X0306 4 2019-02-27 0 0001018963 ALLEGHENY TECHNOLOGIES INC ATI 0001200244 HARSHMAN RICHARD J 1000 SIX PPG PLACE PITTSBURGH PA 15222-5479 1 1 0 0 Executive Chairman Common Stock, par value $0.10 per share 2019-02-27 4 F 0 11193 29.255 D 482372.7688 D Common Stock, par value $0.10 per share 2019-02-28 4 M 0 78742 28.92 A 561114.7688 D Common Stock, par value $0.10 per share 2019-02-28 4 F 0 34474 28.92 D 526640.7688 D Common Stock, par value $0.10 per share 2019-02-28 4 S 0 10780 29.13 D 515860.7688 D Shares withheld for payment of taxes on performance/restricted stock granted in 2014 that vested on February 27, 2019. Represents the average of the high and low trading prices for one share of the Issuer's common stock on the New York Stock Exchange on February 27, 2019. This amount includes 25,687 shares of common stock owned indirectly by Mr. Harshman's wife. The reporting person disclaims beneficial ownership of the shares held directly or indirectly by his spouse, and this report shall not be deemed an admission that the reporting person is the beneficial owner of such shares for the purposes of Section 16 or for any other purpose. Settlement of performance-vested restricted stock units that were granted in 2016, the vesting of which was contingent upon the Issuer's achievement of specified performance criteria during the period from January 1, 2016 through December 31, 2018 (the "2016-2018 PSUs"). The Issuer's partial achievement of such performance criteria was certified, and a corresponding portion of the shares underlying the 2016-2018 PSUs became payable, as of February 28, 2019. Represents the average of the high and low trading prices for one share of the Issuer's common stock on the New York Stock Exchange on February 28, 2019. Shares withheld for payment of taxes in connection with the February 28, 2019 settlement of the 2016-2018 PSUs. Shares sold pursuant to a 10b5-1 Trading Plan. /s/ Elliot S. Davis, Attorney-in-Fact for Richard J. Harshman 2019-03-01