Rocket Lab Corp

Insider Trading Arrangements

During the three months ended September 30, 2025, certain executive officers and directors of the Company (each, a “Plan Participant”) entered into Rule 10b5-1 trading plan (a “Rule 10b5-1 Trading Plan”) to sell shares of the Company’s common stock subject to any applicable volume limitations.

The table below provides certain information regarding each Plan Participant’s Rule 10b5-1 Trading Plan.

(1) Represents 634,335 shares held by Mr. Spice and 731,330 shares issuable to Mr. Spice upon the exercise of approximately 22% of the vested stock options held by Mr. Spice as of the date of the Rule 10b5-1 Trading Plan, all of which are scheduled to expire in August 2028.

(2) The aggregate number of shares issuable upon the vesting and settlement of restricted stock units (“RSUs”) that will be available for sale under the Rule 10b5-1 Trading Plan is not yet determinable because the shares available will be net of shares sold to satisfy tax withholding obligations that arise in connection with the vesting and settlement of the related RSU awards. As such, for purposes of this disclosure, the shares included in this table reflect the aggregate maximum number of gross shares underlying the equity awards subject to the Rule 10b5-1 Trading Plan but without excluding the shares that will be sold to satisfy the tax withholding obligations upon vesting.

Sell to Cover Trading Elections

On September 19, 2025, each of: Adam Spice, Chief Financial Officer; Arjun Kampani, Senior Vice President, General Counsel and Corporate Secretary; and Frank Klein, Chief Operations Officer (together, the “Participants”), entered into Rule 10b5-1 trading arrangements that are each intended to qualify as a “plan providing for eligible sell-to-cover transactions" under Rule 10b5-1(c)(1)(ii)(D)(3) under the Exchange Act. The plans will apply to all RSUs granted to each Participant by the Company, whether granted prior to the date of the election or on or subsequent to the date of the election, pursuant to the Company’s 2021 Stock Option and Incentive Plan or any successor equity incentive plan. The sell-to-cover election provides for the sale of shares of common stock issued upon the vesting of restricted stock units in an amount sufficient to cover the federal, state, local, and foreign tax withholding obligations incurred in connection with such vesting.

The sell-to-cover elections are effective from December 19, 2025 until December 31, 2027, unless terminated earlier due to specified events, such as the individual’s death or legal or regulatory restrictions. The number of shares sold under these elections will vary based on the tax withholding obligations incurred upon vesting.