X0306 4 2013-05-14 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 Common Stock 2013-05-14 4 A 0 5563 0 A 62366 D Common Stock 2013-05-14 4 F 0 1813 76.64 D 60553 D Common Stock 2013-05-14 4 A 0 57 0 A 60610 D Common Stock 2013-05-14 4 F 0 57 76.64 D 60553 D Common Stock 1261 I By 401(k) Plan Deferred Stock Units 2013-05-14 4 A 0 2327 0 A Common Stock 2327 9963 D Shares acquired represent payment of a Performance Share Award (PSA) under the 2005 Stock Incentive Plan, and shares disposed represent shares withheld from the PSA to pay withholding taxes. 40,954 of these shares are subject to certain restrictions including possible forfeiture applicable to restricted stock issued under the Issuer's 2005 Stock Incentive Plan. Shares simultaneously acquired and disposed represent shares withheld to pay Medicare taxes in connection with the deferral of a portion of performance shares earned under the PSA as permitted by the Issuer's Nonqualified Deferred Compensation Plan (NQDCP) (reported in Table II of this Form). Based on a plan statement dated March 31, 2013. The Deferred Stock Units were credited to the reporting person's account under the Issuer's NQDCP in lieu of a payment by the Issuer of performance shares under the Issuer's 2005 Stock Incentive Plan. The number of units credited to the reporting person's account was determined on a 1-for-1 basis equal to the number of shares of common stock that would have been paid, reduced by the number of shares having a value equal to the Issuer's Medicare tax withholding obligation as a result of the deferral of the payment of the shares. The 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. /s/Mark W. DeYoung 2013-05-16