X0306 4 2022-09-09 0 0001819994 Rocket Lab USA, Inc. RKLB 0001045849 GRIFFIN MICHAEL D C/O ROCKET LAB USA, INC. 3881 MCGOWEN STREET LONG BEACH CA 90808 1 0 0 0 Common Stock 2022-09-09 4 J 0 456190 0.00 D 190156 D Common Stock 2022-09-09 4 J 0 456190 0.00 D 456190 I By LogiQ, Inc Common Stock 2022-09-09 4 S 0 456190 5.62 D 0 I By LogiQ, Inc The reporting person transferred these shares to LogiQ, Inc., a corporation controlled by the reporting person and in which the reporting person holds a 50% economic interest. The reporting person disclaims beneficial ownership of any securities held by LogiQ, Inc. except to the extent of their pecuniary interest therein. The price reported in column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $5.56 to $5.665, 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 (2) to this Form 4. /s/ Arjun Kampani as Attorney-in-Fact for Michael D. Griffin 2022-09-13