X0206 3 2016-10-27 1 0001666134 BLACKLINE, INC. BL 0001297231 Brennan John C/O SILVER LAKE 2775 SAND HILL ROAD, SUITE 100 MENLO PARK CA 94025 1 0 0 0 Exhibit 24.1 - Power of Attorney Mr. Brennan is a Managing Director at Silver Lake Sumeru and is a member of the board of directors of BlackLine, Inc. (the "Issuer"). Certain affiliates of Silver Lake Sumeru have filed a separate Form 3 reporting securities of the Issuer that they may be deemed to beneficially own. Mr. Brennan disclaims beneficial ownership of any securities of the Issuer that may be deemed to be beneficially owned by affiliates of Silver Lake Sumeru. /s/ John Brennan 2016-10-27