Check the appropriate box:

You are cordially invited to attend the 20212022 Annual Meeting of Stockholders (“Annual Meeting”) of Allogene Therapeutics, Inc., a Delaware corporation (the “Company”). The meeting will be held on June 10, 202115, 2022 at 10:008:30 a.m., Eastern Time. This year’s Annual Meeting will be a completely virtual meeting of stockholders. You can attend the Annual Meeting by visiting www.virtualshareholdermeeting.com/ALLO2021ALLO2022 where you will be able to listen to the meeting live, submit questions and vote online. We are holding the Annual Meeting for the following purposes, as more fully described in the accompanying proxy statement:

Pursuant to rules adopted by the Securities and Exchange Commission (the “SEC”), we have elected to provide access to our proxy materials over the internet. Accordingly, we have sent you a Notice of Internet Availability of Proxy Materials (the “Notice”) because the Board of Directors (sometimes referred to as the “Board”) of Allogene Therapeutics, Inc. (sometimes referred to as “we,” “us,” “our,” the “Company” or “Allogene”) is soliciting your proxy to vote at the 20212022 Annual Meeting of Stockholders (“Annual Meeting”), including at any adjournments or postponements of the meeting. The Annual Meeting will be held virtually on June 10, 202115, 2022 at 10:008:30 a.m., Eastern Time. You can attend the Annual Meeting by visiting www.virtualshareholdermeeting.com/ALLO2021,ALLO2022, where you will be able to listen to the meeting live, submit questions and vote online. All stockholders will have the ability to access the proxy materials on the website referred to in the Notice or request to receive a printed set of the proxy materials. Instructions on how to access the proxy materials over the internet or to request a printed copy may be found in the Notice.

We may send you a proxy card, along with a second Notice, on or after May 3, 2021.7, 2022.

This year we have implemented a virtual format for our Annual Meeting, which will be conducted via live audio webcast and online stockholder tools. We believe a virtual format helps to facilitate stockholder attendance and participation by enabling stockholders to participate fully, and equally, from any location around the world at no cost (other than any costs associated with your Internet access, such as usage charges from Internet access providers and telephone companies). A virtual Annual Meeting makes it possible for more stockholders (regardless of size, resources or physical location) to have direct access to information more quickly, while saving the Company and our stockholders time and money. We also believe that the online tools we have selected will increase stockholder communication. For example, the virtual format allows stockholders to communicate with us in advance of, and during, the Annual Meeting so they can ask questions of our board of directors or management. During the Annual Meeting, we may answer questions submitted during the Annual Meeting and address those asked in advance, to the extent relevant to the business of the Annual Meeting, as time permits. We do not intend to post questions received during the Annual Meeting on our website.

You will be able to attend the Annual Meeting online, submit your questions during the meeting and vote your shares electronically at the meeting by visiting www.virtualshareholdermeeting.com/ALLO2021.ALLO2022. To participate in the Annual Meeting, you will need the control number included on your Notice or proxy card. The Annual Meeting webcast will begin promptly at 10:008:30 a.m. Eastern Time on June 10, 2021.15, 2022. We encourage you to access the meeting prior to the start time. Online check-in will begin at 9:458:15 a.m. Eastern Time, and you should allow ample time for the check-in procedures.

Only stockholders of record at the close of business on April 12, 202118, 2022 will be entitled to vote at the Annual Meeting. On this record date, there were 141,485,913143,598,970 shares of common stock outstanding and entitled to vote. A list of our stockholders of record will be open for examination by any stockholder beginning ten days prior to the Annual Meeting at our headquarters located at 210 East Grand Avenue, South San Francisco, California 94080. If you would like to view the list, please contact our Corporate Secretary to schedule an appointment by calling (650) 457-2700 or writing to him at the address above. In addition, the list will be available for inspection by stockholders on the virtual meeting website during the Annual Meeting.

If on April 12, 2021,18, 2022, your shares were registered directly in your name with Allogene’s transfer agent, American Stock Transfer & Trust Company, LLC, then you are a stockholder of record. As a stockholder of record, you may vote live online at the meeting or vote by proxy. Whether or not you plan to attend the meeting, we urge you to fill out and return the proxy card that may be mailed to you or vote by proxy over the telephone or on the internet as instructed below to ensure your vote is counted.

If on April 12, 202118, 2022 your shares were held, not in your name, but rather in an account at a brokerage firm, bank, dealer or other similar organization, then you are the beneficial owner of shares held in “street name” and the Notice is being forwarded to you by that organization. The organization holding your account is considered to be the stockholder of record for purposes of voting at the Annual Meeting. As a beneficial owner, you have the right to direct your broker or other agent regarding how to vote the shares in your account. You are also invited to attend the Annual Meeting. However, since you are not the stockholder of record, you may not vote your shares live at the meeting unless you request and obtain a valid proxy from your broker or other agent.

There are threesix matters scheduled for a vote:

The Board of Directors knows of no other matters that will be presented for consideration at the Annual Meeting. If any other matters are properly brought before the meeting, it is the intention of the persons named in the accompanying proxy to vote on those matters in accordance with their best judgment.

You may either vote “For” all the nominees to the Board of Directors or you may “Withhold” your vote for any nominee you specify. With regard to your advisory vote on how frequently we should solicit stockholder advisory approval of executive compensation, you may vote for any one of the following: one year, two years or three years, or you may abstain from voting on that matter. For each of the other matters to be voted on, you may vote “For” or “Against” or abstain from voting.

If you are a stockholder of record, you may vote live online at the Annual Meeting, vote by proxy over the telephone, vote by proxy through the internet or vote by proxy using a proxy card that you may request or that we may elect to deliver at a later time. Whether or not you plan to attend the meeting, we urge you to vote by proxy to ensure your vote is counted. You may still attend the meeting and vote live online even if you have already voted by proxy.

If you are a beneficial owner of shares registered in the name of your broker, bank, or other agent, you should have received a Notice containing voting instructions from that organization rather than from Allogene. Simply follow the voting instructions in the Notice to ensure that your vote is counted. To vote live online at the Annual Meeting, you must obtain a valid proxy from your broker, bank or other agent. Follow the instructions from your broker or bank included with these proxy materials, or contact your broker or bank to request a proxy form.

On each matter to be voted upon, you have one vote for each share of common stock you owned as of the close of business on April 12, 2021.18, 2022.

If you are a stockholder of record and do not vote by completing your proxy card, by telephone, through the internet or live online at the Annual Meeting, your shares will not be voted.

If you are a beneficial owner and do not instruct your broker, bank, or other agent how to vote your shares, the question of whether your broker or nominee will still be able to vote your shares depends on whether the New York Stock Exchange (“NYSE”) deems the particular proposal to be a “routine” matter. Brokers and nominees can use their discretion to vote “uninstructed” shares with respect to matters that are considered to be “routine,” but not with respect to “non-routine” matters. Under the rules and interpretations of the NYSE, “non-routine” matters are matters that may substantially affect the rights or privileges of stockholders, such as mergers, stockholder proposals, elections of directors (even if not contested), executive compensation (including any advisory stockholder votes on executive compensation and on the frequency of stockholder votes on executive compensation), and certain corporate governance proposals, even if management-supported. Accordingly, your broker or nominee may not vote your shares on Proposals 1, 2 or 24 without your instructions, but may vote your shares on ProposalProposals 3, 5 and 6 even in the absence of your instruction.

We will pay for the entire cost of soliciting proxies. In addition to these proxy materials, our directors and employees may also solicit proxies in person, by telephone, or by other means of communication. Directors and employees will not be paid any additional

If you receive more than one Notice, your shares may be registered in more than one name or in different accounts. Please follow the voting instructions on the Notices to ensure that all of your shares are voted.

Yes. You can revoke your proxy at any time before the final vote at the meeting. If you are the record holder of your shares, you may revoke your proxy in any one of the following ways:

If your shares are held by your broker or bank as a nominee or agent, you should follow the instructions provided by your broker or bank.

To be considered for inclusion in next year’s proxy materials, your proposal must be submitted in writing by December 24, 2021,28, 2022, to Attn: Secretary, 210 East Grand Avenue, South San Francisco, California 94080. If you wish to submit a proposal (including a director nomination) at the meeting that is not to be included in next year’s proxy materials, you must do so between February 10, 202215, 2023 and March 12, 2022.17, 2023. You are also advised to review the Company’s Bylaws, which contain additional requirements relating to advance notice of stockholder proposals and director nominations. In addition to satisfying the foregoing requirements under the Company’s Bylaws, to comply with the universal proxy rules (once effective), stockholders who intend to solicit proxies in support of director nominees other than our Board’s nominees must provide notice that sets forth any additional information required by Rule 14a-19 promulgated under the Securities Exchange Act of 1934, as amended, no later than April 16, 2023.

Set forth below is biographical information for each of our executive officers other than Dr. Chang, whose biographical information is set forth above

As required under the Nasdaq Stock Market (“Nasdaq”) listing standards, a majority of the members of a listed company’s board of directors must qualify as “independent,” as affirmatively determined by its board of directors. The Board consults with the Company’s counsel to ensure that the Board’s determinations are consistent with relevant securities and other laws and regulations regarding the definition of “independent,” including those set forth in pertinent listing standards of Nasdaq, as in effect from time to time.

Our Board is currently chaired by Dr. Belldegrun, who has authority, among other things, to call and preside over Board meetings, to set meeting agendas and to determine materials to be distributed to the Board. Accordingly, the Executive Chair has substantial ability to shape the work of the Board. We believe that separation of the positions of Executive Chair and Chief Executive Officer reinforces the independence of the Board in its oversight of our business and affairs. In addition, we have a separate chair for each committee of

our Board. The chair of each committee is expected to report periodically to our Board on the activities of their committee in fulfilling their responsibilities as detailed in their respective charters or specify any shortcomings should that be the case.

One of the key functions of our Board of Directors is informed oversight of our risk management process. The Board does not have a standing risk management committee, but rather administers this oversight function directly through the Board of Directors as a whole, as well as through the Audit Committee. The Audit Committee receives reports from management periodically regarding our assessment of risks. In addition, the Audit Committee reports regularly to our Board of Directors, which also considers our risk profile. The Audit Committee and our Board of Directors focus on the most significant risks we face and our general risk management strategies. For instance, the Audit Committee reviews cybersecurity risk, as part of its review of our cybersecurity framework, measures, tools, and compliance, on at least an annual basis. While our Board of Directors oversees our risk management, management is responsible for day-to-day risk management processes. Our Board of Directors expects management to consider risk and risk management in each business decision, to proactively develop and monitor risk management strategies and processes for day-to-day activities and to effectively implement risk management strategies adopted by the Audit Committee and our Board of Directors. We believe this division of responsibilities is the most effective approach for addressing the risks we face and that our Board of Directors’ leadership structure, which also emphasizes the independence of our Board of Directors in its oversight of its business and affairs, supports this approach.

The Board maintains an Audit Committee, a Compensation Committee, a Nominating and Corporate Governance Committee and International and Business Development Oversight Committee. The following table provides membership and meeting information for 20202021 for each of the foregoing Board committees:

The Audit Committee of the Board of Directors was established by the Board in accordance with Section 3(a)(58)(A) of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), to oversee the Company’s corporate accounting and financial reporting processes and audits of its financial statements. For this purpose, the Audit Committee performs several functions, including, among other things:

The Audit Committee has reviewed and discussed the audited financial statements for the fiscal year ended December 31, 20202021 with management of the Company. The Audit Committee has discussed with the independent registered public accounting firm the matters required to be discussed by the applicable requirements of the Public Company Accounting Oversight Board (“PCAOB”) and the SEC. The Audit Committee has also received the written disclosures and the letter from the independent registered public accounting firm required by applicable requirements of the PCAOB regarding the independent accountants’ communications with the Audit Committee concerning independence, and has discussed with the independent registered public accounting firm the accounting firm’s independence. Based on the foregoing, the Audit Committee recommended to the Board of Directors that the audited financial statements be included in the Company’s Annual Report on Form 10-K for the fiscal year ended December 31, 2020.

The Compensation Committee is composed of three directors: Mr. Bonderman, Mr. DeYoung and Dr. Humer and Mr. DeYoung.Humer. Mr. Bonderman serves as the chair of ourthe Compensation Committee. All members of the Compensation Committee are independent (as independence is currently defined in Rule 5605(d)(2) of the Nasdaq listing standards). The Board has adopted a written Compensation Committee charter that is available to stockholders on the Company’s website at www.allogene.com.

Typically, the Compensation Committee meets at least quarterly and with greater frequency if necessary. The agenda for each meeting is usually developed by the Chair of the Compensation Committee, in consultation with the Executive Chair, Chief Executive Officer, General Counsel, Secretary and Compensia, Inc. (“Compensia”), the Compensation Committee’s independent compensation consultant. The Compensation Committee meets regularly in executive session. However, from time to time, various members of management and other employees as well as outside advisors or consultants may be invited by the Compensation Committee to make presentations, to provide financial or other background information or advice or to otherwise participate in Compensation Committee meetings. The Chief Executive Officer may not participate in, or be present during, any deliberations or determinations of the Compensation Committee regarding his compensation or individual performance objectives. The charter of the Compensation Committee grants the Compensation Committee full access to all books, records, facilities and personnel of the Company. In addition, under the charter, the Compensation Committee has the authority to obtain, at the expense of the Company, advice and assistance from compensation consultants and internal and external legal, accounting or other advisors and other external resources that the Compensation Committee considers necessary or appropriate in the performance of its duties. The Compensation Committee has direct responsibility for the oversight of the work of any consultants or advisers engaged for the purpose of advising the Committee. In particular, the Compensation Committee has the sole authority to retain, in its sole discretion, compensation consultants to assist in its evaluation of executive and director compensation, including the authority to approve the consultant’s reasonable fees and other retention terms. Under the charter, the Compensation Committee may select, or receive advice from, a compensation consultant, legal counsel or other adviser to the Compensation Committee, other than in-house legal counsel and certain other types of advisers, only after taking into consideration six factors, prescribed by the SEC and Nasdaq, that bear upon the adviser’s independence; however, there is no requirement that any adviser be independent.

The Nominating and Corporate Governance Committee of the Board of Directors is responsible for:

Our International and Business Development Oversight Committee consists of Dr. Humer, as chair, and Mr. DeYoung, Mr. Kazam and Mr. Kazam.Dr. Sato. The purpose of the International and Business Development Oversight Committee is to assist our Board of Directors in fulfilling our Board of Directors' responsibilities to (1) oversee our international and business development strategic planning, and (2) review and evaluate any of our specific strategic initiatives, including the risks and opportunities relating to such initiatives. The International and Business Development Oversight Committee charter can be found on our website at www.allogene.com.

The Company’s Board has adopted a formal process by which stockholders may communicate with the Board or any of its directors. Stockholders who wish to communicate with the Board may do so by sending written communications addressed to: Attn: Secretary, 210 East Grand Avenue, South San Francisco, California 94080. These communications will be reviewed by the Secretary, who will determine whether the communication is appropriate for presentation to the Board or the relevant director. The purpose of this screening is to allow the Board to avoid having to consider irrelevant or inappropriate communications (such as advertisements, solicitations and hostile communications).

The Company has adopted the Code of Business Conduct and Ethics that applies to all officers, directors and employees. The Code of Business Conduct and Ethics is available on the Company’s website at www.allogene.com. If the Company makes any substantive amendments to the Code of Business Conduct and Ethics or grants any waiver from a provision of the Code to any executive officer or director, the Company will promptly disclose the nature of the amendment or waiver on its website.

The following table represents aggregate fees billed to the Company for the fiscal years ended December 31, 20192020 and December 31, 20202021 by Ernst & Young LLP, the Company’s principal accountant.

Pursuant to its charter, the Audit Committee must review and approve, in advance, the scope and plans for the audits and the audit fees and approve in advance (or, where permitted under the rules and regulations of the SEC, subsequently) all non-audit services to be performed by the independent registered public accounting firm that are not otherwise prohibited by law and any associated fees. The Audit Committee may delegate to one or more members of the committee the authority to pre-approve audit and permissible non-audit services, as long as this pre-approval is presented to the full committee at scheduled meetings.

This Compensation Discussion and Analysis discusses the compensation philosophy, policies and principles underlying our executive compensation decisions for 2020.2021. It provides qualitative information on the factors relevant to these decisions and the manner in which compensation is awarded to our named executive officers (our “Named Executive Officers”) for the fiscal year ended December 31, 2020,2021, which consist of our principal executive officer, principal financial officer and our remaining three executive officers during 2020.2021. Our Named Executive Officers for 20202021 were:

Our executive compensation program is intended to meet five principal objectives:

We seek to foster a performance-oriented culture, where individual performance is aligned with organizational objectives. To achieve this, we evaluate and reward our executive officers based on their contributions to the achievement of annual goals and objectives set early in the year. Performance is reviewed at least annually through processes discussed further below, with a focus on our research, clinical, regulatory, financial and operational performance, and in view of economic and financial conditions affecting the performance period. In addition, the Compensation Committee and our Board considered the positive results of the shareholder advisory vote on executive compensation held in 2021, where 69% of shareholders voted in favor of, and concluded our approach to compensation for named executive officers was appropriate.

OurThe Compensation Committee reviews and approves our executive compensation philosophy, objectives and methods, evaluates our performance and the performance of our executive officers, and either approves executive compensation or makes recommendations for ratification by our Board members. Please see “Information Regarding Committees of our Board of Directors—Compensation Committee—Compensation Committee Processes and Procedures” for additional information.

In making compensation decisions, ourthe Compensation Committee considers the recommendations of our Chief Executive Officer, with input from our Executive Chair, General Counsel and Secretary. Our Chief Executive Officer, Dr. Chang, makes recommendations to ourthe Compensation Committee with respect to our executive officers, but is not present and does not participate in the deliberations or determination of his own compensation. OurThe Compensation Committee may review and approve the corporate objectives and goals pursuant to the powers delegated under its charter. Dr. Chang annually leads the development of our corporate objectives and goals, which are typically reviewed and approved by the Compensation Committee and then our Board of Directors.Board. Dr. Chang provided the Company’sour business and operations perspective for ourthe Compensation Committee’s final review of progress made on the goals set for 2020.2021. Other than as described above, no other executive officers participate in the determination or recommendation of the amount or form of executive officer compensation.

OurThe Compensation Committee is authorized to engage a compensation consultant or other advisors to review our executive officers’ compensation, including preparing an analysis against the compensation of executive officers at comparable companies, to ensure that our compensation is market competitive, with the goal of retaining and adequately motivating our senior management. During 2020, our2021, the Compensation Committee engaged Compensia to make recommendations for updating our compensation peer group, and to review and make recommendations regarding our equity plan and executive and director compensation for 2020.2021. Compensia was invited to attend a Compensation Committee meetingmeetings where they presented and discussed their analysis and findings. For 2020,2021, with the assistance of Compensia, ourthe Compensation Committee updated our compensation peer group, described below in the section entitled “Peer Companies and Market Compensation Data.”

When making compensation decisions, ourthe Compensation Committee reviews the compensation of similarly-situated executive officers at companies that we consider to be our peers, taking into consideration the experience, position and functional role, level of responsibility and uniqueness of applicable skills of both our executive officers and those of our peers, and the demand and competitiveness for attracting and retaining an individual with each executive officer’s specific expertise and experience in the biotechnology industry. While this analysis is helpful in determining market-competitive compensation for senior management, leading to better attraction and retention of top-quality executive officers, it is only one factor in determining our executive officers’ compensation, and ourthe Compensation Committee exercises its judgment in determining the nature and extent of its use.

The components of our executive compensation program in 20202021 were as follows:

The base salaries of our executive officers are designed to compensate them for day-to-day services rendered during the fiscal year. Appropriate base salaries are used to recognize the experience, skills, knowledge and responsibilities required of each executive officer and to allow us to attract and retain individuals capable of leading us to achieve our business goals in competitive market conditions.

Our Named Executive Officers are eligible to receive annual performance-based cash bonuses, which are designed to provide appropriate incentives to our executive officers to achieve pre-established annual corporate goals and to reward them for individual performance towards these goals. The annual performance-based cash bonus each current Named Executive Officer is eligible to receive is generally based on the extent to which we achieve the corporate goals that theour Board establishes each year. At the end of the year, theour Board and the Compensation Committee review our performance and approve the extent to which we achieved each of these annual corporate goals. Generally, theour Board and the Compensation Committee, as applicable, will assess each Named Executive Officer’s individual contributions towards reaching our annual corporate goals but does not typically establish specific individual goals for our Named Executive Officers.

We provide long-term incentive compensation to our executive officers through the grant of equity awards. We believe that equity awards create incentives for our executive officers to further our long-term strategic plan to create long-term stockholder value. We also believe equity awards create an ownership culture. In addition, the vesting requirements of our equity awards contributes to executive retention by providing an incentive to our executive officers to remain employed by us during the vesting period.