ATI

SEC source: 0001209191-22-002210 · doc4.xml · derivative · entry 3

WETHERBEE ROBERT S · CIK 0001572385 · Director · Board Chair, President and CEO

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 128,205

Underlying: Common Stock · 128,205 shares

Expires 2025-12-31

F5 · derivative.exercise_price: Each Performance Stock Unit ("PSU") represents a contingent right to receive one share of the Issuer's Common Stock if the Issuer's Common Stock achieves a specified target market price (based on a 20-trading day average) on the NYSE for at least 20 consecutive trading days ("20-Day Average Market Price") prior to December 31, 2025. Each PSU may result in the right to receive additional shares of the Issuer's Common Stock, up to a maximum of three shares per PSU, to the extent that the Issuer's Common Stock achieves 20-Day Average Market Prices at specified levels in excess of the target market price prior to December 31, 2025. Vested shares, if any, generally are payable in two equal installments in early 2026 and early 2027.

F4 · price: Awarded under ATI's 2020 Incentive Plan.

F5 · derivative.exercise_date: Each Performance Stock Unit ("PSU") represents a contingent right to receive one share of the Issuer's Common Stock if the Issuer's Common Stock achieves a specified target market price (based on a 20-trading day average) on the NYSE for at least 20 consecutive trading days ("20-Day Average Market Price") prior to December 31, 2025. Each PSU may result in the right to receive additional shares of the Issuer's Common Stock, up to a maximum of three shares per PSU, to the extent that the Issuer's Common Stock achieves 20-Day Average Market Prices at specified levels in excess of the target market price prior to December 31, 2025. Vested shares, if any, generally are payable in two equal installments in early 2026 and early 2027.

F5 · derivative.expiration_date: Each Performance Stock Unit ("PSU") represents a contingent right to receive one share of the Issuer's Common Stock if the Issuer's Common Stock achieves a specified target market price (based on a 20-trading day average) on the NYSE for at least 20 consecutive trading days ("20-Day Average Market Price") prior to December 31, 2025. Each PSU may result in the right to receive additional shares of the Issuer's Common Stock, up to a maximum of three shares per PSU, to the extent that the Issuer's Common Stock achieves 20-Day Average Market Prices at specified levels in excess of the target market price prior to December 31, 2025. Vested shares, if any, generally are payable in two equal installments in early 2026 and early 2027.

SEC source: 0001209191-22-002210 · doc4.xml · nonDerivative · entry 2

WETHERBEE ROBERT S · CIK 0001572385 · Director · Board Chair, President and CEO

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 383,489.3409

F3 · shares: 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.

F4 · price: Awarded under ATI's 2020 Incentive Plan.

SEC source: 0001209191-22-002210 · doc4.xml · nonDerivative · entry 1

WETHERBEE ROBERT S · CIK 0001572385 · Director · Board Chair, President and CEO

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 287,881.3409

F1 · shares: Shares withheld for payment of taxes on restricted stock units awarded on January 4, 2021. One-third of such restricted stock units vested by their terms on January 4, 2022.

F2 · price: 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 ("NYSE") on January 4, 2022.

SEC source: 0001209191-22-002209 · doc4.xml · derivative · entry 3

Schwartz Karl D · CIK 0001498160 · VP, Controller & CAO

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 5,128

Underlying: Common Stock · 5,128 shares

Expires 2025-12-31

F6 · derivative.exercise_price: Each Performance Stock Unit ("PSU") represents a contingent right to receive one share of the Issuer's Common Stock if the Issuer's Common Stock achieves a specified target market price (based on a 20-trading day average) on the NYSE for at least 20 consecutive trading days ("20-Day Average Market Price") prior to December 31, 2025. Each PSU may result in the right to receive additional shares of the Issuer's Common Stock, up to a maximum of three shares per PSU, to the extent that the Issuer's Common Stock achieves 20-Day Average Market Prices at specified levels in excess of the target market price prior to December 31, 2025. Vested shares, if any, generally are payable in two equal installments in early 2026 and early 2027.

F5 · price: Awarded under ATI's 2020 Incentive Plan.

F6 · derivative.exercise_date: Each Performance Stock Unit ("PSU") represents a contingent right to receive one share of the Issuer's Common Stock if the Issuer's Common Stock achieves a specified target market price (based on a 20-trading day average) on the NYSE for at least 20 consecutive trading days ("20-Day Average Market Price") prior to December 31, 2025. Each PSU may result in the right to receive additional shares of the Issuer's Common Stock, up to a maximum of three shares per PSU, to the extent that the Issuer's Common Stock achieves 20-Day Average Market Prices at specified levels in excess of the target market price prior to December 31, 2025. Vested shares, if any, generally are payable in two equal installments in early 2026 and early 2027.

F6 · derivative.expiration_date: Each Performance Stock Unit ("PSU") represents a contingent right to receive one share of the Issuer's Common Stock if the Issuer's Common Stock achieves a specified target market price (based on a 20-trading day average) on the NYSE for at least 20 consecutive trading days ("20-Day Average Market Price") prior to December 31, 2025. Each PSU may result in the right to receive additional shares of the Issuer's Common Stock, up to a maximum of three shares per PSU, to the extent that the Issuer's Common Stock achieves 20-Day Average Market Prices at specified levels in excess of the target market price prior to December 31, 2025. Vested shares, if any, generally are payable in two equal installments in early 2026 and early 2027.

SEC source: 0001209191-22-002209 · doc4.xml · nonDerivative · entry 2

Schwartz Karl D · CIK 0001498160 · VP, Controller & CAO

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 68,509.0107

F4 · shares: 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.

F5 · price: Awarded under ATI's 2020 Incentive Plan.

F3 · balance_after: This amount includes 6,195.9567 shares of common stock that Mr. Schwartz owns in the Company's 401(k) Plan. Fluctuations in 401(k) share amounts reflect the Plan's unit reporting method. Mr. Schwartz holds approximately 5,191 units, which represent interests in the Company's stock fund.

SEC source: 0001209191-22-002209 · doc4.xml · nonDerivative · entry 1

Schwartz Karl D · CIK 0001498160 · VP, Controller & CAO

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 59,926.0107

F1 · shares: Shares withheld for payment of taxes on restricted stock units awarded on January 4, 2021. One-third of such restricted stock units vested by their terms on January 4, 2022.

F2 · price: 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 ("NYSE") on January 4, 2022.

F3 · balance_after: This amount includes 6,195.9567 shares of common stock that Mr. Schwartz owns in the Company's 401(k) Plan. Fluctuations in 401(k) share amounts reflect the Plan's unit reporting method. Mr. Schwartz holds approximately 5,191 units, which represent interests in the Company's stock fund.

SEC source: 0001209191-22-002208 · doc4.xml · derivative · entry 3

NEWMAN DONALD P · CIK 0001282236 · EVP and CFO

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 61,538

Underlying: Common Stock · 61,538 shares

Expires 2025-12-31

F5 · derivative.exercise_price: Each Performance Stock Unit ("PSU") represents a contingent right to receive one share of the Issuer's Common Stock if the Issuer's Common Stock achieves a specified target market price (based on a 20-trading day average) on the NYSE for at least 20 consecutive trading days ("20-Day Average Market Price") prior to December 31, 2025. Each PSU may result in the right to receive additional shares of the Issuer's Common Stock, up to a maximum of three shares per PSU, to the extent that the Issuer's Common Stock achieves 20-Day Average Market Prices at specified levels in excess of the target market price prior to December 31, 2025. Vested shares, if any, generally are payable in two equal installments in early 2026 and early 2027.

F4 · price: Awarded under ATI's 2020 Incentive Plan.

F5 · derivative.exercise_date: Each Performance Stock Unit ("PSU") represents a contingent right to receive one share of the Issuer's Common Stock if the Issuer's Common Stock achieves a specified target market price (based on a 20-trading day average) on the NYSE for at least 20 consecutive trading days ("20-Day Average Market Price") prior to December 31, 2025. Each PSU may result in the right to receive additional shares of the Issuer's Common Stock, up to a maximum of three shares per PSU, to the extent that the Issuer's Common Stock achieves 20-Day Average Market Prices at specified levels in excess of the target market price prior to December 31, 2025. Vested shares, if any, generally are payable in two equal installments in early 2026 and early 2027.

F5 · derivative.expiration_date: Each Performance Stock Unit ("PSU") represents a contingent right to receive one share of the Issuer's Common Stock if the Issuer's Common Stock achieves a specified target market price (based on a 20-trading day average) on the NYSE for at least 20 consecutive trading days ("20-Day Average Market Price") prior to December 31, 2025. Each PSU may result in the right to receive additional shares of the Issuer's Common Stock, up to a maximum of three shares per PSU, to the extent that the Issuer's Common Stock achieves 20-Day Average Market Prices at specified levels in excess of the target market price prior to December 31, 2025. Vested shares, if any, generally are payable in two equal installments in early 2026 and early 2027.

SEC source: 0001209191-22-002208 · doc4.xml · nonDerivative · entry 2

NEWMAN DONALD P · CIK 0001282236 · EVP and CFO

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 150,029

F3 · shares: 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.

F4 · price: Awarded under ATI's 2020 Incentive Plan.

SEC source: 0001209191-22-002208 · doc4.xml · nonDerivative · entry 1

NEWMAN DONALD P · CIK 0001282236 · EVP and CFO

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 118,479

F1 · shares: Shares withheld for payment of taxes on restricted stock units awarded on January 4, 2021. One-third of such restricted stock units vested by their terms on January 4, 2022.

F2 · price: 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 ("NYSE") on January 4, 2022.

SEC source: 0001209191-22-002206 · doc4.xml · derivative · entry 3

Harris Timothy J · CIK 0001776844 · Senior VP and CDIO

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 51,282

Underlying: Common Stock · 51,282 shares

Expires 2025-12-31

F5 · derivative.exercise_price: Each Performance Stock Unit ("PSU") represents a contingent right to receive one share of the Issuer's Common Stock if the Issuer's Common Stock achieves a specified target market price (based on a 20-trading day average) on the NYSE for at least 20 consecutive trading days ("20-Day Average Market Price") prior to December 31, 2025. Each PSU may result in the right to receive additional shares of the Issuer's Common Stock, up to a maximum of three shares per PSU, to the extent that the Issuer's Common Stock achieves 20-Day Average Market Prices at specified levels in excess of the target market price prior to December 31, 2025. Vested shares, if any, generally are payable in two equal installments in early 2026 and early 2027.

F4 · price: Awarded under ATI's 2020 Incentive Plan.

F5 · derivative.exercise_date: Each Performance Stock Unit ("PSU") represents a contingent right to receive one share of the Issuer's Common Stock if the Issuer's Common Stock achieves a specified target market price (based on a 20-trading day average) on the NYSE for at least 20 consecutive trading days ("20-Day Average Market Price") prior to December 31, 2025. Each PSU may result in the right to receive additional shares of the Issuer's Common Stock, up to a maximum of three shares per PSU, to the extent that the Issuer's Common Stock achieves 20-Day Average Market Prices at specified levels in excess of the target market price prior to December 31, 2025. Vested shares, if any, generally are payable in two equal installments in early 2026 and early 2027.

F5 · derivative.expiration_date: Each Performance Stock Unit ("PSU") represents a contingent right to receive one share of the Issuer's Common Stock if the Issuer's Common Stock achieves a specified target market price (based on a 20-trading day average) on the NYSE for at least 20 consecutive trading days ("20-Day Average Market Price") prior to December 31, 2025. Each PSU may result in the right to receive additional shares of the Issuer's Common Stock, up to a maximum of three shares per PSU, to the extent that the Issuer's Common Stock achieves 20-Day Average Market Prices at specified levels in excess of the target market price prior to December 31, 2025. Vested shares, if any, generally are payable in two equal installments in early 2026 and early 2027.

SEC source: 0001209191-22-002206 · doc4.xml · nonDerivative · entry 2

Harris Timothy J · CIK 0001776844 · Senior VP and CDIO

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 86,800

F3 · shares: 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.

F4 · price: Awarded under ATI's 2020 Incentive Plan.

SEC source: 0001209191-22-002206 · doc4.xml · nonDerivative · entry 1

Harris Timothy J · CIK 0001776844 · Senior VP and CDIO

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 64,333

F1 · shares: Shares withheld for payment of taxes on restricted stock units awarded on January 4, 2021. One-third of such restricted stock units vested by their terms on January 4, 2022.

F2 · price: 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 ("NYSE") on January 4, 2022.

SEC source: 0001209191-22-002205 · doc4.xml · derivative · entry 3

Fields Kimberly A · CIK 0001773072 · EVP & COO

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 71,795

Underlying: Common Stock · 71,795 shares

Expires 2025-12-31

F5 · derivative.exercise_price: Each Performance Stock Unit ("PSU") represents a contingent right to receive one share of the Issuer's Common Stock if the Issuer's Common Stock achieves a specified target market price (based on a 20-trading day average) on the NYSE for at least 20 consecutive trading days ("20-Day Average Market Price") prior to December 31, 2025. Each PSU may result in the right to receive additional shares of the Issuer's Common Stock, up to a maximum of three shares per PSU, to the extent that the Issuer's Common Stock achieves 20-Day Average Market Prices at specified levels in excess of the target market price prior to December 31, 2025. Vested shares, if any, generally are payable in two equal installments in early 2026 and early 2027.

F4 · price: Awarded under ATI's 2020 Incentive Plan.

F5 · derivative.exercise_date: Each Performance Stock Unit ("PSU") represents a contingent right to receive one share of the Issuer's Common Stock if the Issuer's Common Stock achieves a specified target market price (based on a 20-trading day average) on the NYSE for at least 20 consecutive trading days ("20-Day Average Market Price") prior to December 31, 2025. Each PSU may result in the right to receive additional shares of the Issuer's Common Stock, up to a maximum of three shares per PSU, to the extent that the Issuer's Common Stock achieves 20-Day Average Market Prices at specified levels in excess of the target market price prior to December 31, 2025. Vested shares, if any, generally are payable in two equal installments in early 2026 and early 2027.

F5 · derivative.expiration_date: Each Performance Stock Unit ("PSU") represents a contingent right to receive one share of the Issuer's Common Stock if the Issuer's Common Stock achieves a specified target market price (based on a 20-trading day average) on the NYSE for at least 20 consecutive trading days ("20-Day Average Market Price") prior to December 31, 2025. Each PSU may result in the right to receive additional shares of the Issuer's Common Stock, up to a maximum of three shares per PSU, to the extent that the Issuer's Common Stock achieves 20-Day Average Market Prices at specified levels in excess of the target market price prior to December 31, 2025. Vested shares, if any, generally are payable in two equal installments in early 2026 and early 2027.

SEC source: 0001209191-22-002205 · doc4.xml · nonDerivative · entry 2

Fields Kimberly A · CIK 0001773072 · EVP & COO

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 131,261

F3 · shares: 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.

F4 · price: Awarded under ATI's 2020 Incentive Plan.

SEC source: 0001209191-22-002205 · doc4.xml · nonDerivative · entry 1

Fields Kimberly A · CIK 0001773072 · EVP & COO

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 91,823

F1 · shares: Shares withheld for payment of taxes on restricted stock units awarded on January 4, 2021. One-third of such restricted stock units vested by their terms on January 4, 2022.

F2 · price: 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 ("NYSE") on January 4, 2022.

SEC source: 0001209191-22-021134 · doc4a.xml · derivative · entry 3

WETHERBEE ROBERT S · CIK 0001572385 · Director · Board Chair, President and CEO

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 128,205

Underlying: Common Stock · 128,205 shares

Expires 2025-12-31

F5 · derivative.exercise_price: Each Performance Stock Unit ("PSU") represents a contingent right to receive one share of the Issuer's Common Stock if the Issuer's Common Stock achieves a specified target market price (based on a 20-trading day average) on the NYSE for at least 20 consecutive trading days ("20-Day Average Market Price") prior to December 31, 2025. Each PSU may result in the right to receive additional shares of the Issuer's Common Stock, up to a maximum of three shares per PSU, to the extent that the Issuer's Common Stock achieves 20-Day Average Market Prices at specified levels in excess of the target market price prior to December 31, 2025. Vested shares, if any, generally are payable in two equal installments in early 2026 and early 2027.

F4 · price: Awarded under ATI's 2020 Incentive Plan.

F5 · derivative.exercise_date: Each Performance Stock Unit ("PSU") represents a contingent right to receive one share of the Issuer's Common Stock if the Issuer's Common Stock achieves a specified target market price (based on a 20-trading day average) on the NYSE for at least 20 consecutive trading days ("20-Day Average Market Price") prior to December 31, 2025. Each PSU may result in the right to receive additional shares of the Issuer's Common Stock, up to a maximum of three shares per PSU, to the extent that the Issuer's Common Stock achieves 20-Day Average Market Prices at specified levels in excess of the target market price prior to December 31, 2025. Vested shares, if any, generally are payable in two equal installments in early 2026 and early 2027.

F5 · derivative.expiration_date: Each Performance Stock Unit ("PSU") represents a contingent right to receive one share of the Issuer's Common Stock if the Issuer's Common Stock achieves a specified target market price (based on a 20-trading day average) on the NYSE for at least 20 consecutive trading days ("20-Day Average Market Price") prior to December 31, 2025. Each PSU may result in the right to receive additional shares of the Issuer's Common Stock, up to a maximum of three shares per PSU, to the extent that the Issuer's Common Stock achieves 20-Day Average Market Prices at specified levels in excess of the target market price prior to December 31, 2025. Vested shares, if any, generally are payable in two equal installments in early 2026 and early 2027.

SEC source: 0001209191-22-021134 · doc4a.xml · nonDerivative · entry 2

WETHERBEE ROBERT S · CIK 0001572385 · Director · Board Chair, President and CEO

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 384,311.3409

F3 · shares: 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.

F4 · price: Awarded under ATI's 2020 Incentive Plan.

SEC source: 0001209191-22-021134 · doc4a.xml · nonDerivative · entry 1

WETHERBEE ROBERT S · CIK 0001572385 · Director · Board Chair, President and CEO

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 288,703.3409

F1 · shares: Shares withheld for payment of taxes on restricted stock units awarded on January 4, 2021. One-third of such restricted stock units vested by their terms on January 4, 2022.

F2 · price: 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 ("NYSE") on January 4, 2022.

SEC source: 0001209191-22-021128 · doc4a.xml · derivative · entry 3

NEWMAN DONALD P · CIK 0001282236 · EVP and CFO

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 61,538

Underlying: Common Stock · 61,538 shares

Expires 2025-12-31

F5 · derivative.exercise_price: Each Performance Stock Unit ("PSU") represents a contingent right to receive one share of the Issuer's Common Stock if the Issuer's Common Stock achieves a specified target market price (based on a 20-trading day average) on the NYSE for at least 20 consecutive trading days ("20-Day Average Market Price") prior to December 31, 2025. Each PSU may result in the right to receive additional shares of the Issuer's Common Stock, up to a maximum of three shares per PSU, to the extent that the Issuer's Common Stock achieves 20-Day Average Market Prices at specified levels in excess of the target market price prior to December 31, 2025. Vested shares, if any, generally are payable in two equal installments in early 2026 and early 2027.

F4 · price: Awarded under ATI's 2020 Incentive Plan.

F5 · derivative.exercise_date: Each Performance Stock Unit ("PSU") represents a contingent right to receive one share of the Issuer's Common Stock if the Issuer's Common Stock achieves a specified target market price (based on a 20-trading day average) on the NYSE for at least 20 consecutive trading days ("20-Day Average Market Price") prior to December 31, 2025. Each PSU may result in the right to receive additional shares of the Issuer's Common Stock, up to a maximum of three shares per PSU, to the extent that the Issuer's Common Stock achieves 20-Day Average Market Prices at specified levels in excess of the target market price prior to December 31, 2025. Vested shares, if any, generally are payable in two equal installments in early 2026 and early 2027.

F5 · derivative.expiration_date: Each Performance Stock Unit ("PSU") represents a contingent right to receive one share of the Issuer's Common Stock if the Issuer's Common Stock achieves a specified target market price (based on a 20-trading day average) on the NYSE for at least 20 consecutive trading days ("20-Day Average Market Price") prior to December 31, 2025. Each PSU may result in the right to receive additional shares of the Issuer's Common Stock, up to a maximum of three shares per PSU, to the extent that the Issuer's Common Stock achieves 20-Day Average Market Prices at specified levels in excess of the target market price prior to December 31, 2025. Vested shares, if any, generally are payable in two equal installments in early 2026 and early 2027.

SEC source: 0001209191-22-021128 · doc4a.xml · nonDerivative · entry 2

NEWMAN DONALD P · CIK 0001282236 · EVP and CFO

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 150,343

F3 · shares: 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.

F4 · price: Awarded under ATI's 2020 Incentive Plan.

SEC source: 0001209191-22-021128 · doc4a.xml · nonDerivative · entry 1

NEWMAN DONALD P · CIK 0001282236 · EVP and CFO

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 118,793

F1 · shares: Shares withheld for payment of taxes on restricted stock units awarded on January 4, 2021. One-third of such restricted stock units vested by their terms on January 4, 2022.

F2 · price: 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 ("NYSE") on January 4, 2022.

SEC source: 0001209191-22-021122 · doc4a.xml · derivative · entry 3

Fields Kimberly A · CIK 0001773072 · EVP & COO

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 71,795

Underlying: Common Stock · 71,795 shares

Expires 2025-12-31

F5 · derivative.exercise_price: Each Performance Stock Unit ("PSU") represents a contingent right to receive one share of the Issuer's Common Stock if the Issuer's Common Stock achieves a specified target market price (based on a 20-trading day average) on the NYSE for at least 20 consecutive trading days ("20-Day Average Market Price") prior to December 31, 2025. Each PSU may result in the right to receive additional shares of the Issuer's Common Stock, up to a maximum of three shares per PSU, to the extent that the Issuer's Common Stock achieves 20-Day Average Market Prices at specified levels in excess of the target market price prior to December 31, 2025. Vested shares, if any, generally are payable in two equal installments in early 2026 and early 2027.

F4 · price: Awarded under ATI's 2020 Incentive Plan.

F5 · derivative.exercise_date: Each Performance Stock Unit ("PSU") represents a contingent right to receive one share of the Issuer's Common Stock if the Issuer's Common Stock achieves a specified target market price (based on a 20-trading day average) on the NYSE for at least 20 consecutive trading days ("20-Day Average Market Price") prior to December 31, 2025. Each PSU may result in the right to receive additional shares of the Issuer's Common Stock, up to a maximum of three shares per PSU, to the extent that the Issuer's Common Stock achieves 20-Day Average Market Prices at specified levels in excess of the target market price prior to December 31, 2025. Vested shares, if any, generally are payable in two equal installments in early 2026 and early 2027.

F5 · derivative.expiration_date: Each Performance Stock Unit ("PSU") represents a contingent right to receive one share of the Issuer's Common Stock if the Issuer's Common Stock achieves a specified target market price (based on a 20-trading day average) on the NYSE for at least 20 consecutive trading days ("20-Day Average Market Price") prior to December 31, 2025. Each PSU may result in the right to receive additional shares of the Issuer's Common Stock, up to a maximum of three shares per PSU, to the extent that the Issuer's Common Stock achieves 20-Day Average Market Prices at specified levels in excess of the target market price prior to December 31, 2025. Vested shares, if any, generally are payable in two equal installments in early 2026 and early 2027.

SEC source: 0001209191-22-021122 · doc4a.xml · nonDerivative · entry 2

Fields Kimberly A · CIK 0001773072 · EVP & COO

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 131,580

F3 · shares: 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.

F4 · price: Awarded under ATI's 2020 Incentive Plan.

SEC source: 0001209191-22-021122 · doc4a.xml · nonDerivative · entry 1

Fields Kimberly A · CIK 0001773072 · EVP & COO

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 92,142

F1 · shares: Shares withheld for payment of taxes on restricted stock units awarded on January 4, 2021. One-third of such restricted stock units vested by their terms on January 4, 2022.

F2 · price: 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 ("NYSE") on January 4, 2022.

SEC source: 0001209191-21-037554 · doc4.xml · nonDerivative · entry 1

Kramer Kevin B · CIK 0001549592 · Sr. VP, CCMO

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 152,570.3608

F1 · shares: Shares sold pursuant to a 10b5-1 Trading Plan.

F2 · balance_after: 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.

SEC source: 0001209191-21-036138 · doc4.xml · nonDerivative · entry 1

Morehouse David J · CIK 0001635153 · Director

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 54,744.4028

F1 · shares: Annual Director award granted under the Issuer's 2020 Incentive Plan as part of the Issuer's Director compensation program.

F1 · price: Annual Director award granted under the Issuer's 2020 Incentive Plan as part of the Issuer's Director compensation program.

SEC source: 0001209191-21-036135 · doc4.xml · nonDerivative · entry 1

Kah Marianne · CIK 0001779021 · Director

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 22,973

F1 · shares: Annual Director award granted under the Issuer's 2020 Incentive Plan as part of the Issuer's Director compensation program.

F1 · price: Annual Director award granted under the Issuer's 2020 Incentive Plan as part of the Issuer's Director compensation program.

SEC source: 0001209191-21-036130 · doc4.xml · nonDerivative · entry 1

HARVEY J BRETT · CIK 0001241243 · Director

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 78,248.815

F1 · shares: Annual Director award granted under the Issuer's 2020 Incentive Plan as part of the Issuer's Director compensation program.

F1 · price: Annual Director award granted under the Issuer's 2020 Incentive Plan as part of the Issuer's Director compensation program.

SEC source: 0001209191-21-036132 · doc4.xml · nonDerivative · entry 1

Hess David P · CIK 0001304945 · Director

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 20,973

F1 · shares: Annual Director award granted under the Issuer's 2020 Incentive Plan as part of the Issuer's Director compensation program.

F1 · price: Annual Director award granted under the Issuer's 2020 Incentive Plan as part of the Issuer's Director compensation program.

SEC source: 0001209191-21-036129 · doc4.xml · nonDerivative · entry 1

DIGGS JAMES C · CIK 0001200401 · Director

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 54,260.815

F1 · shares: Annual Director award granted under the Issuer's 2020 Incentive Plan as part of the Issuer's Director compensation program.

F1 · price: Annual Director award granted under the Issuer's 2020 Incentive Plan as part of the Issuer's Director compensation program.

SEC source: 0001209191-21-036128 · doc4.xml · nonDerivative · entry 1

Corvi Carolyn · CIK 0001465541 · Director

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 59,027.6932

F1 · shares: Annual Director award granted under the Issuer's 2020 Incentive Plan as part of the Issuer's Director compensation program.

F1 · price: Annual Director award granted under the Issuer's 2020 Incentive Plan as part of the Issuer's Director compensation program.

SEC source: 0001209191-21-036127 · doc4.xml · nonDerivative · entry 1

Carlisle Herbert J · CIK 0001732898 · Director

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 25,438

F1 · shares: Annual Director award granted under the Issuer's 2020 Incentive Plan as part of the Issuer's Director compensation program.

F1 · price: Annual Director award granted under the Issuer's 2020 Incentive Plan as part of the Issuer's Director compensation program.

SEC source: 0001209191-21-036126 · doc4.xml · nonDerivative · entry 1

BALL M LEROY · CIK 0001229771 · Director

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 24,254

F1 · shares: Annual Director award granted under the Issuer's 2020 Incentive Plan as part of the Issuer's Director compensation program.

F1 · price: Annual Director award granted under the Issuer's 2020 Incentive Plan as part of the Issuer's Director compensation program.

SEC source: 0001209191-21-032788 · doc4.xml · nonDerivative · entry 1

Kah Marianne · CIK 0001779021 · Director

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 18,626

F1 · shares: Shares withheld for payment of taxes in connection with the May 12, 2021 vesting of restricted stock granted in May 2020.

F2 · price: 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 May 12, 2021.

F1 · balance_after: Shares withheld for payment of taxes in connection with the May 12, 2021 vesting of restricted stock granted in May 2020.

SEC source: 0001209191-21-032785 · doc4.xml · nonDerivative · entry 1

Hess David P · CIK 0001304945 · Director

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 16,626

F1 · shares: Shares withheld for payment of taxes in connection with the May 12, 2021 vesting of restricted stock granted in May 2020.

F2 · price: 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 May 12, 2021.

F1 · balance_after: Shares withheld for payment of taxes in connection with the May 12, 2021 vesting of restricted stock granted in May 2020.

SEC source: 0001209191-21-032779 · doc4.xml · nonDerivative · entry 1

HARVEY J BRETT · CIK 0001241243 · Director

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 70,739.815

F1 · shares: Shares withheld for payment of taxes in connection with the May 12, 2021 vesting of restricted stock granted in May 2020.

F2 · price: 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 May 12, 2021.

F1 · balance_after: Shares withheld for payment of taxes in connection with the May 12, 2021 vesting of restricted stock granted in May 2020.

SEC source: 0001209191-21-032776 · doc4.xml · nonDerivative · entry 1

DIGGS JAMES C · CIK 0001200401 · Director

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 49,913.8151

F1 · shares: Shares withheld for payment of taxes in connection with the May 12, 2021 vesting of restricted stock granted in May 2020.

F2 · price: 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 May 12, 2021.

F1 · balance_after: Shares withheld for payment of taxes in connection with the May 12, 2021 vesting of restricted stock granted in May 2020.

SEC source: 0001209191-21-032771 · doc4.xml · nonDerivative · entry 1

Corvi Carolyn · CIK 0001465541 · Director

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 54,680.6932

F1 · shares: Shares withheld for payment of taxes in connection with the May 12, 2021 vesting of restricted stock granted in May 2020.

F2 · price: 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 May 12, 2021.

F1 · balance_after: Shares withheld for payment of taxes in connection with the May 12, 2021 vesting of restricted stock granted in May 2020.

SEC source: 0001209191-21-032767 · doc4.xml · nonDerivative · entry 1

Carlisle Herbert J · CIK 0001732898 · Director

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 21,091

F1 · shares: Shares withheld for payment of taxes in connection with the May 12, 2021 vesting of restricted stock granted in May 2020.

F2 · price: 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 May 12, 2021.

F1 · balance_after: Shares withheld for payment of taxes in connection with the May 12, 2021 vesting of restricted stock granted in May 2020.

SEC source: 0001209191-21-021588 · doc4.xml · nonDerivative · entry 2

Kramer Kevin B · CIK 0001549592 · Sr. VP, CCMO

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 162,570.3608

F1 · shares: Shares sold pursuant to a 10b5-1 Trading Plan.

F2 · balance_after: 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.

SEC source: 0001209191-21-021588 · doc4.xml · nonDerivative · entry 1

Kramer Kevin B · CIK 0001549592 · Sr. VP, CCMO

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 162,670.3608

F1 · shares: Shares sold pursuant to a 10b5-1 Trading Plan.

F2 · balance_after: 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.

SEC source: 0001209191-21-020162 · doc4.xml · nonDerivative · entry 1

Davis Elliot S · CIK 0001520037 · Sr VP, GC, CCO and Secretary

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 191,571.4709

F1 · shares: Shares sold pursuant to a 10b5-1 Trading Plan.

SEC source: 0001209191-21-018645 · doc4.xml · nonDerivative · entry 1

Davis Elliot S · CIK 0001520037 · Sr VP, GC, CCO and Secretary

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 206,771.4709

F1 · shares: Shares sold pursuant to a 10b5-1 Trading Plan.

SEC source: 0001209191-21-017434 · doc4.xml · nonDerivative · entry 1

Schwartz Karl D · CIK 0001498160 · VP, Controller & CAO

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 62,260.9743

F1 · shares: Shares withheld for payment of taxes on restricted stock units awarded on February 27, 2019. One-third of such restricted stock units vested by their terms on March 1, 2021.

F2 · price: 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 March 1, 2021.

F3 · balance_after: This amount includes 6,184.724781 shares of common stock Mr. Schwartz owns in the Company's 401(k) plan. Fluctuations in 401(k) share amounts reflect the plan's unit reporting method. The reporting person holds approximately 5,191 units, which represent interests in the Company's stock fund.

SEC source: 0001209191-21-017422 · doc4.xml · nonDerivative · entry 1

WETHERBEE ROBERT S · CIK 0001572385 · President and CEO

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 306,479.3409

F1 · shares: Shares withheld for payment of taxes on restricted stock units awarded on February 27, 2019. One-third of such restricted stock units vested by their terms on March 1, 2021.

F2 · price: 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 March 1, 2021.

SEC source: 0001209191-21-017418 · doc4.xml · nonDerivative · entry 1

Powers Elizabeth C · CIK 0001332656 · Senior VP, CHRO

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 150,506.8867

F1 · shares: Shares withheld for payment of taxes on restricted stock units awarded on February 27, 2019. One-third of such restricted stock units vested by their terms on March 1, 2021.

F2 · price: 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 March 1, 2021.

F3 · balance_after: This amount includes 1,693.349759 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 1,422 units, which represent interests in the Company's stock fund.

SEC source: 0001209191-21-017415 · doc4.xml · nonDerivative · entry 1

Kramer Kevin B · CIK 0001549592 · Sr. VP, CCMO

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 172,570.3608

F1 · shares: Shares withheld for payment of taxes on restricted stock units awarded on February 27, 2019. One-third of such restricted stock units vested by their terms on March 1, 2021.

F2 · price: 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 March 1, 2021.

F3 · balance_after: This amount includes 1,288.282579 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 1,082 units, which represent interests in the Company's stock fund. This amount includes 1,288.282579 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 1,082 units, which represent interests in the Company's stock fund.

SEC source: 0001209191-21-017402 · doc4.xml · nonDerivative · entry 1

Fields Kimberly A · CIK 0001773072 · EVP

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 99,299

F1 · shares: Shares withheld for payment of taxes on restricted stock units that vested by their terms on March 1, 2021.

F2 · price: 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 March 1, 2021.

SEC source: 0001209191-21-017408 · doc4.xml · nonDerivative · entry 1

Harris Timothy J · CIK 0001776844 · Senior VP and CDIO

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 70,235

F1 · shares: Shares withheld for payment of taxes on restricted stock units that vested by their terms on March 1, 2021.

F2 · price: 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 March 1, 2021.

SEC source: 0001209191-21-017394 · doc4.xml · nonDerivative · entry 1

Davis Elliot S · CIK 0001520037 · Sr VP, GC, CCO and Secretary

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 215,004.4709

F1 · shares: Shares withheld for payment of taxes on restricted stock units awarded on February 27, 2019. One-third of such restricted stock units vested by their terms on March 1, 2021.

F2 · price: 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 March 1, 2021.