X0306 4 2021-02-22 0 0001018963 ALLEGHENY TECHNOLOGIES INC ATI 0001549592 Kramer Kevin B 1000 SIX PPG PLACE PITTSBURGH PA 15222 0 1 0 0 Sr. VP, CCMO Common Stock, par value $0.10 per share 2021-02-22 4 F 0 1732 19.89 D 168149.3608 D Shares withheld for payment of taxes on restricted stock units awarded on February 20, 2018. One-third of such restricted stock units vested by their terms on February 22, 2021. This amount includes 1,801.9487 shares of common stock that Mr. Kramer owns in the Company's 401(k) Plan. Fluctuations in 401(k) share amounts reflect the Plan's unit reporting method. Mr. Kramer holds approximately 1,512 units, which represent interests in the Company's stock fund. /s/ Elliot S. Davis, Attorney-in-Fact for Kevin B. Kramer 2021-02-24