X0306 4 2017-11-20 0 0001666134 BLACKLINE, INC. BL 0001688128 Spanicciati Mario 21300 VICTORY BLVD., 12TH FLOOR WOODLAND HILLS CA 91367 1 1 0 0 Chief Marketing Officer Common Stock 2017-11-20 4 S 0 12750 36.79 D 3167446 I Spanicciati Family 2013 Irrevocable Trust Common Stock 848928 I Spanicciati Family 2013 Dynasty Trust The sale transaction reported on this Form 4 was effected pursuant to a Rule 10b5-1 trading plan adapted by the Reporting Person on March 14, 2017. The sale price represents the weighted average price of the shares sold ranging from $36.54 to $37.39 per share. Upon request by the Commission staff, the Issuer or a security holder of the Issuer, the Reporting Person will provide full information regarding the number of shares sold at each separate price within the range set forth in this Form 4. /s/ Karole Morgan-Prager, Attorney-in-Fact 2017-11-20