ATI

Shares sold pursuant to a 10b5-1 Trading Plan dated February 5, 2026, entered into for personal tax and estate planning purposes.

The price reported is a weighted average price. These shares were sold in multiple transactions at prices ranging from $184.07 to 185.02. The reporting person undertakes to provide to the Issuer, its security holders and the Staff of the SEC, upon request, full information regarding the number of shares sold at each specific price within the range reported.

Shares sold pursuant to a 10b5-1 Trading Plan dated February 5, 2026, entered into for personal tax and estate planning purposes.

The price reported is a weighted average price. These shares were sold in multiple transactions at prices ranging from $181.01 to $181.95. The reporting person undertakes to provide to the Issuer, its security holders and the Staff of the SEC, upon request, full information regarding the number of shares sold at each specific price within the range reported.

Shares sold pursuant to a 10b5-1 Trading Plan dated February 5, 2026, entered into for personal tax and estate planning purposes.

The price reported is a weighted average price. The shares were sold in multiple transactions at prices ranging from $180.83 to $181.87. The reporting person undertakes to provide to the Issuer, its security holders and the Staff of the SEC, upon request, full information regarding the number of shares sold at each specific price within the range reported.

Shares sold pursuant to a 10b5-1 Trading Plan dated February 5, 2026, entered into for personal tax and estate planning purposes.

The price reported is a weighted average price. The shares were sold in multiple transactions at prices ranging from $178.71 to $179.70. The reporting person undertakes to provide to the Issuer, its security holders and the Staff of the U.S. Securities and Exchange Commission (the "SEC"), upon request, full information regarding the number of shares sold at each specific price within the range reported.

Shares sold pursuant to a 10b5-1 Trading Plan dated February 5, 2026, entered into for personal tax and estate planning purposes.

The price reported is a weighted average price. These shares were sold in multiple transactions at prices ranging from $182.06 to $183.01. The reporting person undertakes to provide to the Issuer, its security holders and the Staff of the SEC, upon request, full information regarding the number of shares sold at each specific price within the range reported.

Shares sold pursuant to a 10b5-1 Trading Plan dated February 5, 2026, entered into for personal tax and estate planning purposes.

The price reported is a weighted average price. These shares were sold in multiple transactions at prices ranging from $183.07 to 184.06. The reporting person undertakes to provide to the Issuer, its security holders and the Staff of the SEC, upon request, full information regarding the number of shares sold at each specific price within the range reported.

Shares sold pursuant to a 10b5-1 Trading Plan dated February 5, 2026, entered into for personal tax and estate planning purposes.

The price reported is a weighted average price. The shares were sold in multiple transactions at prices ranging from $179.77 to $180.39. The reporting person undertakes to provide to the Issuer, its security holders and the Staff of the SEC, upon request, full information regarding the number of shares sold at each specific price within the range reported.

Shares withheld for payment of taxes on restricted stock units that vested by their terms on July 1, 2026.

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 July 1, 2026.

Shares sold pursuant to a 10b5-1 Trading Plan dated February 5, 2026, entered into for personal tax and estate planning purposes.

Shares sold pursuant to a 10b5-1 Trading Plan dated February 5, 2026, entered into for personal tax and estate planning purposes.

Shares sold pursuant to a 10b5-1 Trading Plan dated February 5, 2026, entered into for personal tax and estate planning purposes.

Shares sold pursuant to a 10b5-1 Trading Plan dated February 5, 2026, entered into for personal tax and estate planning purposes.

The price reported is a weighted average price. The shares were sold in multiple transactions at prices ranging from $179.41 to $180.27. The reporting person undertakes to provide to the Issuer, its security holders and the Staff of the SEC, upon request, full information regarding the number of shares sold at each specific price within the range reported.

Shares sold pursuant to a 10b5-1 Trading Plan dated February 5, 2026, entered into for personal tax and estate planning purposes.

The price reported is a weighted average price. These shares were sold in multiple transactions at prices ranging from $181.47 to $182.45. The reporting person undertakes to provide to the Issuer, its security holders and the Staff of the SEC, upon request, full information regarding the number of shares sold at each specific price within the range reported.

Shares sold pursuant to a 10b5-1 Trading Plan dated February 5, 2026, entered into for personal tax and estate planning purposes.

The price reported is a weighted average price. The shares were sold in multiple transactions at prices ranging from $178.42 to $179.40. The reporting person undertakes to provide to the Issuer, its security holders and the Staff of the SEC, upon request, full information regarding the number of shares sold at each specific price within the range reported.

Shares sold pursuant to a 10b5-1 Trading Plan dated February 5, 2026, entered into for personal tax and estate planning purposes.

The price reported is a weighted average price. The shares were sold in multiple transactions at prices ranging from $177.42 to $178.35. The reporting person undertakes to provide to the Issuer, its security holders and the Staff of the U.S. Securities and Exchange Commission (the "SEC"), upon request, full information regarding the number of shares sold at each specific price within the range reported.

Shares sold pursuant to a 10b5-1 Trading Plan dated February 5, 2026, entered into for personal tax and estate planning purposes.

The price reported is a weighted average price. These shares were sold in multiple transactions at prices ranging from $182.49 to 183.18. The reporting person undertakes to provide to the Issuer, its security holders and the Staff of the SEC, upon request, full information regarding the number of shares sold at each specific price within the range reported.

Shares sold pursuant to a 10b5-1 Trading Plan dated February 5, 2026, entered into for personal tax and estate planning purposes.

The price reported is a weighted average price. These shares were sold in multiple transactions at prices ranging from $180.45 to $181.26. The reporting person undertakes to provide to the Issuer, its security holders and the Staff of the SEC, upon request, full information regarding the number of shares sold at each specific price within the range reported.

Annual award of restricted stock granted under the Issuer's 2022 Incentive Plan as part of the Issuer's Director compensation program. The award vests on the first anniversary of the grant date.

Annual award granted under the Issuer's 2022 Incentive Plan as part of the Issuer's Director compensation program.

Annual award of restricted stock granted under the Issuer's 2022 Incentive Plan as part of the Issuer's Director compensation program. The award vests on the first anniversary of the grant date.

Annual award granted under the Issuer's 2022 Incentive Plan as part of the Issuer's Director compensation program.

Annual award of restricted stock granted under the Issuer's 2022 Incentive Plan as part of the Issuer's Director compensation program. The award vests on the first anniversary of the grant date.

Annual award granted under the Issuer's 2022 Incentive Plan as part of the Issuer's Director compensation program.

Annual award of restricted stock granted under the Issuer's 2022 Incentive Plan as part of the Issuer's Director compensation program. The award vests on the first anniversary of the grant date.

Annual award granted under the Issuer's 2022 Incentive Plan as part of the Issuer's Director compensation program.

Annual award of restricted stock granted under the Issuer's 2022 Incentive Plan as part of the Issuer's Director compensation program. The award vests on the first anniversary of the grant date.

Annual award granted under the Issuer's 2022 Incentive Plan as part of the Issuer's Director compensation program.

Annual award of restricted stock granted under the Issuer's 2022 Incentive Plan as part of the Issuer's Director compensation program. The award vests on the first anniversary of the grant date.

Annual award granted under the Issuer's 2022 Incentive Plan as part of the Issuer's Director compensation program.

Annual award of restricted stock granted under the Issuer's 2022 Incentive Plan as part of the Issuer's Director compensation program. The award vests on the first anniversary of the grant date.

Annual award granted under the Issuer's 2022 Incentive Plan as part of the Issuer's Director compensation program.

Annual award of restricted stock granted under the Issuer's 2022 Incentive Plan as part of the Issuer's Director compensation program. The award vests on the first anniversary of the grant date.

Annual award granted under the Issuer's 2022 Incentive Plan as part of the Issuer's Director compensation program.

Annual award of restricted stock granted under the Issuer's 2022 Incentive Plan as part of the Issuer's Director compensation program. The award vests on the first anniversary of the grant date.

Annual award granted under the Issuer's 2022 Incentive Plan as part of the Issuer's Director compensation program.

Shares sold pursuant to a 10b5-1 Trading Plan dated February 5, 2026, entered into for personal tax and estate planning purposes.

The price reported is a weighted average price. The shares were sold in multiple transactions at prices ranging from $155.78 to $156.76. The reporting person undertakes to provide to the Issuer, its security holders and the Staff of the SEC, upon request, full information regarding the number of shares sold at each specific price within the range reported.

Shares sold pursuant to a 10b5-1 Trading Plan dated February 5, 2026, entered into for personal tax and estate planning purposes.

The price reported is a weighted average price. The shares were sold in multiple transactions at prices ranging from $156.91 to $157.90. The reporting person undertakes to provide to the Issuer, its security holders and the Staff of the SEC, upon request, full information regarding the number of shares sold at each specific price within the range reported.

Shares sold pursuant to a 10b5-1 Trading Plan dated February 5, 2026, entered into for personal tax and estate planning purposes.

The price reported is a weighted average price. These shares were sold in multiple transactions at prices ranging from $158.94 to $159.84. The reporting person undertakes to provide to the Issuer, its security holders and the Staff of the SEC, upon request, full information regarding the number of shares sold at each specific price within the range reported.

Shares sold pursuant to a 10b5-1 Trading Plan dated February 5, 2026, entered into for personal tax and estate planning purposes.

The price reported is a weighted average price. These shares were sold in multiple transactions at prices ranging from $160.99 to 161.38. The reporting person undertakes to provide to the Issuer, its security holders and the Staff of the SEC, upon request, full information regarding the number of shares sold at each specific price within the range reported.

Shares sold pursuant to a 10b5-1 Trading Plan dated February 5, 2026, entered into for personal tax and estate planning purposes.

The price reported is a weighted average price. These shares were sold in multiple transactions at prices ranging from $159.99 to 160.98. The reporting person undertakes to provide to the Issuer, its security holders and the Staff of the SEC, upon request, full information regarding the number of shares sold at each specific price within the range reported.

Shares sold pursuant to a 10b5-1 Trading Plan dated February 5, 2026, entered into for personal tax and estate planning purposes.

The price reported is a weighted average price. The shares were sold in multiple transactions at prices ranging from $153.82 to $154.65. The reporting person undertakes to provide to the Issuer, its security holders and the Staff of the U.S. Securities and Exchange Commission (the "SEC"), upon request, full information regarding the number of shares sold at each specific price within the range reported.

Shares sold pursuant to a 10b5-1 Trading Plan dated February 5, 2026, entered into for personal tax and estate planning purposes.

The price reported is a weighted average price. These shares were sold in multiple transactions at prices ranging from $157.91 to $158.88. The reporting person undertakes to provide to the Issuer, its security holders and the Staff of the SEC, upon request, full information regarding the number of shares sold at each specific price within the range reported.

Shares withheld for payment of taxes on restricted stock units awarded on March 20, 2024. On third of such restricted stock units vested by their terms on March 20, 2026.

Represents the average of the high and low trading prices for on share of the Issuer's Common Stock on the New York Stock Exchange on March 20, 2026.

The price reported is a weighted average price. The shares were sold in multiple transactions at prices ranging from $152.77 to to $153.53. The reporting person undertakes to provide to the Issuer, its security holders and the Staff of the U.S. Securities and Exchange Commission (the "SEC"), upon request, full information regarding the number of shares sold at each specific price within the range reported.

The price reported is a weighted average price. The shares were sold in multiple transactions at prices ranging from $154.31 to to $154.81. The reporting person undertakes to provide to the Issuer, its security holders and the Staff of the SEC, upon request, full information regarding the number of shares sold at each specific price within the range reported.

Shares withheld for the payment of taxes on restricted stock units awarded on March 1, 2024. One-third of such restricted stock units vested by their terms on March 1, 2026.

Represents the average of the high and low trading prices of one share of the Issuer's Common Stock on the New York Stock Exchange on March 2, 2026.

Shares sold pursuant to a 10b5-1 Trading Plan dated August 15, 2025, entered into for personal tax and estate planning purposes.

The price reported is a weighted average price. The shares were sold in multiple transactions at prices ranging from $143.45 to $144.45. The reporting person undertakes to provide to the Issuer, its security holders and the Staff of the U.S. Securities and Exchange Commission (the "SEC"), upon request, full information regarding the number of shares sold at each specific price within the range reported.

Shares sold pursuant to a 10b5-1 Trading Plan dated August 15, 2025, entered into for personal tax and estate planning purposes.

The price reported is a weighted average price. The shares were sold in multiple transactions at prices ranging from $144.48 to $145.47. The reporting person undertakes to provide to the Issuer, its security holders and the Staff of the SEC, upon request, full information regarding the number of shares sold at each specific price within the range reported.

Shares sold pursuant to a 10b5-1 Trading Plan dated August 15, 2025, entered into for personal tax and estate planning purposes.

The price reported is a weighted average price. The shares were sold in multiple transactions at prices ranging from $145.51 to $146.51. The reporting person undertakes to provide to the Issuer, its security holders and the Staff of the SEC, upon request, full information regarding the number of shares sold at each specific price within the range reported.

Shares donated to one or more charitable organizations as a bona fide gift.

Shares sold pursuant to a 10b5-1 Trading Plan dated August 15, 2025, entered into for personal tax and estate planning purposes.

The price reported is a weighted average price. These shares were sold in multiple transactions at prices ranging from $146.52 to $146.88, The reporting person undertakes to provide to the Issuer, its security holders and the Staff of the U. S. Securities and Exchange Commission (the "SEC"), upon request, full information regarding the number of shares sold at each specific price within the range reported.

Shares withheld for payment of taxes on restricted stock units awarded in 2023, 2024 and 2025. One third of each such award vested by the terms thereof on January 5, 2026.

Represents the average of the high and low trading prices for one share of the Issuer's Common Stock on the NYSE on January 5, 2026.

Settlement of one-half of certain Performance Stock Units awarded in 2022 ("2022 Breakout Performance Units"), each of which represented a contingent right to receive shares of the Issuer's Common Stock if the Issuer's Common Stock achieved specified target market prices (based on a 20-trading day average) on the New York Stock Exchange ("NYSE") for at least 20 consecutive trading days (the "20-day Average Market Price") prior to December 31, 2025, up to a maximum of three shares per Unit. The shares underlying one-half of the 2022 Breakout Performance Units became payable as of January 5, 2026 following certification of the Issuer's achievement of the relevant performance criteria by the Compensation and Leadership Development Committee of the Company's Board of Directors (the "CLDC"). The remaining half of the 2022 Breakout Performance Units are scheduled by their terms to become payable in early 2027.

Settlement of one-half of certain Performance Stock Units awarded in 2022 ("2022 Breakout Performance Units"), each of which represented a contingent right to receive shares of the Issuer's Common Stock if the Issuer's Common Stock achieved specified target market prices (based on a 20-trading day average) on the New York Stock Exchange ("NYSE") for at least 20 consecutive trading days (the "20-day Average Market Price") prior to December 31, 2025, up to a maximum of three shares per Unit. The shares underlying one-half of the 2022 Breakout Performance Units became payable as of January 5, 2026 following certification of the Issuer's achievement of the relevant performance criteria by the Compensation and Leadership Development Committee of the Company's Board of Directors (the "CLDC"). The remaining half of the 2022 Breakout Performance Units are scheduled by their terms to become payable in early 2027.

Shares withheld for the payment of taxes in connection with the settlement of 2022 Breakout Performance Units.

Represents the average of the high and low trading prices for one share of the Issuer's Common Stock on the NYSE on January 5, 2026.

Settlement of one-half of certain Performance Stock Units awarded in 2022 ("2022 Breakout Performance Units"), each of which represented a contingent right to receive shares of the Issuer's Common Stock if the Issuer's Common Stock achieved specified target market prices (based on a 20-trading day average) on the New York Stock Exchange ("NYSE") for at least 20 consecutive trading days (the "20-day Average Market Price") prior to December 31, 2025, up to a maximum of three shares per Unit. The shares underlying one-half of the 2022 Breakout Performance Units became payable as of January 5, 2026 following certification of the Issuer's achievement of the relevant performance criteria by the Compensation and Leadership Development Committee of the Company's Board of Directors (the "CLDC"). The remaining half of the 2022 Breakout Performance Units are scheduled by their terms to become payable in early 2027.