X0306 4 2019-05-01 0 0000917273 RAMBUS INC RMBS 0001318086 Higashi Emiko 1050 ENTERPRISE WAY, SUITE 700 SUNNYVALE CA 94089 1 0 0 0 Common Stock 2019-05-01 4 A 0 14156 0.00 A 40058 D The shares are represented by restricted stock units, or RSUs, all of which vest May 1, 2020 or the first business day thereafter. Each RSU represents the contingent right to receive one share of RMBS common stock. /s/ Kirk Williams, by power of attorney 2019-05-02