X0306 4 2013-03-28 0 0000866121 ALLIANT TECHSYSTEMS INC ATK 0001188447 DEYOUNG MARK W 1300 WILSON BOULEVARD SUITE 400 ARLINGTON VA 22209 1 1 0 0 President and CEO Phantom Stock Units 2013-03-28 4 A 0 9.2187 72.43 A Common Stock 9.2187 2577 D Deferred Stock Units 2013-03-28 4 A 0 27.3137 72.43 A Common Stock 27.3137 7636 D These securities were acquired through the deemed reinvestment of dividend equivalents in the form of additional Phantom Stock Units credited to the reporting person's account under the Issuer's Nonqualified Deferred Compensation Plan (NQDCP). The Phantom Stock Units will be settled 100% in cash following the reporting person's termination of employment or such other date specified by the reporting person. NQDCP participants may reallocate amounts between this Phantom Stock Unit investment alternative and other investment accounts during a 10-day window period each quarter. 1-for-1. These securities were acquired through the deemed reinvestment of dividend equivalents in the form of additional Deferred Stock Units credited to the reporting person's account under the Issuer's NQDCP. The Deferred Stock Units will be settled 100% in shares of the Issuer's common stock following the reporting person's termination of employment or such other date specified by the reporting person under the terms of the NQDCP. Converts to common stock 1-for-1. /s/Mark W. DeYoung 2013-03-28