X0306 4 2018-02-13 0 0001590750 MIRAGEN THERAPEUTICS, INC. MGEN 0001693127 Marshall William Stuart C/O MIRAGEN THERAPEUTICS, INC. 6200 LOOKOUT ROAD BOULDER CO 80301 1 1 0 0 President & CEO Common Stock 2018-02-13 4 M 0 115818 0.57 A 265646 D Stock Option (right to buy) 0.57 2018-02-13 4 M 0 115818 0.00 D 2018-07-30 Common Stock 115818 0 D This filing relates to the exercise of vested options to purchase the Issuer's common stock granted to the Reporting Person under one of the Issuer's equity incentive plans. None of the shares of common stock received upon exercise of the option were sold by the Reporting Person and all such shares are subject to a lock-up agreement between the Reporting Person and certain underwriters. The option is fully vested and exercisable. The option expires ten years after the date of grant. /s/ Kassendra Galindo, as Attorney-in-Fact for William S. Marshall 2018-02-15