X0306 4 2015-05-13 0 0000866121 ORBITAL ATK, INC. OA 0001045853 THOMPSON DAVID W C/O ORBITAL ATK 45101 WARP DRIVE DULLES VA 20166 1 1 0 0 President and CEO Common Stock 2015-05-13 5 G 0 200 0 D 6022 I By Trust Common Stock 2015-08-13 5 G 0 300 0 D 5722 I By Trust Common Stock 2015-09-03 5 G 0 100 0 D 5622 I By Trust Common Stock 2015-10-07 5 G 0 500 0 D 5122 I By Trust Common Stock 2015-10-28 5 G 0 200 0 D 4922 I By Trust Common Stock 2015-11-17 5 G 0 2000 0 D 98860 D Common Stock 10147 I By Spouse Common Stock 2306.8219 I By 401(k) Plan This total reflects previously-reported gifts of 500 shares on 4/14/2015, 400 shares on 5/22/2015 and 150 shares on 6/24/2015. After those gifts were reported, the reporting person filed an amendment to a Form 4 dated 2/9/2015 to clarify that 7,272 shares previously included in his direct ownership total were actually indirectly beneficially owned by him through his trust. Those three previously-reported gifts were made from the trust and not the reporting person's directly-owned shares. Based on a plan statement dated September 30, 2015. /s/ Richard N. Osborne, Attorney-in-Fact 2015-12-17