ImmunityBio, Inc.

As a smaller reporting company for the fiscal year ended December 31, 2023, ImmunityBio is electing to comply with the scaled disclosure requirements applicable to smaller reporting companies pursuant to SEC rules for many of the items that are incorporated by reference into Part III of its Annual Report on Form 10-K. These scaled disclosure requirements include reduced disclosure about the company’s executive compensation arrangements. Please note that certain of the executive compensation disclosure required to be described for a smaller reporting company is presented in tabular form for ease.

The information provided in the “Questions and Answers” format below is for your convenience only and is merely a summary of the information contained in this proxy statement. You should read the entire proxy statement carefully.

Questions and Answers about the Proxy Materials and Annual Meeting

Why am I receiving these materials?

This proxy statement and the enclosed form of proxy are posted in connection with the solicitation of proxies by the Board for use at the 2024 Annual Meeting of Stockholders of ImmunityBio, Inc., a Delaware corporation, and any postponements or adjournments thereof. The Annual Meeting will be held on Tuesday, June 11, 2024 at 9:30 a.m. Pacific Time, via Internet Webcast.

Stockholders are invited to attend the Annual Meeting via Internet Webcast and are requested to vote on the items of business described in this proxy statement. A copy of this proxy statement and our 2023 Annual Report are posted onproxyvote.com, and are also available from the SEC on its website atsec.gov.

What is a proxy?

A proxy is your legal designation of another person to vote the stock you own. The person you designate is your “proxy,” and you give the proxy authority to vote your shares by submitting your proxy card or, if available, voting by telephone or the Internet. We have designated each of Richard Adcock, our Chief Executive Officer and President, Jason Liljestrom, our General Counsel and Corporate Secretary, and David Sachs, our Chief Financial Officer, to serve as proxies for the Annual Meeting.

What am I voting on?

You are being asked to vote on four proposals:

•the election of nine directors from the nominees named in this proxy statement to serve until our 2025 annual meeting of stockholders and until their respective successors are duly elected and qualified or until their earlier resignation or removal;

•an amendment to the ImmunityBio, Inc. 2015 Plan to increase the number of shares of the company’s common stock authorized for issuance under the plan by 19,900,000 shares;

•the approval, on an advisory (non-binding) basis, of the compensation of our Named Executive Officers (“Say-on-Pay”); and

•the ratification of the selection of Ernst & Young LLP as ImmunityBio’s independent registered public accounting firm for the fiscal year ending December 31, 2024.

What if other matters are properly brought before the Annual Meeting?

As of the date of this proxy statement, we are not aware of any other matters that will be presented for consideration at the Annual Meeting. If any other matters are properly brought before the Annual Meeting, the persons named as proxies will be authorized to vote or otherwise act on those matters in accordance with their judgment. If, for any reason, a director nominee is not available as a candidate for director, the persons named as proxy holders will vote your proxy for such other candidate as may be nominated by the Board.

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How does the Board recommend that I vote?

The Board recommends that you vote your shares:

•“FOR” the election of each of the nine nominees for director named in this proxy statement;

•“FOR” the approval of an amendment to the 2015 Plan to increase the number of shares of the company’s common stock authorized for issuance under the plan by 19,900,000 shares;

•“FOR” approval, on an advisory (non-binding) basis, of the Say-on-Pay vote; and

•“FOR” the ratification of the selection of Ernst & Young LLP as ImmunityBio’s independent registered public accounting firm for the fiscal year ending December 31, 2024.

Who may vote at the Annual Meeting?

Only stockholders of record as of the close of business as of the Record Date on April 17, 2024 are entitled to vote at the Annual Meeting. As of the Record Date, there were 677,036,411 shares of our common stock outstanding, held by 89 holders of record.

You are invited to attend the Annual Meeting and vote your shares via Internet Webcast atvirtualshareholdermeeting.com/IBRX2024 by entering the 16-digit Control Number included in our Notice of Internet Availability of Proxy Materials, on your proxy card, or in the instructions that accompanied your proxy materials.

Stockholder of Record: Shares Registered in Your Name. If, at the close of business on the Record Date, your shares were registered directly in your name with our transfer agent, Equiniti Trust Company, LLC, then you are a stockholder of record. As a stockholder of record, you have the right to grant your proxy directly to the individuals listed on the proxy card or to vote via Internet Webcast.

Beneficial Owner: Shares Registered in the Name of a Broker, Bank or Other Nominee. If, at the close of business on the Record Date for the Annual Meeting, your shares were held, not in your name, but rather in an account at a brokerage firm, bank or other nominee, then you are the beneficial owner of shares held in “street name” and these proxy materials will be forwarded to you by that organization. The organization holding your account is considered the stockholder of record for purposes of voting at the Annual Meeting. As a beneficial owner, you have the right to direct your broker, bank or other nominee regarding how to vote the shares in your account by following the voting instructions your broker, bank or other nominee provides or vote via Internet Webcast.

How can I vote my shares?

Stockholder of Record: Shares Registered in Your Name. If you are a stockholder of record, you may vote in one of the following ways:

•You may vote during the Annual Meeting live via the Internet. If you plan to attend the Annual Meeting via Internet Webcast, you may vote your shares via Internet Webcast atvirtualshareholdermeeting.com/IBRX2024 by entering the 16-digit Control Number found in your proxy materials.

•You may vote by mail. Complete, sign and date your proxy card and return it promptly in the postage-prepaid envelope provided (if you requested and received printed proxy materials). Your completed, signed and dated proxy card must be received prior to the Annual Meeting.

•You may vote by telephone. To vote over the telephone, dial toll-free 800-690-6903 and follow the recorded instructions. You will be asked to provide the 16-digit Control Number found in your proxy materials. Telephone voting is available 24 hours a day, 7 days a week. Please note that telephone voting closes at 11:59 p.m. Eastern Time on June 10, 2024.

•You may vote via the Internet. To vote via the Internet, go toproxyvote.com to complete an electronic proxy card. You will be asked to provide the 16 digit Control Number found in your proxy materials. Internet voting is available 24 hours a day, 7 days a week. Please note that Internet voting closes at 11:59 p.m. Eastern Time on June 10, 2024.

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Beneficial Owner: Shares Registered in the Name of a Broker, Bank or Other Nominee. If you are a beneficial owner of shares held of record by a broker, bank or other nominee, you will receive voting instructions from your broker, bank or other nominee. You must follow the voting instructions provided by your broker, bank or other nominee in order to instruct your broker, bank or other nominee on how to vote your shares. Beneficial owners of shares should generally be able to vote by returning the voting instruction form, or by telephone or via the Internet. However, the availability of telephone or Internet voting will depend on the voting process of your broker, bank or other nominee. You may also vote your shares via Internet Webcast atvirtualshareholdermeeting.com/IBRX2024 by entering the 16-digit Control Number found in your proxy materials.

Can I change my vote or revoke my proxy?

Stockholder of Record: Shares Registered in Your Name. If you are a stockholder of record, you can change your vote or revoke your proxy at any time before the Annual Meeting by:

•entering a new vote via the Internet or by telephone (until the applicable deadline for each method as set forth above);

•returning a new proxy card bearing a later date (which automatically revokes the earlier proxy);

•providing a written notice of revocation to ImmunityBio, Inc., Attention: Corporate Secretary, 3530 John Hopkins Court, San Diego, California 92121 that is received before the polls close for voting at the Annual Meeting or any adjournment or postponement thereof; or

•attending the Annual Meeting and submitting your vote live via the Internet prior to the closing of the polls (which would automatically revoke the previously submitted proxy). If you are a stockholder of record, you cannot change your vote in advance of the Annual Meeting using the Internet or telephone voting methods after 11:59 p.m. Eastern Time on June 10, 2024.

Beneficial Owner: Shares Registered in the Name of a Broker, Bank or Other Nominee. If you are a beneficial owner of your shares, you may change your vote by timely submitting new voting instructions to your broker, bank or other nominee (which would revoke your earlier instructions), or by attending the Annual Meeting and submitting your vote live via the Internet prior to the closing of the polls (which would revoke the previously submitted instructions). Beneficial owners of shares should follow the voting instructions provided by their broker, bank or other nominee.

Attending the Annual Meeting will not, in itself, cause your previously granted proxy or previously submitted voting instructions to be revoked. You must submit a new vote during the Annual Meeting prior to the closing of the polls in order to do so.

What is the effect of giving a proxy?

Proxies are solicited by and on behalf of the Board. The persons named in the proxy, Richard Adcock, Jason Liljestrom, and David Sachs, have been designated as proxies for the Annual Meeting by the Board. When proxies are properly dated, executed and returned, the shares represented by such proxies will be voted at the Annual Meeting in accordance with the instruction of the stockholder. If no specific instructions are given, however, the shares will be voted in accordance with the recommendations of the Board as described above and, if any other matters are properly brought before the Annual Meeting, the shares will be voted in accordance with the proxies’ judgment.

How many votes do I have?

For the election of directors, each stockholder is entitled to cast one vote for each director nominee for each share of the company’s common stock held by them as of the Record Date. Cumulative voting is not permitted for the election of directors. On the other matters to be voted upon, each stockholder is entitled to one vote for each share of the company’s common stock held by them as of the Record Date.

What is the quorum requirement for the Annual Meeting?

A quorum is the minimum number of shares required to be present or represented at the Annual Meeting for the meeting to be properly held under our amended and restated bylaws and Delaware law. Holders of a majority of the voting power of the company’s issued and outstanding common stock entitled to vote at the Annual Meeting must be present live via the Internet or represented by proxy to hold and transact business at the Annual Meeting. On the Record Date, there were 677,036,411 shares issued and outstanding and entitled to vote. Thus, the holders of at least 338,518,206 shares must be present in person or represented by proxy at the Annual Meeting to have a quorum.

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Abstentions, “WITHHOLD” votes, and “broker non-votes” are counted as present and entitled to vote for purposes of determining a quorum. If there is no quorum, the chair of the meeting or the holders of a majority of the voting power present live via the Internet or represented by proxy at the Annual Meeting and entitled to vote at the Annual Meeting may adjourn the meeting to another date.

What are broker non-votes?

Broker non-votes occur when a beneficial owner of shares held in street name does not give instructions to the broker holding the shares as to how to vote on matters deemed “non-routine” and there is at least one “routine” matter to be voted upon at the meeting. Generally, if shares are held in street name, the beneficial owner of the shares is entitled to give voting instructions to the broker holding the shares. If the beneficial owner does not provide voting instructions, the broker can still vote the shares with respect to matters that are considered to be routine, but not with respect to non-routine matters. In the event that a broker votes shares on the routine matters but does not vote shares on the non-routine matters, those shares will be treated as broker non-votes with respect to the non-routine proposals. Accordingly, if you own shares through a nominee, such as a broker or bank, please be sure to instruct your nominee how to vote to ensure that your vote is counted on each of the proposals or vote your shares at the meeting.

What matters are considered “routine” and “non-routine”?

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 4) is considered routine under applicable federal securities rules. The election of directors (Proposal 1), the approval of an amendment to the 2015 Plan (Proposal 2), and the approval, on an advisory (non-binding) basis, of the Say-on-Pay vote (Proposal 3) are considered non-routine under applicable rules.

What are the effects of abstentions and broker non-votes?

An abstention represents a stockholder’s affirmative choice to decline to vote on a proposal. If a stockholder indicates on its proxy card that it wishes to abstain from voting its shares, or if a broker, bank or other nominee holding its customers’ shares of record cause abstentions to be recorded for shares, these shares will be considered present and entitled to vote at the Annual Meeting. As a result, abstentions will be counted for purposes of determining the presence or absence of a quorum and will also count as votes against a proposal in cases where approval of the proposal requires the affirmative vote of a majority of the shares present live via the Internet or represented by proxy and entitled to vote at the Annual Meeting, including Proposal 4. However, because the outcome of Proposal 1 (election of directors) will be determined by a plurality vote, abstentions will have no impact on the outcome of such proposal as long as a quorum exists.

Broker non-votes will be counted for purposes of calculating whether a quorum is present at the Annual Meeting but will not be counted for purposes of determining the number of votes cast on a non-routine proposal. Therefore, a broker non-vote will make a quorum more readily attainable but will not otherwise affect the outcome of the vote on any non-routine proposal.

What is the voting requirement to approve each of the proposals?

Proposal 1: Election of Directors. The election of directors requires a plurality of the voting power of shares present live via the Internet or represented by proxy at the Annual Meeting and entitled to vote on the election of directors. This means that the nine nominees for director receiving the highest number of “FOR” votes will be elected as directors. You may vote (i) “FOR” each director or (ii) “WITHHOLD” for each director nominee. Because the outcome of this proposal will be determined by a plurality vote, shares voted “WITHHOLD” will have no impact on the outcome of this proposal but will count towards the quorum requirement for the Annual Meeting.

Proposal 2: Amendment to Increase the Number of Shares Authorized Under the 2015 Plan. Amending the 2015 Plan requires the affirmative “FOR” vote of a majority of the shares present live via the Internet or represented by proxy at the Annual Meeting and entitled to vote thereon to be approved. You may vote “FOR,” “AGAINST,” or “ABSTAIN” on this proposal. Abstentions will count towards the quorum requirement for the Annual Meeting and will have the same effect as a vote against the proposal. Broker non-votes are not deemed to be votes cast, are not included in the tabulation of voting results on this proposal, and will not affect the outcome of voting on this proposal.

Proposal 3: Approval, on an advisory (non-binding) basis, of the Say-on-Pay vote. The affirmative “FOR” vote of a majority of shares of our common stock present live via the internet or represented by proxy at the annual meeting and entitled to vote thereon is required for the approval, on an advisory (non-binding) basis of the Say-on-Pay vote. You may vote “FOR,” “AGAINST,” or “ABSTAIN” on this proposal. Abstentions are deemed to be votes cast and have the same effect as a vote against the proposal. Broker non-votes are not deemed to be votes cast, are not included in the tabulation of voting results on this proposal, and will not affect the outcome of voting on this proposal.

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Proposal 4: Ratification of Selection of Ernst & Young LLP. The ratification of the selection of Ernst & Young LLP requires the affirmative vote of a majority of the shares present live via the Internet or represented by proxy at the Annual Meeting and entitled to vote thereon to be approved. You may vote “FOR,” “AGAINST,” or “ABSTAIN” on this proposal. Abstentions will count towards the quorum requirement for the Annual Meeting and will have the same effect as a vote against the proposal.

Dr. Patrick Soon-Shiong, our Executive Chairman and Global Chief Scientific and Medical Officer, and his affiliates owned, in the aggregate, approximately 78.7% of the company’s outstanding common stock as of the Record Date and has advised us that he intends to vote (1) “FOR” the election of each of the nine nominees for director named in this proxy statement; (2) “FOR” the approval of an amendment to increase the number of shares of our common stock authorized for issuance under the 2015 Plan by 19,900,000; (3) “FOR” the approval, on an advisory (non-binding) basis, of the Say-on-Pay vote; and (4) “FOR” the ratification of the selection of Ernst & Young LLP as ImmunityBio’s independent registered public accounting firm for the fiscal year ending December 31, 2024.

What is the interest of the company’s executive officers and directors in the proposals being voted upon?

None of our executive officers or directors or their associates has any substantial interest in any matter to be acted upon, other than (i) our directors, with respect to the election to office of the directors so nominated, (ii) our directors and executive officers, with respect to the approval of an amendment to the 2015 Plan, because their compensation could be impacted, and (iii) our executive officers, with respect to the non-binding approval of the compensation of our NEOs, because their compensation could be impacted.

What if I do not specify how my shares are to be voted or fail to provide timely directions to my broker, bank or other nominee?

Stockholder of Record: Shares Registered in Your Name. If you are a stockholder of record and you submit a signed proxy but you do not provide voting instructions, your shares will be voted:

•“FOR” the election of each of the nine nominees for director named in this proxy statement;

•“FOR”the approval of an amendment to increase the number of shares of the company’s common stock authorized for issuance under the 2015 Plan by 19,900,000 shares;

•“FOR” the approval, on an advisory (non-binding) basis, of the Say-on-Pay vote; and

•“FOR” the ratification of the selection of Ernst & Young LLP as ImmunityBio’s independent registered public accounting firm for the fiscal year ending December 31, 2024.

In addition, if any other matters are properly brought before the Annual Meeting, the persons named as proxies will be authorized to vote or otherwise act on those matters in accordance with their judgment.

Beneficial Owner: Shares Registered in the Name of a Broker, Bank or Other Nominee. Brokers, banks and other nominees holding shares of common stock in street name for customers are generally required to vote such shares in the manner directed by their customers. In the absence of timely directions, your broker, bank or other nominee will have discretion to vote your shares on our sole routine matter – Proposal 4 to ratify the selection of Ernst & Young LLP. Absent direction from you, however, your broker, bank or other nominee will not have the discretion to vote on Proposal 1 relating to the election of directors, Proposal 2 relating to an amendment to increase the number of shares of our common stock authorized for issuance under the 2015 Plan, and Proposal 3 relating to the approval, on an advisory (non-binding) basis, of the Say-on-Pay vote.

How can I contact ImmunityBio’s transfer agent?

You may contact our transfer agent by writing to Equiniti Trust Company, LLC, 55 Challenger Road, Floor 2, Ridgefield Park, NJ 07660. You may also contact our transfer agent via email at helpAST@equiniti.com or by telephone Monday through Friday from 8:00 a.m. to 8:00 p.m. Eastern Time at 1 800-937-5449 (toll-free) or 1-718-921-8124 (local or international).

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How can I attend the virtual Annual Meeting?

We will host the Annual Meeting online. You will not be able to attend the Annual Meeting in person. A summary of the information you need in order to attend the Annual Meeting online is provided below:

•Any stockholder can attend the Annual Meeting by visiting virtualshareholdermeeting.com/IBRX2024.

•The Annual Meeting starts at 9:30 a.m. Pacific Time on Tuesday, June 11, 2024.

•We encourage you to access the Annual Meeting online prior to its start time.

•Stockholders may vote electronically online while attending the Annual Meeting.

•Please have the Control Number we have provided you to join the Annual Meeting.

•Instructions on how to attend and participate at the Annual Meeting are available atvirtualshareholdermeeting.com/IBRX2024.

•If a stockholder wishes to ask a question of directors and/or members of management in attendance at the Annual Meeting, please note that such questions must be submitted in advance of the Annual Meeting. You may submit your question atproxyvote.com on or before 5:00 p.m. Pacific Time, June 7, 2024 by clicking on the “Submit a Question to Management” button. You will need your 16-digit Control Number to access the website to submit your question.

•Stockholders may vote during the Annual Meeting Internet Webcast atvirtualshareholdermeeting.com/IBRX2024.

Who will count the votes?

A representative of Broadridge Investor Communications, Inc. will tabulate the votes and act as inspector of election.

What happens if the Annual Meeting is adjourned or postponed?

Your proxy will still be effective and will be voted at the rescheduled or adjourned Annual Meeting. You will still be able to change or revoke your proxy until the rescheduled or adjourned Annual Meeting.

Who is paying for the costs of this proxy solicitation?

Your proxy is being solicited by and on behalf of the Board. The expense of preparing, printing and providing this proxy solicitation will be borne by the company. We do not plan to retain a proxy solicitor to assist in the solicitation of proxies. Certain directors, officers, representatives and employees of the company may solicit proxies by telephone and personal interview. Such individuals will not receive any additional compensation from the company for solicitation of proxies, but may be reimbursed by the company for reasonable out-of-pocket expenses in connection with such solicitation. In accordance with the regulations of the SEC, banks, brokers and other custodians, nominees and fiduciaries also will be reimbursed by the company, as necessary, for their reasonable expenses for sending proxy solicitation materials to the beneficial owners of common stock.

Copies of the proxy materials will be supplied to brokers and other nominees for the purpose of soliciting proxies from beneficial owners, and we will reimburse such brokers or other nominees for their reasonable expenses.

If you choose to access the proxy materials and/or vote via the Internet, you are responsible for Internet access charges you may incur. If you choose to vote by telephone, you are responsible for telephone charges you may incur.

How can I find the results of the Annual Meeting?

Preliminary results will be announced at the Annual Meeting. Final results will be published in a Current Report on Form 8-K to be filed with the SEC within four business days after the Annual Meeting. If the official results are not available at that time, we will provide preliminary voting results in the Form 8-K and will provide the final results in an amendment to the Form 8-K as soon as they become available.

When are stockholder proposals due for next year’s annual meeting?

See “Other Matters—Stockholder Proposals for the 2025 Annual Meeting” in this proxy statement for more information regarding the deadlines for the submission of stockholder proposals for the 2025 annual meeting.

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