Rocket Lab Corp

Insider Trading Arrangements

During the three months ended June 30, 2026, certain executive officers and a director of the Company (each, a “Plan Participant”) entered into a 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 shares issuable to Mr. Spice upon the exercise of all outstanding 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 RSU Shares 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 such RSU awards. Additionally, certain provisions within the Rule 10b5-1 Trading Plan specify a certain percentage of the net shares that can be sold at the vesting date of the underlying equity award. 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, adjusted to represent the maximum percentage specified in the plan for each vesting date of such award, but without excluding the shares that will be sold to satisfy the tax withholding obligations.

On June 3, 2026, Mr. Spice terminated his Rule 10b5-1 trading plan, originally adopted on March 27, 2026. No shares of common stock were sold pursuant to Mr. Spice’s terminated 10b5-1 trading plan.

Sell to Cover Trading Election

On May 12, 2026, Marvin Bradford Clevenger, Rocket Lab USA’s President (the “Participant”), entered into a Rule 10b5-1 trading arrangement that is 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 plan will apply to all RSUs granted to the 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 election is effective 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 this election will vary based on the tax withholding obligations incurred upon vesting.