X0306 4 2016-02-04 0 0000866121 ORBITAL ATK, INC. OA 0001035150 MCCABE THOMAS E C/O ORBITAL ATK, INC. 45101 WARP DRIVE DULLES VA 20166 0 1 0 0 Senior VP and General Counsel Common Stock 2016-02-04 4 S 0 1461 88.8664 D 7904 D The sales reported in this Form 4 were effected pursuant to a Rule 10b5-1 trading plan. This transaction was executed in multiple trades at prices ranging from $88.76 to $89.05. The price reported above reflects the weighted average sale price. The reporting person hereby undertakes to provide upon request to the SEC staff, the issuer or a security holder of the issuer, full information regarding the number of shares and prices at which the transaction was effected. /s/ Richard N. Osborne, Attorney-in-Fact 2016-02-05