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

SCHEDULE 14A

Proxy Statement Pursuant to Section 14(a) of
the Securities Exchange Act of 1934 (Amendment No.          )

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TESARO, Inc.
1000 Winter Street
Waltham, Massachusetts 02451

NOTICE OF ANNUAL MEETING OF STOCKHOLDERS

        The 2018 Annual Meeting of Stockholders will be held on Thursday, May 10, 2018, at 8:30 a.m. local time, at The Conference Center at Waltham Woods, 860 Winter Street, Waltham, MA 02451 for the following purposes:

1.

to elect ten members of the board of directors from the nominees named in the accompanying proxy statement;



2.

to approve the TESARO, Inc., Non-Employee Director Compensation Policy, including compensation amounts for 2018;



3.

to approve, by non-binding vote, the Company's executive compensation;



4.

to approve an amendment to the TESARO, Inc., 2012 Employee Stock Purchase Plan to, among other things, increase the number of shares available for issuance thereunder by 275,000 shares;



5.

to ratify the appointment of Ernst & Young, LLP as the Company's independent registered public accounting firm for the fiscal year ending December 31, 2018; and



6.

to consider any other matters that properly come before the Annual Meeting or any adjournment or postponement thereof.

        Each outstanding share of TESARO, Inc. common stock (NASDAQ: TSRO) entitles the holder of record at the close of business on March 13, 2018, to receive notice of and to vote at the Annual Meeting or any adjournment or postponement of the Annual Meeting.

        WHETHER OR NOT YOU EXPECT TO ATTEND THE MEETING, WE URGE YOU TO VOTE YOUR SHARES BY INTERNET, TELEPHONE, OR BY SIGNING, DATING AND RETURNING THE PROXY CARD. IF YOU CHOOSE TO ATTEND THE ANNUAL MEETING, YOU MAY STILL VOTE YOUR SHARES IN PERSON, EVEN THOUGH YOU HAVE PREVIOUSLY VOTED OR RETURNED YOUR PROXY BY ANY OF THE METHODS DESCRIBED IN OUR PROXY STATEMENT. IF YOUR SHARES ARE HELD IN A BANK OR BROKERAGE ACCOUNT, PLEASE REFER TO THE MATERIALS PROVIDED BY YOUR BANK OR BROKER FOR VOTING INSTRUCTIONS.

        ALL STOCKHOLDERS ARE EXTENDED A CORDIAL INVITATION TO ATTEND THE MEETING.

		By Order of the Board of Directors
		Leon O. Moulder, Jr. Chief Executive Officer April 6, 2018

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TESARO, Inc.
1000 Winter Street
Waltham, Massachusetts 02451
PROXY STATEMENT FOR ANNUAL MEETING OF STOCKHOLDERS
To Be Held On Thursday, May 10, 2018

        This Proxy Statement (the "Proxy Statement") and the accompanying proxy are furnished to the stockholders of TESARO, Inc. (hereinafter, "we," "us," "TESARO" and the "Company") in connection with the solicitation of proxies by the TESARO board of directors, to be voted at the Annual Meeting of Stockholders (the "Annual Meeting") and at any adjournment or postponement of the Annual Meeting, which will be held at 8:30 a.m. local time on Thursday, May 10, 2018, at The Conference Center at Waltham Woods, 860 Winter Street, Waltham, MA 02451, for the purposes set forth in the accompanying Notice of Annual Meeting of Stockholders. The board of directors mailed this Proxy Statement and accompanying materials to each of the Company's stockholders entitled to vote at the Annual Meeting on or about April 6, 2018.

Important Notice Regarding the Internet Availability of Proxy Materials for the Stockholder Meeting to Be Held on Thursday, May 10, 2018.

        Our Annual Report to Stockholders and this Proxy Statement are also available electronically on the Internet at http://www.proxyvote.com.

ABOUT THE ANNUAL MEETING

Purpose of the Annual Meeting

        The purpose of the Annual Meeting is for our stockholders to consider and act upon the proposals described in this Proxy Statement and any other matters that properly come before the Annual Meeting or any adjournment or postponement thereof. In addition, management will report on TESARO's performance and respond to questions from stockholders. Management is presently aware of no other business to come before the Annual Meeting.

Proposals to be Voted Upon at the Annual Meeting

        At the Annual Meeting, our stockholders will be asked to consider and vote upon the following five proposals:

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Proposal No. 1: To elect ten members of the board of directors, each of whom will hold office until the next annual meeting of stockholders and until his or her successor is elected and qualified or until his or her earlier death, resignation or removal.



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Proposal No. 2: To approve the TESARO, Inc., Non-Employee Director Compensation Policy, including compensation amounts for 2018.



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Proposal No. 3: To approve, by non-binding vote, the Company's executive compensation.



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Proposal No. 4: To approve an amendment to the TESARO, Inc., 2012 Employee Stock Purchase Plan to, among other things, increase the number of shares available for issuance thereunder by 275,000 shares.

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Proposal No. 5: To ratify the appointment of Ernst & Young, LLP ("Ernst & Young") as the Company's independent registered public accounting firm for the fiscal year ending December 31, 2018.

        In addition, any other matters that properly come before the Annual Meeting or any adjournment or postponement thereof will be considered. Management is presently aware of no other business to come before the Annual Meeting.

Recommendation of the Board of Directors

        The board of directors recommends that you vote FOR each of the nominees to the board (Proposal 1), FOR approval of the TESARO, Inc., Non-Employee Director Compensation Policy, including compensation amounts for 2018 (Proposal 2), FOR approval, on a non-binding basis, of the Company's executive compensation (Proposal 3), FOR approval to an amendment to the TESARO, Inc., 2012 Employee Stock Purchase Plan to, among other things, increase the number of shares available for issuance thereunder by 275,000 shares (Proposal 4), and FOR the ratification of the appointment of Ernst & Young as our independent registered public accounting firm for the fiscal year ending December 31, 2018 (Proposal 5).

Voting at the Annual Meeting

        Stockholders will be entitled to vote at the Annual Meeting on the basis of each share held of record at the close of business on March 13, 2018 (the "Record Date").

        If on the Record Date you held shares of our common stock that are registered directly in your name with our transfer agent, Computershare Trust Company, N.A. ("Computershare"), you are considered the stockholder of record with respect to those shares, and Computershare is sending these proxy materials directly to you on our behalf. As a stockholder of record, you may vote in person at the Annual Meeting or by proxy. Whether or not you plan to attend the Annual Meeting in person, you may vote by signing and submitting your proxy card or by submitting your vote by telephone or the Internet. Whether or not you plan to attend the Annual Meeting, we urge you to vote by way of the Internet, by telephone, or by filling out and returning the proxy card. If you submit a proxy but do not give instructions as to how your shares should be voted on a particular proposal at the Annual Meeting, your shares will be voted in accordance with the recommendations of our board of directors stated in this Proxy Statement. Any proxy given pursuant to this solicitation may be revoked by the person giving it at any time before its use by (1) delivering a written notice of revocation addressed to TESARO, Inc., Attn: Corporate Secretary, 1000 Winter Street, Waltham, Massachusetts 02451, (2) a duly executed proxy bearing a later date, (3) voting again by the Internet or by telephone, or (4) attending the Annual Meeting and voting in person. Your last vote or proxy will be the vote or proxy that is counted. Attendance at the Annual Meeting will not cause your previously granted proxy to be revoked unless you specifically so request.

        If on the Record Date you held shares of our common stock in an account with a brokerage firm, bank, or other nominee, you are considered a beneficial owner of those shares and hold such shares in street name. These proxy materials have been forwarded to you by the nominee holding your shares. As a beneficial owner, you have the right to direct your broker, bank, or other nominee on how to vote the shares held in their account, and the nominee has enclosed or provided voting instructions for you to use in directing it how to vote your shares. The nominee that holds your shares, however, is considered the stockholder of record for purposes of the Annual Meeting. Because you are not the stockholder of record, you may not vote your shares in person at the Annual Meeting unless you bring a letter from your nominee confirming your beneficial ownership of the shares to the Annual Meeting. Whether or not you plan to attend the Annual Meeting, we urge you to vote by following your nominee's voting instructions to ensure that your vote is counted.

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        If you are a beneficial owner and do not direct your broker, bank, or other nominee on how to vote, and your broker, bank or other nominee does not have discretionary power to vote your shares, your shares may constitute "broker non-votes." Shares that constitute broker non-votes will be counted for the purpose of establishing a quorum at the Annual Meeting. Voting results will be tabulated and certified by the inspector of elections appointed for the Annual Meeting. If you receive more than one Proxy Statement, it is because you have shares that are registered in more than one name or are registered in different accounts. Please follow the instructions provided with each Proxy Statement received to ensure that all of your shares are voted.

        A list of stockholders of record as of the Record Date will be available for inspection during ordinary business hours at our offices located at 1000 Winter Street, Waltham, Massachusetts 02451, from April 16, 2018 to the date of our Annual Meeting. The list will also be available for inspection at the Annual Meeting.

Quorum Requirement for the Annual Meeting

        The presence at the Annual Meeting, whether in person or by valid proxy, of persons holding a majority of the shares of common stock outstanding on the Record Date will constitute a quorum, permitting us to conduct our business at the Annual Meeting. On the Record Date, there were 54,799,815 shares of common stock outstanding and entitled to vote, held by 28 stockholders of record. Abstentions (i.e., if you or your broker mark "ABSTAIN" on a proxy) and "broker non-votes" will be considered to be shares present at the meeting for purposes of a quorum. Broker non-votes occur when shares held by a broker for a beneficial owner are not voted with respect to a particular proposal and generally occur because the broker (1) does not receive voting instructions from the beneficial owner and (2) lacks discretionary authority to vote the shares. Brokers and other nominees have discretionary authority to vote on ratification of our independent registered public accounting firm for clients who have not provided voting instructions. However, without voting instructions from their clients, they cannot vote on "non-routine" proposals, such as the election of directors, the proposed amendment to our Non-Employee Director Compensation Policy, the approval of executive compensation, and the proposed amendment to our 2012 Employee Stock Purchase Plan.

Required Votes

        Election of directors.    Each director will be elected by the vote of the plurality of the votes of the shares present in person or represented by proxy at the meeting and entitled to vote on the election of directors. Abstentions and broker non-votes are not taken into account in determining the outcome of the election of directors. In addition, as further described below under the heading "Corporate Governance Matters," any nominee for director in an uncontested election who receives a greater number of votes "withheld" from his or her election than votes "for" such election shall, promptly following certification of the stockholder vote, offer his or her resignation to the board for consideration.

        Approval of the TESARO, Inc. Non-Employee Director Compensation Policy, including the non-employee director compensation amounts for 2018. Approval of the non-employee director compensation proposal requires the affirmative vote of the holders of at least a majority of the shares of common stock present in person or represented by proxy at the Annual Meeting, entitled to vote and voting on the matter. Abstentions and broker non-votes are not taken into account in determining the outcome of this proposal.

        Approval of executive compensation.    The affirmative vote from stockholders present in person or represented by proxy at the Annual Meeting representing a majority of the votes cast on the proposal is required to approve the Company's executive compensation. Abstentions and broker non-votes are

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not taken into account in determining the outcome of this proposal. As noted above, the proposal to approve the Company's executive compensation is non-binding.

        Approval of an amendment to the TESARO, Inc. 2012 Employee Stock Purchase Plan.    The affirmative vote from stockholders present in person or represented by proxy at the Annual Meeting representing a majority of the votes cast on the proposal is required to approve an amendment to the Company's 2012 Employee Stock Purchase Plan. Abstentions and broker non-votes are not taken into account in determining the outcome of this proposal.

        Ratification of our independent registered public accounting firm.    Approval of the proposal to ratify the audit committee's appointment of Ernst & Young as our independent registered public accounting firm for the fiscal year ending December 31, 2018 requires the affirmative vote of the holders of at least a majority of the shares of common stock present in person or represented by proxy at the Annual Meeting, entitled to vote and voting on the matter. Abstentions are not taken into account in determining the outcome of this proposal.

Solicitation of Proxies

        We will bear the cost of solicitation of proxies. This includes the charges and expenses of brokerage firms and others for forwarding solicitation material to beneficial owners of our outstanding common stock. We may solicit proxies by mail, personal interview, telephone or via the Internet through our officers, directors, and other management employees, who will receive no additional compensation for their services.

CORPORATE GOVERNANCE STANDARDS AND DIRECTOR INDEPENDENCE

        The board of directors has adopted Corporate Governance Guidelines (the "Guidelines"), a Code of Business Conduct and Ethics (the "Code of Ethics"), and a Policy for Related Person Transactions as part of our corporate governance practices and in accordance with rules of the Securities and Exchange Commission (the "SEC") and the listing standards of The NASDAQ Stock Market ("NASDAQ").

Corporate Governance Matters

        The Guidelines set forth a framework to assist the board of directors in the exercise of its responsibilities. The Guidelines cover, among other things, the duties and responsibilities of the directors; the composition, responsibilities and operation of the board of directors; the establishment and operation of board committees; succession planning for our Chief Executive Officer; convening executive sessions of independent directors; the board's interaction with management and third parties; director stock ownership guidelines; and the evaluation of the performance of the board and the Chief Executive Officer. In addition, under the Guidelines, any nominee for director in an uncontested election who receives a greater number of votes "withheld" from his or her election than votes "for" such election shall, promptly following certification of the stockholder vote, offer his or her resignation to the board for consideration. The independent members of the board will evaluate the best interests of the Company and decide the action to be taken with respect to such offered resignation, which may include: (i) accepting the resignation; (ii) maintaining the director but addressing what the independent directors believe to be the underlying cause or causes of the withheld votes; (iii) resolving that the director will not be re-nominated in the future for election; or (iv) rejecting the resignation.

        The Code of Ethics is designed to promote the highest standards of ethical conduct by our directors, executive officers, and employees. The Code of Ethics requires that our directors, executive officers and employees avoid conflicts of interest, comply with applicable laws and other legal requirements, conduct business in an honest and ethical manner and otherwise act with integrity and in our best interest. Under the terms of the Code of Ethics, directors, executive officers, and employees

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are required to report any existing or potential violation of the Code of Ethics of which they become aware. We intend to disclose future amendments to the Code of Ethics, or any waivers of its requirements, on our website or in filings under the Securities Exchange Act of 1934 (the "Exchange Act"), to the extent required by the applicable rules and exchange requirements.

        The Guidelines and Code of Ethics are available in the "Investors—Corporate Governance" section of our corporate website, which is www.tesarobio.com. The Guidelines and Code of Ethics are reviewed periodically by our governance and nominating committee, which recommends changes to our board of directors for approval as appropriate.

Certain Relationships and Related Person Transactions

Policies and Procedures for Related Person Transactions

        Under our Policy for Related Person Transactions, all related person transactions are reviewed and approved by our governance and nominating committee (or any other committee of the board of directors consisting of independent directors) or our full board of directors. This review covers any material transaction, arrangement or relationship, or any series of similar transactions, arrangements or relationships, in which we were or are to be a participant, the amount involved exceeds $120,000, and a related person had or will have a direct or indirect material interest, including, but not limited to, purchases of goods or services by or from a related person or entities in which the related person has a material interest, and indebtedness, guarantees of indebtedness and employment by us of a related person. A "related person," as determined since the beginning of our last fiscal year, is any executive officer, director or nominee to become director, a holder of more than 5% of our common stock, including any immediate family members of such a person, or any entity owned or controlled by such a person.

Related Person Transactions

        Since January 1, 2017, we have not been a party to any transaction and there are no currently proposed transactions in which the amount involved exceeded or will exceed $120,000, and in which any of our executive officers, directors or holders of more than 5% of any class of our common stock, or an affiliate or immediate family member thereof, had or will have a direct or indirect material interest, other than compensation, termination and change in control arrangements, which are described below under "Non-Employee Director Compensation," "Director Compensation" and "Compensation of Executive Officers."

Board Independence and Leadership Structure

        Our board of directors believes, and NASDAQ Marketplace Rules require, that a majority of its members should be independent directors. In addition, each of the audit, compensation, and governance and nominating committees is currently required by its charter to be comprised solely of independent directors. Consistent with NASDAQ's independence criteria, the board of directors has affirmatively determined that each of our directors and nominees for director other than Leon O. Moulder, Jr., who is our Chief Executive Officer, and Mary Lynne Hedley, Ph.D., who is our President and Chief Operating Officer, is independent of TESARO and our management. NASDAQ's independence criteria includes a series of objective tests, including that the director is not an employee of TESARO and has not engaged in various types of business dealings with us. In addition, as further required by NASDAQ rules, the board of directors has subjectively determined as to each independent director and nominee for director that no relationship exists that, in the opinion of the board of directors, would interfere with each such person's exercising independent judgment in carrying out his or her responsibilities as a director. In making these determinations on the independence of our directors and nominees for director, the board of directors considered the relationships that each such

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director or nominee has with the Company and our management and all other facts and circumstances the board deemed relevant in determining independence, including the beneficial ownership of our capital stock by each such person.

        In accordance with the Guidelines, the independent members of our board of directors meet in "executive session" at least quarterly. If the Chairperson of the board is not an independent director, the Guidelines provide that the Lead Director, as selected by the independent directors, will preside over and develop the agenda for these sessions. The purpose of the executive sessions is to promote open and candid discussion among non-employee directors.

        The Guidelines require the board of directors to elect its Chairperson based on the board's view of what is best for the Company at the time of the election. Although neither the Company's bylaws nor the Guidelines require separating the positions of Chairperson of the board of directors and Chief Executive Officer, the board believes that having separate positions is the appropriate current leadership structure for the Company, and the positions of the Chairperson of the board of directors and Chief Executive Officer are currently separated. Separating these positions allows our Chief Executive Officer to focus on our day-to-day business, while allowing the Chairperson of the board of directors to lead the board in its fundamental role of providing advice to, and independent oversight of, management. The board of directors recognizes the time, effort, and energy that the Chief Executive Officer must devote to his position in the current business environment, as well as the commitment required to serve as our Chairperson. The board believes that this structure ensures an appropriate role for the independent directors in the oversight of the Company and active participation of the independent directors in setting agendas and establishing priorities and procedures for the work of our board of directors. The board recognizes that other leadership models could also be appropriate, and the governance and nominating committee is required by its charter to periodically review the leadership structure and provide recommendations to the board.

Board's Role in Risk Oversight

        The board of directors believes that risk management is an important part of establishing, updating, and executing on the Company's business strategy. The board, both as a whole and at the committee level, has oversight responsibility relating to risks that could affect the corporate strategy, business objectives, compliance, operations, financial condition, and performance of the Company. The board focuses its oversight on the most significant risks facing the Company and on the Company's processes to identify, prioritize, assess, manage, and mitigate those risks. The board and its committees receive regular reports from members of the Company's senior management on areas of material risk to the Company, including strategic, operational, financial, legal, and regulatory risks. While the board has an oversight role, management has direct responsibility for managing and assessing risks and implementing processes and controls to mitigate their effects on the Company.

        The board of directors carries out its oversight responsibilities in part through its committees. The audit committee, as part of its responsibilities, oversees the management of financial risks, including but not limited to accounting matters, liquidity and credit risks, corporate tax positions, insurance coverage, and cash investment strategy and results. The audit committee also oversees the management of risks relating to the performance of the Company's independent registered public accounting firm, our systems of internal control over financial reporting and disclosure controls and procedures, and management of cybersecurity risks. The compensation committee is responsible for overseeing the management of risks relating to our executive compensation and overall compensation and benefit strategies, plans, arrangements, practices and policies, and compensation of the board of directors. The governance and nominating committee oversees the management of risks associated with overall compliance and corporate governance practices, and the independence and composition of the board. These committees provide regular reports to the full board.

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Meetings of the Board of Directors and its Committees

        The board of directors and its committees meet regularly throughout the year and hold special meetings from time to time. The board held 12 meetings during the year ended December 31, 2017. During this time, each of our directors attended at least 75% of the aggregate number of meetings held by the board and all committees of the board on which such director served (during the period that such director served). The board has adopted a policy that encourages, but does not require, attendance by our board members at our annual meetings of stockholders. All of the members of the board attended the 2017 annual meeting of stockholders.

BOARD COMMITTEES AND THEIR FUNCTIONS

        The board of directors has three standing committees: the audit committee; the compensation committee; and the governance and nominating committee. The charters for these committees can be accessed electronically on the "Investors—Corporate Governance" section of our corporate website, which is www.tesarobio.com. Information concerning these committees is set forth below. Each board committee currently consists only of directors who are independent.

        The Guidelines require the board of directors to conduct, and the governance and nominating committee to oversee, an annual evaluation of the board's operations and performance in order to enhance its effectiveness. Pursuant to the Guidelines, following this evaluation, the governance and nominating committee is required to make recommendations to the full board for its consideration. Each committee also conducts an annual evaluation of the performance of its duties under its respective charter.

        The following table presents the current composition of the standing committees of the board of directors and the number of committee meetings held during the year ended December 31, 2017:

Audit Committee

        The board of directors has established a separately designated standing audit committee in accordance with Section 3(a)(58)(A) of the Exchange Act. The audit committee is responsible for assisting the board in its oversight of the integrity of our financial statements, the qualifications and independence of our independent auditors, and our internal financial and accounting controls. The

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audit committee has direct responsibility for the appointment, compensation, retention (including termination) and oversight of our independent auditors, which are currently Ernst & Young, and our independent auditors report directly to the audit committee. The audit committee also prepares the audit committee report that the SEC rules require to be included in this Proxy Statement, and is responsible for overseeing the integrity of our information systems, processes and data, including cybersecurity.

        The members of the audit committee are Mr. Alleva, Mr. Nicholson, and Dr. Seidenberg. Under NASDAQ's applicable corporate governance standards and Rule 10A-3 under the Exchange Act, the audit committee must be comprised solely of independent directors. Mr. Alleva, Mr. Nicholson, and Dr. Seidenberg each qualifies as an independent director under NASDAQ's corporate governance standards and the independence requirements of Rule 10A-3 of the Exchange Act. The board has determined that Mr. Alleva and Mr. Nicholson each qualifies as an "audit committee financial expert" as such term is currently defined in Item 407(d)(5) of Regulation S-K. Each member of the audit committee is able to read and understand fundamental financial statements, including our balance sheet, statement of operations, and statement of cash flows.

Compensation Committee

        The compensation committee approves the compensation objectives for the Company, provides a recommendation on the compensation of the Chief Executive Officer, which is subject to approval by the independent members of the full board of directors, and establishes the compensation for other executives with a title of Senior Vice President or higher. The compensation committee reviews all compensation components for these executives, including base salary, bonus, benefits, and other perquisites. The compensation committee may delegate any of its responsibilities to one or more subcommittees as the committee deems appropriate. See "Compensation Discussion & Analysis—Compensation Setting Process" below for more information regarding the roles of the compensation committee, the board, and compensation consultants in determining or recommending the amount or form of executive compensation.

        The members of the compensation committee are Mr. Mott, Dr. Armitage, and Mr. Collier. Each member of the compensation committee is a non-employee director within the meaning of Rule 16b-3 of the rules promulgated under the Exchange Act, an outside director, as defined by Section 162(m) of the Internal Revenue Code (the "Code"), and an independent director, as defined by NASDAQ.

Governance and Nominating Committee

        The governance and nominating committee is responsible for making recommendations to the board of directors regarding candidates for directorships and the size and composition of the board of directors. In addition, the governance and nominating committee is responsible for overseeing the Guidelines and our overall compliance practices and reporting and making recommendations to the board concerning corporate governance matters. See "Director Nominations and Communication with Directors" below for information about the governance and nominating committee's policy regarding nominations of directors by stockholders.

        The members of the governance and nominating committee are Mr. Mott, Mr. Collier, and Dr. Patel. Each member of the governance and nominating committee is a non-employee director within the meaning of Rule 16b-3 of the rules promulgated under the Exchange Act and an independent director, as defined by NASDAQ.

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DIRECTOR NOMINATIONS AND COMMUNICATION WITH DIRECTORS

Director Nomination Process

        The governance and nominating committee recommends, and the board of directors nominates, candidates to stand for election as directors. Stockholders may also nominate persons to be elected as directors. In order to nominate a person for election as director, a stockholder must follow the procedures contained in our bylaws and satisfy the requirements of Regulation 14A of the Exchange Act. To nominate a person to stand for election as a director at the annual meeting of stockholders for 2019, a stockholder must provide our Corporate Secretary with timely notice of the nomination. To be timely, the stockholder's notice must be delivered to, or mailed and received by us not later than 90 days, nor earlier than 120 days prior to the anniversary date of the preceding year's annual meeting, except that if the annual meeting is set for a date that is not within 30 days before or 60 days after such anniversary date, we must receive the notice not earlier than the 120th day prior to such annual meeting and not later than the 90th day prior to such annual meeting or the 10th day following the day on which we provide the notice or public disclosure of the date of the meeting. The notice must include the following information:

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As to the stockholder giving the notice and the beneficial owner, if any, on whose behalf the nomination or proposal is made:



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the name and address of the stockholder and of such beneficial owner, if any;



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the class and number of shares of our capital stock owned beneficially and of record by such stockholder and such beneficial owner, if any;



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if applicable, a description of all agreements, arrangements or understandings with respect to the nomination or proposal between or among such stockholder and such beneficial owner, if any, any of their respective affiliates or associates, and any others acting in concert with the foregoing;



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if applicable, a description of all agreements, arrangements or understandings (including any derivative or short positions, profit interests, options, warrants, stock appreciation or similar rights, hedging transactions, and borrowed or loaned shares) that have been entered into as of the date of the stockholder's notice by, or on behalf of, such stockholder and such beneficial owner, if any, the effect or intent of which is to mitigate loss, manage risk or benefit of share price changes for, or increase or decrease the voting power of, such stockholder and such beneficial owner, if any, with respect to our shares of stock;



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such other information relating to such stockholder and such beneficial owner, if any, as would be required to be included in a proxy statement or other filings to be made in connection with solicitations of proxies for the election of directors in a contested election under the SEC's proxy rules;



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a representation that the stockholder is a holder of record of our stock, is entitled to vote at such meeting, and intends to appear in person or by proxy at the meeting to propose such business or nomination;



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a representation whether the stockholder or the beneficial owner, if any, intends, or is part of a group that intends, (a) to deliver a proxy statement and/or form of proxy to holder of at least the percentage of our outstanding capital stock required to approve or adopt the proposal or elect the nominee(s) and/or (b) otherwise to solicit proxies from stockholders in support of such proposal or nomination; and



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such other information that the board of directors may request in its discretion.

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As to each person whom a stockholder proposes to nominate for election as a director:



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such person's name, age, business address and, if known, residential address;



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such person's principal occupation or employment;



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the class, series and number of shares of our stock that is, directly or indirectly, owned, beneficially or of record, by such person;



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a description of all agreements, arrangements or understandings between the stockholder and each nominee and any other person or persons, naming such person or persons, pursuant to which the nomination is to be made by the stockholder;



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such other information regarding each nominee as would be required to be included in a proxy statement filed under the SEC's proxy rules if the nominee had been nominated, or intended to be nominated, by the board of directors; and



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the consent of each nominee to be named in the proxy statement as a nominee and to serve as a director if elected.

        Each director will be elected by the vote of the plurality of the votes of the shares present in person or represented by proxy at the meeting and entitled to vote on the election of directors. However, pursuant to our Corporate Governance Guidelines, any nominee for director in an uncontested election who receives a greater number of votes "withheld" from his or her election than votes "for" such election shall, promptly following certification of the stockholder vote, offer his or her resignation to the board for consideration.

        Additional information regarding requirements for stockholder nominations for next year's annual meeting is described in this Proxy Statement under "General Matters—Stockholder Proposals and Nominations."

Contacting the Board of Directors

        Stockholders wishing to communicate with our board of directors may do so by writing to the board, Chairperson of the board or the non-employee members of the board as a group, at:

TESARO, Inc.
1000 Winter Street
Waltham, Massachusetts 02451
Attention: Corporate Secretary

        The communication must prominently display the legend "BOARD COMMUNICATION" in order to indicate to the Corporate Secretary that it is a communication for the board. Upon receiving such a communication, the Corporate Secretary will promptly forward the communication to the relevant individual or group to which it is addressed. The board has requested that certain items that are unrelated to the board's duties and responsibilities should be excluded, such as spam, junk mail and mass mailings, resumes and other forms of job inquiries, surveys, and business solicitations or advertisements.

        The Corporate Secretary will not forward any communication determined in his or her good faith belief to be frivolous, unduly hostile, threatening, illegal or similarly unsuitable. The Corporate Secretary maintains a list of each communication that was not forwarded because it was determined by the Corporate Secretary to be frivolous. Such list is delivered to the Chairperson of the board at each quarterly meeting of the board (and made available to each other member of the board). In addition, each communication subject to this policy that was not forwarded because it was determined by the Corporate Secretary to be frivolous is retained in the Company's files and made available at the request of any member of the board to whom such communication was addressed.

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PROPOSAL NO. 1—ELECTION OF DIRECTORS

        Our nominees for the election of directors at the Annual Meeting include eight independent non-employee directors, our Chief Executive Officer and our President and Chief Operating Officer. Each director is elected to serve a one-year term, with all directors subject to annual election. At the recommendation of the governance and nominating committee, the board has nominated the following persons to serve as directors for the term beginning at the Annual Meeting on May 10, 2018: Leon O. Moulder, Jr.; Mary Lynne Hedley, Ph.D.; David M. Mott; Lawrence M. Alleva; James O. Armitage, M.D.; Earl M. (Duke) Collier, Jr.; Garry A. Nicholson; Kavita Patel, M.D.; Beth Seidenberg, M.D.; and Pascale Witz. All of the nominees are currently serving on the board other than Ms. Witz. Arnold L. Oronsky, who has served on the board since 2011, is not nominated for re-election in this Proxy Statement.

        It is intended by the persons named as proxies that proxies received in response to this solicitation will be voted FOR the election of each nominee named in this section unless (a) otherwise stated in the proxy or (b) in the case of a broker non-vote with respect to the proposal. Proxies submitted for the Annual Meeting can only be voted for those nominees named in this Proxy Statement. If, however, any director nominee is unable or unwilling to serve as a nominee at the time of the Annual Meeting, the persons named as proxies may vote for a substitute nominee designated by the board of directors, or the board may reduce the size of the board. Each nominee has consented to serve as a director if elected, and the board does not believe that any nominee will be unwilling or unable to serve. Each director will hold office until his or her successor is duly elected and is qualified or until his or her earlier death, resignation or removal.

Criteria for Evaluating Director Nominees

        The board of directors provides strategic direction to the Company and oversees the performance of the Company's business and management. The governance and nominating committee periodically identifies and reviews with the board desired skills and attributes of both individual board members and the overall board within the context of current and future needs. The governance and nominating committee develops the general criteria, subject to approval by the full board, for identifying, evaluating and selecting qualified candidates for election or re-election to the board. The governance and nominating committee reviews the appropriate skills and characteristics required of directors in the context of the current composition of the board (including its diversity, the overall tenure of the directors, and whether any directors have reached the age of 72 and are due to be considered for retirement), our operating requirements and the long-term interests of our stockholders. The committee may use outside consultants to assist in identifying candidates. We engaged Perspective Group, a third-party executive search and consulting firm serving the life sciences and healthcare industries, to help identify Ms. Witz. Among the characteristics the committee may consider are the collective knowledge and diversity of professional skills and background, experience in relevant industries, age and geographic background, in addition to the qualities of integrity, judgment, acumen, and the time and ability to work professionally and effectively with other board members and management and make a constructive contribution to the board. The committee considers candidates submitted by directors and management, as well as candidates recommended by stockholders, which are evaluated in the same manner as other candidates identified to it. Final approval of director candidates is determined by the full board.

        The board has determined that all of our current directors and nominees are qualified to serve as directors of the Company.

        The name of each nominee for director, each nominee's age as of April 1, 2018, and other information about each nominee is shown below. In addition, the biography of each of the nominees below contains information regarding the experiences, qualifications, attributes or skills that caused the

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governance and nominating committee and the board to determine that the person should serve as a director of the Company.

        Leon (Lonnie) O. Moulder, Jr. has served as Chief Executive Officer and as a member of our board of directors since co-founding the Company in March 2010. From April 2009 to January 2010, Mr. Moulder served as vice chairman of the board of directors and president and chief executive officer of Abraxis BioScience, Inc., a biotechnology company. Before that, Mr. Moulder served as vice chairman of Eisai Corporation of North America, from January 2008 until January 2009, following Eisai Co. Ltd.'s acquisition of MGI PHARMA, Inc., a pharmaceutical company, in January 2008. Mr. Moulder served as president and chief executive officer and as a member of the board of directors of MGI PHARMA, Inc. from May 2003 through January 2008. Mr. Moulder joined MGI PHARMA, Inc. in September 1999 as executive vice president and was promoted to president and chief operating officer in May 2002. Mr. Moulder earned a bachelor of science degree in pharmacy from Temple University and a master of business administration degree from the University of Chicago. Mr. Moulder currently serves as chairman of the board of directors of Trevena, Inc. (NASDAQ: TRVN), as a trustee of Temple University, and is on the board of the Fox Chase Cancer Center. Mr. Moulder also served as a director of Cubist Pharmaceuticals, Inc. through the sale of the company to Merck & Co., Inc. in 2015. The board of directors believes Mr. Moulder's perspective and experience as our co-founder and Chief Executive Officer, his depth of operating and senior management experience in our industry and his experience serving on the boards of directors of public and private companies in the life sciences industry provide him with the qualifications and skills to serve as a director.

        Mary Lynne Hedley, Ph.D. has served as our President and as a member of our board of directors since co-founding the Company in March 2010. She also served in the role of Chief Scientific Officer from the Company's founding until she became Chief Operating Officer in July 2014. From July 2009 to February 2010, Dr. Hedley served as executive vice president of operations and chief scientific officer of Abraxis BioScience, Inc. Dr. Hedley served as executive vice president of Eisai Corporation of North America from January 2008 until July 2009, following Eisai Co. Ltd.'s acquisition of MGI PHARMA, Inc. in January 2008. Dr. Hedley served in various positions at MGI PHARMA, Inc. from 2004 through its acquisition in January 2008, most recently as executive vice president and chief scientific officer. Prior to that, Dr. Hedley co-founded and served as the president and chief executive

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officer of ZYCOS, Inc., a biotechnology company, which was acquired by MGI PHARMA, Inc. in 2004. Before co-founding ZYCOS, Dr. Hedley completed two consecutive postdoctoral fellowships at Harvard University. Dr. Hedley earned a bachelor of science degree in microbiology from Purdue University and a doctoral degree in immunology from the University of Texas, Southwestern Medical Center. Dr. Hedley currently serves on the boards of directors of bluebird bio, Inc. (NASDAQ: BLUE), Millendo Therapeutics, Inc. and Youville Place, Inc. She also served on the board of directors of Receptos, Inc. prior to its acquisition by Celgene Corp. in August 2015. The board of directors believes Dr. Hedley's perspective and experience as our co-founder and President, her educational background and her operating and management experience in the life sciences industry provide her with the qualifications and skills to serve as a director.

        David M. Mott has served on our board of directors since May 2010 and as the Chairperson of the board of directors since July 2011. Mr. Mott has served as a general partner of New Enterprise Associates ("NEA"), an investment firm focused on venture capital and growth equity investments, since September 2008, where he leads the healthcare investing practice. From 1992 until 2008, Mr. Mott worked at MedImmune Limited, a biotechnology company and subsidiary of AstraZeneca Plc, and served in numerous roles during his tenure including from October 2000 through July 2008 as president and chief executive officer, and previously as chief financial officer, and as president and chief operating officer. During that time, Mr. Mott also served as executive vice president of AstraZeneca Plc from June 2007 to July 2008 following AstraZeneca's acquisition of MedImmune in June 2007. Prior to joining MedImmune, Mr. Mott was a vice president in the healthcare investment banking group at Smith Barney, Harris Upham & Co. Inc. Mr. Mott received a Bachelor of Arts degree from Dartmouth College. In connection with his role at NEA, Mr. Mott serves on the boards of various companies. Mr. Mott serves on the boards of the following public companies, all of which are companies in which NEA continues to be invested: Adaptimmune Therapeutics plc (NASDAQ: ADAP), Mersana Therapeutics, Inc. (NASDAQ: MRSN), Ardelyx, Inc. (NASDAQ: ARDX), Epizyme, Inc. (NASDAQ: EPZM), and Nightstar Therapeutics plc (NASDAQ: NITE). Mr. Mott is chairman of the board of each of these companies, other than Nightstar Therapeutics. Mr. Mott previously served on the board of directors of Omthera Pharmaceuticals from March 2011 until July 2013, Clementia Pharmaceuticals from June 2015 until February 2018, and Prosensa Holding, B.V. from January 2012 until January 2015. The board of directors believes Mr. Mott's experience in the life sciences industry as a senior executive and venture capitalist and his service on the boards of directors of other life sciences companies provide him with the qualifications and skills to serve as a director.

        Lawrence M. Alleva has served on our board of directors since March 2012. Mr. Alleva is currently retired. Prior to his retirement in June 2010, Mr. Alleva was employed by PricewaterhouseCoopers LLP ("PwC"), for 39 years, including 28 years as a partner with the firm. Mr. Alleva served clients primarily in the technology sector, including pharmaceutical and biotechnology companies. Additionally, he served in a variety of office and regional practice leadership roles, most recently as ethics and compliance leader (assurance) for PwC from 2006 until his retirement. Mr. Alleva is a Certified Public Accountant (inactive). Mr. Alleva received a bachelor of science degree in accounting from Ithaca College and attended the Columbia University Executive MBA (non-degree) Program. Mr. Alleva also serves as a director for Adaptimmune Therapeutics plc (NASDAQ: ADAP), Bright Horizons Family Solutions Inc. (NYSE: BFAM) and Mersana Therapeutics (NASDAQ: MRSN). Mr. Alleva also served as a director of Mirna Therapeutics, Inc. (now known as Synlogic, Inc.) from July 2014 to August 2017. The board of directors believes Mr. Alleva's extensive experience and expertise working with public companies on corporate finance and accounting matters as a Certified Public Accountant (inactive), his experience serving on other corporate boards, and his experience in a senior leadership role at PwC provide him with the qualifications and skills to serve as a director.

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        James O. Armitage, M.D. has served on our board of directors since May 2013. Dr. Armitage has been a professor of internal medicine in the division of hematology and oncology at the University of Nebraska Medical Center since 2003, after having served as chairman of the department of internal medicine, dean of the college of medicine, and in various other capacities since joining the Center in 1982. He also holds a hospital appointment at The Nebraska Medical Center. Dr. Armitage has authored or co-authored more than 600 articles, 108 book chapters and edited or co-edited 27 textbooks. He has previously served as president of the American Society of Clinical Oncology ("ASCO"), and as a member of the ASCO board of directors. Dr. Armitage received a bachelor of science degree from the University of Nebraska and a medical degree from the University of Nebraska Medical Center and completed his post-graduate training at the University of Nebraska Medical Center and the University of Iowa Hospitals and Clinics. The board of directors believes that Dr. Armitage's training as a physician, his research, clinical and administrative experience, and his previous service as a director of a publicly traded biopharmaceutical company provide him with the qualifications and skills to serve as a director.

        Earl M. (Duke) Collier, Jr. has served on our board of directors since May 2014. He has served as President of The Braxton Company, a healthcare strategy consulting firm, since 2015. From 2010 to 2014, Mr. Collier served as chief executive officer of 480 Biomedical and executive chair of Arsenal Medical, Inc., both of which are polymer biotherapeutics companies focused on serious clinical problems unable to be solved by current therapies. Mr. Collier was president at deCODE genetics, Inc., a biopharmaceutical company, from 2009 to 2010, and was executive vice president at Genzyme Corporation ("Genzyme"), a biotechnology company acquired by Sanofi S.A. in 2011, from 1997 to 2009. During his tenure at Genzyme, Mr. Collier was responsible for building the biosurgery, oncology and cardiovascular businesses and overseeing the company's efforts in multiple sclerosis. He also led some of Genzyme's significant acquisitions and the formation of MG Biotherapeutics, a Genzyme joint venture that focused on cardiac cell therapy. He also has served as president of Vitas Healthcare, a hospice provider, a partner at the law firm of Hogan & Hartson LLP, and deputy administrator of the Health Care Finance Administration (now Centers for Medicare & Medicaid Services) in the U.S. Department of Health & Human Services. Mr. Collier received a bachelor of arts degree from Yale University and a law degree from the University of Virginia Law School. Mr. Collier serves on the board of directors of Capricor Therapeutics (OTC: CAPR), a regenerative medicine company, and the Board of Trustees of the Boston Athenaeum. He is also chairman of the board of trustees of Newton-Wellesley Hospital, serves on the board of Partners HealthCare System and is chair of the Innovation Advisory Board of Partners Healthcare Innovation. The board of directors believes Mr. Collier's experience in the life sciences industry as a senior executive and his service on the boards of directors of other life sciences companies provide him with the qualifications and skills to serve as a director.

        Garry A. Nicholson has served on our board of directors since May 2015. Mr. Nicholson is currently retired and serves on the board of directors of biopharmaceutical company Five Prime Therapeutics, Inc. (NASDAQ: FPRX). He served as president and chief executive officer of XTuit Pharmaceuticals, Inc., a biopharmaceutical company, from September 2015 to October 2016. Prior to that, he served as president, Pfizer Oncology, from May 2008 until March 2015. He joined Pfizer, Inc. ("Pfizer"), as the first leader of its global, dedicated oncology business, with direct responsibility for business strategy and operations. He was responsible for clinical development for both early and late stage medicines, for all oncology sales and marketing organizations globally, and for licensing, acquisitions, and the oncology therapeutic area strategy. In addition to his oncology role, he was a member of the Portfolio Strategy and Investment Committee, the governance body with the oversight responsibility for Pfizer research and development. He also served as a member of the Pfizer Foundation board of directors. Prior to joining Pfizer, Mr. Nicholson worked at Eli Lilly and Company ("Lilly"), in a number of leadership roles, including sales management, marketing, human resources, and as the pharmaceutical commercial leader in Italy. He assumed responsibility for the sales and marketing of Lilly's cancer products in the U.S. in 1996 and subsequently managed oncology drug

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development. Mr. Nicholson earned a bachelor of science degree in pharmacy from the University of North Carolina, Chapel Hill, and a master of business administration degree from the University of South Carolina, Columbia. Mr. Nicholson has also served on the board of directors of SQZ Biotech, a cell therapy company, since December 2015. The board of directors believes Mr. Nicholson's extensive experience in the pharmaceutical industry as a senior executive provide him with the qualifications and skills to serve as a director.

        Kavita Patel, M.D. has served on our board of directors since March 2016. Dr. Patel has been a Non-Resident Senior Fellow at The Brookings Institution, a premier research and thought leadership organization, since January 2011. In this role, Dr. Patel provides senior level vision and guidance for the Center for Health Policy in the Department of Economic Studies of the Institution, specifically helping healthcare systems understand how to transform their clinical environments to become more accountable for the care they provide. Dr. Patel has also been a practicing primary care physician at Johns Hopkins since January 2011. From 2009 to 2010, she served as Director of Policy for the Office on Intergovernmental Affairs and Public Engagement at The White House. Prior to that, she served as Deputy Staff Director for Health for Senator Edward M. Kennedy from 2007 to 2009. Dr. Patel currently serves as a member of the board of directors of SSM Healthcare, a nonprofit integrated delivery system, Community Catalyst, a national advocacy organization, and the National Initiative for Children's Healthcare Quality. She is also a member of the advisory board for the National Commission on Physician Payment Reform, the Robert Graham Center for Policy Studies in Family Medicine and Primary Care, and the Johns Hopkins Medicine Sibley Hospital Innovation Hub. Dr. Patel earned her bachelor of arts from the University of Texas at Austin, her M.D. from the University of Texas Health Science Center, and her master of science in health sciences from the University of California, Los Angeles. The board of directors believes Dr. Patel's years of healthcare leadership experience and clinical work in primary care, research, innovation, policy and advocacy provide her with the qualifications and skills to serve as a director.

        Beth Seidenberg, M.D. has served on our board of directors since June 2011. Dr. Seidenberg has been a partner at Kleiner Perkins Caufield & Byers, a venture capital firm, since May 2005, where she has primarily focused on life science investing. Dr. Seidenberg was previously the senior vice president, head of global development and chief medical officer at Amgen, Inc., a biotechnology company. In addition, Dr. Seidenberg was a senior executive in research and development at Bristol Myers Squibb Company, a biopharmaceutical company, and Merck & Co., Inc., a healthcare company. Dr. Seidenberg received a bachelor of science degree from Barnard College and a medical degree from the University of Miami School of Medicine and completed her post-graduate training at Johns Hopkins University and the National Institutes of Health. Dr. Seidenberg serves on the boards of directors of ARMO BioSciences (NASDAQ: ARMO), Atara Biotherapeutics, Inc. (NASDAQ: ATRA), Epizyme, Inc. (NASDAQ: EPZM) and several privately held life sciences companies. The board of directors believes Dr. Seidenberg's training as a physician and her experience in the life sciences industry as a senior executive and venture capitalist provide her with the qualifications and skills to serve as a director.

        Pascale Witz is nominated for election to our board of directors at the Annual Meeting. Ms. Witz would bring nearly three decades of pharmaceutical and healthcare management experience to our board. She currently serves as founder and president of PWH Advisors, providing consulting and advisory services to life sciences companies and investors. From 2013 to 2016, Ms. Witz served at Sanofi SA in a number of senior executive roles, including as executive vice president, global diabetes and cardiovascular. Prior to joining Sanofi, Ms. Witz served more than 17 years at GE Healthcare, including as president and chief executive officer of its medical diagnostics business. Ms. Witz serves on the board of directors for PerkinElmer, Inc. (NYSE: PKI), Horizon Pharma Plc (NASDAQ: HZNP), Regulus Therapeutics, Inc. (NASDAQ: RGLS), Fresenius Medical Care AG & Co. KGaA (NYSE: FMS) and Savencia SA (Euronext Paris: SAVE.PA). Ms. Witz plans to cease serving on the board of Savencia prior to the Annual Meeting. Ms. Witz earned her Master of Business Administration in

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Economics and Marketing from INSEAD and her Master of Science in Biochemistry from INSA Lyon. The board of directors believes Ms. Witz's years of experience in the pharmaceutical and healthcare industry as both a senior executive and board member provide her with the qualifications and skills to serve as a director.

Required Vote and Board Recommendation

        In order to be elected as a director, a nominee must be elected by a plurality of the votes of the shares present in person or represented by proxy at the meeting and entitled to vote on the election of directors at the Annual Meeting. Stockholders do not have the right to cumulate their votes in the election of directors. In addition, any nominee for director in an uncontested election who receives a greater number of votes "withheld" from his or her election than votes "for" such election shall, promptly following certification of the stockholder vote, offer his or her resignation to the board for consideration.

        THE BOARD RECOMMENDS A VOTE "FOR" ELECTION OF EACH OF THE TEN NOMINATED DIRECTORS.

Non-Employee Director Compensation

        The current compensation program for our non-employee directors, which was in place for all of 2017, is set forth in the chart below. Under this policy, non-employee directors receive a base retainer for their service on the board of directors and fees for certain service and attendance. Non-employee directors are permitted to elect to receive their retainer and fees in cash or unrestricted common stock and are also permitted to elect to defer the receipt of that stock to a date selected by the director or to the date of termination of their service as a director.

        The amounts described in the chart above are paid in a single payment on the first business day of the month following our annual meeting.

        In 2017, each incumbent non-employee director received an annual award of options to purchase 12,000 shares of our common stock, which vests on the earlier of the one-year anniversary of the date of grant and the date of our next annual meeting, subject to the director's continued service on the board of directors. In addition, in 2017, any newly-appointed non-employee director would have been eligible to receive a one-time initial award of options to purchase 24,000 shares of our common stock, which vest annually over a three-year period, subject to the director's continued service on the board of directors.

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        In February 2018, the board, based on the unanimous recommendation of the compensation committee of the board, approved a revised Non-Employee Director Compensation Policy, including specific compensation amounts for 2018 and overall caps on director compensation, subject to approval by our stockholders. See "PROPOSAL NO. 2—Approval of the Non-Employee Director Compensation Policy, including Compensation Amounts for 2018."

Director Compensation

        The following table summarizes the compensation paid to or earned by our non-employee directors during the year ended December 31, 2017:

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        The following table sets forth, as of December 31, 2017, the aggregate number of exercisable and unexercisable option awards outstanding held by our current non-employee directors:

Director and Officer Stock Ownership Guidelines

        We believe that it is important that directors focus on long-term stockholder value and that their interests are aligned with those of our stockholders. Our stock ownership guidelines require each director to hold shares of our common stock with a value equal to three times the amount of the annual base retainer fee paid to directors for service on the board. This amount will be re-calculated whenever there is a change in the annual base retainer fee. Additionally, our amended stock ownership guidelines, effective May 11, 2017, require (i) our CEO and our President to hold shares of our common stock with a value equal to at least five times the amount of his or her annual base salary, and (ii) each officer with a title of Senior Vice President or higher who is required to report ownership of the Company's equity securities in accordance with Section 16(a) of the Securities Exchange Act of 1934, as amended ("Section 16 Officers"), to hold shares of our common stock with a value equal to at least one and a half times the amount of his or her annual base salary. For this purpose, "value" includes both the market value of shares held directly by such director or officer, or through a trust (including where the delivery of such shares is deferred to a future date following the vesting date by election of the officer or director), and 60% of the value of any vested, in-the-money stock options issued under any Company equity compensation plan. Each director is required to achieve the applicable level of ownership by the later of the date of our 2019 annual meeting and the date that is three years after the date on which the person became a director. Each officer covered by the guidelines is required to achieve the applicable level of ownership by the later of the date of our 2022 annual meeting and the date that is five years after the date on which the person became an officer.

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PROPOSAL NO. 2—APPROVAL OF THE NON-EMPLOYEE DIRECTOR COMPENSATION POLICY, INCLUDING COMPENSATION AMOUNTS FOR 2018

        We are asking our stockholders to approve the TESARO, Inc. Non-Employee Director Compensation Policy ("Director Compensation Policy"), which will impose an annual limit for three years on the aggregate cash and equity incentive compensation that may be awarded to non-employee directors by the Company, as well as establish the specific compensation amounts payable to non-employee directors for calendar year 2018.

        The following summary of the material terms of the Director Compensation Policy is qualified in its entirety by reference to the full text of the Director Compensation Policy, a copy of which is attached as Appendix A to this proxy statement and which is incorporated by reference into this proposal. Stockholders should refer to Appendix A for a more complete description of the Director Compensation Policy.

Aggregate Limits on Compensation for 2018 through 2020

        The Director Compensation Policy provides that, for the three-year period commencing with calendar year 2018 and ending with calendar year 2020, (i) the total annual compensation, including all cash and equity components (based on grant date fair market value), paid to any incumbent non-employee director during any single calendar year shall not exceed $1,000,000, and (ii) the total annual compensation, including all cash and equity components (based on grant date fair market value), paid to any newly appointed non-employee director during any single calendar year shall not exceed $2,000,000 within the calendar year of first being appointed.

Compensation Payable for Calendar Year 2018

        The Director Compensation Policy provides that each non-employee director shall be entitled to the payments described below while serving as a director for calendar year 2018. After calendar year 2018, these retainers, fees and grants may be modified for years after 2018 by the compensation committee or the board in their discretion, subject to the general compensation limits described above.

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        During calendar year 2018, the Company will not provide additional compensation to non-employee directors, other than as provided under this Policy, unless such additional compensation is in exchange for bona fide services or is otherwise reviewed and approved in accordance with the Company's Related Party Transaction Policy then in effect.

        The Company intends to transition from its historical practice of an annual equity award consisting only of stock options to an annual equity award comprised of a mix of RSUs and stock options.

Rationale for the Director Compensation Policy

        The proposed Director Compensation Policy is designed to align the Company's non-employee director compensation policies with evolving governance and compensation practices, as well as to attract and retain qualified independent directors to our board. Specifically, in establishing the amounts payable under the Director Compensation Policy, the compensation committee worked with its independent consultant, Pearl Meyer & Partners, LLC, to identify compensation trends in

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non-employee director compensation and amounts payable to non-employee directors by peer companies. The compensation payable for calendar year 2018 under the proposed Director Compensation Policy is in line with the median of peer non-employee director compensation programs presented by Pearl Meyer, and our board believes the proposed approach to compensation appropriately aligns the interests of our non-employee directors and our stockholders in the future success of the Company, while assuring we do not provide excessive compensation.

Required Vote and Board Recommendation

        The board urges you to approve the Director Compensation Policy as it believes it to be in the best interests of the Company and its stockholders. If our stockholders do not approve the Director Compensation Policy at the Annual Meeting, the board will evaluate the best interests of the Company and decide the action to be taken with respect to such stockholder vote; however, for 2018, the board will not grant compensation in excess of any element of the compensation payable for 2018 set forth above.

        The affirmative vote of stockholders present in person or represented by proxy at the Annual Meeting representing a majority of the shares of common stock present in person or represented by proxy at the Annual Meeting, entitled to vote and voting on the proposal is required to approve the Director Compensation Policy. Abstentions and broker non-votes are not taken into account in determining the outcome of this vote.

        THE BOARD RECOMMENDS A VOTE "FOR" APPROVAL OF THE NON-EMPLOYEE DIRECTOR COMPENSATION POLICY, INCLUDING COMPENSATION AMOUNTS FOR 2018.

EXECUTIVE OFFICERS

        TESARO has seven executive officers: Mr. Moulder, our Chief Executive Officer; Dr. Hedley, our President and Chief Operating Officer; Timothy R. Pearson, our Executive Vice President and Chief Financial Officer; Grant C. Bogle, our Senior Vice President and Chief Commercial Officer; Joseph L. Farmer, our Senior Vice President, General Counsel and Secretary; Martin H. Huber, M.D., our Senior Vice President and Chief Medical Officer; and Orlando Oliveira, our Senior Vice President and General Manager, International. Information on Mr. Moulder and Dr. Hedley and their business experience is set forth above in "Proposal No. 1—Election of Directors." Information on Mr. Pearson, Mr. Bogle, Mr. Farmer, Dr. Huber, and Mr. Oliveira and their business experience is set forth below.

        Timothy R. Pearson (50) has served as Executive Vice President and Chief Financial Officer since May 2014. Prior to joining us, Mr. Pearson served as Chief Financial Officer, Executive Vice President and Treasurer of Catalyst Health Solutions, Inc., a publicly held pharmacy benefit manager, from August 2011 until Catalyst was acquired by SXC Health Solutions (now Catamaran Corporation) in July 2012. Prior to joining Catalyst, Mr. Pearson served as Chief Financial Officer and Executive Vice President of MedImmune, the global biologics business for AstraZeneca plc. Mr. Pearson, a Certified Public Accountant, holds dual B.S. degrees from the University of Delaware (in business administration) and the University of Maryland University College (in accounting), as well as an M.S. in Finance from Loyola University. Mr. Pearson serves on the board of directors of GlycoMimetics, Inc. (NASDAQ: GLYC) and RA Pharmaceuticals, Inc. (NASDAQ: RARX).

        Grant C. Bogle (60) has served as Senior Vice President and Chief Commercial Officer since July 2015. Prior to joining us, Mr. Bogle was Senior Vice President, Pharmaceutical and Biotech Solutions at McKesson Specialty Health, where he was part of the executive leadership team and led the informatics, health economics and outcomes research, reimbursement access and safety services, and U.S. Oncology Clinical Research business units. These business units were comprised of approximately 1,000 employees. Mr. Bogle was an employee of McKesson for eight years. Previously, he was Senior Vice President of Sales and Marketing for Millennium Pharmaceuticals, where he was responsible for the oncology product, VELCADE. Prior to joining Millennium, Mr. Bogle held senior sales and marketing roles at numerous other pharmaceutical companies. He holds an M.B.A. from Columbia University and a B.A. in economics from Dartmouth College.

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        Joseph L. Farmer (46) has served as Senior Vice President, General Counsel and Secretary since March 2015. From November 2012 until February 2015, Mr. Farmer served as Vice President, Chief Corporate Counsel and Assistant Secretary of Cubist Pharmaceuticals, Inc., prior to its sale to Merck & Co., Inc. Prior to joining Cubist, Mr. Farmer served as Vice President, General Counsel and Secretary of publicly-traded software company Pegasystems Inc. from June until November 2012. From February 2005 until June 2012, Mr. Farmer held management positions with increasing levels of responsibility at AMAG Pharmaceuticals, Inc., a publicly-traded specialty pharmaceutical company, including as its Chief Administrative Officer, General Counsel and Secretary. He received his B.A. in economics from Boston University and his J.D. from Boston College Law School.

        Martin H. Huber, M.D. (58) has served as Senior Vice President and Chief Medical Officer since September 2015. Prior to joining us, beginning in 2009, Dr. Huber served as Vice President, Oncology Clinical Research, at Merck Research Laboratories. Dr. Huber has over 20 years of leadership experience in the biopharmaceutical industry. Prior to Merck, he served in roles of increasing responsibility at Schering-Plough, Hoffmann-La Roche and Rhone-Poulenc Rorer, where he led teams in the areas of oncology clinical development, drug safety and pharmacovigilance. He previously served as an assistant professor of oncology at the University of Texas MD Anderson Cancer Center. Dr. Huber received his M.D. from Baylor College of Medicine.

        Orlando Oliveira (42) has served as Senior Vice President and General Manager, International since September 2015. Prior to joining us, Mr. Oliveira was Vice President, Europe and Intercontinental Operations at Cubist Pharmaceuticals, where he led a team of executives that managed operations in 19 countries across Europe, Canada and Australia and was responsible for all alliances within Cubist covering Japan, China, Latin America and the Middle East and North Africa regions. Previously, from 2001 through 2014, Mr. Oliveira held several positions of increasing responsibility at Amgen, Inc., including country leadership roles in Portugal and Mexico and international oncology marketing roles. He began his career in sales at Johnson and Johnson. He earned his pharmacy degree from the University of Coimbra, Portugal.

COMPENSATION OF EXECUTIVE OFFICERS

Compensation Discussion & Analysis

        This Compensation Discussion & Analysis addresses the principles underlying our policies and decisions with respect to the compensation of our executive officers who are named in the "Summary Compensation Table" below, or our "named executive officers," and material factors relevant to these policies and decisions. It should be read together with the related tables and disclosures that follow. Our named executive officers for the year ended December 31, 2017 were:

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Leon O. Moulder, Jr., our Chief Executive Officer;



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Mary Lynne Hedley, Ph.D., our President and Chief Operating Officer;



•

Timothy R. Pearson, our Executive Vice President and Chief Financial Officer;



•

Martin H. Huber, M.D., our Senior Vice President and Chief Medical Officer; and



•

Orlando Oliveira, our Senior Vice President and General Manager, International.

Compensation Philosophy and Objectives

        Our primary objectives with respect to the compensation of our named executive officers are to retain and motivate them because we believe they have experience and competencies that are critical to achievement of our business goals. This is consistent with the overall approach of our compensation system generally, which is to attract, retain and motivate employees (including our officers) who have

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relevant, critical skills and experience, and can make important contributions to the achievement of our business goals. We seek to achieve these objectives by:

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Establishing the components of our compensation packages at competitive levels.  For our named executive officers, this means using comparative market data as an integral element in setting compensation levels.



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Implementing annual variable incentive compensation that is tied to specific corporate goals. Our annual incentive program is focused on motivating our executives to achieve both company-wide and individual goals that are tied to our strategic plan.



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Using equity awards that vest over time and deliver greater value as our stock price increases. Using equity awards in order to align our named executive officers' interests with the interest of our stockholders in increasing long-term stockholder value.

        As the pie chart below indicates, nearly 90% of our Chief Executive Officer's target compensation is variable compensation tied to either future operational or stock-price performance of the Company. Similarly, well over 80% of the target compensation for each of our other named executive officers is tied to future performance of the Company.

Strong Compensation Practices

        Our compensation program features a number of practices designed to further align the interests of our named executive officers with those of our stockholders.

        Practices we employ:

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We pay for performance.  Compensation tied to Company performance comprises a significant part of an executive's total compensation, and long-term equity-linked compensation is the largest element of total compensation.



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We target pay competitively.  We seek to target pay to verifiable market data in order to ensure that we are both paying fairly and not overpaying our executives.



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We use an independent compensation consultant.  For 2017 compensation decisions, the compensation committee engaged Pearl Meyer & Partners, LLC ("Pearl Meyer") as an independent compensation consultant to advise the committee and help verify market and best practices.



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We have meaningful vesting periods.  Our equity awards generally have four-year ratable vesting from the date of grant.

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•

We have a recoupment policy.  Our incentive plans require repayment of awards in the event of an accounting restatement involving certain forms of misconduct.



•

We have director and executive officer stock ownership guidelines.  Each of our directors and Section 16 Officers is required to hold shares of our common stock with a value equal to at least (i) in the case of directors, three times the amount of the annual base retainer fee paid to directors, (ii) in the case of our CEO and President, five times the amount of his or her annual base salary, and (iii) in the case of our Section 16 Officers, one and a half times the amount of his or her annual base salary.

        Practices we do not employ:

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We do not offer single trigger change of control payments.  Our severance arrangements are "double trigger" and in the event of a change of control will only provide severance payments if there is a termination of employment.



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We do not provide for excessive perquisites.  We do not provide any perquisites to our named executive officers, other than limited amounts with respect to insurance payments.



•

We do not offer guaranteed bonuses.  The Company's annual incentive plan does not provide payment without achievement of performance goals, regardless of the reason for the failure to achieve performance goals.



•

We do not provide for tax gross-ups.  We do not provide any tax gross-ups to executives (other than customary payments in connection with relocation payments), including on any severance/change in control payments.



•

We do not permit hedging or pledging of our securities.  We prohibit our directors and officers from profiting from short-term speculative swings in the value of the Company's stock through "short sales," "put" and "call" options or other derivative securities, forward sale contracts and other hedging transactions. We also prohibit our directors and officers from pledging, borrowing against any account in which Company securities are held, or creating any other encumbrance with respect to securities of the Company.

Compensation Setting Process

        Determination of Compensation.    The compensation committee of our board of directors makes compensation decisions regarding our named executive officers, other than our Chief Executive Officer. For our Chief Executive Officer, the compensation committee makes formal recommendations to the independent members of the board of directors, who make the final compensation decisions for our Chief Executive Officer.

        When making decisions about compensation for the named executive officers other than Mr. Moulder, the compensation committee considers and gives substantial weight to the recommendations of Mr. Moulder and Dr. Hedley (to the extent the named executive officer reports to her) regarding their performance, and the committee's independent compensation consultant, as well as its industry experience and business judgment. The compensation committee and the board of directors evaluate the performance of Mr. Moulder and make determinations as to his compensation based on their assessment of his and the Company's performance and the recommendation of the independent compensation consultant.

        Independent Compensation Consultant.    For 2017 compensation decisions, the compensation committee engaged Pearl Meyer as an independent compensation consultant. Pearl Meyer provided analysis and recommendations to the compensation committee regarding:

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trends and emerging topics with respect to executive compensation;

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peer group selection for executive compensation benchmarking;



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compensation practices for our peer group;



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compensation programs and levels for executives and all of our associates; and



•

stock utilization and related metrics.

        When requested, Pearl Meyer consultants attended meetings of the compensation committee, including executive sessions in which executive compensation issues were discussed. Pearl Meyer reported to the compensation committee and not to management, although Pearl Meyer met with management for purposes of gathering information for its analyses and recommendations.

        In determining to engage Pearl Meyer, the compensation committee considered the independence of Pearl Meyer, taking into consideration relevant factors, including the absence of other services provided to the Company by Pearl Meyer, the amount of fees the Company paid to Pearl Meyer as a percentage of Pearl Meyer's total revenue, the policies and procedures of Pearl Meyer that are designed to prevent conflicts of interest, any business or personal relationship of the individual compensation advisors employed by Pearl Meyer with an executive officer of the Company, any business or personal relationship the individual compensation advisors employed by Pearl Meyer had with any member of the compensation committee, and any stock of the Company owned by Pearl Meyer or the individual compensation advisors employed by Pearl Meyer. The compensation committee has determined, based on its analysis in light of all relevant factors, including the factors listed above, that the work of Pearl Meyer and the individual compensation advisors employed by Pearl Meyer as compensation consultants to the compensation committee did not create any conflicts of interest, and that Pearl Meyer qualified as independent pursuant to the independence standards set forth in the NASDAQ listing standards promulgated pursuant to Section 10C of the Exchange Act.

        Comparative Framework.    As part of its consideration of executive officer compensation for 2017, the compensation committee used a comparative framework developed with the assistance of Pearl Meyer. This framework used information from proxy statements of the peer group of companies and from the 2016 Radford Global Life Sciences Survey data, which is assembled from publicly-traded biotechnology and life sciences companies, in order to develop a competitive market against which compensation can be measured.

        To develop the peer group of companies, the compensation committee, with assistance from Pearl Meyer, considered the market capitalization, size, revenues, stage of development, and other key business metrics of other biotechnology and biopharmaceutical companies relative to the Company. The selected peer group consisted of the following companies:

        Prior Votes on Executive Compensation.    In 2017, approximately 99% of the stockholder votes cast on the Company's non-binding proposal on executive compensation were voted in favor of the Company's executive compensation proposal, and the compensation committee considered this level of overwhelming support in setting 2018 compensation levels. The compensation committee of the board expects to take into account the outcome of future votes on executive compensation as it considers the Company's executive compensation program.

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Components of our Compensation Program

        The compensation program for our named executive officers consists of base salary, annual variable incentives under our short-term incentive ("STI") program and long-term incentives that are comprised of equity awards. Our named executive officers are also entitled to certain compensation upon termination of their employment. We believe these different forms of compensation provide appropriate incentives to achieve our business goals within the context of our overall philosophy for compensation.

        The compensation committee generally tries to establish compensation for our named executive officers so that base salary and short-term incentive target opportunities are at approximately the 50^th percentile of the competitive market composite and so that long-term incentive opportunities are at approximately the 75^th percentile of the competitive market composite. The compensation committee believes these targets are consistent with our philosophy discussed above of establishing compensation at competitive levels in order to attract and retain high performing executives, while focusing on opportunities to align our named executive officers' interests with the interest of our stockholders in increasing long-term stockholder value.

        Base Salary.    The base salary payable to each named executive officer is intended to provide a fixed component of compensation reflecting the executive's skill set, experience, roles and responsibilities.

        For 2017, the compensation committee and board of directors approved increasing the base salary for each of Mr. Moulder and Dr. Hedley to $660,000 and $610,000, respectively. The increases to Mr. Moulder's and Dr. Hedley's base salaries, 3.1% and 4.3%, respectively, were made, in part, in an effort to make them competitive with the base salaries of similarly-situated executives at our peer companies, as well as to provide customary market merit-based annual base salary increases and to recognize their performance.

        Mr. Pearson's base salary was increased for 2017 to $420,000, reflecting a market merit-based increase of approximately 4.4% based on his performance. Dr. Huber's base salary was increased to $460,000, an 8.9% increase over his 2016 base salary, reflecting both the high level of his performance and an effort to make his base salary competitive with similarly-situated chief medical officers at our peer companies. Mr. Oliveira's base salary was increased to $457,000, a 17% increase over his 2016 base salary, reflecting both the high level of his performance and an effort to make his base salary competitive with similarly-situated international general managers based on international survey data. The foregoing increases were each made, in part, to make each executive's salary competitive with approximately the 50^th percentile of base salaries of similarly situated executives at our peer companies.

Short-term Incentive Program.

        General.    Our STI program is intended to provide a cash incentive to our named executive officers for achieving both company-wide and individual goals approved at the beginning of each year by our compensation committee and board of directors. We believe that having an annual STI program provides an important and customary retention tool and motivates our executives to achieve the specific goals that are a part of the program.

        Relative Weighting Between Company-wide and Individual Goals.    For 2017, the company-wide goals and individual goals for our named executive officers were established by the compensation committee and approved by our board of directors. The compensation committee and the board of directors

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determined that for 2017 the STI program would weight company-wide goals and individual goals as set forth in the chart below for each of our named executive officers:

        The relative weighting between the company-wide goals and the individual goals reflects our belief that if the primary focus of our named executive officers is the achievement of company-wide goals, then we will increase the likelihood of achieving our strategic plan.

        Target Payout.    The STI program is structured so that achievement of the company-wide goals and the individual goals at a level of 100% would result in the named executive officer receiving an STI target payment in an amount equal to a specified percentage of his or her base salary. For each named executive officer, a 100% achievement under the STI program would result in a target payment expressed as a percentage of base salary, which was equal to 70% for Mr. Moulder, 65% for Dr. Hedley, and 50% for each of the other named executive officers. The target STI percentage for each of our named executive offices is intended to approximate the 50^th percentile of the percentage STI opportunity available to similarly situated executives at our peer companies so that, when combined with such executive's base salary, the total potential cash compensation of each officer is at approximately the 50^th percentile of his or her peers. The STI program for 2017 was also structured so that each named executive officer could achieve up to 150% of the target award with respect to the achievement of the company-wide goals, and up to 120% with respect to achievement of the individual goals, in each case for exceptional performance. The compensation committee believes that payment of more than 100% of a target award with respect to the achievement of company-wide or individual goals is an appropriate reward for exceptional performance, but it also believes that there should be an upper limit on the opportunities under the STI program.

        Company-wide Goals.    For 2017, we had four company-wide goals. The four goals were based on our operating plan and long-term strategy. The compensation committee and the board of directors agreed that each of our company-wide goals should be weighted based on their subjective judgment regarding the relative importance of each of these goals. The compensation committee believes it established target goals that were achievable with an appropriate amount of dedication and hard work and, therefore, it was more likely than not that each executive officer would earn a payment under the STI program, but not necessarily the target award under the STI program, which is consistent with our compensation philosophy. Our compensation committee believes that at the time the objectives were set, there would be a substantial degree of difficulty in achieving the objectives at the target 100% level and a much greater degree of difficulty in achieving them at the stretch level.

        In early 2018, our compensation committee reviewed our progress on the company-wide goals for 2017 and concluded that the company-wide goals had been achieved at an 88% level. For each of the named executive officers, this meant that they earned 88% of the company-wide goals portion of their STI target payment, or 88% of the total STI target payment for Mr. Moulder, 79.2% of the total STI target payment for Dr. Hedley, and 70.4% of the total STI target payment for the other named executive officers.

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        The following table reflects the company-wide goals for 2017, the respective weighting and the level of achievement for each goal, as determined by the board of directors, based on the recommendation of the compensation committee:

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        Individual Goals.    At the beginning of 2017, the compensation committee established individual goals for each of our named executive officers who were then serving, other than our Chief Executive Officer, whose performance is evaluated 100% based upon achievement of the company-wide goals. The rationale behind assigning individual goals to each of our other named executive officers is that each of them is responsible for activities within their respective job functions that support achieving company-wide goals and the Company's strategic plan. We believe that it is important that these individual goals be achieved and incentivized. Nevertheless, as demonstrated by the relative weighting between the company-wide goals and the individual goals for each of our named executive officers, we believe that achievement of the company-wide goals has a more direct and immediate impact on the creation of stockholder value than the achievement of the individual goals.

        We assigned each of the named executive officers, other than our Chief Executive Officer, between three and five individual goals. Each of those individual goals was then weighted to reflect the decision of our compensation committee, based on the recommendation of our Chief Executive Officer and/or our President and Chief Operating Officer (to the extent the named executive officer reports to her), as to the relative importance of each goal to the officer's job function and the contribution that successfully performing the goal would make to our company-wide goals and strategic plan. If the officer accomplished all of his or her individual goals at his or her expected performance level, then the officer would receive 100% of the target STI payment with respect to the officer's individual goals. For Dr. Hedley, this would equate to 10% of her total STI target payment. For Mr. Pearson, Dr. Huber, and Mr. Oliveira this would equate to 20% of each of their respective total STI target payments. For 2017, the officers also had the opportunity to achieve at a level of up to 120% of the target STI payment related to the individual goals.

        For the named executive officers other than Mr. Moulder, our compensation committee determines the level of achievement of their respective individual goals. This determination is made following consultation with Mr. Moulder and is based in large part on his recommendation and that of Dr. Hedley, to the extent a named executive officer reports to her.

        The following paragraphs describe for each of our named executive officers their individual goals, the relative weighting of each of those individual goals, the level of achievement by the executive officer for each individual goal, and the percentage STI payment arising from the achievement of the individual goal.

        Leon O. Moulder, Jr., Chief Executive Officer.    Mr. Moulder's STI payment is based 100% upon the achievement of the Company-wide annual goals. Accordingly, for 2017, Mr. Moulder earned 88% of his total target STI payment.

        Mary Lynne Hedley, Ph.D., President and Chief Operating Officer.    Dr. Hedley was assigned goals related to (1) providing overall leadership for the Company (30% weighting), (2) ensuring organizational alignment and scalability to develop, operationalize and support the Company's long-range strategic plan (25% weighting), (3) the development and execution of our business development strategy and the maintenance of successful alliances with key partners (25% weighting), and (4) contributing to the investor relations goals of the Company (20% weighting). Based on the achievement of her individual goals, particularly her exceptional leadership in developing and executing our long range plan and business development strategy, the compensation committee determined that Dr. Hedley achieved her individual goals at the 100% level. Accordingly, for 2017, Dr. Hedley earned 100% of the 10% portion of the total STI target payment that was attributed to the achievement of her individual performance goals.

        Timothy R. Pearson, Executive Vice President and Chief Financial Officer.    Mr. Pearson was assigned goals related to (1) continuing to build an organizational structure for the finance and information technology functions to support the Company's growth (30% weighting), (2) achieving financial goals

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related to capital raising activities (20% weighting), (3) driving overall corporate strategy development in conjunction with the CEO and President (30% weighting), (4) enhancing the Company's financial planning and analytic capabilities (10% weighting), and (5) leadership of certain governance and compliance processes (10% weighting). Based on the achievement of his individual goals, particularly his exceptional leadership with respect to the execution of the Company's debt facility and the implementation of the Company's ERP system, the compensation committee determined that Mr. Pearson achieved his individual goals at the 105% level. Accordingly, for 2017, Mr. Pearson earned 105% of the 20% portion of the total STI target payment that was attributed to the achievement of his individual performance goals.

        Martin H. Huber Jr., M.D., Senior Vice President and Chief Medical Officer.    Dr. Huber was assigned goals related to (1) building a high-quality and sustainable global research and development organization (25% weighting), (2) the achievement of the various development goals established by the Company's various core teams with respect to the Company's ongoing development programs (20% weighting), (3) reporting initial data from the Company's niraparib breast cancer clinical trial (10% weighting), (4) developing a high-quality and effective global medical affairs function (20% weighting), and (5) developing and improving the performance of the Company's global clinical and study sub-teams (25% weighting). Based on the achievement of each of his individual goals, including his exceptional overall leadership of the Company's research and development function, the compensation committee determined that Dr. Huber achieved his individual goals at the 110% level. Accordingly, for 2017, Dr. Huber earned 110% of the 20% portion of the total STI target payment that was attributed to the achievement of his individual performance goals.

        Orlando Oliveira, Senior Vice President and General Manager, International.    Mr. Oliveira was assigned goals related to (1) obtaining regulatory approvals for ZEJULA and oral VARUBY in a timely manner and achieving sales objectives related to each product (40% weighting), (2) building and retaining a high quality international organization consistent with the Company's culture and values (30% weighting), and (3) ensuring timely execution of all pre-launch activities, including deployment of the Company's Early Access Program and the development of the Company's pricing strategy in Europe (30% weighting). Based on the achievement of each of his individual goals, including his exceptional leadership with respect to the ZEJULA and VARUBY product launches in Europe, the compensation committee determined that Mr. Oliveira achieved his individual goals at the 115% level. Accordingly, for 2017, Mr. Oliveira earned 115% of the 20% portion of the total STI target payment that was attributed to the achievement of his individual performance goals.

        Overall STI Program Payments for 2017.    The following table sets forth for each of our named executive officers, their target STI payment, including as a percentage of base salary, the percentages of the STI payment attributable to company-wide and individual goals, the level of performance achieved by each named executive officer with respect to both the company-wide and individual goals, and the total STI payment to each named executive officer as a result of his or her participation in the STI program for 2017. Where appropriate, we have included this information both as a percentage and as a dollar amount.

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        Long-term Incentive Program.    Our use of equity awards is intended to align our named executive officers' interests with the interests of our stockholders by providing an incentive to our named executive officers to increase long-term stockholder value. Furthermore, we believe that in the biopharmaceutical industry, equity awards are a primary motivator to retain executives. We determine the size and frequency of awards based on numerous factors, including the executive's skills and experience, the executive's responsibilities, internal equity and the approach to setting compensation described under "—Determination of Compensation" above.

        In February 2017, the compensation committee and the board of directors authorized grants of a mix of stock options and RSUs to each of Mr. Moulder, Dr. Hedley, Mr. Pearson, Dr. Huber and Mr. Oliveira as of March 1, 2017. The compensation committee first began to incorporate the use of RSUs into our equity award program to take into account the relative growth of the Company as we transitioned to a more mature commercial-stage biopharmaceutical company. The compensation committee believes that RSUs are an effective method of both rewarding and incentivizing our named executive officers in a manner less dilutive than stock options, while also continuing to align their interests with those of our stockholders by creating a mechanism to encourage executives to take a larger ownership stake in the Company. The compensation committee also believes it is important to continue to utilize stock options because it believes that stock options are very effective tools for motivating executives to increase long-term value and align our executives' interests with those of our stockholders.

        To determine the exact number of equity awards to grant to each executive, the compensation committee determined an approximate dollar value delivered to similarly-situated executives at our peer group companies, in each case targeted at approximately the 75^th percentile of the competitive market composite. Taking into account the rationale discussed above for the use of options and RSUs, the compensation committee determined to split the grant values relatively equally between stock options and RSUs. The specific number of options that was awarded to each of Mr. Moulder, Dr. Hedley, Mr. Pearson, Dr. Huber and Mr. Oliveira was determined using a Black-Scholes option pricing model, and the specific number of RSUs was determined using the then-current fair market value of our common stock.

        All of the stock options issued to the named executive officers in 2017 vest in 48 equal installments on each monthly anniversary of the grant date. The RSUs granted as part of the annual grant to executives in 2017 vest in equal installments on each of the first four annual anniversaries of the grant date.

Offer Letters and Employment Letter Agreements

        In May 2010, in connection with our Series A preferred stock financing, we entered into offer letters with Mr. Moulder and Dr. Hedley that provided for compensation arrangements appropriate for executives at what was then a small, private company. In June 2012, these agreements were amended and restated in anticipation of our initial public offering in order to form a part of a competitive compensation package for a publicly-traded company and to keep Mr. Moulder and Dr. Hedley focused on our business goals and objectives. In February 2017, in connection with a periodic review of the terms of the employment letter agreements by the compensation committee to ensure that the terms of our executives' employment arrangements remain competitive with similarly-situated executives in the peer group, Mr. Moulder and Dr. Hedley each entered into an amended and restated employment letter agreement with the Company.

        We entered into offer letters when each of Mr. Pearson, Dr. Huber and Mr. Oliveira joined the Company in 2014, 2015 and 2015, respectively. Shortly after Mr. Oliveira joined the company in 2015, his offer letter was superseded by a new employment agreement. In February 2017, in connection with the periodic review discussed above, Mr. Pearson and Dr. Huber each entered into an amended and

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restated employment letter agreement with the Company. In general, the employment letter agreements with Mr. Pearson and Dr. Huber are consistent with the amended and restated employment letter agreements with Mr. Moulder and Dr. Hedley. It was determined during the periodic review not to amend Mr. Oliveira's employment agreement in light of the fact that his agreement already contained certain benefits comparable to those contained in the amended and restated employment letter agreements of other executive officers.

        See "—Employment Letter Agreements" below for further details on the specific terms of the various employment letter agreements with each of our named executive officers and of Mr. Oliveira's employment agreement.

Payments on Termination

        Pursuant to their 2017 amended and restated employment letter agreements, and in the case of Mr. Oliveira, his 2015 employment agreement, each of our named executive officers is entitled to specified benefits in the event of the termination of their employment under specified circumstances, including termination following a change of control of the Company. The terms of these arrangements are more fully described below under "—Employment Letter Agreements" and "—Potential Payments Upon a Termination or Change in Control." We believe these protections are appropriate and standard for the senior executives of a biopharmaceutical company such as the Company, in light of the high level of acquisition activity in our industry. We believe that providing benefits in the event of a change of control of the Company allows our named executive officers to focus their attention on building our business rather than on the personal implications of a transaction.

Federal Tax Considerations under Section 162(m)

        Section 162(m) of the Code generally disallows a federal income tax deduction to any publicly traded corporation for any remuneration in excess of $1.0 million of compensation paid to specified executive officers in a calendar year. The Tax Cuts and Jobs Act of 2017 eliminated certain exceptions to the $1.0 million deduction limit for qualified performance-based compensation, except with respect to certain agreements in effect on November 2, 2017 (the "162(m) Grandfather"). Historically, where the compensation committee determined it was reasonably practicable and consistent with our overall compensation program objectives, it sought to structure the equity incentives component of our executive compensation program to comply with the exemptions in Section 162(m). To the extent that it is practicable and consistent with our overall compensation program objectives, we intend to administer outstanding arrangements subject to the 162(m) Grandfather to preserve potential deductions that may be available thereunder. However, our board of directors or compensation committee may, in their judgment, authorize new compensation arrangements that will not be fully deductible under Section 162(m) in situations where they believe that such arrangements are appropriate.

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Summary Compensation Table

        The following table presents summary information regarding the total compensation awarded to, earned by, or paid to our named executive officers for services rendered to us for the year ended December 31, 2017 and, where applicable, the prior years.

Narrative Disclosure Relating to Summary Compensation Table

        For an explanation of the amount of salary, bonus, stock and option awards and other compensation paid to our named executive officers, please see "—Compensation Discussion & Analysis—Components of our Compensation Program," and the disclosure provided in "—Summary Compensation Table" above.

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Grants of Plan-Based Awards

        The following table provides information regarding grants of plan-based awards to each of our named executive officers during 2017.

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Outstanding Equity Awards at Fiscal Year-End

        The following table provides information regarding equity awards held by each of our named executive officers that were outstanding as of December 31, 2017.