UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934

Date of Report (Date of earliest event reported): May 8, 2026

ROCKET LAB CORPORATION

(Exact name of Registrant as Specified in Its Charter)

Registrant’s Telephone Number, Including Area Code: 714 465-5737

Not Applicable

(Former Name or Former Address, if Changed Since Last Report)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

☐ Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

☐ Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

☐ Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

☐ Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Securities registered pursuant to Section 12(b) of the Act: 

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§ 230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§ 240.12b-2 of this chapter).

Emerging growth company ☐

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

Item 8.01 Other Events.

On May 8, 2026, Rocket Lab Corporation (the “Company”) filed with the Securities and Exchange Commission (the “SEC”) a prospectus supplement to the prospectus included in the Company’s registration statement on Form S-3ASR filed with the SEC on March 11, 2025 (File No. 333-285707), as amended by the Post-Effective Amendment No. 1 filed with the SEC on May 27, 2025 (the “Registration Statement”), covering the resale by certain selling stockholders of up to 2,277,002 shares of the Company’s Common Stock in the aggregate issued on April 14, 2026 in a private placement in connection with the previously announced acquisition of Mynaric AG, pursuant to a Stock Purchase Agreement, dated as of September 25, 2025, by and among the Company, Rocket Lab USA, Inc., OC III LVS LIII LP, CO Finance II LVS I LLC, Rocket Lab Germany GmbH via joinder dated April 13, 2026 and OC IV LVS VI LP via joinder dated April 13, 2026 (the “Stock Purchase Agreement”). The prospectus supplement was filed in accordance with the Stock Purchase Agreement. A copy of the legal opinion of Goodwin Procter LLP relating to the shares covered by the prospectus supplement is filed herewith as Exhibit 5.1, and is filed with reference to, and is hereby incorporated by reference in, the Registration Statement.

Item 9.01 Financial Statements and Exhibits.

(d) Exhibits

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.