X0508 4 2025-09-18 0 0001819994 Rocket Lab Corp RKLB 0001509421 Spice Adam C. 3881 MCGOWEN STREET LONG BEACH CA 90808 0 1 0 0 Chief Financial Officer 0 Common Stock 2025-09-18 4 M 0 1867496 1.09 A 2932477 D Common Stock 2025-09-19 4 S 0 862588 47.9941 D 2069889 D Common Stock 2025-09-19 4 S 0 12000 48.8484 D 2057889 D Employee Stock Option (right to buy) 1.09 2025-09-18 4 M 0 1867496 0.0 D 2028-08-03 Common Stock 1867496 3254155 D Represents the sale of shares pursuant to a "sell-to-cover" transaction, with shares sold to cover the exercise price and satisfy applicable tax withholding obligations in connection with the exercise of stock options previously granted to the reporting person. The price reported in column 4 is a weighted average price of the aggregate number of shares. These shares were sold in multiple transactions in bulk at prices ranging from $47.7100 to $48.7000, inclusive. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote. The price reported in column 4 is a weighted average price of the aggregate number of shares. These shares were sold in multiple transactions in bulk at prices ranging from $48.7100 to $48.9300, inclusive. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote. The stock option was granted on August 3, 2018, and had a vesting commencement date of May 25, 2018. 1/4 of the shares subject to the stock option vest on the one year anniversary of the vesting commencement date, and 1/48 of the shares subject to the stock option vest on a monthly basis each month thereafter, subject, in each case, to the reporting person's continued service relationship through each applicable vesting date. By: /s/ Arjun Kampani, as Attorney-in-Fact For: Adam C. Spice 2025-09-22