X0609 4 2026-05-07 0001666134 BLACKLINE, INC. BL 0001854839 Whye Barbara false 21300 VICTORY BLVD., 12TH FLOOR WOODLAND HILLS CA 91367 1 0 Common Stock 2026-05-07 4 A 0 6416 0 A 16969 D Reflects an automatic annual restricted stock unit ("RSU") award pursuant to the Issuer's Outside Director Compensation Policy. The reported securities awarded on May 7, 2026 (the "Award Date") represent RSUs which vest in full upon the earlier of the one (1) year anniversary of the Award Date or the day prior to the Issuer's next annual meeting of the stockholders and in each case subject to the Reporting Person's continued service on the Issuer's board of directors through each vesting date. /s/ Karole Morgan-Prager, Attorney-in-Fact 2026-05-08