Geron : Fiscal Year 2024 Proxy

TABLE OF CONTENTS

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. )

Filed by the Registrant ☒

Filed by a Party other than the Registrant

☐

Check the appropriate box:

• ☐ Preliminary Proxy Statement

• ☐ Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2))

• ☒ Definitive Proxy Statement

• ☐ Definitive Additional Materials

• ☐ Soliciting Material Pursuant to §240.14a-12

GERON CORPORATION

(Name of Registrant as Specified In Its Charter)

(Name of Person(s) Filing Proxy Statement, if other than the Registrant)

Payment of Filing Fee (Check all boxes that apply):

• ☒ No fee required.

• ☐ Fee paid previously with preliminary materials.

• ☐ Fee computed on table in exhibit required by Item 25(b) per Exchange Act Rules 14a-6(i)(1) and 0-11

Annual Meeting of Stockholders

Date:

May 9, 2024

Time: 5:00 p.m., Eastern Daylight Time

Place:www.virtualshareholdermeeting.com/GERN2024

YOUR VOTE

IS IMPORTANT TO US.

Whether or not you plan to attend the virtual Annual Meeting, please vote electronically via the Internet or by telephone as instructed in these materials, or, if you have requested and received a paper proxy card by mail, please complete, sign, date and return the proxy card mailed to you, as promptly as possible. Thank you for your ongoing support of, and continued interest in, Geron Corporation.

Dear Fellow Geron Stockholder:

You are cordially invited to attend the 2024 Annual Meeting of Stockholders (the "Annual Meeting") of Geron Corporation to be held on Thursday, May 9, 2024, at 5:00 p.m., Eastern Daylight Time. To facilitate stockholder participation in the Annual Meeting, we have determined that the Annual Meeting will be held in a virtual meeting format only, via the Internet, with no physical in-person meeting. You will be able to attend and participate in the virtual Annual Meeting online by visitingwww.virtualshareholdermeeting.com/GERN2024, where you will be able to listen to the meeting live, submit questions, and vote.

You will not be able to attend the meeting in person. Instructions on how to participate in the virtual Annual Meeting and demonstrate proof of stock ownership are posted atwww.virtualshareholdermeeting.com/GERN2024. The webcast of the virtual Annual Meeting will be archived for one year after the date of the virtual Annual Meeting atwww.virtualshareholdermeeting.com/GERN2024.

As permitted by the rules of the Securities and Exchange Commission, we are pleased to furnish our proxy materials to stockholders primarily over the Internet. Consequently, most stockholders will receive a notice with instructions for accessing proxy materials and voting via the Internet, instead of paper copies of proxy materials. We believe that this process will allow us to provide our stockholders with the information they need in a more timely manner, while reducing the environmental impact and lowering the costs of printing and distributing our proxy materials. However, this notice will provide information on how stockholders may obtain paper copies of proxy materials if they choose. Stockholders who continue to receive hard copies of proxy materials may help us reduce costs by opting to receive future proxy materials by e-mail.

At this year's Annual Meeting, the agenda includes the following items:

Election of the three nominees for director named in the accompanying proxy statement to hold office as Class I members of the Board of Directors until the 2027 annual meeting of stockholders;

Advisory vote to approve named executive officer compensation; andRatification of Ernst & Young LLP as our independent registered public accounting firm.

Sincerely,

John A. Scarlett, M.D.

Chairman of the Board, President and Chief Executive Officer

Notice of Annual Meeting of Shareholders

Date:

May 9, 2024

Time: 5:00 p.m., Eastern Daylight Time

Place:www.virtualshareholdermeeting.com/GERN2024

YOUR VOTE

IS IMPORTANT TO US.

Whether or not you plan to attend the virtual Annual Meeting, please vote electronically via the Internet or by telephone as instructed by these materials, or, if you have requested and received a paper proxy card by mail, please complete, sign, date and return the proxy card mailed to you, as promptly as possible. Stockholders who plan to attend the virtual Annual Meeting should follow the instructions atwww.virtualshareholdermeeting.com/GERN2024 to submit questions and vote during the virtual Annual Meeting. You may log-in beginning at 4:30 p.m. Eastern Daylight Time, on May 9, 2024. You will not be able to attend the meeting in person.

To The Stockholders

NOTICE IS HEREBY GIVEN that the Annual Meeting of Stockholders of GERON CORPORATION, a Delaware corporation (the "Company"), will be held on Thursday, May 9, 2024, at 5:00 p.m., Eastern Daylight Time. To facilitate stockholder participation in the Annual Meeting, we have determined that the Annual Meeting will be held in a virtual meeting format only, via the Internet, with no physical in-person meeting. You can attend the virtual Annual Meeting online, vote your shares electronically and submit your questions during the virtual Annual Meeting, by visitingwww.virtualshareholdermeeting.com/GERN2024. You will need to have your 16-Digit Control Number included in the Notice of Internet Availability of Proxy Materials, on your proxy card or on the instructions that accompanied your proxy materials to join the virtual Annual Meeting.

The Annual Meeting will be held for the following purposes:

To elect the three nominees for director named in the accompanying proxy statement (the "Proxy Statement") to hold office as Class I members of the Board of Directors until the 2027 annual meeting of stockholders;

To approve, on an advisory basis, the compensation of our named executive officers, as disclosed in the Proxy Statement;

To ratify the selection by the Audit Committee of the Board of Directors of Ernst & Young LLP as our independent registered public accounting firm for the fiscal year ending December 31, 2024; and

To transact such other business as may properly come before the Annual Meeting or any postponement or adjournment thereof.

The foregoing items of business are more fully described in the Proxy Statement accompanying this Notice.

The Board of Directors has fixed the close of business on March 12, 2024, as the record date for the determination of stockholders entitled to notice of and to vote at the virtual Annual Meeting and at any adjournment or postponement thereof. Each stockholder is entitled to one vote for each share of common stock held at that time.

By Order of the Board of Directors,

Scott A. Samuels, Esq.

Executive Vice President,

Chief Legal Officer and Secretary Foster City, California

March 27, 2024

Important Notice Regarding the Availability of Proxy Materials for the Annual Meeting to Be Held on

May 9, 2024 atwww.virtualshareholdermeeting.com/GERN2024

The 2024 Proxy Statement and 2023 Annual Report on Form 10-K

are available atwww.proxyvote.com.

YOUR VOTE IS VERY IMPORTANT, REGARDLESS OF THE NUMBER OF SHARES YOU OWN. WHETHER OR NOT YOU EXPECT TO ATTEND THE VIRTUAL ANNUAL MEETING, WE URGE YOU TO VOTE BY PROXY PROMPTLY IN ORDER TO ASSURE THAT A QUORUM IS PRESENT. EVEN IF YOU HAVE VOTED BY PROXY BEFORE THE VIRTUAL ANNUAL MEETING. YOU MAY STILL ATTEND AND VOTE YOUR SHARES AT THE VIRTUAL ANNUAL MEETING ONLINE. YOU WILL NEED TO HAVE

YOUR 16-DIGIT CONTROL NUMBER INCLUDED IN THE NOTICE ON YOUR PROXY CARD OR ON THE INSTRUCTIONS THAT ACCOMPANIED YOUR PROXY MATERIALS TO JOIN AND VOTE AT THE

VIRTUAL ANNUAL MEETING.

Table of Contents

Questions and Answers about these Proxy Materials and Voting 1

Proposal 1: Election of Directors 11

Board Leadership and Governance 22

Other Corporate Governance Matters 32

Compensation of Directors 38

Proposal 2: Advisory Vote to Approve Named Executive Officer Compensation 43

Executive Compensation 45

Proposal 3: Ratification of Selection of Independent Registered Public Accounting

Firm 69

Principal Accountant Fees and Services 70

Audit Committee Report 71

Equity Compensation Plan Information 73

Security Ownership of Certain Beneficial Owners and Management 74

Delinquent Section 16(a) Reports 77

Certain Transactions 77

Other Matters 79

Proxy Statement for the Annual Meeting of Stockholders to be Held on May 9, 2024

Questions and Answers about these Proxy Materials and Voting

Why am I receiving these materials?

You are receiving these materials from us because you owned shares of common stock, par value $0.001 per share ("Common Stock"), of Geron Corporation, a Delaware corporation ("Geron," the "Company," "we" or "us"), as of March 12, 2024, the record date for our 2024 Annual Meeting of Stockholders (the "Annual Meeting"). The Geron Board of Directors (the "Board of Directors" or the "Board") has made these materials available to you in connection with the Board's solicitation of proxies for use at the Annual Meeting. You may vote by proxy over the Internet or by phone, or by mail if you requested printed copies of the proxy materials.

As permitted by the rules of the Securities and Exchange Commission (the "SEC"), we are providing our stockholders access to proxy materials via the Internet. Accordingly, we are sending by mail only a Notice of Internet Availability of Proxy Materials (the "Notice") to certain of our stockholders of record and posting our proxy materials online atwww.proxyvote.com. Stockholders who previously requested to receive hard copies of proxy materials will receive a full set of proxy materials, instead of the Notice. We intend to distribute the Notice and the proxy materials on or about March 29, 2024, to all stockholders of record entitled to vote at the Annual Meeting.

What does it mean if I receive more than one set of proxy materials or more than one Notice, or combination thereof?

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

Will I receive any proxy materials by mail other than the Notice?

No, you will not receive any other proxy materials by mail other than the Notice unless you request paper copies. Pursuant to rules adopted by the SEC, we have elected to use the Internet as the primary means of furnishing proxy materials to our stockholders. This method allows us to deliver the proxy materials to you more quickly, lowers our costs significantly, and helps to conserve natural resources. We encourage stockholders to take advantage of the option to receive proxy materials electronically by email to help reduce the environmental impact of our annual meeting and to reduce costs associated with the physical printing and mailing of materials. This Proxy Statement and our Annual Report on Form 10-K for the year ended December 31, 2023 are also available atwww.proxyvote.com. You may request a full set of proxy materials be sent to your specified postal or email address as follows:

• • by telephone: call 1-800-579-1639 free of charge and follow the instructions;

• • by Internet: go towww.proxyvote.comand follow the instructions; or

• • by e-mail: send an e-mail message [e-mail]. Please send a blank e-mail and insert the 16-Digit Control Number located in your Notice in the subject line. Please make any such request on or before April 25, 2024 to facilitate timely delivery.

Geron Corporation

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2024 Proxy Statement

To sign up for electronic delivery of proxy materials, please follow the instructions provided with your proxy materials and on your proxy card or voting instruction card, to vote using the Internet and, when prompted, indicate that you agree to receive or access future stockholder communications electronically. Alternatively, you can go towww.proxyvote.comand enroll for online delivery of proxy materials. A stockholder's election to receive proxy materials by mail or electronically by email will remain in effect until the stockholder terminates such election.

What is the purpose of the Annual Meeting?

At our Annual Meeting, stockholders will act upon the matters described in this Proxy Statement. In addition, management will report on current events at Geron and respond to questions from stockholders.

How can I participate in the Annual Meeting?

To facilitate stockholder participation in the Annual Meeting, we will be holding our Annual Meeting virtually, on Thursday, May 9, 2024, at 5:00 p.m., Eastern Daylight Time, via the Internet atwww.virtualshareholdermeeting.com/GERN2024. Online check-in will begin at 4:30 p.m. Eastern Daylight Time and you should allow ample time for the check-in procedures. At our virtual Annual Meeting, stockholders will be able to attend, vote and submit questions via the Internet. Whether or not you plan to attend the virtual Annual Meeting, we urge you to vote and submit your proxy in advance of the meeting by one of the methods described in these proxy materials.

You will not be able to attend the virtual Annual Meeting in person.

How do I ask questions at the virtual Annual Meeting?

Our virtual Annual Meeting allows stockholders to submit questions and comments before and during the virtual Annual Meeting. You may submit questions before the virtual Annual Meeting atwww.virtualshareholdermeeting.com/GERN2024. During the virtual Annual Meeting, you may only submit questions in the question box provided atwww.virtualshareholdermeeting.com/GERN2024. In both cases, stockholders must have available their 16-Digit Control Number provided in the Notice or your proxy card (if you received a printed copy of the proxy materials). We will respond to as many inquiries at the virtual Annual Meeting as time allows.

What if during the check-in time or during the virtual Annual Meeting I have technical difficulties or trouble accessing the virtual meeting website?

We will have technicians ready to assist you with any technical difficulties you may have accessing the virtual meeting website. If you encounter any difficulties accessing the virtual Annual Meeting during the check-in or meeting time, please call the technical support number that will be posted on the virtual Annual Meeting website log-in page.

What if I cannot virtually attend the Annual Meeting?

You may vote your shares electronically before the virtual Annual Meeting by Internet, or by telephone or by mail as described below. You do not need to access the virtual Annual Meeting to vote if you submitted your vote by Internet, by telephone or by mail in advance of the virtual Annual Meeting.

The virtual Annual Meeting will be archived for one year after the date of the virtual Annual Meeting atwww.virtualshareholdermeeting.com/GERN2024.

Geron Corporation

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2024 Proxy Statement

Who can vote at the virtual Annual Meeting?

Only holders of record at the close of business on March 12, 2024 (the "Record Date") will be entitled to notice of and to vote at the virtual Annual Meeting or any adjournment or postponement thereof. At the close of business on the Record Date, we had 546,873,894 shares of Common Stock outstanding.

Stockholder of Record: Shares Registered in Your Name

Each holder of record of Common Stock on the Record Date will be entitled to one vote for each share held on all matters to be voted upon at the virtual Annual Meeting. As a stockholder of record, you may vote at the virtual Annual Meeting, or prior to the virtual Annual Meeting, vote through the Internet or by telephone, or by mail using a proxy card that you received or that you may request. Whether or not you plan to attend the virtual Annual Meeting, we urge you vote by proxy through the Internet or by telephone as instructed below, or by completing a proxy card that you may request or that we may elect to deliver at a later time. Stockholders who attend the virtual Annual Meeting should follow the instructions atwww.virtualshareholdermeeting.com/ GERN2024 to vote during the virtual Annual Meeting.

For the ten days ending the day prior to the virtual Annual Meeting, a list of our stockholders of record as of the Record Date will be available for examination by any stockholder of record for any purpose germane to the virtual Annual Meeting at our corporate headquarters during regular business hours. To access the list of record stockholders during the ten days ending the day prior to the Annual Meeting, stockholders should [e-mail].

Beneficial Owner: Shares Registered in the Name of a Broker or Bank

If on the Record Date 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 during the virtual 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 virtual Annual Meeting. You can attend the virtual Annual Meeting online by visitingwww.virtualshareholdermeeting.com/GERN2024. You will need to have your 16-Digit Control Number included in the Notice, on your proxy card or on the instructions that accompanied your proxy materials to join the virtual Annual Meeting. Once you join the virtual Annual Meeting, you should follow the instructions on the virtual Annual Meeting platform to vote during the virtual Annual Meeting. If you did not receive a 16-digit control number via email or on your Notice or voting instruction form, and you wish to vote prior to or at the virtual Annual Meeting, you must follow the instructions from your broker or other agent.

What is the quorum requirement?

A quorum of stockholders is necessary to hold a valid meeting. In order to constitute a quorum and to transact business at the virtual Annual Meeting, the holders of a majority of the voting power of the Common Stock issued and outstanding and entitled to vote at the virtual Annual Meeting must be present in person or represented by proxy. Virtual attendance at our Annual Meeting constitutes presence in person for purposes of a quorum at the meeting. Shares represented by proxies that reflect abstentions or "broker non-votes" will be counted for purposes of determining the presence of a quorum.

Geron Corporation

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2024 Proxy Statement

What am I voting on at the virtual Annual Meeting? What is the Board's recommendation on each of the proposals?

You are being asked to vote on three proposals, as follows:

Proposal NumberProposalBoard Recommends

To elect the three nominees for director named in this Proxy Statement to hold office as Class I members of our Board of Directors until the 2027 annual meeting of stockholders.

FOR ALL director nominees

To approve, on an advisory basis, the compensation of our named executive officers, as disclosed in this Proxy Statement.

FOR

To ratify the selection by the Audit Committee of the Board of Directors of Ernst & Young LLP as our independent registered public accounting firm for the fiscal year ending December 31, 2024.

FOR

How many votes are needed to approve each proposal? What is the effect of abstentions and broker non-votes on each of the proposals?

The following table summarizes the minimum vote needed to approve each proposal and the effect of abstentions and broker non-votes on each of the proposals:

Proposal NumberProposal

Votes Required to Approve Proposal(1)Effect ofEffect of AbstentionsBroker Non-Votes

To elect the three nominees for director named in this Proxy Statement to hold office as Class I members of our Board of Directors until the 2027 annual meeting of stockholders.

Nominees receiving a plurality of the votes cast will be elected as directors This means that the nominees receiving the highest number of "FOR" votes at the virtual Annual Meeting will be elected, even if those votes do not constitute a majority of the votes cast. Only votes "FOR" will affect the outcome of the vote; "WITHHOLD" votes will have no effect on the outcome of the vote. However, under our Corporate Governance Guidelines, any nominee for director who receives a greater number of "WITHHOLD" votes from his or her election than votes "FOR" such election is required to submit an offer of resignation for consideration by the Nominating and Corporate Governance Committee. In such case, the Nominating and Corporate Governance Committee will then consider all of the relevant facts and circumstances and recommend to the Board the action to be taken with respect to such offer of resignation.

Not applicableNo effectTo approve, on an advisory basis, the compensation of our named executive officers, as disclosed in this Proxy Statement.

The affirmative vote of the holders of a majority of the voting power present in person or represented by proxy at the virtual Annual Meeting.

Against

No effectTo ratify the selection by the Audit Committee of the Board of Directors of Ernst & Young LLP as our

The affirmative vote of the holders of a majority of the voting power present in person or represented by proxy at the virtual Annual

Against

Not applicable(2)

Geron Corporation

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2024 Proxy Statement

Effect ofProposal NumberProposal

Votes Required to Approve Proposal(1)Effect of Abstentions

Broker Non-Votes

independent registered public accounting firm for the fiscal year ending December 31, 2024.

Meeting.

• (1) Virtual attendance at our Annual Meeting constitutes presence in person for purposes of the votes.

• (2) This proposal is considered to be a "routine" matter under NYSE rules. Accordingly, if you hold your shares in street name and do not provide voting instructions to your broker, bank or other agent that holds your shares, your broker, bank or other agent has discretionary authority under applicable NYSE rules to vote your shares on this proposal. For more information, see "If I am a beneficial owner of shares held in street name and I do not provide my broker or bank with my voting instructions, what happens?" and "What are broker non-votes?" below.

What are the choices in voting?

For Proposal 1, you may either vote "FOR" all nominees to the Board of Directors or you may "WITHHOLD" your vote for one or more nominees that you specify. For proposals 2 and 3, you may vote "FOR" the proposal or "AGAINST" the proposal, or "ABSTAIN" from voting on the proposal.

Could other matters be decided at the virtual Annual Meeting?

The Board does not know of any other matters to be brought before the virtual Annual Meeting. Our Bylaws require that we receive advance notice of any proposal to be brought before the Annual Meeting by our stockholders, and we have not received notice of any such proposals. If any other matters were to be properly submitted for a vote at the virtual Annual Meeting, the proxy holders appointed by the Board will have the discretion to vote on those matters for you as they see fit.

How do I vote my shares and what are the voting deadlines?

Please refer to the proxy card for instructions on, and access information for, voting by telephone, over the Internet or by mail.

Stockholder of Record: Shares Registered In Your Name

You are a stockholder of record if, on the Record Date, your shares were registered directly in your name with our transfer agent, Computershare Trust Company, N.A. As a stockholder of record, there are several ways for you to vote your shares.

• • Via the Internet Before the Virtual Annual Meeting.

  You may vote by Internet atwww.proxyvote.com, 24 hours a day, seven days a week. You will need the 16-Digit Control Number included on your Notice, your proxy card (if you received a printed copy of the proxy materials) or the instructions that accompanied your proxy materials to join the virtual Annual Meeting. Votes submitted through the Internet must be received by 11:59 p.m., Eastern Daylight Time, on May 8, 2024.

• • By Telephone.

  You may vote using a touch-tone telephone by calling 1-800-690-6903, 24 hours a day, seven days a week. You will need the 16-Digit Control Number included on your Notice, your proxy card (if you received a printed copy of the proxy materials) or the instructions that accompanied your proxy materials to join the virtual Annual Meeting. Votes submitted by telephone must be received by 11:59 p.m., Eastern Daylight Time, on May 8, 2024.

• • By Mail.

  If you received printed proxy materials, you may submit your vote by completing, signing, and dating each proxy card received and returning it in the postage-paid envelope. Sign your name exactly as it appears on the proxy card. Proxy cards submitted by mail must be received no later than close of business on May 8, 2024, to be voted at the virtual Annual Meeting.

Geron Corporation

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2024 Proxy Statement

• • Via the Internet During the Virtual Annual Meeting. Stockholders who attend the virtual Annual Meeting should follow the instructions atwww.virtualshareholdermeeting.com/GERN2024to vote during the virtual Annual Meeting. You will need the 16-Digit Control Number included on your Notice, your proxy card (if you received a printed copy of the proxy materials) or the instructions that accompanied your proxy materials to join the virtual Annual Meeting.

The Internet and telephone voting procedures described above, which comply with Delaware law, are designed to authenticate stockholders' identities, to allow stockholders to vote their shares, and to confirm that their instructions have been properly recorded. However, please be aware that you must bear any costs associated with your Internet access, such as usage charges from Internet access providers and telephone companies.

Beneficial Owner: Shares Registered in the Name of a Broker or Bank

You are a beneficial owner, if on the Record Date, your shares were held in an account at a brokerage firm, bank, dealer, or other similar organization and not in your name. The organization holding your account is considered to be the stockholder of record for purposes of voting at the virtual Annual Meeting. Being a beneficial owner means that, like most stockholders, your shares are held in "street name" and these proxy materials are being forwarded to you by that organization.

As a beneficial owner, you should have received a Notice or voting instructions from the broker or other nominee holding your shares. You should follow the instructions in the Notice or voting instructions provided by your broker or nominee in order to instruct your broker or other nominee on how to vote your shares. The availability of telephone and Internet voting will depend on the voting process of the broker or nominee. Please contact your bank, broker or other agent if you have questions about their instructions on how to vote your shares. Please also note that since you are not the stockholder of record, you may only vote your shares during the virtual Annual Meeting if using the 16-Digit Control Number included on your Notice. Beneficial owners who attend the virtual Annual Meeting should follow the instructions atwww.virtualshareholdermeeting.com/ GERN2024 to vote during the virtual Annual Meeting. You will need the 16-Digit Control Number included on your Notice, your proxy card (if you received a printed copy of the proxy materials) or the instructions that accompanied your proxy materials to join the virtual Annual Meeting.

The ratification of the selection of Ernst & Young LLP as our independent registered public accounting firm for the fiscal year ending December 31, 2024 (Proposal 3) is considered to be a "routine" matter under NYSE rules. Accordingly, if you do not provide your broker or bank with instructions on how to vote your shares, your broker or bank would be able to vote your shares under applicable NYSE rules on Proposal 3. For more information, see "If I am a beneficial owner of shares held in street name and I do not provide my broker or bank with my voting instructions, what happens?" and "What are broker non-votes?" below.

Geron Plan Participants

If you are a participant in the Geron 401(k) Plan (the "Plan"), your proxy card serves to direct Fidelity Management Trust Company ("Fidelity") how to direct the shares credited to your account in the Plan. Unless otherwise required by law, Fidelity will follow your instructions. If your proxy card is not received by May 6, 2024, the shares allocated to your account will not be voted.

If you purchased shares through the 2014 Employee Stock Purchase Plan, as amended, and your shares are held in the name of a broker, please refer to the discussion above under "Beneficial Owner: Shares Registered in the Name of a Broker or Bank."

Geron Corporation

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2024 Proxy Statement