The Board of Trustees (the "Board") of Senior Housing Properties Trust (the "Company," "we," "us" or "our") is furnishingThis proxy summary highlights information which may be provided elsewhere in this proxy statement and accompanying proxy card (or voting instruction form) to you in connection with the solicitation of proxies by the Board for the 2019 annual meeting of shareholdersProxy Statement. This summary does not contain all of the Company. The meeting will be held at Two Newton Place, 255 Washington Street, Suite 100, Newton, Massachusetts 02458 on Tuesday, May 21, 2019, at 9:30 a.m., Eastern time,information that you should consider, and any adjournments or postponements thereof (the "2019 Annual Meeting"). Weyou should read the entire Proxy Statement carefully before voting. Page references are first making these proxy materials availablesupplied to shareholders on or about April 5, 2019.help you find further information in this Proxy Statement.

Only ownersELIGIBILITY TO VOTE

You can vote if you were a shareholder of record of common shares of beneficial interest of the Company ("Common Shares") as ofat the close of business on February 28, 2019,March 24, 2021, the record date for our 2021 Annual Meeting.

HOW TO CAST YOUR VOTE (Page 50)

You can vote by any of the meeting, are entitled to noticefollowing methods:

•

By Telephone or Internet.    All shareholders of andrecord can authorize a proxy to vote their shares by touchtone telephone by calling 1-800-690-6903, or through the internet at www.proxyvote.com, using the procedures and instructions described in your Notice Regarding the Availability of Proxy Materials or proxy card.



•

By Written Proxy.    All shareholders of record also can submit voting instructions by written proxy card. If you are a shareholder of record and receive a Notice Regarding the Availability of Proxy Materials, you may request a written proxy card by following the instructions included in the notice.



•

Electronically at our 2021 Annual Meeting.    All shareholders of record may vote electronically at the meeting andmeeting. Beneficial owners may vote electronically at any postponements or adjournments of the meeting. Holders of Common Shares are entitled to one vote for each Common Share held on the record date. On February 28, 2019, there were approximately 237,729,900 Common Shares issued and outstanding.

The mailing address of the Company's principal executive offices is Two Newton Place, 255 Washington Street, Suite 300, Newton, Massachusetts 02458.

IMPORTANT NOTICE REGARDING THE AVAILABILITY OF PROXY MATERIALS FOR THE
2019 ANNUAL MEETING TO BE HELD ON TUESDAY, MAY 21, 2019.

The Notice of 2019our 2021 Annual Meeting Proxy Statementif they have a legal proxy.

CORPORATE GOVERNANCE PRINCIPLES (Page 4)

We pride ourselves on continuing to observe and Annual Reportimplement best practices in our corporate governance.

SUSTAINABILITY (Page 7)

We have a long-standing commitment to Shareholders forour shareholders and stakeholders to conduct our business in an environmentally and socially responsible manner.

VOTING (Pages 1, 21, 35 and 46)

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PROPOSAL 1: ELECTION OF TRUSTEES (Page 21)

Upon the recommendation of our Nominating and Governance Committee, our Board has nominated Lisa Harris Jones as an Independent Trustee and Jennifer F. Francis (Mintzer) ("Jennifer F. Francis") as a Managing Trustee. Presented below is the expected composition of our Board immediately following our 2021 Annual Meeting, assuming the election of Jennifer F. Francis and Lisa Harris Jones and the expiration of Jennifer B. Clark's term as a Trustee.

PROPOSAL 2: ADVISORY VOTE TO APPROVE EXECUTIVE COMPENSATION (Page 35)

COMPENSATION DISCUSSION AND ANALYSIS (Page 36)

Our compensation structure is unique because of our relationship with our manager, The RMR Group LLC ("RMR LLC"). Our business management agreement with RMR LLC is designed to incentivize RMR LLC to provide the highest quality services to us. Our Compensation Committee believes that our executive compensation program is appropriately designed to incentivize strong performance over the long term.

PROPOSAL 3: RATIFICATION OF THE APPOINTMENT OF DELOITTE & TOUCHE LLP AS INDEPENDENT AUDITORS (Page 46)

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CORPORATE GOVERNANCE PRINCIPLES
AND BOARD MATTERS

Our Board is committed to upholding the values of good corporate governance. In recognition of the relationship between corporate governance and long term performance, and as a result of our ongoing engagement with and feedback from our shareholders, theour Board has embarked on a review of the Company'scontinues to proactively evaluate our corporate governance principles. The Board expects that corporate governance reform will be a multi-year process and, as it weighs various alternatives, the Board is prioritizing its consideration based on a review of best practices and input from our shareholders. Based on these principles, the Board has established the following priorities and taken the following steps:last year our Board:

•

had meaningful engagements with manyamended our Declaration of Trust to declassify our Board so that all of our Trustees will stand for election annually beginning with our 2023 annual meeting of shareholders, a measure which was supported by more than 71% of our shareholders;



•

conducted a shareholder outreach to all of our shareholders who hold 1% or more of our common shares;



•

retained Korn Ferry, a leading executive search and consulting firm, to help identify and evaluatevet candidates to expand and refresh theour Board; and



•

adopted a proxy access bylaw (see page 9);enhanced our compensation and

sustainability disclosure and reporting in response to shareholder feedback.

•

amended

This year, our Bylaws so that, in a contested election, our Trustees are elected by a pluralityBoard continued to engage with Korn Ferry regarding board refreshment and expansion and conducted another shareholder outreach to all of the votes cast by our shareholders (see page 9).

The Board has also instituted a numberwho hold 1% or more of complementary mechanisms to allow shareholders to communicate their points of view, including:

•

the annual advisory vote to approve executive compensation (see page 22);



•

our commitment to thoughtfully consider shareholder proposals submitted to the Company;



•

the ability to attend and voice opinions at the annual meeting of shareholders; and



•

the ability to direct communications to individual Trustees or the entire Board (see page 10).

As theour Board continues on the path to enhanced good governance practices, we appreciate your support of theour Board and these initiatives.

We are currently governed by a fivesix member Board of Trustees. Trustees, including four Independent Trustees and two Managing Trustees, and our Board is currently divided into three classes. In 2020, with the support of more than 71% of our shareholders, our Board amended our Declaration of Trust to declassify our Board. Beginning with our 2021 Annual Meeting, the Trustees whose terms expire at an annual meeting will stand for election at the meeting for one-year terms and all Trustees will stand for election at the 2023 annual meeting of shareholders and, thereafter, for one-year terms.

Ensuring theour Board is comprised of Trustees who bring diverse viewpoints and perspectives, exhibit a variety of skills, professional experience and backgrounds and effectively represent the long-termlong term interests of shareholders is a top priority of theour Board and theour Nominating and Governance Committee. TheOur Board iscontinues to actively seeking to expandevaluate its composition. Our Board's expansion and refresh its composition for several reasons, including to increaserefreshment activities have increased the ratio of Independent Trustees to Managing Trustees, createcreated more skill mix and diversity ensureand ensured a smooth transition ifas Trustees retire from our Board. Our Nominating and when a Trustee decides to retire or otherwise leaves theGovernance Committee and our Board or does not receive a majority of shareholder votes cast, ensure that the Board is comprised of individualshave an ongoing engagement with a diverse set of backgrounds, perspectives and skills and allow the Board to retire members who fail to receive a requisite amount of shareholder support. The Board believes that continuity is important to the effective conduct of our business and expects the expansion and refreshment process will take place over several years. To facilitate these efforts, the Board has retained Korn Ferry, a leading executive search and consulting firm, to act as an advisor and to assist theour Nominating and Governance Committee in:

•

identifying and evaluating potential trustee candidates;



•

creating an even playing field among candidates identified regardless of source;



•

using the criteria, evaluations and references to prioritize candidates for consideration regardless of source; and



•

assisting in attracting and vetting candidates.

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THE BOARD BELIEVES THAT ITS MEMBERS SHOULD:

Our Nominating and Governance Committee screens and recommends candidates for nomination by our full Board. Our Nominating and Governance Committee is assisted with its recruitment efforts by its ongoing engagement with Korn Ferry, which recommends candidates that satisfy our Board's criteria. They also provide research and pertinent information regarding candidates, as requested.

We follow the Investor Stewardship Group's ("ISG") Corporate Governance Framework for U.S. Listed Companies, as summarized below:

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In addition, the Board has determined that the Board, as a whole, should strive to have the right mix of characteristics and skills necessary to effectively perform its oversight responsibilities. The Board believes that Trustees with one or more of the following professional skills or experiences can assist in meeting this goal:

The Nominating and Governance Committee and the Board consider the qualifications, characteristics and skills of Trustees and Trustee candidates individually and in the broader context of the Board's overall composition when evaluating potential nominees for election as Trustee. The Nominating and Governance Committee and the Board also expect to ask Korn Ferry to assist in considering the qualifications of, and evaluating, potential nominees.

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Overview. Our business strategy for our life science and medical office portfolio (our "office portfolio" incorporates a focus on sustainable approaches to operating these properties in a manner that benefits our shareholders, tenants and the communities in which we are located. We seek to operate those properties in ways that improve the economic performance of their operations, while simultaneously ensuring tenant comfort and safety, managing energy and water consumption, as well as greenhouse gas emissions.

Our strategy for our senior housing operated portfolio ("SHOP") is to work with our SHOP manager, Five Star Senior Living Inc. ("FVE"), to prioritize the safety and well being of our residents and FVE's team members, particularly during the COVID 19 pandemic, while also seeking to maximize the operating efficiencies of our senior living communities.

Our environmental, social and governance initiatives for our office portfolio are primarily implemented by our manager, RMR LLC, and for our SHOP portfolio, by FVE, and focus on a complementary set of objectives, including the following:

•

Responsible Investment: We seek to invest capital in our properties that both improves environmental performance and enhances asset value. During the acquisition of properties, RMR LLC assesses, among other things, environmental sustainability opportunities and climate related risks as part of the due diligence process.



•

Environmental Stewardship: We seek to improve the environmental footprint of our properties, including by reducing energy consumption and water usage, especially when doing so may reduce operating costs and enhance the properties' competitive position. As a result of these ongoing efforts RMR LLC has helped in generating the following portfolio-wide achievements for our office portfolio:



o

Certifying more than 1.5 million square feet across thirteen properties through the Environmental Protection Agency's ("EPA") ENERGY STAR® program, which nearly doubles the certified square feet and number of properties compared to 2019;



o

Benchmarking 3.6 million square feet across 38 properties, using the EPA's ENERGY STAR® portfolio manager tool; and



o

Owning 1.2 million square feet of Leadership in Energy and Environmental Design ("LEED") Gold certified properties, a certification program by the U.S. Green Building Council that recognizes performance in location and planning, sustainable site development, water savings, energy efficiency, materials selection, waste reduction, indoor environmental quality, innovative strategies and attention to priority regional issues.



•

Quality of the Resident Experience in our SHOP Portfolio:



o

FVE provides comprehensive resident programming, including Lifestyle 360™, its signature resident enrichment program, and Bridge to Rediscovery™, its award-winning memory care program designed to provide our memory care residents fulfilling lives and positive experiences at our communities.



o

FVE's culinary experience offers exceptional and creative chef crafted meals focusing on nutritional health and seasonal variety, and social engagement.



o

In response to the COVID-19 Pandemic FVE has enhanced the resident experience by:



§

Implementing new group activities that allow for engagement while maintaining social distancing.



§

Continuing to provide devices and connectivity options for interaction with family members, as well as virtual programming opportunities and distance learning.



§

Frequent COVID-19 testing provided to residents as necessary and free of charge.

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§

Vaccination clinics for both doses of the COVID-19 vaccine provided at substantially all our communities.



§

Complimentary counseling and support services for residents.



•

Investments in Human Capital: We rely on our managers to hire, train, and develop a workforce that meets the needs of our business, contributes positively to our society and helps reduce our impact on the natural environment.

RMR LLC

RMR LLC employs approximately 600 real estate professionals across the United States. In 2020, RMR LLC was recognized by The Boston Globe as a "Top Place to Work", by Fortune magazine as one of the "100 Fastest Growing Companies", by the EPA as an "ENERGY STAR Partner of the Year", by the Boston Business Journal as the "Fastest Growing Middle Market Company in Massachusetts," and it ranked 9th on Commercial Property Executive's Top Commercial Property Management Companies. Last year, RMR LLC also received the Real Estate Management Excellence Award for Employee & Leadership Development from the Institute of Real Estate Management.

RMR LLC's recruiting programs, on-boarding, retention programs and its development and training programs currently include the following:

o

Leadership Development Program: This two-year rotational program prepares newly hired graduates holding a Master of Business Administration degree for future leadership roles by providing an expansive view into all RMR LLC's client companies.



o

LiveWell Employee Wellness Program: RMR LLC's LiveWell program provides resources and incentives to enhance employees' physical, emotional and financial wellness.



o

Managing with Impact: RMR LLC utilizes Managing with Impact workshops for managers throughout the company to expand their perspectives and increase their confidence as a new manager. Within their first year, managers complete the workshop and learn how to effectively delegate, solve problems and give meaningful performance feedback.



o

Tuition Reimbursement Program: RMR LLC offers up to $20,000 in annual tuition assistance for work-related education from accredited colleges and universities in order to deepen employees' skillsets and support personal enrichment.



o

Engineering Development Program: Given the increasing challenges within the real estate industry of attracting qualified engineers, RMR LLC made it a strategic focus to develop the next generation of qualified building engineers. Over the last year, it launched a program to standardize the recruitment and development of engineering candidates to prepare them for open positions and to plan for future engineering needs. RMR LLC recruited from various trade schools and job fairs to identify candidates for the two-year program. The curriculum includes specific training in electrical, HVAC, or plumbing trades and covers a range of essential engineering staff development topics.



o

Industry Associations & Credentials: In order to further their professional development, many of RMR LLC's employees seek out credentials and association memberships, with any membership costs reimbursed by RMR LLC. Examples of credentials and association memberships include: Building Owners and Managers Association Membership and Event Participation, Certified Property Manager, Certified Public Accountant and National Association of Industrial and Office Properties.

FVE

FVE had approximately 19,000 team members, including approximately 12,000 full time and 7,000 part-time. FVE's team member engagement initiatives align with its goal of being an employer of choice with a thriving workforce that encourages career enrichment and positions it for growth.

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FVE's recruiting programs, on-boarding and retention programs and development and ongoing training programs currently include the following:

o

Team Member Engagement: Management reviews team member engagement and satisfaction surveys to monitor employee morale and receive feedback on a variety of issues.



o

Rewards: FVE rewards team members for innovation and productivity. It has several recognition programs for team members at various levels of the organization.



o

Tuition Reimbursement Program: FVE offers tuition assistance for work-related education from accredited colleges and universities in order to deepen team members' skill sets and support personal enrichment.

FVE also prioritizes ongoing education and training for all team members across the organization as follows:

o

Training and Development: FVE offers a robust learning management platform to provide training and development opportunities to all team members. In 2020, team members took an average of approximately 17 hours of training assignments per year. In addition, new hires are assigned 16 hours of general orientation training.



o

Industry Associations & Credentials: In order to further their professional development, many of FVE's team members seek out credentials or hold professional licenses and association memberships. Examples of credentials, professional licenses and association memberships include: Medical Licenses, Licensed Practical Nurses, Registered Nurses, Certified Medical Assistants, Certified Physical and Occupational Therapists, Speech-Language Pathologists, Certified Fitness Trainers, Cardiopulmonary resuscitation certifications (CPR), First Aid Certifications, Law Licenses and Certified Public Accountant accreditations.



•

Corporate Citizenship: We seek to be a responsible corporate citizen and to strengthen the communities in which we own properties. Our managers regularly encourage their employees to engage in a variety of charitable and community programs, including participation in a company-wide service day and a charitable giving matching program.



•

Diversity & Inclusion: We value a diversity of backgrounds, experience and perspectives. Our Board is comprised of 33.3% women and 16.7% members of underrepresented communities. Our managers are equal opportunity employers with all qualified applicants receiving consideration for employment without regard to race, color, religion, sex, sexual orientation, gender identity, national origin, disability or protected veteran status. Our managers are committed to racial equality and fostering a culture of diversity and inclusion. As of September 30, 2020, 34% and 27% of RMR LLC's employees were female and members of underrepresented communities, respectively. As of December 31, 2020, approximately 77% and 42% of FVE's approximately 19,500 team members were female and members of underrepresented communities, respectively.

To learn more about RMR LLC's and our sustainability initiatives, visit www.rmrgroup.com/corporate-sustainability.

Sustainability Accounting Metrics. The following disclosures are informed by the guidance of the Sustainability Accounting Standards Board ("SASB") Standards for Real Estate. To the extent an accounting metric, as defined by the SASB Standard, is not applicable to our portfolio or data to report on the applicable accounting metric is not available to us, we have not made any disclosure.

For the following SASB disclosures, the information presented is as of December 31, 2020 and relates to our office portfolio, inclusive of life science ("Life Science") and medical office buildings ("MOB"), and those Same Property senior housing communities that we own and which are operated by FVE. "Same Property" information includes properties owned continuously since January 1, 2019. Where applicable, the information presents DHC properties on consolidated basis, including two life science properties containing 1.1 million square feet that is owned in a joint venture arrangement in which DHC owns a 55% equity interest.

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In 2020, the COVID-19 pandemic, along with local, state and Federal social distancing recommendations, created an environment of reduced building utilization. This lower property utilization is evident in the presented sustainability metrics below. It is our expectation that, in a post-pandemic environment as businesses return to normal and our property utilization improves, the energy and water consumption of our properties will increase above 2020 levels.

I.

Energy management integration discussion (SASB Accounting Metric Code: IF-RE-130a.5):

RMR LLC deploys on our behalf energy management best practices at our office portfolio, which include:

•

Centralized utility bill processing and payment system;

•

ENERGY STAR® benchmarking;

•

Real-time energy monitoring;

•

Daytime and nighttime energy audits;

•

Light Emitting Diodes (LED) lighting upgrades;

•

Annual energy engagement competitions;

•

Energy performance training for property operations teams;

•

Energy performance review for end-of-life heating, ventilation and air conditioning (HVAC) equipment replacements; and

•

Capital deployment dedicated to generating returns on energy efficiency upgrades.

As a result of these energy management efforts, we have reduced energy and water usage helping to generate both economic and environmental benefits.

II.

Sections II, III and IV below provide SASB-aligned energy-related metrics. Energy consumption data coverage in square feet and as a percentage of Same Property floor area (SASB Accounting Metric Code: IF-RE-130a.1):

The following illustrates Same Property energy data available as compared to the total population of Same Property assets.

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III.

Total energy consumption and change in energy consumption for covered Same Property area (SASB Accounting Metric Codes: IF-RE-130a.2 and IF-RE-130a.3):

IV.

Percentage of eligible portfolio that (i) has obtained an energy rating and (ii) is certified to ENERGY STAR® (SASB Accounting Metric Code: IF-RE-130a.4):

Medical office and life science properties are not currently eligible to earn certification through the EPA's ENERGY STAR® program. However, we have thirteen properties with operating characteristics similar to traditional office properties, which makes them eligible for certification. All of these eligible properties are certified.

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V.

Water management integration discussion (SASB Accounting Metric Code: IF-RE-140a.4):

On our behalf, RMR LLC supports water management practices at our office portfolio that reduce operating costs as well as our impact on the consumption of natural resources. Water usage is managed by benchmarking water performance to establish a baseline and to measure performance improvements resulting from conservation measures. Benchmarking is performed through the EPA's ENERGY STAR® Portfolio Manager online platform.

Some cities and states in which we own properties require annual whole-building energy and water use disclosure. In these jurisdictions, RMR LLC engages with tenants to collect and report any direct tenant-paid energy and water consumption for our office portfolio.

RMR LLC also routinely implements water efficiency and water use reduction projects at our office portfolio, which include upgrades to indoor plumbing fixtures, low-flow water closets and urinals, low-flow flush valves, low-flow automatic faucet controls, low-flow faucet aerators and shower heads, water-efficient landscaping and cooling tower water management.

Sections VI and VII below provide SASB-aligned water-related metrics.

VI.

Water withdrawal data coverage in square feet and as a percentage of Same Property floor area and percentage in regions with High or Extremely High Baseline Water Stress (SASB Accounting Metric Codes: IF-RE-140a.1):

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Baseline Water Stress measures total annual water withdrawals (municipal, industrial, and agricultural) expressed as a percent of the total annual available flow. Higher values indicate more users are competing for limited water supplies.

VII.

Total water withdrawn and percent change for Same Property area with data coverage (SASB Accounting Metric Codes: IF-RE-140a.2 and IF-RE-140a.3):

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VIII.

Description of approach to measuring, incentivizing, and improving sustainability impacts of tenants (SASB Accounting Metric Code: IF-RE-410a.3):

On our behalf, RMR LLC seeks to provide best-in-class property operations and healthy, efficient environments for our tenants and encourage continual engagement that promotes long-lasting relationships and sustainable behaviors.

RMR LLC has internal policies that govern environmentally responsible property operations. We also utilize green lease language, where possible, to promote mutual commitment to environmentally friendly practices and operational efficiencies with our tenants.

RMR LLC prioritizes LEED certification and recertification projects by reviewing a variety of sustainability and leasing criteria such as high ENERGY STAR® scores and access to public transportation and near-by amenities. We believe that taking the initiative to submit for and attain LEED certification adds value to our properties and enhances tenant satisfaction, which reflects our commitment to environmental sustainability.

IX.

Area of properties located in FEMA Special Flood Hazard Areas or foreign equivalent, by property subsector (SASB Accounting Metric Code: IF-RE-450a.1):

X.

Description of climate change risk exposure analysis, degree of systematic portfolio exposure, and strategies for mitigating risks (SASB Accounting Metric Code: IF-RE-450a.2):

We define climate change resilience as our ability to anticipate, prepare for and recover from adverse physical climate activity such as increased severity of acute weather events and chronic changes to weather patterns as well as identify and plan for climate-related transitional activities such as changes in policy and market-driven expectations.

In preparation for and in response to property-level natural hazards, our manager, RMR LLC, utilizes dynamic geographic mapping tools which allows them to quickly assess the risk to our office portfolio from the rapidly changing natural hazards related to coastal and river flooding.

In advance of a natural hazard event, RMR LLC directs resources to our office portfolio identified as potentially impacted through these mapping tools. The resources made available include access to senior management and mobilization of equipment and personnel. Rapid response personnel may also be directed to properties after a weather event has occurred.

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Properties susceptible to inundation from flood waters are evaluated routinely. The evaluation may include implementing tenant and local agency coordination protocols, property incident response plan reviews, insurance provider assessments and the implementation of physical protection elements, such as flood protection barriers.

We routinely utilize technology to evaluate our properties for energy and water performance. Such activities support lower operating expenses, improve comfort for our tenants and reduce our exposure to impacts from policies targeting greenhouse gas emissions.

Our portfolio strategy includes the development of hazard and vulnerability assessments of our existing properties and scenario planning and economic risk reviews of property development opportunities over long- term ownership periods.

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TheOur Board is elected by our shareholders to oversee the Company'sour business and long term strategy. As part of fulfilling its responsibilities, theour Board oversees the safeguarding of the Company'sour assets, the maintenance of appropriate financial and other internal controls and the Company'sour compliance with applicable laws and regulations. Inherent in these responsibilities is theour Board's understanding and oversight of the various risks the Company faces. Thewe face. Our Board considers that risks should not be viewed in isolation and should be considered in virtually every business decision and as part of the Company'sour business strategy.

TheOur Board oversees risk as part of its general oversight of theour Company. Oversight of risk is addressed as part of various Board and Board committee activities and through regular and special Board and Board committee meetings. TheOur day to day business of the Company is conducted by our manager, The RMR Group LLC, ("RMR LLC"), and RMR LLC and the Company'sour officers and Director of Internal Audit are responsible for incorporating risk management in their activities. The Company'sOur Director of Internal Audit reports to theour Audit Committee and provides the Companyus with advice and assistance with the Company'sour risk management function.

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In discharging their oversight responsibilities, theour Board and Board committees review regularly a wide range of reports provided by RMR LLC and other service providers, provide, including:

•

reports on market and industry conditions;



•

reports on the impact of the COVID-19 pandemic on our business;



•

operating and regulatory compliance reports;



•

financial reports;



•

reports on risk management activities;and our Environmental, Social and Governance activities and initiatives;



•

regulatory and legislative updates that may impact the Company;us;



•

reports on the security of the Company'sour information technology processes and the Company'sour data; and



•

legal proceedings updates and reports on other business related matters.

TheOur Board and Board committees discuss these matters among themselves and with representatives of RMR LLC, our officers, of the Company, theour Director of Internal Audit, legal counsel, the Company'sour independent auditors and other professionals, as appropriate.

TheOur Audit Committee takes a leading role in helping theour Board fulfill its responsibilities for oversight of the Company'sour financial reporting, internal audit function, risk management, including cybersecurity, and the Company'sour compliance with legal and regulatory requirements. TheOur Board and Audit Committee review periodic reports from the Company'sour independent auditors regarding potential risks, including risks related to the Company'sour internal control over financial reporting. TheOur Audit Committee also reviews, approves and oversees an internal audit plan developed by the Company'sour Director of Internal Audit with the goal of helping the Companyus systematically evaluate the effectiveness of itsour risk management, control and governance processes on an annual basis. The Audit Committee considers risks relating to cybersecurity, receiving regular reports from management regarding cybersecurity risks and countermeasures being undertaken or considered by the Company, including updates on the internal and external cybersecurity landscape and relevant technical developments. TheOur Audit Committee meets at least quarterly and reports its findings to theour Board. TheOur Audit Committee also meets periodically with the Company'sour Director of Internal Audit to review the results of the Company'sour internal audits, and directs or recommends to theour Board actions or changes it determines appropriate to enhance or improve the effectiveness of the Company'sour risk management.

TheOur Audit Committee considers risks related to cybersecurity and receives regular reports from our management regarding cybersecurity risks and countermeasures being undertaken or considered by us, including updates on the internal and external cybersecurity landscape and relevant technical developments.

Our Compensation Committee whose duties are detailed in its charter, among other duties, evaluates the performance of the Company'sour Director of Internal Audit and RMR LLC's performance under the Company'sour business and property management agreements, including any perceived risks created by compensation arrangements. Also, theour Compensation Committee and theour Board consider that the

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Company haswe have a share award program that requires share awards to executive officers to vest over a period of years. The Company believesWe believe that the use of share awards vesting over time rather than stock options mitigates the incentives for the Company'sour management to undertake undue risks and encourages management to make longerlong term and appropriately risk balanced decisions.

It is not possible to identify all of the risks that may affect the Companyus or to develop processes and controls to eliminate all risks and their possible effects, and processes and controls employed to address risks may be limited in their effectiveness. Moreover, it is necessary for the Companyus to bear certain risks to achieve itsour objectives. As a result of the foregoing and other factors, the Company'sour ability to manage risk is subject to substantial limitations.

To learn more about the risks facing the Company,we face, you can review the matters discussed in Part I, "Item 1A. Risk Factors" and "Warning Concerning Forward LookingForward-Looking Statements" in our Annual Report to Shareholders for the fiscal year ended December 31, 2018 ("Annual2020 (the "Annual Report"). The risks described in the Annual Report are not the only risks facing the Company.we face. Additional risks and uncertainties not currently known or that may currently be deemed to be immaterial also may materially adversely affect the Company'sour business, financial condition or results of operations in future periods.

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Under the corporate governance listing standards of the Nasdaq theand our governing documents, our Board must consist of a majority of Independent Trustees. Our governing documents also require that a majority of the Board be Independent Trustees. Under our governing documents, Independent Trustees are Trustees who are not employees of RMR LLC, are not involved in the Company'sour day to day activities and who meet the qualifications for independence under the applicable rules of the Nasdaq and the SEC.Securities and Exchange Commission (the "SEC").

TheOur Board affirmatively determines whether Trustees have a direct or indirect material relationship with the Company,us, including the Company'sour subsidiaries, other than serving as the Company'sour Trustees or trustees or directors of the Company'sour subsidiaries. In making independence determinations, theour Board observes the Nasdaq and SEC criteria, as well as the criteria set forth in our governing documents. When assessing a Trustee's relationship with the Company, theus, our Board considers all relevant facts and circumstances, not merely from the Trustee's standpoint, but also from that of the persons or organizations with which the Trustee has an affiliation. Based on this review, theour Board has determined that John L. Harrington, Lisa Harris Jones, Daniel F. LePage and Jeffrey P. Somers currently qualify as independent trustees under applicable Nasdaq and SEC criteria and as Independent Trustees under our governing documents. In making these independence determinations, theour Board reviewed and discussed additional information provided by the Trusteesus and the CompanyTrustees with regard to each of the Trustees' relationships with the Company, us, RMR LLC or The RMR Group Inc. ("RMR Inc. or"), the managing member of RMR LLC, and the other companies to which RMR LLC or its subsidiaries provide management services. TheOur Board has concluded that none of these threefour Trustees possessed or currently possesses any relationship that could impair his, her or hertheir judgment in connection with his, her or hertheir duties and responsibilities as a Trustee or that could otherwise be a direct or indirect material relationship under applicable Nasdaq and SEC standards.

Pursuant to the Company'sour Governance Guidelines, our Independent Trustees are expected to meet at least twice per year in regularly scheduled meetings at which only Independent Trustees are present. Our Independent Trustees also meet separately with the Company'sour officers, with the Company'sour Director of Internal Audit and with the Company'sour independent auditors. The presiding Trustee for purposes of leading Independent Trustee sessions will be the Lead Independent Trustee, unless the Independent Trustees determine otherwise.

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In accordance with our governing documents, the Board is comprised of five Trustees, including three Independent Trustees and two Managing Trustees, and our Board is divided into three classes, with each Trustee of each class elected at an annual meeting of shareholders serving for a term that continues until the third annual meeting of shareholders following his or her election and until his or her successor is elected and qualifies. All Trustees play an active role in overseeing the Company'sour business both at theour Board and committee levels. As set forth in the Company'sour Governance Guidelines, the core responsibility of our Trustees is to exercise sound, informed and independent business judgment in overseeing theour Company and itsour strategic direction. Our Trustees are skilled and experienced leaders and currently serve or have served as members of senior management in public and private for profit organizations and law firms, and have also served in academia. Our Trustees may be called upon to provide solutions to various complex issues and are expected to, and do, ask hard questions of the Company'sour officers and advisers. TheOur Board is small, which facilitates informal discussions and communication from management to theour Board and among Trustees.

ThreeAdam D. Portnoy serves as Chair of our Board. Our Board believes that Mr. Portnoy's leadership of RMR LLC and extensive familiarity with our day to day business provide valuable insight for our Board.

Four of our Trustees, including one of our Trustee nominees for election at the 2019our 2021 Annual Meeting, are independent under the applicable Nasdaq and SEC criteria and our governing documents. All of the members of theour Audit Committee, Nominating and Governance Committee and Compensation Committee are independent under the applicable listing requirements and rules of the Nasdaq and other applicable laws, rules and regulations, including those of the SEC. As set forth in our governing documents, two of our Trustees are Managing Trustees, persons who have been employees, officers or directors of RMR LLC or who have been involved in the Company'sour day to day activities for at least one year prior to his, her or hertheir election as Trustees.

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We have a Lead Independent Trustee who is selected annually by the vote of a majority of our Independent Trustees. We do not have a Chairman of the Board. Currently, Ms. Harris Jones serves as our Lead Independent Trustee. Our Lead Independent Trustee has well-defined, substantive responsibilities that include, among others that may be assigned from time to time:include:

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presiding at all meetings of theour Board at which the Chair or a Managing Trustees areTrustee is not present, includingpresent;



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presiding at all meetings and executive sessions of the Independent Trustees;



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serving as liaison between the Independent Trustees and the senior management team;



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having the authority to call meetings of the Independent Trustees or executive sessions of the Board;Independent Trustees;



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serving as the principal liaison between the Independent Trustees and the senior management team;



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arranging, together with the Chair of our Board, for appropriate information (including quality and quantity) to be timely provided to our Board and the Independent Trustees;



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assisting theour Compensation Committee in its annual evaluation of the performance of the Company's management;our management and of our manager, RMR LLC;



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placing and reviewing items onassisting with setting Board meeting agendas;agendas and arranging meeting schedules, including to ensure that there is sufficient time for discussion of all agenda items;



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considering suggestions for meeting agenda items byfrom other Independent Trustees.Trustees;



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authorizing the retention of advisors and consultants who report directly to the Independent Trustees when appropriate; and



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if requested, and in coordination with the Chair of our Board and our management, being reasonably available for consultation and direct communication with shareholders.

TheOur Board is committed to corporate governance that promotes the long term interests of our shareholders. TheOur Board has established Governance Guidelines that provide a framework for effective governance. TheOur Board regularly reviews developments in corporate governance and updates our Governance Guidelines and other governance materials as it deems necessary and appropriate.

The Company hasWe have also adopted a Code of Business Conduct and Ethics (the "Code") to, among other things, provide guidance to our Trustees and RMR LLC's (and its subsidiaries') board members, officers and in the case of RMR LLC, its officers and employees, and its parent's and subsidiaries' directors, officers and employees to ensure compliance with applicable laws and regulations.

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TheOur Board has an Audit Committee, Compensation Committee and Nominating and Governance Committee. TheOur Audit Committee, Compensation Committee and Nominating and Governance Committee each have adopted a written charter, and each Board committee reviews its written charter on an annual basis to consider whether any changes are required.

Our corporate governance materials are available for review in the governance section of our website, including our Governance Guidelines, the charter for each Board committee, the Code, and information about how to report concerns or complaints about accounting, internal accounting controls or auditing matters and any violations or possible violations of the Code, and how to communicate with our Trustees, individually or as a group.Trustees. To access these documents on the Company'sour website visitwww.snhreit.comwww.dhcreit.com.

In April 2019, the Board adopted an amendment to our Bylaws to provide that, in contested elections, our Trustees will be elected by a plurality of the votes cast by our shareholders. This amendment was adopted to ensure that, in contested elections, those Trustee nominees who receive the largest number of votes are elected by shareholders to the Board. This amendment aligns our voting practices for contested elections with the guidelines of many institutional shareholders and proxy advisory firms and is consistent with best practices.

Our governing documentsGovernance Guidelines provide that if an incumbent Trustee does not receive a majority of the votes cast in an uncontested election, the Trustee will submit an offer to resign from theour Board. In such circumstance, theour Nominating and Governance Committee will make a recommendation to theour Board on whether to accept or reject the resignation offer, or whether other action should be taken. TheOur Board will

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act on the resignation offer taking into account the recommendation of theour Nominating and Governance Committee and make its decision within 90 days following the certification of the election results.

In April 2019, after extensive analysisOur Insider Trading Policies and shareholder engagement, the NominatingProcedures expressly prohibit members of our Board and Governance Committee recommended,our officers from engaging in hedging transactions involving our securities and the Board adopted, a proxy access bylaw pursuantthose of RMR Inc. or any other public company to which a shareholder,RMR LLC or a group of up to 20 shareholders, owning at least three percent of the outstanding Common Shares continuously for at least three years, may nominate and include in the Company's proxy materials for an annual meeting Trustee nominees constituting up to the greater of two nominees or 20% of the number of Trustees on the Board that holders of our Common Shares are entitled to elect, provided that for so long as the Company has a classified Board of less than nine Trustees, such number of Trustee nominees will be reduced so that for any annual meeting it does not exceed one-half of the number of Trustees to be elected at the meeting as noticed by the Company rounded down to the nearest whole number (but not rounded down as a result of this proviso to less than one). Shareholders making such a nomination and their nominees must also satisfy the informational, documentation and other requirements specified by Section 2.18 of our Bylaws.its affiliates provide management services.

The Nominating and Governance Committee is responsible for identifying and evaluating nominees for Trustee and for recommending to the Board nominees for election at each annual meeting of shareholders. The Nominating and Governance Committee may consider candidates suggested by the Company's Trustees, officers or shareholders or by others. Shareholders who would like to recommend a Trustee nominee for the position of Trustee should submit their recommendations in writing by mail to the Chair of theour Nominating and Governance Committee, c/o Senior Housing PropertiesDiversified Healthcare Trust, Secretary, at Two Newton Place, 255 Washington Street, Suite 300, Newton, Massachusetts 02458 or by email to secretary@snhreit.com.secretary@dhcreit.com. Any such recommendation shallshould include a description of the candidate's qualifications for Board service, the candidate's written consent to be considered for nomination and to serve if nominated and elected, as well as the addresses and telephone numbers for contacting the shareholder and the candidate for more information. TheOur Nominating and Governance Committee may

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request additional information about the shareholder recommended nominee or about the shareholder recommending the nominee. Recommendations by shareholders will be considered by theour Nominating and Governance Committee in its discretion using the same criteria as other candidates it considers.

As noted above, aA shareholder, or a group of up to 20 shareholders, owning at least three percent of the outstanding Common Shares continuously for at least three years may utilize our proxy access bylaw to nominate and include in the Company'sour proxy materials Trustee candidate(s) for election at an annual meeting of shareholders provided that the shareholder(s) and the nominee(s) satisfy the informational, documentation and other requirements specified by Section 2.18 of our Bylaws.

Shareholders seeking to nominate one or more individuals as a Trustee candidate without relying on our proxy access bylaw shallmust comply with the advance notice requirements for shareholder nominations set forth in Section 2.14 of our Bylaws, which include, among other things, requirements as to the proposing shareholder's timely delivery of advance notice, continuous requisite ownership of Common Shares and submission of specified documentation and information.

TheOur Board has established a process to facilitate communication by shareholders and other interested partiesstakeholders with our Trustees. Communications should be addressed to Trustees in care of the Secretary, Senior Housing PropertiesDiversified Healthcare Trust, Two Newton Place, 255 Washington Street, Suite 300, Newton, Massachusetts 02458 or by email to secretary@snhreit.com.secretary@dhcreit.com.

Our business strategy incorporates and values environmental sustainability principles. We seek to operate our properties in a manner that improves the environmental efficiency of their operations. We regularly consider ways to improve our internal culture and the communities in which we operate. Our environmental sustainability and community engagement strategies are primarily implemented by our manager, RMR LLC, and focus on a complementary set of objectives, including the following:

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Responsible Investment:During the acquisition of properties, RMR LLC assesses, among other things, environmental sustainability opportunities and climate related risks as part of the due diligence process. We regularly seek to invest in sustainability practices that improve environmental performance and enhance asset value.



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Environmental Stewardship:We seek to improve the environmental footprint of our properties, including by reducing energy consumption and water usage at our properties, especially when doing so may reduce operating costs and improve the properties' competitive positions.



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Corporate Citizenship:We seek to be a responsible corporate citizen and to strengthen the communities in which we own properties. We have no employees but our manager, RMR LLC, regularly encourages its employees to engage in a variety of charitable and community programs, including participation in a company-wide service day and a matching charitable giving program.



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Diversity:We value a diversity of backgrounds, experience and perspectives. Our Board is comprised of 40% women and in 2018 we were recognized by 2020 Women on Boards. RMR LLC is an equal opportunity employer.

To learn more about the Company's and RMR LLC's sustainability initiatives, visitwww.rmrgroup.com/corporate-sustainability.

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Deadline to Submit Proposals pursuant to Rule 14a-8 for the 20202022 Annual Meeting of Shareholders:Shareholders: Shareholder proposals pursuant to Rule 14a-8 under the Securities Exchange Act of 1934, as amended (the "Exchange Act"), must be received at our principal executive officesoffice on or before December 7, 2019November 30, 2021 in order to be eligible to be included in the proxy statement for the 20202022 annual meeting of shareholders; provided, that, if the date of the 20202022 annual meeting of shareholders is more than 30 days before or after May 21, 2020,June 3, 2022, such a proposal must be submitted within a reasonable time before we begin to print itsour proxy materials. Under Rule 14a-8, the Company iswe are not required to include shareholder proposals in itsour proxy materials in certain circumstances or if conditions specified in the rule are not met.

Deadline to Submit Trustee Proxy Access Nominations for the 20202022 Annual Meeting of Shareholders:Shareholders: Under our proxy access bylaw, a shareholder or a group of up to 20 shareholders owning at least three

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percent of the Company'sour outstanding Common Shares continuously for at least three years may nominate and include in the Company'sour proxy materials for the 20202022 annual meeting of shareholders Trustee nominees constituting up to the greater of two nominees or 20% of the number of Trustees on theour Board that holders of the Company'sour Common Shares are entitled to elect,elect; provided that, ifas we have a classifieddeclassify our Board, of less than nine Trustees, such number of Trustee nominees will be reduced so that for the 20202022 annual meeting of shareholders it does not exceed one-half of the number of Trustees to be elected at the 20202022 annual meeting of shareholders as noticed by the Companyus (so long as our Board consists of less than nine Trustees) rounded down to the nearest whole number (but not rounded down as a result of this proviso to less than one); provided further that. In addition, the shareholder(s) and nominee(s) must satisfy the informational, documentation and other requirements specified by Section 2.18 of our Bylaws. Notice of a proxy access nomination for consideration at our 20202022 annual meeting of shareholders must be received at the Company'sour principal executive officesoffice not later than 5:00 p.m., Eastern time, on December 7, 2019November 30, 2021 and not earlier than November 7, 2019.October 31, 2021.

Deadline to Submit Other Nominations and Proposals for the 20202022 Annual Meeting of Shareholders under our Bylaws:Bylaws: To be timely, shareholder nominations and proposals intended to be made outside of Rule 14a-8 under the Exchange Act and outside of the proxy access bylaw at the 20202022 annual meeting of shareholders must be received by our Secretary at our principal executive offices,office, in accordance with the requirements of our Declaration of Trust and Bylaws, not later than 5:00 p.m., Eastern time, on December 7, 2019November 30, 2021 and not earlier than November 7, 2019;October 31, 2021; provided, that, if the date of the 20202022 annual meeting of shareholders is more than 30 days earlier or later than May 21, 2020,June 3, 2022, then a shareholder's notice must be so delivered not later than 5:00 p.m., Eastern time, on the tenth day following the earlier of the day on which (i) notice of the date of the 20202022 annual meeting of shareholders is mailed or otherwise made available or (ii) public announcement of the date of the 20202022 annual meeting of shareholders is first made by the Company.us. Shareholders making such a nomination or proposal must comply with the advance notice and other requirements set forth in our Declaration of Trust and Bylaws, which include, among other things, requirements as to the shareholder's timely delivery of advance notice, continuous requisite ownership of Common Shares, holding of a share certificate for such shares at the time of the advance notice and submission of specified information.

The foregoing description of the deadlines and other requirements for a shareholdershareholders to submit a proxy access or other nomination for election to theour Board or a proposal of other business for consideration at an annual meeting of shareholders is only a summary and is not a complete listing of all requirements. Copies of our Declaration of Trust and Bylaws, including the requirements for proxy access or other shareholder nominations and other shareholder proposals, may be obtained by writing to the Company'sour Secretary at Senior Housing PropertiesDiversified Healthcare Trust, Two Newton Place, 255 Washington Street, Suite 300, Newton, Massachusetts 02458, or from the SEC's website,www.sec.gov. Any shareholder considering making a proxy access or other nomination or other shareholder proposal should carefully review and comply with those provisions.

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PROPOSAL 1: ELECTION OF TRUSTEES

Upon the recommendation of theour Nominating and Governance Committee, theour Board has nominated John L. Harrington for electionLisa Harris Jones as an Independent Trustee in Class II and Adam D. PortnoyJennifer F. Francis as a Managing Trustee. Ms. Harris Jones currently serves on our Board, and Ms. Francis currently serves as our President and Chief Operating Officer. On February 24, 2021, Ms. Clark notified our Board of her decision to not seek re-election as a Managing Trustee upon the expiration of her current term. Ms. Clark's decision to not seek re-election to our Board was not due to any disagreement with us relating to our operations, policies or practices. Our Nominating and Governance Committee and our Board voted to nominate Ms. Francis for election as a Managing Trustee in Class II. Messrs. Harrington and Portnoy currently serve onto fill the Board. vacancy created by Ms. Clark's decision not to seek re-election.

If elected, Messrs. Harrington and Portnoyeach nominee would serve until the Company'sour 2022 annual meeting of shareholders and until hisher successor is duly elected and qualifies, subject to the individual'sher earlier death, resignation, retirement, disqualification or removal.

We expect that each nominee for election as a Trustee will be able to serve if elected. However, if a nominee should become unable or unwilling to serve, proxies may be voted for the election of a substitute nominee designated by theour Board.

AssumingBoard of Trustees' Qualifications and Experience

Our Trustees have a quorumgreat diversity of experience and bring to our Board a wide variety of skills, qualifications, viewpoints and backgrounds that strengthen their ability to carry out their oversight role on behalf of our shareholders.

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Snapshot of 2021 Board Nominees

Presented below is present ata snapshot of the meeting,expected composition of our Board immediately following our 2021 Annual Meeting, assuming the election of Jennifer F. Francis and Lisa Harris Jones and the expiration of Jennifer B. Clark's term as a Trustee. Our Board of Trustees believes that, collectively, our Trustees exhibit an effective mix of qualifications, experience and diversity.

A plurality of all the votes cast is required to elect a Trustee at the 2019our 2021 Annual Meeting.

The names, principal occupations and certain other information andregarding the Trustee nominees for Trustees, as well as a summary of the key experiences, qualifications, attributes and skills that led theour Nominating and Governance Committee and theour Board to conclude that such persons are currently qualified to serve as Trustees are set forth on the following pages.

TheOur Board of Trustees recommends a vote "FOR" the election of both Trustee nominees.

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