash, loans receivable and investments, and miscellaneous accounts receivable. Our chief operating decision makers evaluate performance of the combined properties in each reportable business segment and determine how to allocate resources to these segments, in significant part, based on segment NOI and related measures. For further information regarding our business

Each ofIn our triple-net leased properties segment, we invest in and own senior housing and healthcare properties throughout the United States and the United Kingdom and lease those properties to healthcare operating companies under “triple-net” or “absolute-net” leases with Brookdale Senior Living, Ardent and Kindred is a triple-net lease that obligatesobligate the tenanttenants to pay all property-related expenses, including maintenance, utilities, repairs, taxes, insurance and capital expenditures, and to comply with the terms of the mortgage financing documents, if any, affecting the properties.

Each of our leases with Brookdale Senior Living, Ardent and Kindred is a triple-net lease. In addition, each of our Brookdale Senior Living, Ardent and Kindred leases has a corporate guaranty.

As of December 31, 2018,2020, we leased 129121 consolidated properties (excluding twoeight properties managed by Brookdale Senior Living pursuant to a long-term management agreementagreements and included in the senior living operations reportable business segment) to Brookdale Senior Living.

Pursuant to ourIn July 2020, we entered into a revised master lease agreement (the “Brookdale Lease”) and certain other agreements (together with the Brookdale Lease, the “Agreements”) with Brookdale Senior Living.

As of December 31, 2018,2020, the aggregate 20192021 contractual cash rent due to us from Brookdale Senior Living including a reduction for an annual rent credit equal to $8.0 million, was approximately $179.2$100.3 million, and the current aggregate contractual base rent (computed in accordance with U.S. generally accepted accounting principles (“GAAP”)) due to us from Brookdale Senior Living was approximately $179.5$148.5 million.) See “NOTE 3—CONCENTRATION OF CREDIT RISK” and “NOTE 14—COMMITMENTS AND CONTINGENCIES” of the Notes to Consolidated Financial Statements included in Part II, Item 8 of this Annual Report on Form 10-K.

As of December 31, 2018,2020, we leased 1011 properties (excluding one MOB leased to Ardent under a separate lease) to Ardent pursuant to a single, triple-net master lease agreement. Per our master lease agreement, Ardent is obligated to pay base rent, which escalates annually by the lesser of four times the increase in the consumer price indexConsumer Price Index (“CPI”) for the relevant period and 2.5%.  The initial term of the master lease expires on August 31, 2035 and Ardent has one ten-year renewal option.

As of December 31, 2018,2020, the aggregate 20192021 contractual cash rent due to us from Ardent was approximately $117.7$125.9 million, and the current aggregate contractual base rent (computed in accordance with GAAP) due to us from Ardent was approximately $126.0 million.

We also approximately $117.7 million. 

As of December 31, 2018,2020, we leased 29 properties to Kindred pursuant to a master lease agreement. In November 2016, Kindred extended the lease term to 2025 for all of our LTACs operated by Kindred that were scheduled to mature in 2018 and 2020, at the current rent level.

The aggregate annual rent we receive under each Kindred master lease is referred to as “base rent.” Base rent escalates annually at a specified rate over the prior period base rent, contingent, in some cases, upon the satisfaction of specified facility revenue parameters. The annual rent escalator under the Kindred master lease for 25 properties is based on year-over-year changes in CPI, subject to a floor and cap, and is 2.7% for four properties. As of December 31, 2018,2020, the aggregate 20192021 contractual cash rent due to us from Kindred was approximately $125.6$130.4 million, and the current aggregate contractual base rent (computed in accordance with GAAP) due to us from Kindred was approximately $127.9$132.4 million. 

As of December 31, 2018,2020, Atria Sunrise and ESL,Sunrise, collectively, provided comprehensive property management and accounting services with respect to 334 consolidated seniors258 of the senior housing communities pursuant to long-term management agreements with us.in our senior living operations segment. Under these management agreements, the operators receive annual base management fees ranging from 4.5% to 7% of revenues generated by the applicable properties and, in some cases, additional management fees based on the achievement of specified performance targets. Our management agreements with Atria and ESL have initial terms expiring between 20232024 and 2027, and our management agreements with Sunrise have terms expiring between 2030 and 2038. In some cases, our management agreements include renewal provisions. See “NOTE 3—CONCENTRATION OF CREDIT RISK” of the Notes to Consolidated Financial Statements included in Part II, Item 8 of this Annual Report on Form 10-K.

Because Atria Sunrise and ESLSunrise manage our properties in exchange for the receipt of a management fee from us, we are not directly exposed to the credit risk of our managers in the same manner or to the same extent as our triple-net tenants. However, we rely on our managers’ personnel, expertise, technical resources and information systems, proprietary information, good faith and judgment to manage our senior living operations efficiently and effectively. We also rely on our managers to set appropriate resident fees and otherwise operate our seniors housing communities in compliance with the terms of our management agreements and all applicable laws and regulations. Although we have various rights as the property owner under our management agreements, including various rights to terminate and exercise remedies under those agreements as provided therein, Atria’s, Sunrise’s or ESL’s failure, inability or unwillingness to satisfy its respective obligations under those agreements, to efficiently and effectively manage our properties or to provide timely and accurate accounting information with respect thereto could have a Material Adverse Effect on us. In addition, significant changes in Atria’s, Sunrise’s or ESL’s senior management or equity ownership or any adverse developments in their businesses or financial condition could have a Material Adverse Effect on us. See “Risk Factors—Risks Arising from Our Business—The properties managed by Atria, SunriseBusiness Operations and ESL account for aStrategy Risk—A significant portion of our revenues and operating income; adverse developments in Atria’s, Sunrise’s or ESL’s businessincome is dependent on a limited number of tenants and affairs or financial condition could have a Material Adverse Effect on usmanagers, including Brookdale Senior Living, Ardent, Kindred, Atria and Sunrise.” and “—We have rights to terminate our management agreements with Atria, Sunrise and ESL in whole or with respect to specific properties under certain circumstances, and we may be unable to replace Atria, Sunrise or ESL if our management agreements are terminated or not renewed” included in Part I, Item 1A of this Annual Report on Form 10-K.Report.

Competition

We believeprovide a unique environment that relationsoffers opportunities for our team to use their professional skills, develop their talents and learn from each other as they build successful careers. We are committed to upholding human dignity and equal opportunity under the principles outlined in the United Nations’ Universal Declaration of Human Rights. Our Global Code of Ethics and Business Conduct, Vendor Code of Conduct and Human Rights Policy embed the responsibility to respect human rights in business functions across our operations as well as our supply chain.

Ventas has a long-standing commitment to Diversity, Equity and Inclusion (“DE&I”). We have established a DE&I framework centered around five key pillars of people, culture, investment and financial, changing our society and improving our communities and celebrating our commitments. Development and execution of the DE&I framework is a core component of our 2021 short-term incentive program. Additionally, we incorporated a metric focused on improving the Company’s representation of women employees into our 2020-2022 long-term equity incentive program, to further drive progress and accountability. As of December 31, 2020, our workforce is. As of December 31, 2020, our workforce is 52% male and 48% female, with our employeesBoard of Directors being 36% female.

Ventas recognizes that sustainable practices and resilience are positive.essential to delivering superior long-term results. Our integrated approach to Environment, Social and Governance (“ESG”) principles animates our actions, decisions and processes. In 2018, we conducted an in-depth ESG prioritization (a “materiality assessment”) using the Global Reporting Initiative (GRI) framework, from which we organized the eight topics identified into three strategic pillars: People, Performance, and Planet. This approach integrates ESG principles throughout our business, ensures focus and reporting on key issues and motivates our daily efforts.

Insurance

We maintain or require in our lease, management and other agreements that our tenants, operators and managers or other counterparties maintain all applicable lines ofcomprehensive insurance coverage on our properties and their operations. Weoperations with terms, conditions, limits and deductibles that we believe that the amount and scope of insurance coverage provided by our policies and the policies required to be maintained by our tenants, operators and managers are customary for similarly situated companies in each industry and we frequently review our industry. Although we regularly monitor our tenants’, operators’insurance programs and managers’ compliance with their respectiverequirements. The insurance requirements, we cannot assure you that they will maintain the required insurance coverages, and any failure, inability or unwillingness by our tenants, operators and managers to do so could have a Material Adverse Effect on us. We also cannot assure you that we will continue tomaintain or require may take the same levelsform of commercial insurance, coverage under our lease, management and other agreements, that suchcaptive insurance coverage will be available at a reasonable cost in the future or that the policies maintained will fully cover all losses related to our properties upon the occurrence of a catastrophic event, nor can we assure you of the future financial viability of the insurers.self-insurance.

We maintain the property insurance for substantially all ofproperties in our office and senior living operations segment. We also maintain liability insurance for certain office properties, as well as the general and professional liability insurance for our seniorscertain senior housing communities and related operations managed by Atria and ESL.in our senior living operations segment. However, Sunrise maintainssome senior housing managers maintain the general and professional liability insurance for our seniorssenior housing communities and related operations that it managesthey manage in accordance with the terms of our management agreements. Under our management agreements with Sunrise, we may elect, on an annual basis, whether we or Sunrise will bear responsibility for maintaining the required insurance coverage for the applicable properties, but the costs of such insurance are facility expenses paid from the revenues of those properties, regardless of who maintains the insurance.

Through our office operations, we provide engineering, construction and architectural services in connection with new development projects, and anywe maintain and cause tenants, contractors, design construction or systems failures relatedprofessionals and other parties involved with such services to the properties we develop could result in substantial injury or damage to our clients or third parties. Any such injury or damage claims may arise in the ordinary coursemaintain property and may be assertedliability insurance with respect to ongoing or completed projects. Although we maintain liabilitythose activities.

In May 2020, the Company formed a wholly owned captive insurance to protect us against these claims, if any claim results in a loss, we cannot assure you that our policy limits would be adequate to cover the loss in full. If we sustain losses in excess of ourcompany, which provides insurance coverage we may be required to payfor losses below the differencedeductible and we could

Additional Information

We maintain a website at www.ventasreit.com. The information on our website is not incorporated by reference in this Annual Report, on Form 10-K, and our web address is included as an inactive textual reference only.

We make available, free of charge, through our website our Annual Report, on Form 10-K, Quarterly Reports on Form 10-Q, Current Reports on Form 8-K and amendments to those reports filed or furnished pursuant to Section 13 or 15(d) of the Exchange Act as soon as reasonably practicable after we electronically file such material with, or furnish it to, the SEC. In addition, our Guidelines on Governance, our Global Code of Ethics and Business Conduct (including waivers from and amendments to that

GOVERNMENTALGOVERNMENT REGULATION

United States Healthcare Regulation, Licensing and Enforcement

OurWe, along with our tenants, operatorsborrowers, and managers in the United States, are typically subject to or impacted by extensive and complex federal, state and local healthcare laws and regulations, including laws and regulations relating to quality of care, licensure and certificatecertificates of need (“CON”), conduct of operations, government reimbursement, such as Medicare and Medicaid, fraud and abuse, practices, qualifications of personnel, appropriateness and classification of care, adequacy of plant and equipment, and otherdata security and privacy. Although the effects of these laws and regulations governingon our business are typically indirect, some of these laws and regulations apply directly to us and the operation ofsenior housing communities in our senior living operations segment,

Violating these healthcare fraud and abuse laws and regulations may result in criminal and civil penalties, such as punitive sanctions, damage assessments, monetary penalties, imprisonment, denial of Medicare and Medicaid payments, and exclusion from the Medicare and Medicaid programs. The responsibility for enforcing theseThese laws and regulations lies withare enforced by a variety orof federal, state and

Regulation Impacting Life Science, Research and Innovation Centers

In 2016, we enteredWe lease a number of our assets to tenants in the life science, research and innovation sector. These tenants consist of university-affiliated organizations and other private sector through the acquisitions of substantially all of the university affiliated research and innovation real estate assets of Wexford Science & Technology, LLC from affiliates of Blackstone Real Estate Partners VIII, L.P. The research and innovationcompanies. These tenants of these assets are largely university-affiliated organizations. These university-affiliated research and innovation tenants aremay be dependent on private investors, the federal government or other sources of funding to varying degrees.support their activities. Creating a new pharmaceutical product or medical device requires substantial investments of time and capital, in part because of the extensive regulation of the healthcare industry; it also entails considerable risk of failure in demonstrating that the product is safe and effective and in gaining regulatory approval and market acceptance. Therefore, our tenants in the life science, research and innovation industry face high levels of regulation, expense and uncertainty. See “Risk Factors—Environmental, Economic and Market Risks—Our life science, R&I tenants face unique levels of regulation, expense and uncertainty.” included in Part I, Item 1A of this Annual Report.

Some of our research and innovation tenants require significant outlays of funds for the research, development and clinical testing of their products and technologies. If private investors, the federal government or other sources of funding are unavailable to support such activities, a tenant’s research and innovation operation may be adversely affected or fail. Further, the research, development, clinical testing, manufacture and marketing of some of our tenants’ products requires federal, state and foreign regulatory approvals which may be costly or difficult to obtain. Even after a research and innovation tenant gains regulatory approval and market acceptance for a product, the product may still present significant regulatory and liability risks, including, among others, the possible later discovery of safety concerns, competition from new products and the expiration of patent protection for the product. Our tenants with marketable products may be adversely affected by healthcare reform and government reimbursement policies, including changes under the current presidential administration or by private healthcare payors. Likewise,

We elected to be taxed as a REIT under Sections 856 through 860 of the Internal Revenue Code (the “Code”), commencing with our tenants maytaxable year ended December 31, 1999. Provided we qualify for taxation as a REIT, we generally will not be unablerequired to adequately protect their intellectual propertypay U.S. federal corporate income taxes on our REIT taxable income that is currently distributed to our stockholders. This treatment substantially eliminates the “double taxation” that ordinarily results from investment in a C corporation. We will, however, be required to pay U.S. federal income tax in certain circumstances.

We believe that we have been organized and have operated in a manner that has allowed us, and will continue to allow us, to satisfy conditions (1) through (7) inclusive, during the relevant time periods, and we intend to continue to be organized and operate in this manner. However, qualification and taxation as a REIT depend upon our ability to meet the various qualification tests imposed under patent, copyrightthe Code, including through actual operating results, asset composition, distribution levels and diversity of stock ownership. Accordingly, no assurance can be given that we will be organized or trade secret laws. will be able to operate in a manner so as to qualify or remain qualified as a REIT.

If we lose our researchstatus as a REIT (currently or with respect to any tax years for which the statute of limitations has not expired), we will face serious tax consequences that will substantially reduce the funds available to satisfy our obligations, to implement our business strategy and innovation tenants’ businessesto make distributions to our stockholders for each of the years involved because:

In addition, in such event we would no longer be required to pay dividends to maintain REIT status, which could materially adversely affect the value of our business, results of operations and financial condition.common stock. See “Risk Factors—Our REIT Status Risks”.

Environmental Regulation

However, these complex federal and state statutes, and their enforcement, involve a myriad of regulations, many of which involve strict liability on the part of the potential offender. Some of these federal and state statutes may directly impact us. Under various federal, state and local environmental laws, ordinances and regulations, an owner of real property we are subject to various federal, state and local laws and regulations regarding environmental, health and safety matters.

With respect to our properties that are operated or managed by third parties, we may be held primarily or jointly and severally liable for costs relating to the investigation and clean-upcleanup of any property from which there is or has been an actual or threatened release of a regulated material and any other affected properties, regardless of whether we knew of or caused the release. Such costs typically are not limited by law or regulation and could exceed the property’s value. In addition, we may be liable for certain other costs, such as governmental fines and injuries to persons, property or natural resources, as a result of any such actual or threatened release. See “Risk Factors-Risks Arising from Factors—Our Business-We could incur substantialBusiness Operations and Strategy Risks—Our operating assets may expose us to various operational risks, liabilities and claims that could adversely affect our ability to generate revenues or increase our costs if anyand could adversely affect our business, financial condition and results of our properties are found to be contaminated with hazardous substances or we become involved in any environmental disputes”operations.” included in Part I, Item 1A of this Annual Report on Form 10-K.Report.

Under the terms of our lease, management and other agreements, we generally have a right to indemnification by the tenants operators and managers of our properties for any contamination caused by them. However, we cannot assure you that our tenants, operators and managers will have the financial capability or willingness to satisfy their respective indemnification obligations to us, and any failure, inability or unwillingness to do so may require us to satisfy the underlying environmental claims.

In general, we have also agreed to indemnify our tenants and operatorsmanagers against any environmental claims (including penalties and clean-upcleanup costs) resulting from any condition arising in, on or under, or relating to, the leased properties at any time before the applicable lease commencement date. With respect to our senior living operating portfolio, we have agreed to indemnify our managers against any environmental claims (including penalties and clean- upcleanup costs) resulting from any condition on those properties, unless the manager caused or contributed to that condition.

ITEM 1A.    Risk Factors

This section discusses the most significantmaterial factors that affect our business, operations and financial condition. It does not describe all risks and uncertainties applicable to us, our industry or ownership of our securities. If any of the following risks, or any other risks and uncertainties that are not addressed below or that we have not yet identified, actually occur, we could be materially adversely affected and the value of our securities could decline.

We have grouped these risk factorsAs set forth below, we believe that the risks we face generally fall into three generalthe following categories:

Risks arising fromThe COVID-19 pandemic and measures to prevent its spread have materially negatively impacted our capital structure;businesses in a number of ways and

Additionally, across our property types, the impact of the COVID-19 pandemic creates a heightened risk of tenant, borrower, manager or other adverseobligor bankruptcy or insolvency due to factors such as decreased occupancy, medical practice disruptions resulting from stay-at-home orders, increased health and safety and labor expenses or litigation resulting from developments related to the COVID-19 pandemic. In addition to the risks associated with such events accelerationelsewhere in these risk factors, various federal, state and local governments have enacted, and may continue to enact, laws regulations and moratoriums or take other actions that could limit our ability to evict tenants as a result of its indebtedness, impairmentthe COVID-19 pandemic. Although many of its continued accessthese moratoriums are expected to capital,be temporary in nature, they may be in place for a significant period of time until the enforcement of default remedies by its counterparties, or the commencement of insolvency proceedings by or against it under the U.S. Bankruptcy Code, any one or a combination of which indirectly couldCOVID-19 pandemic subsides. While we generally have a Material Adverse Effect on us.

The COVID-19 pandemic and reactions to it have also adversely affected the U.S. economy and global financial markets and, in the eventlonger term, could result in a global economic downturn and a recession, or inflation, which may, in turn negatively impact our results of defaultoperations. The COVID-19 pandemic has increased, and may continue to increase, the magnitude of many of the other risks described herein.

The trajectory and future impact of the COVID-19 pandemic remains highly uncertain. The extent of the pandemic’s continuing and ultimate effect on our operational and financial performance will depend on a variety of factors, including the obligations owingspeed at which available vaccines can be successfully deployed; the rate of acceptance of available vaccines, particularly among the residents and staff in our senior housing communities; the impact of new variants of the virus and the effectiveness of available vaccines against those variants; ongoing clinical experience, which may differ considerably across regions and fluctuate over time; and on other future developments, including the ultimate duration, spread and intensity of the outbreak, the availability of testing, the extent to us, we may determine not to do so if we believe that enforcementwhich governments impose, rollback or re-impose preventative restrictions and the availability of our rights would be more detrimentalongoing government financial support to our business, than seeking alternative approaches.

In response to terminate our management agreements with Atria, Sunrisethe COVID-19 pandemic, the CARES Act, the PPPHCE Act, and ESL in wholethe CAA authorize a total of $178 billion to be distributed to healthcare providers through the Provider Relief Fund, which is administered by HHS. These grants are intended to reimburse eligible providers for healthcare-related expenses or with respectlost revenues attributable to specific properties under certain circumstances,COVID-19. Recipients are not required to repay distributions from the Provider Relief Fund, provided that they attest to and we may be unable to replace Atria, Sunrise or ESL if our management agreements are terminated or not renewed.

HHS began distributing Provider Relief Fund grants in April 2020 and has made grants available to various provider groups in phases. We applied for grants under Phase 2 and Phase 3 of Sunrisethe Provider Relief Fund on behalf of the assisted living communities in our senior living operations segment and may apply for additional grants in the future. While we have received all amounts under our Phase 2 applications, and have begun to make cure paymentsreceive amounts under our Phase 3 applications, there can be no assurance that all our remaining applications will be approved or that additional grants will ultimately be received in full or in part. Any grants that are ultimately received and retained by us are not expected to us, and uponfully offset the occurrence of certain other events or the existence of certain other conditions.

Due to the recent enactment of the CARES Act, and other enacted legislation, there is still a high degree of uncertainty surrounding their implementation. Further, the federal government is considering additional financial measures, federal agencies continue to issue related regulations and guidance, and the public health emergency continues to evolve. It is difficult to predict the extent to which anticipated ongoing negative effects of the COVID-19 pandemic on us and our tenants are required to continue to perform alland

Our Business Operations and circumstances, we may have the right to consent to, or otherwise exercise rights and remedies, including termination rights, on account of, a competitor’s investment in, a change of control of, or other transactions impacting a tenant, operator or manager. In deciding whether to exercise our rights and remedies, including termination rights, we assess numerous factors, including legal, contractual, regulatory, business and other relevant considerations. In addition, in connection with any change of control of a tenant, operator or manager, the tenant’s, operator’s or manager’s management team may change, which could lead to a change in the tenant’s, operator’s or manager’s strategy or adversely affect the business of the tenant, operator or manager, either of which could have a Material Adverse Effect on us.Strategy Risks

We are dependent on the capital markets and financial condition.

In addition, increased inflation may have a pronounced negative impact on the interest expense we pay in connection with our outstanding indebtedness, andin our general and administrative expenses, as these costs could increase at a rate higher than our rents.

Our senior housing tenants and managers may also rely on reimbursements from governmental programs for a portion of the revenues from certain properties. Changes in reimbursement policies and acquisitions of,other governmental regulation, that may result from actions by Congress or executive orders, may result in reductions in our tenants’ or managers’ revenues, operations and cash flows and affect our tenants’ or managers’ ability to meet their obligations to us. In addition, failure to comply with reimbursement regulations or other laws applicable to healthcare providers could result in penalties, fines, litigation costs, lost revenue or other consequences, which could adversely impact our tenants’ ability to make contractual rent payments to us under a triple-net lease or our developmentcash flows from operations under a management arrangement.

Our tenants and managers have, and may continue to seek to, offset losses by obtaining funds under the recently adopted CARES Act or redevelopmentother similar legislative initiatives at the state and local level. It is indeterminable when or if these

As of December 31, 2020, Atria and Sunrise, collectively, managed 258 of our consolidated senior housing communities pursuant to long-term management agreements. Additionally, as of December 31, 2020, our three largest tenants, Brookdale Senior Living, Ardent and healthcareKindred leased from us 121 properties, 12 properties and 32 properties respectively. These properties represent a substantial portion of our portfolio, based on their gross book value, and account for a significant portion of our revenues and NOI.

We depend on Brookdale Senior Living, Ardent and Kindred to pay all property-related expenses, including maintenance, utilities, repairs, taxes, insurance and capital expenditures, and to comply with the terms of the mortgage financing documents, if any, affecting the properties they lease from us. We cannot assure you that they will have sufficient assets, income and access to financing to enable them to satisfy their obligations to us, and any failure, inability or unwillingness by them to do so could adversely affect our business, financial condition and results of operations. In addition, any failure by any one of Brookdale Senior Living, Ardent or Kindred to conduct effectively its operations or to maintain and improve the properties it leases from us could adversely affect its business reputation and its ability to attract and retain patients or residents in such properties, which could in turn adversely affect our business, financial condition and results of operations. These tenants have agreed to indemnify, defend and hold us harmless from and against various claims, litigation and liabilities arising in connection with their respective businesses. We cannot assure you that they will have sufficient assets, income, access to financing and insurance coverage to enable them to satisfy those obligations.

Our tenants may not renew their leases with us, and our managers may not renew their management agreements with us, beyond their current terms. Our leases and management agreements also provide us, our tenants and our managers with termination rights in certain circumstances. If our leases or management agreements are not renewed or are otherwise terminated, we would attempt to reposition those properties with another tenant or manager, as applicable. We may not be successful in identifying suitable replacements or entering into leases, management agreements or other arrangements with new tenants or managers on a timely basis or on terms as favorable to us as our current leases or management agreements, if at all, and consummating these transactionswe may be required to fund certain expenses and obligations (e.g., real estate taxes, debt costs and maintenance expenses) to preserve the value of, and avoid the imposition of liens on, our properties while they are being repositioned.

The success of our business strategydepends, in part, on the leadership and performance of our executive management team and key employees. Failure to attract, retain and motivate highly qualified employees, or failure to develop and implement a viable succession plan, could result in inadequate depth of institutional knowledge, an ineffective culture or lack of certain skill sets, significantly impacting our future performance and adversely affecting our business. Competition for talented employees is intense, and we cannot assure you that we will retain our key officers and employees or that we will be able to continueattract and retain other highly qualified individuals in the future. COVID-19 could also negatively affect the health, availability and productivity of our current personnel and could impact our ability to expandrecruit and diversifyattract new employees and retain current employees, particularly as remote work arrangements and their impact on the market for talent remains uncertain. In addition, while we have long-term compensation plans designed to retain our portfolio through accretive acquisition, investment, developmentsenior executives, if our retention and redevelopment opportunitiessuccession plans are not effective, or if we lose any one or more of our key officers and employees, our business could be adversely affected.

We invest in a variety of assets classes in healthcare real estate, including senior housing, R&I and healthcare properties. Our execution of this strategy by successfully identifying, securing and consummating beneficial transactions is made more challenging by increased competition andWhile we endeavor to invest in a diversified portfolio, there can be affected by many factors, includingno assurance that in a particular economic or operational environment that all assets will perform equally well or that our relationships with currentbalance sheet will be appropriately balanced. Each of our asset classes are subject to their own dynamics and prospective clients, our ability to obtain debttheir own specific operational, financial, compliance, regulatory and equity capital at costs comparable tomarket risks.

In addition, we are exposed to the risks inherent in concentrating our investments in real estate. Real estate investments are relatively illiquid, and our ability to quickly sell or exchange our properties in response to changes in economic or other conditions is limited. In the event we market any of our properties for sale, the value of those properties and our ability to sell and other contractual counterparties. Our competitors for these opportunities include other healthcare REITs,at prices or on terms acceptable to us could be adversely affected by a downturn in the real estate partnerships,industry. In addition, transfers of healthcare providers, healthcare lenders and other investors, including developers, banks, insurance companies, pension funds, government-sponsored entities and private equity firms, some of whom may have greater financial resources and lower costs of capital than we do. See “Business—Competition” included in Part I, Item 1 of this Annual Report on Form 10-K. If we are unsuccessful at identifying and capitalizing on investment, acquisition, development and redevelopment opportunities, our growth and profitabilityreal estate may be subject to regulatory approvals that are not required for transfers of other types of commercial real estate. We cannot assure you that we will recognize the full value of any property that we sell for liquidity or other reasons, and the inability to respond quickly to changes in the performance of our investments could adversely affected.affect our business, financial condition and results of operations.

We have made and expect to continue to make significant acquisitions and investments as part of our overall business strategy. Investments in and acquisitions of seniors housing and healthcare propertiesreal estate entail risks associated with real estate investments generally, including risks that the investment will not achieve expected returns, that the cost estimates for necessary property improvements will prove inaccurate or that thea tenant, operatorborrower or manager will fail to meet performance expectations. Investments outside the United States raise legal, economic and market risks associated with doing business in foreign countries, such as currency exchange fluctuations, costly regulatory requirements and foreign tax risks. Domestic and international real estate development and redevelopment projects present additional risks, including construction delays or cost overruns that increase expenses, the inability to obtain required zoning, occupancy and other governmental approvals and permits on a timely basis, and the incurrence of significant costs prior to completion of the project. Furthermore, healthcare real estate properties are often highly customized, and the development or redevelopment of such properties may require costly tenant-specific improvements. As a result, we cannot assure you that we will achieve the economic benefit we expect from acquisition, investment, development and redevelopment opportunities.

We cannot assure you that weour acquisitions, developments, redevelopments and other investments will be able to integrate acquisitions and investmentssuccessful or meet our expectations without encountering difficulties or that any such difficulties will not have a Material Adverse Effect on us.

An important part of our business strategy is to continue to expand and diversify our portfolio, directly or indirectly with third parties, through accretive acquisition, investment, development and redevelopment activities in domestic and international healthcare real estate. Our execution of this strategy by successfully identifying, securing and consummating beneficial transactions is made more challenging by increased competition and can be materiallyaffected by many factors, including our

In addition,For example, we recently expanded into R&I and life sciences. When expanding into areas that are new to us, we face numerous risks and uncertainties, including risks associated with (i) the required investment of capital and other resources; (ii) the possibility that we have now,insufficient expertise to engage in such activities profitably or without incurring inappropriate amounts of risk; (iii) the diversion of management’s attention from our other businesses; (iv) the increasing demands on or issues related to operational and may have in the future, certain surviving indemnification obligations in favor of third parties under the terms of acquisition agreements tomanagement systems and controls; (v) compliance with additional legal or regulatory requirements with which we are a party.  Most of these indemnification obligations will be capped as to amountnot familiar; and survival period, and we do not believe that these obligations will be material in(vi) the aggregate.  However, there can be no assurances as to the ultimate amount of such obligations or whether such obligations will have a Material Adverse Effect on us.

These ventures involve risks not present with respect to our wholly owned properties, including the following:

If any of the risks described above occur, our development and redevelopment projects may not yield anticipated returns, which could adversely affect our business, financial condition and results of operationsoperations.

Our operating assets expose usWe lease our properties to unaffiliated tenants or operate them through independent third-party managers. We are also a direct or indirect lender to various operational risks, liabilitiestenants and claimsmanagers. We have limited control over the success or failure of our tenants’, borrowers’ and managers’ businesses, and, at any time, a tenant, borrower or manager may experience a downturn in its business that could adversely affectweakens its financial condition. If that happens, the tenant, borrower or manager may fail to make its payments to us when due. Although our abilitylease, loan and management agreements give us the right to generate revenues or increase our costs and could have a Material Adverse Effect on us.

A downturn in any one of our tenants’, borrowers’ or CPI does not increase, our growth and profitabilitymanagers’ businesses could ultimately lead to its bankruptcy if it is unable to timely resolve the underlying causes, which may be hindered. If strong economic conditions resultlargely outside of its control. Bankruptcy and insolvency laws afford certain rights to a party that has filed for bankruptcy or reorganization that may render certain of our rights and remedies unenforceable, or, at the least, delay our ability to pursue such rights and remedies and realize any recoveries in significant increasesconnection therewith. For example, we cannot evict a tenant solely because of its bankruptcy filing. Additionally, a debtor-lessee may reject our lease in CPI, but the escalations under our leases are capped, our growtha bankruptcy proceeding, and profitabilityany claim we have for unpaid rent might not be paid in full. We also may be limited.required to fund certain expenses and obligations (e.g., real estate taxes, debt costs and maintenance expenses) to preserve the value of our properties, avoid the imposition of liens on our properties or transition our properties to a new tenant or manager.

Our investments in MOBs, R&I buildings and facilities as well as other properties may be made through leasehold interests in the land on which the buildings are located, leases of air rights for the space above the land on which the buildings are located, or other similar restrictive arrangements. Many of these ground lease, air rights and other restrictive agreements impose significant limitations on our uses of the subject properties, restrict our ability to sell or otherwise transfer our interests in the properties or restrict the leasing of the properties. These restrictions may limit our ability to timely sell or exchange the properties, impair the properties’ value or negatively impact our ability to find suitable tenants for the properties. In addition, we could lose our interests in the subject properties if the ground lease, air rights or other restrictive agreements are breached by us or terminated.

The oversupply of healthcare real estate could adversely affect our business. In many jurisdictions, limited barriers to entry could lead to the development of new properties that outpaces demand across our various asset classes. If existing supply and development collectively outpaces demand for those assets in the markets in which our properties are located, those markets may be unable to successfully foreclose on the collateral securing our loansbecome saturated and other investments,we could experience decreased occupancy, reduced operating margins and even if we are successful in our foreclosure efforts, we may be unable to successfully sell any acquired equity interests or reposition any acquired properties,lower profitability, which could adversely affect our ability to recover our investments.

We are exposed to general economic conditions, local, regional, national and international economic conditions and other events and occurrences that affect the markets in which we own properties. Our operating performance is impacted by the economic conditions of certainthe specific markets in which we have concentrations of properties and could be adversely affected if conditions become less favorable in any such markets. For example, a shortage of skilled workers in a particular region, including nurses or other trained personnel, may force our third-party managers to enhance their pay and benefits package to compete effectively for such personnel, but such managers may not be able to offset these added costs by increasing the rates charged to residents, which may result in less revenue to our business.

A substantial portion of our tenantsvalue is derived from properties in California, New York, Texas, Pennsylvania and operators, which could affect adversely their ability to comply with the terms of our leasesIllinois, and haveas a Material Adverse Effect on us.

Our tenants, who are providers ofborrowers and managers include senior housing operators, hospitals, post-acute facilities and other healthcare services; however, if this trend significantlysystems, medical offices and adversely affects their profitability, it could in turn negatively affect their abilitylife sciences and willingness to comply with the terms of their leases with us and or renew those leases upon expiration, which could have a Material Adverse Effect on us.

Our MOB operationsMOBs and other properties that serve the healthcare industry depend on the competitiveness and financial viability of the hospitals on or near whosethe campuses where our MOBsproperties are located and their ability to attract physicians and other healthcare-related clients to our MOBs.properties. The viability of these hospitals, in turn, depends on factors such as the quality and mix of healthcare services provided, competition for patients, physicians and physician groups, demographic trends in the surrounding community, market position and growth potential as well as the ability of the affiliated health systems to provide economies of scale and access to capital. If a hospital on or near whosethe campus where one of our MOBsproperties is located fails or becomes unable to meet its financial obligations, and if an affiliated health system is unable to support that hospital, thethat hospital may be unable to compete successfully or could be forced to close or relocate, which could adversely impact its ability to attract physicians and other healthcare-related clients. Because we rely on proximity to and affiliations with hospitals to create leasing demand in our MOBs,properties, a hospital’s inability to remain competitive or financially viable, or to attract physicians and physician groups, could materially adversely affect our MOB operations and have a Material Adverse Effect on us.

ResearchOur life science, R&I tenants develop and innovationsell products and services in an industry that is characterized by rapid and significant changes, evolving industry standards and uncertainty over the implementation of new healthcare reform legislation, which may cause them to lose competitive positions and adversely affect their operation. These tenants, particularly those involved in developing and marketing pharmaceutical products, are subject to certain unique risks, including the following:

TheAdditionally, the research and development, clinical testing, manufacture and marketing of some of our tenants’ products require federal, state and foreign regulatory approvals. The approval process is typically long, expensive and uncertain. Even if our tenants have sufficient funds to seek approvals, one or all of their products may fail to obtain the

We cannot assure you that any of our life science, R&I tenants in the research and innovation industry will be successful in their businesses. If our tenants’ businesses are adversely affected, theyAny tenant that is unable to avoid, or sufficiently mitigate, the risks described above may have difficulty making rental payments or satisfying its other lease obligations to us or may have difficulty maintaining the value of our investment, which could materially adversely affect our business, results of operations and financial condition.

The seniors housing and healthcare industries have experienced and may continue to implementexperience consolidation, including among owners of real estate, tenants and care providers. In connection with any change of control of a captivetenant, borrower or self-insurance program,manager, such tenant’s, borrower’s or manager’s strategy, financial condition, management team or real estate needs may change, any large fundedof which could adversely affect our relationship with such party and unfunded generalour revenues and professional liability expenses incurredresults of operations. In addition, a competitor’s investment in one of our tenants, borrowers or managers could have a Material Adverse Effect on us.

Certain of our properties are located in areas particularly susceptible to revenue loss, cost increase or damage caused by catastrophic or extreme weather and other natural events, including fires, snow or ice storms, windstorms or hurricanes, earthquakes, flooding or other severe weather. These adverse weather and natural events could cause substantial damages or losses to our properties which could exceed our or our tenants’, operators’ andborrowers’ or managers’ property insurance coverage. Operationally, such events could cause a major power outage, leading to a disruption of our systems and operations. In the event of a loss in excess of insured limits, we could lose our capital invested in the affected property, as well as anticipated future revenue from that property. Any such loss could materially and adversely affect our business, and our financial condition and results of operations. Climate change may also have indirect effects on our business by increasing the cost of (or making unavailable) property insurance on terms we find acceptable.

To the extent that significant changes in the climate occur in areas where our properties are located, we may experience extreme weather and changes in precipitation and temperature, all of which may result in physical damage to or a decrease in demand for properties located in these areas or affected by these conditions. Should the impact of climate change be material in nature, including destruction of our properties, or occur for lengthy periods of time, our business, financial condition or results of operations may be adversely affected.

In addition, changes in federal and state legislation and regulation on climate change could result in increased capital expenditures to improve the energy efficiency of our existing properties and could also require us to spend more on our new development properties without a corresponding increase in revenue.

As of December 31, 2018,2020, we had approximately $10.7$11.9 billion of outstanding indebtedness. The instruments governing our existing indebtedness permit us to incur substantial additional debt, including secured debt, and we may satisfy our capital and liquidity needs through additional borrowings. A high level of indebtedness would require us to dedicate a substantial portion of our cash flow from operations to the payment of debt service, thereby reducing the funds available to

In addition, from time to time, we mortgage certain of our properties to secure payment of indebtedness. If we are unable to meet our mortgage payments, then the encumbered properties could be foreclosed upon or transferred to the mortgagee with a resulting loss of income and asset value.

We receive a significant portion of our revenues by leasing assets under long-term triple-net leases that generally provide for fixed rental rates subject to annual escalations, while certain of our debt obligations are floating rate obligations with interest and related payments that vary with the movement of LIBOR, Bankers’ Acceptance or other indexes. The generally fixed rate nature of a significant portion of our revenues and the variable rate nature of certain of our debt obligations create interest rate risk. Although our operating assets provide a partial hedge against interest rate fluctuations, if interest rates rise, the costs of our existing floating rate debt and any new debt that we incur would increase. These increased costs could reduce our profitability, impair our ability to meet our debt obligations, or increase the cost of financing our acquisition, investment, development and redevelopment activity. An increase in interest rates also could limit our ability to refinance existing debt upon maturity or cause us to pay higher rates upon refinancing, as well as decrease the amount that third parties are willing to pay for our assets, thereby limiting our ability to promptly reposition our portfolio in response to changes in economic or other conditions.

We may seek to manage our exposure to interest rate volatility with hedging arrangements that involve additional risks, including the risks that counterparties may fail to honor their obligations under these arrangements, that these arrangements may not be effective in reducing our exposure to interest rate changes, that the amount of income we earn from hedging transactions may be limited by federal tax provisions governing REITs, and that these arrangements may cause us to pay higher interest rates on our debt obligations than otherwise would be the case. Moreover, no amount of hedging activity can fully insulate us from the risks associated with changes in interest rates. Failure to hedge effectively against interest rate risk, if we choose to engage in such activities, could adversely affect our business, financial condition and results of operations and financial condition.operations.

The terms of the instruments governing our existing indebtedness require us to comply with certain customary financial and other covenants, such as maintaining debt service coverage, leverage ratios and minimum net worth requirements. Our continued ability to incur additional debt and to conduct business in general is subject to our compliance with these covenants, which limit our operational flexibility. Breaches of these covenants could result in defaults under the applicable debt instruments and could trigger defaults under any of our other indebtedness that is cross-defaulted against such instruments, even if we satisfy our payment obligations. In addition, covenants contained in the instruments governing our subsidiaries’ outstanding mortgage indebtedness may restrict our ability to obtain cash distributions from such subsidiaries for the purpose of meeting our debt service obligations. Financial and other covenants that limit our operational flexibility, as well as defaults resulting from our breach of any of these covenants, could adversely affect our business, financial condition and results of operations.

In our operating assets, including those in our senior living operations and office segments, we are generally responsible for all liabilities of such properties, including any lawsuits, investigations, claims and other legal or regulatory proceedings, other than those arising out of certain actions by our managers, such as those caused by gross negligence or willful misconduct. As a result, we have exposure to, among other things, professional and general liability claims, employment law claims and the associated litigation and other costs related to defending and resolving such claims. In our senior living operations in particular, if one of our managers fails to comply with applicable law or regulation, we may be deemed responsible, which could subject us to the imposition of civil, criminal and administrative penalties, including: the loss or suspension of accreditation, licenses or CONs; suspension of or non-payment for new admissions; denial of reimbursement; fines; suspension, decertification, or exclusion from federal and state healthcare programs; or facility closure.

In certain circumstances, our tenants or managers may be contractually obligated to indemnify, defend and hold us harmless in whole or in part with respect to certain actions, legal or regulatory proceedings. In addition, third parties from whom we acquired certain of our assets and, in some cases, their affiliates may be required by the terms of the related conveyance documents to indemnify, defend and hold us harmless against certain actions, investigations and claims related to the acquired assets and arising prior to our ownership or related to excluded assets and liabilities. In some cases, a Material Adverse Effectportion of the purchase price consideration is held in escrow for a specified period of time as collateral for these indemnification obligations. We cannot assure you that these third parties will be able to satisfy their defense and indemnification obligations to us or that any purchase price consideration held in escrow will be sufficient to satisfy claims for which we are entitled to indemnification.

We and our tenants, borrowers and managers are subject to or impacted by extensive and frequently changing federal, state, local and international laws and regulations. For example, the healthcare industry is subject to laws and regulations that relate to, among other things, licensure and CON, conduct of operations, ownership of facilities, construction of new facilities and addition of equipment, governmental reimbursement programs, such as Medicare and Medicaid, allowable costs, services, prices for services, qualified beneficiaries, appropriateness and classification of care, patient rights, resident health and safety, data privacy and security laws, wage and hour laws, fraud and abuse and financial and other arrangements that may be entered into by healthcare providers. We generally hold the applicable healthcare licenses and enroll in applicable government healthcare programs on behalf of the properties in our senior living operations segment, which subjects us to potential liability under certain of such related healthcare laws and regulations. See “Government Regulation—United States Healthcare Regulation, Licensing and Enforcement” included in Part I, Item 1 of this Annual Report. In addition, many of our R&I tenants

In certain cases, we and our tenants and managers may be subject to professional liability, general liability, employment, premise, privacy, environmental, unfair business practice and contracts claims brought by plaintiffs’ attorneys seeking significant damages and attorneys’ fees, some of which may not be insured or indemnified and some of which may result in significant damage awards. Due to the historically high frequency and severity of professional liability claims against senior housing and healthcare providers, the availability of professional liability insurance has decreased and the premiums on such insurance coverage remain costly. In addition, insurance for other claims such as wage and hour, certain environmental, privacy and unfair business practices may no longer be available, and the premiums on such insurance coverage, to the extent it is available, remain costly. As a result, insurance protection against such claims may not be sufficient to cover all claims against us or our tenants or managers and may not be available at a reasonable cost or otherwise on terms that provide adequate coverage. If we or our tenants and managers are unable to maintain adequate insurance coverage or are required to pay damages, we or they may be exposed to substantial liabilities and the adverse impact on our or our tenants’ and managers’ respective financial condition, results of operations and cash flows could be material, and could adversely affect our tenants’ and managers’ ability to meet their obligations to us.

Pursuant to the Sarbanes-Oxley Act of 2002, we are required to provide a report by management on internal control over financial reporting, including management’s assessment of the effectiveness of such control. Because of its inherent limitations, including the possibility of human error, the circumvention or overriding of controls, or fraud, effective internal controls over financial reporting may not prevent or detect misstatement and can provide only reasonable assurance with respect to the preparation and fair presentation of financial statements. If we fail to maintain the adequacy of our internal controls over financial reporting and our operating internal controls, including any failure to implement required new or improved controls as a REITresult of changes to our business or otherwise, or if we experience difficulties in their implementation, our business, financial condition and results of operations could be adversely affected and we could fail to meet our reporting obligations.

If we lose our status as a REIT (currently or with respect to any tax years for which the statute of limitations has not expired), we will face serious tax consequences that will substantially reduce the funds available to satisfy our obligations, to implement our business strategy and to make distributions to our stockholders for each of the years involved because:

In addition, in such event we would no longer be required to pay dividends to maintain REIT status, which could adversely affect the value of our common stock.

Qualification as a REIT involves the application of highly technical and complex provisions of the Internal Revenue Code of 1986, as amended (the “Code”) for which there are only limited judicial and administrative interpretations. The determination of factual matters and circumstances not entirely within our control, as well as new legislation, regulations, administrative interpretations or court decisions, may adversely affect our investors or our ability to remain qualified as a REIT for tax purposes. In order to maintain our qualification as a REIT, we must satisfy a number of requirements, generally including requirements regarding the ownership of our stock, requirements regarding the composition of our assets, a requirement that at least 95% of our gross income in any year must be derived from qualifying sources, and we must make distributions to our stockholders aggregating annually at least 90% of our net taxable income, excluding capital gains. Although we believe that we currently qualify as a REIT, we cannot assure you that we will continue to qualify for all future periods.

To comply with the 90% distribution requirement applicable to REITs and to avoid the nondeductible excise tax, we must make distributions to our stockholders. Such distributions reduce the funds we have available to finance our investment, acquisition, development and redevelopment activity and may limit our ability to engage in transactions that are otherwise in the best interests of our stockholders.

Although we do not anticipate any inability to satisfy the REIT distribution requirement, fromFrom time to time, we may not have sufficient cash or other liquid assets to do so.satisfy the REIT distribution requirements. For example, timing differences between the actual receipt of income and actual payment of deductible expenses, on the one hand, and the inclusion of that income and deduction of those expenses in arriving at our taxable income, on the other hand, or non-deductible expenses such as principal amortization or repayments or capital expenditures in excess of non-cash deductions may prevent us from having sufficient cash or liquid assets to satisfy the 90% distribution requirement.

To assist us in preserving our qualification as a REIT, our certificate of incorporation provides that if a person acquires beneficial ownership of more than 9.0% of our outstanding common stock or more than 9.9% of our outstanding preferred stock, the shares that are beneficially owned in excess of the applicable limit are considered “excess shares” and are automatically deemed transferred to a trust for the benefit of a charitable institution or other qualifying organization selected by our Board of Directors. The trust is entitled to all dividends with respect to the excess shares and the trustee may exercise all voting power over the excess shares. In addition, we have the right to purchase the excess shares for a price equal to the lesser of (i) the price per share in the transaction that created the excess shares or (ii) the market price on the day we purchase the shares, but ifshares. If we do not purchase the excess shares, the trustee of the trust is required to transfer the shares at the direction of our Board of Directors. These ownership limits could delay, defer or prevent a transaction or a change of control that might involve a premium price for our common stock or might otherwise be in the best interests of our stockholders.

Under the Code, no more than 20% of the value of the gross assets of a REIT may be represented by securities of one or more TRSs. This limitation may affect our ability to increase the size of our TRSs’ operations and assets, and there can be no assurance that we will be able to comply with the applicable limitation, or that such compliance will not adversely affect our business. Also, our TRSs may not, among other things, operate or manage certain health carehealthcare facilities, which may cause us to forgo investments we might otherwise make. Finally, we may be subject to a 100% excise tax on the income derived from certain transactions with our TRSs that are not on an arm's-length basis. We believe our arrangements with our TRSs are on arm's-length terms and intend to continue to operate in a manner that allows us to avoid incurring the 100% excise tax described above, but there can be no assurance that we will be able to avoid application of that tax.

The Tax Cuts and Jobs Act of 2017 (the “2017 Tax Act”) significantly changed the U.S. federal income taxation of U.S. businesses and their owners, including REITs and their stockholders. Changes made by the 2017 Tax Act that could affect us and our stockholders include:

SeniorsSenior Housing and Healthcare Properties

As of December 31, 2018,2020, we owned or managed through unconsolidated real estate entities approximately 1,200 properties (including properties owned through investments in unconsolidated entities and properties classified as held for sale), consisting of seniorssenior housing communities, medical office buildings (“MOBs”), life science, research and innovation centers, inpatient rehabilitation facilities (“IRFs”) and long-term acute care facilities (“LTACs”), and health systems and skilled nursing facilities (“SNFs”), and wesystems. We had 1913 properties under development, including five properties thatthree of which are owned by unconsolidated real estate entities. We believe that maintaining a balanced portfolio of high-quality assets diversified by investment type, geographic location, asset type, tenant/operator, revenue source and operating model makes us less susceptible to single-state regulatory or reimbursement changes, regional climate events and local economic downturns and diminishes the risk that any single factor or event could materially harm our business.

As of December 31, 2018,2020, we had $1.1$2.2 billion aggregate principal amount of mortgage loan and secured revolving construction credit facility indebtedness outstanding, secured by 6080 of our properties. Excluding those portions attributedthe portion of such indebtedness attributable to our joint venture partners, our share of mortgage loan and secured revolving construction credit facility indebtedness outstanding was $1.0$2.0 billion.

The following table provides additional information regarding the geographic diversification of our consolidated portfolio of properties as of December 31, 20182020 (excluding properties owned through investments in unconsolidated real estate entities and properties classified as held for sale).