X0306 4 2020-04-01 0 0001595974 RUBICON PROJECT, INC. RUBI 0001350876 Knopper Douglas S C/O THE RUBICON PROJECT, INC. 12181 BLUFF CREEK DRIVE, 4TH FLOOR LOS ANGELES CA 90094 1 0 0 0 Common Stock 2020-04-01 4 A 0 102884 A 102884 D Received on April 1, 2020, the effective date (the "Effective Date") of the merger between the Issuer and Telaria, Inc. ("Telaria") pursuant to that certain Agreement and Plan of Merger, dated as of December 19, 2019 (the "Merger Agreement") at a rate of 1.082 shares of the Issuer's common stock for (i) each share of previously held Telaria common stock, and (ii) each share underlying previously held Telaria restricted stock units that vested on the Effective Date. /s/ Aaron Saltz, Attorney-in-Fact 2020-04-03