X0306 4 2021-02-01 0 0000917273 RAMBUS INC RMBS 0001341984 Seraphin Luc C/O RAMBUS INC. 4453 NORTH FIRST STREET, SUITE 100 SAN JOSE CA 95134 1 1 0 0 President and CEO Common Stock 2021-02-01 4 F 0 21162 19.52 D 186849 D Common Stock 2021-02-01 4 A 0 15387 0.00 A 202236 D Common Stock 2021-02-01 4 A 0 73770 0.00 A 276006 D Common Stock 2021-02-02 4 S 0 36366 19.3408 D 239640 D The shares were withheld to cover the Reporting Person's tax liability in connection with the vesting of restricted stock units, or RSUs. The shares are represented by performance restricted stock units, or PRSUs, all of which vest on February 1, 2021 based upon assessed achievement of the Company's performance metrics and continued service to the Company through the vesting date. Each PRSU represents a contingent right to receive one share of RMBS common stock. The shares are represented by RSUs which vest in four equal annual installments beginning on February 1, 2022 or the first business trading day thereafter. Each RSU represents a contingent right to receive one share of RMBS common stock. The sale reported in this Form 4 was effected pursuant to a Rule 10b5-1 trading plan adopted on February 21, 2020. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $18.31 to $19.75, 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. s/ Keith Jones, by power of attorney 2021-02-03