Schedule 14A (Definitive Additional Materials)

DEFA14A 1 schedule14adefinitiveaddit.htm DEFA14A Schedule 14A (Definitive Additional Materials)

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

SCHEDULE 14A

(Rule 14a-101)

SCHEDULE 14A INFORMATION

Proxy Statement Pursuant to Section 14(a) of the

Securities Exchange Act of 1934

Filed by the Registrant ý

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

ý Definitive Additional Materials

☐ Soliciting Material Pursuant to Section 240.14a-12.

ROCKET LAB 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):

ý 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.

Your Vote Counts! Smartphone users Point your camera here and vote without entering a control number For complete information and to vote, visit www.ProxyVote.com Control # V90558-P50791 *Please check the meeting materials for any special requirements for meeting attendance. ROCKET LAB CORPORATION 3881 MCGOWEN ST LONG BEACH, CA 90808 ROCKET LAB CORPORATION 2026 Annual Meeting Vote by May 19, 2026 11:59 PM ET You invested in ROCKET LAB CORPORATION and it’s time to vote! You have the right to vote on proposals being presented at the Annual Meeting. This is an important notice regarding the availability of proxy materials for the stockholder meeting to be held on May 20, 2026. Vote Virtually at the Meeting* May 20, 2026 1:30 PM Pacific Time Virtually at: www.virtualshareholdermeeting.com/RKLB2026 Get informed before you vote View the Notice and Proxy Statement and Annual Report online OR you can receive a free paper or email copy of the material(s) by requesting prior to May 6, 2026. If you would like to request a copy of the material(s) for this and/or future stockholder meetings, you may (1) visit www.ProxyVote.com, (2) call 1-800-579-1639 or (3) send an email to sendmaterial@proxyvote.com. If sending an email, please include your control number (indicated below) in the subject line. Unless requested, you will not otherwise receive a paper or email copy.

Vote at www.ProxyVote.com Prefer to receive an email instead? While voting on www.ProxyVote.com, be sure to click “Delivery Settings”. Voting Items Board Recommends V90559-P50791 THIS IS NOT A VOTABLE BALLOT This is an overview of the proposals being presented at the upcoming stockholder meeting. Please follow the instructions on the reverse side to vote these important matters. 1. Election of Class II Director Nominee: To be elected for term expiring in 2029 1a. Edward H. Frank For 2. To ratify the appointment of Deloitte & Touche LLP as our independent registered public accounting firm for the fiscal year ending December 31, 2026. For 3. To approve, on a non-binding advisory basis, the compensation of our named executive officers disclosed in the accompanying proxy statement. For 4. To approve a subsidiary merger 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 Company’s wholly owned subsidiary. For NOTE: The proxy holders will vote, in their discretion, on any other business as may properly come before the meeting or any adjournments or postponements thereof.

SEC Form DEFA14A filed by Rocket Lab Corporation