Rocket Lab Corp

This proxy statement contains information about the 2025 annual meeting of shareholders of Rocket Lab Corporation. In this proxy statement both “Rocket Lab”, the “Company”, “we”, “us”, or “our” refer to Rocket Lab Corporation and its consolidated subsidiaries, unless the context indicates otherwise. On May 8, 2025, the Rocket Lab USA, Inc. announced plans to implement a holding company reorganization (the “Holding Company Reorganization”) pursuant to Section 251(g) of the Delaware General Corporation Law (the “DGCL”). On May 23, 2025, the Rocket Lab USA, Inc. implemented the Holding Company Reorganization, whereby the Rocket Lab USA, Inc. became a wholly owned subsidiary of the Company and the Company became the new parent company of and the successor issuer to the Predecessor. Pursuant to the Holding Company Reorganization, all of the Rocket Lab USA, Inc.’s outstanding shares were automatically converted into equivalent corresponding shares of the Company.

Why did I receive a notice regarding the availability of proxy materials on the internet?

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 Company’s Board of Directors (the “Board”) is soliciting your proxy to vote at the 2025 Annual Meeting of Stockholders (the “Annual Meeting”) and at any adjournments, continuances or postponements of the Annual Meeting. The Annual Meeting will be held virtually via live interactive webcast on the internet on August 27, 2025, at 1:30 p.m. Pacific Daylight Time. If you held shares of our common stock (the “Common Stock”) or our Series A Convertible Participating Preferred Stock (“Series A Preferred Stock”, and together with the Common Stock, “capital stock”) on July 9, 2025 (the “Record Date”), you are invited to attend the Annual Meeting atwww.virtualshareholdermeeting.com/rklb2025 and vote on the proposals described below under the heading “What am I voting on?”

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. The Notice is being mailed to stockholders commencing on or about July 11, 2025.

What am I voting on?

There are four proposals scheduled to be voted on at the Annual Meeting:

1. Election of three Class I director nominees specified in this Proxy Statement to serve until the 2028 Annual Meeting of Stockholders and until their respective successors are elected and qualified;

2. Ratification of the appointment of Deloitte & Touche LLP as our independent registered public accountants for the fiscal year ending December 31, 2025;

3. To approve, on a non-binding advisory basis, the compensation of our named executive officers disclosed in the Proxy Statement (the “Say-on-Pay Proposal”);

4. To approve an amendment to the Amended and Restated Certificate of Incorporation of the Rocket Lab USA, Inc. to eliminate the recently added pass-through voting provision that requires approval by both the Company and the Company’s stockholders prior to certain actions being taken by or at the Rocket Lab USA, Inc. (the “Rocket Lab USA, Inc. Charter Amendment Proposal”).

How does the Board recommend that I vote?

Our Board recommends that you vote your shares:

“FOR” the election of each of the three Class I director nominees named in this Proxy Statement to hold office until the 2028 Annual Meeting of Stockholders and until their respective successors are elected and qualified;

“FOR” the ratification of the appointment of Deloitte & Touche LLP as our independent registered public accountants for the fiscal year ending December 31, 2025;

“FOR” the approval, on a non-binding advisory basis, of the Say-on-Pay Proposal; and

“FOR” the approval of the Rocket Lab USA, Inc. Charter Amendment Proposal.

Who can vote at the Annual Meeting?

Holders of record of the Company’s Common Stock and Series A Preferred Stock as of the close of business on July 9, 2025, the Record Date for the Annual Meeting, are entitled to vote at the Annual Meeting. As of July 9, 2025, there were 479,338,705 shares of Rocket Lab Common Stock outstanding, excluding treasury shares, and 45,951,250 shares of Rocket Lab’s Series A Preferred Stock, which votes together as a single class with the Common Stock on an as-converted one-for-one basis. Company treasury shares will not be voted. Each stockholder has one vote for each share of Common Stock held as of the Record Date, and each holder of Series A Preferred Stock will have one vote for each share of Series A Preferred Stock held as of the Record Date, voting together as a single class.

If, on the Record Date, your shares were held in an account at a broker, bank or other financial institution (we will refer to those organizations collectively as “broker”), then you are the beneficial owner of shares held in “street name” and these proxy materials are being forwarded to you by that broker. The broker holding your account is considered the stockholder of record for purposes of voting at the Annual Meeting. As the beneficial owner, you have the right to direct your broker on how to vote the shares in your account. As a beneficial owner, you are invited to attend the Annual Meeting via the internet atwww.virtualshareholdermeeting.com/rklb2025. However, since you are not a stockholder of record, you may not vote your shares at the Annual Meeting unless you request and obtain a valid proxy from your broker.

How can I attend the Annual Meeting?

If you are a stockholder of record or a beneficial owner as of the Record Date, you are invited to attend the Annual Meeting live via the internet atwww.virtualshareholdermeeting.com/rklb2025. You must have your 16-digit control number listed on your Notice, the proxy card or in the instructions that accompanied your proxy materials to enter the meeting. The webcast starts at 1:30 p.m. Pacific Daylight Time. You may vote and submit questions while attending the meeting on the internet. Instructions on how to attend and participate in the Annual Meeting via the internet, including how to demonstrate proof of stock ownership, are posted atwww.virtualshareholdermeeting.com/rklb2025. The audio broadcast will be archived on that website for one year after the date of the Annual Meeting.

What if I return the proxy card to the Company but do not make specific choices?

If you return a signed, dated, proxy card to the Company without making any voting selections, the named proxies will vote your shares at the Annual Meeting or at any postponement or adjournment thereof, (1) “FOR” the election of each of the three Class I director nominees named in this Proxy Statement to hold office until the 2028 Annual Meeting of Stockholders and until their respective successors are elected and qualified; (2) “FOR” the ratification of the appointment of Deloitte & Touche LLP as our independent registered public accountants for the fiscal year ending December 31, 2025; (3) “FOR” the approval, on a non-binding advisory basis, of the Say-on-Pay Proposal; and (4) “FOR” the approval of the Rocket Lab USA, Inc. Charter Amendment Proposal.

The Company does not expect that any matters other than the election of directors and the other proposals described in this Proxy Statement will be brought before the Annual Meeting. The persons appointed as proxies will vote in their discretion on any other matters that may properly come before the Annual Meeting or any postponements or adjournments thereof, including any vote to postpone or adjourn the Annual Meeting.

How many shares must be present or represented to conduct business at the Annual Meeting?

A quorum of stockholders is necessary to hold a valid annual meeting. A quorum will be present if the holders of at least a majority of the outstanding number of shares of Common Stock and Series A Preferred Stock entitled to vote are present, in person or by proxy, at the Annual Meeting. Abstentions and shares represented by broker non-votes are counted for the purpose of determining whether a quorum is present. If there are insufficient votes to constitute a quorum at the time of the Annual Meeting, the holders of voting stock representing a majority of the voting power present at the meeting or the presiding officer may adjourn the Annual Meeting to another place (if any), date or time and from time to time.

How are votes counted and what is a broker non-vote?

Votes will be counted by the inspector of election appointed for the Annual Meeting. A “broker non-vote” occurs when your broker submits a proxy card for your shares of Common Stock held in street name, but does not vote on a particular proposal because the broker has not received voting instructions from you and does not have the authority to vote on that matter without instructions. Under the rules that govern brokers who are voting shares held in street name, brokers have the discretion to vote those shares on routine matters but not on non-routine matters. For purposes of these rules, the only routine matter in this Proxy Statement is Proposal Two—the ratification of our independent registered public accounting firm for the fiscal year ending December 31, 2025. Proposals One, Three and Four are non-routine matters. Therefore, if you hold your shares in street name and do not provide voting instructions to your broker, your broker does not have discretion to vote your shares on any proposal at the Annual Meeting other than Proposal Two—the ratification of our independent registered public accounting firm for the fiscal year ending December 31, 2025. However, your shares will be considered present at the Annual Meeting for purposes of determining the existence of a quorum.

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

Proposal One—Election of Class I directors

The election of Class I director nominees requires a plurality vote of the shares present in person or represented by proxy at the Annual Meeting and entitled to vote in the election of directors. The director nominees receiving the highest number of “FOR” votes cast by the holders of Common Stock and Series A Preferred Stock entitled to vote at the Annual Meeting will be elected. Accordingly, “WITHHOLD” votes and broker non-votes will have no effect on the outcome of the election of directors. Stockholders have no right to cumulative voting as to any matters, including the election of directors.

Proposal Two—Ratification of the Appointment of our Independent Registered Public Accounting Firm for the Fiscal Year Ending December 31, 2025

The proposal to ratify the appointment of Deloitte & Touche LLP requires the affirmative vote of a majority of the of the votes properly cast “FOR” or “AGAINST” this proposal. Abstentions and Broker non-votes will have no effect on the results of this vote. Brokers have discretionary authority to vote uninstructed shares on this proposal.

Proposal Three—Non-Binding Advisory Vote to Approve the Compensation of Our Named Executive Officers

The proposal to approve the compensation of our named executive officers, on a non-binding advisory basis, requires the affirmative vote of a majority of the of the votes properly cast “FOR” or “AGAINST” such proposal. Abstentions and broker non-votes will have no effect on the results of this vote. Because your vote is advisory, it will not be binding on the Board or our Compensation Committee, but the Board and Compensation Committee will review the voting results and take them into consideration when making future decisions about executive compensation. Brokers do not have discretionary authority to vote uninstructed shares on this proposal.

Proposal FOUR—To approve an amendment to the Amended and Restated Certificate of Incorporation of Rocket Lab USA, Inc., the Company’s wholly owned subsidiary, to eliminate the recently added pass-through voting provision that requires approval by both the Company and the Company’s stockholders prior to certain actions being taken by or at Rocket Lab USA, Inc.

The proposal to approve an amendment to the Amended and Restated Certificate of Incorporation of the Rocket Lab USA, Inc. to eliminate the recently added pass-through voting provision that requires approval by both the Company and the Company’s stockholders prior to certain actions being taken by or at the Predecessor, requires the affirmative vote of not less than sixty-six and two-thirds percent (66-2/3%) of the voting power of the outstanding shares of capital stock entitled to vote thereon. Abstentions and broker non-votes will have the effect of a vote against this proposal. Brokers do not have discretionary authority to vote uninstructed shares on this proposal.

How do I vote my shares?

Stockholders may vote their shares of capital stock using any of the following means:

Voting by Proxy Cards. A registered stockholder may vote shares until voting is completed at the Annual Meeting by requesting and returning a duly completed and executed proxy card. All proxy cards received by us that have been properly signed and have not been revoked will be voted in accordance with the instructions contained in the proxy cards. For your mailed proxy card to be counted, we must receive it prior to the close of business on August 26, 2025.

Voting by Telephone or Internet. A registered stockholder may vote shares until 11:59 p.m. Eastern Daylight Time on August 26, 2025 by calling the toll-free number indicated on the Notice and following the recorded instructions or by accessing the website indicated on the Notice and following the instructions provided. When a stockholder votes by telephone or internet, his, her or its vote is recorded immediately.

Voting by Internet During the Annual Meeting. Instructions on how to attend and vote at the meeting are described atwww.virtualshareholdermeeting.com/rklb2025. If a stockholder attends the Annual Meeting and votes his, her or its shares during the meeting via the voting instructions described atwww.virtualshareholdermeeting.com/rklb2025, then any previous votes that were submitted by the stockholder, whether by internet, telephone or mail, will be superseded by the vote that such stockholder casts during the Annual Meeting. Further, if the shares are held of record by a broker and a stockholder wishes to vote at the Annual Meeting, he, she or it must obtain a proxy issued in his, her or its name from the record holder in accordance with the materials and instructions for voting provided by his, her or its broker.

Voting by “Street Name” Stockholders. If stockholders hold shares in “street name,” then those stockholders may vote in accordance with the materials and instructions for voting the shares provided by their broker. If “street name” stockholders wish to vote shares at the Annual Meeting, then they must obtain proxies from their broker in order to vote their shares at the Annual Meeting in accordance with the materials and instructions for voting provided by his, her or its broker. If a “street name” stockholder does not vote by proxy or otherwise give voting instructions to their broker, such shares will not be voted by the broker for Proposal One at the Annual Meeting.

Changing Votes. A registered stockholder may change his, her or its vote at any time before it is voted at the Annual Meeting by (1) delivering a proxy revocation or another duly executed proxy bearing a later date to Rocket Lab Corporation, 3881 McGowen Street, Long Beach CA 90808, Attention: Corporate Secretary, which revocation or later-dated proxy is received by us prior to the close of business on August 26, 2025; (2) voting again by telephone or internet in the manner described above prior to 11:59 p.m., Eastern Daylight Time, on August 26, 2025; or (3) attending the Annual Meeting and voting via the internet during the meeting using the procedures described atwww.virtualshareholdermeeting.com/rklb2025. Attending the Annual Meeting via the internet will not revoke a proxy unless the stockholder actually votes via the internet during the meeting. “Street name” stockholders who wish to revoke or change their votes after returning voting instructions to their broker may do so in accordance with the materials and instructions provided by their broker or by contacting such broker to effect the revocation or change of vote.

If you have any questions or need assistance with voting, please contact Okapi Partners LLC, our proxy solicitor, info@okapipartners.com at 1-844-343-2621 (for shareholders) or 212-297-0720 (for banks and brokers).

Who will pay for the cost of this proxy solicitation?

We will pay the cost of soliciting proxies. Proxies may be solicited on our behalf by directors, officers or employees (for no additional compensation) in person or by telephone, facsimile or electronic transmission. Brokers and other nominees will be requested to solicit proxies or authorizations from beneficial owners and will be reimbursed for their reasonable expenses.

We also have retained Okapi Partners LLC to assist in soliciting proxies. We expect to pay Okapi Partners approximately $15,000 plus expenses in connection with its solicitation of proxies.

How can I find out the results of the Annual Meeting?

Preliminary voting results will be announced at the Annual Meeting. We will publish final results in a Current Report on Form 8-K that we expect to file with the SEC within four business days after the Annual Meeting. After the Form 8-K is filed, you may obtain a copy by visiting the investor relations section of our website athttps://investors.rocketlabcorp.com or by writing to Rocket Lab Corporation, 3881 McGowen Street, Long Beach CA 90808, Attention: Corporate Secretary.