X0306 4 2018-02-20 0 0001018963 ALLEGHENY TECHNOLOGIES INC ATI 0001332656 Powers Elizabeth C 1000 SIX PPG PLACE PITTSBURGH PA 15222 0 1 0 0 Senior VP, CHRO Common Stock, $0.10 par value per share 2018-02-20 4 D 0 4936.064 0.00 D 54977.3389 D Common Stock, $0.10 par value per share 2018-02-20 4 A 0 8976 0.00 A 63953.3389 D Forfeiture of restricted shares, including accumulated dividends, granted under the 2015 Long-Term Shareholder Value Program. This amount includes 1,792.941062 shares of common stock that Ms. Powers owns in the Company's 401(k) Plan. Fluctuations in 401(k) share amounts reflect the Plan's unit reporting method. Ms. Powers holds approximately 1,397 units, which represent interests in the Company's stock fund. Award of restricted stock units, which are settled in shares of stock upon vesting. The award vests in three equal annual installments on each of the first three anniversaries of the grant date. /s/ Elliot S. Davis, Attorney-in-Fact for Elizabeth C. Powers 2018-02-22