Insider transactions

Exercise or conversion of derivative security exempted pursuant to Rule 16b-3

Open market or private sale of non-derivative or derivative security

• F1 Represents the weighted average sale price. The highest price at which shares were sold was $188.2437 and the lowest price at which shares were sold was $187.2450. Information regarding the number of shares sold at each separate price will be made available from the reporting person upon request by the SEC, the issuer or its shareholders.

Open market or private sale of non-derivative or derivative security

• F2 Represents the weighted average sale price. The highest price at which shares were sold was $188.3895 and the lowest price at which shares were sold was $188.2600. Information regarding the number of shares sold at each separate price will be made available from the reporting person upon request by the SEC, the issuer or its shareholders.

Exercise or conversion of derivative security exempted pursuant to Rule 16b-3

Open market or private sale of non-derivative or derivative security

Exercise or conversion of derivative security exempted pursuant to Rule 16b-3

Open market or private sale of non-derivative or derivative security

• F1 Represents the weighted average sale price. The highest price at which shares were sold was $187.3300 and the lowest price at which shares were sold was $186.6100. Information regarding the number of shares sold at each separate price will be made available from the reporting person upon request by the SEC, the issuer or its shareholders.

Open market or private sale of non-derivative or derivative security

• F2 Represents the weighted average sale price. The highest price at which shares were sold was $187.8229 and the lowest price at which shares were sold was $187.7050. Information regarding the number of shares sold at each separate price will be made available from the reporting person upon request by the SEC, the issuer or its shareholders.

Exercise or conversion of derivative security exempted pursuant to Rule 16b-3

Exercise or conversion of derivative security exempted pursuant to Rule 16b-3

Open market or private sale of non-derivative or derivative security

• F1 Represents the weighted average sale price. The highest price at which shares were sold was $185.8300 and the lowest price at which shares were sold was $184.9200. Information regarding the number of shares sold at each separate price will be made available from the reporting person upon request by the SEC, the issuer or its shareholders.

Open market or private sale of non-derivative or derivative security

• F2 Represents the weighted average sale price. The highest price at which shares were sold was $186.9450 and the lowest price at which shares were sold was $185.9550. Information regarding the number of shares sold at each separate price will be made available from the reporting person upon request by the SEC, the issuer or its shareholders.

Exercise or conversion of derivative security exempted pursuant to Rule 16b-3

Grant, award or other acquisition pursuant to Rule 16b-3(d)

• F1 Represents additional shares of phantom stock/RSUs credited to the reporting person's account under the Amended and Restated GATX Directors' Phantom Stock Plan (Phantom Stock Plan) and the Amended and Restated GATX Corporation Directors' Voluntary Deferred Fee Plan (Deferred Fee Plan) on the transaction date. Each share of phantom stock/RSU represents the right to receive one share of Issuer's common stock upon settlement. The shares of phantom stock/RSUs are generally payable on a deferred basis in common stock at the election of the reporting person upon the reporting person's termination of service on the Issuer's board of directors.
• F2 Represents 169 shares of phantom stock/RSUs acquired pursuant to the dividend reinvestment feature of the Phantom Stock Plan and the Deferred Fee Plan.

Grant, award or other acquisition pursuant to Rule 16b-3(d)

• F1 Represents additional shares of phantom stock/RSUs credited to the reporting person's account under the Amended and Restated GATX Directors' Phantom Stock Plan (Phantom Stock Plan) and the Amended and Restated GATX Corporation Directors' Voluntary Deferred Fee Plan (Deferred Fee Plan) on the transaction date. Each share of phantom stock/RSU represents the right to receive one share of Issuer's common stock upon settlement. The shares of phantom stock/RSUs are generally payable on a deferred basis in common stock at the election of the reporting person upon the reporting person's termination of service on the Issuer's board of directors.
• F2 Represents (a) 4 shares of phantom stock/RSUs acquired pursuant to the dividend reinvestment feature of the Phantom Stock Plan and Deferred Fee Plan, and (b) 124 RSUs acquired under the Deferred Fee Plan resulting from the reporting person's election to defer the annual cash retainer and other cash fees payable to the reporting person in the form of RSUs under the Deferred Fee Plan.

Grant, award or other acquisition pursuant to Rule 16b-3(d)

• F1 Represents additional shares of phantom stock/RSUs credited to the reporting person's account under the Amended and Restated GATX Directors' Phantom Stock Plan (Phantom Stock Plan) and the Amended and Restated GATX Corporation Directors' Voluntary Deferred Fee Plan (Deferred Fee Plan) on the transaction date. Each share of phantom stock/RSU represents the right to receive one share of Issuer's common stock upon settlement. The shares of phantom stock/RSUs are generally payable on a deferred basis in common stock at the election of the reporting person upon the reporting person's termination of service on the Issuer's board of directors.
• F2 Represents 29 shares of phantom stock/RSUs acquired pursuant to the dividend reinvestment feature of the Phantom Stock Plan and the Deferred Fee Plan.

Grant, award or other acquisition pursuant to Rule 16b-3(d)

• F1 Represents additional shares of phantom stock/RSUs credited to the reporting person's account under the Amended and Restated GATX Directors' Phantom Stock Plan (Phantom Stock Plan) and the Amended and Restated GATX Corporation Directors' Voluntary Deferred Fee Plan (Deferred Fee Plan) on the transaction date. Each share of phantom stock/RSU represents the right to receive one share of Issuer's common stock upon settlement. The shares of phantom stock/RSUs are generally payable on a deferred basis in common stock at the election of the reporting person upon the reporting person's termination of service on the Issuer's board of directors.
• F2 Represents (a) 16 shares of phantom stock/RSUs acquired pursuant to the dividend reinvestment feature of the Phantom Stock Plan and Deferred Fee Plan, and (b) 124 RSUs acquired under the Deferred Fee Plan resulting from the reporting person's election to defer the annual cash retainer and other cash fees payable to the reporting person in the form of RSUs under the Deferred Fee Plan.

Grant, award or other acquisition pursuant to Rule 16b-3(d)

• F1 Represents additional shares of phantom stock/RSUs credited to the reporting person's account under the Amended and Restated GATX Directors' Phantom Stock Plan (Phantom Stock Plan) and the Amended and Restated GATX Corporation Directors' Voluntary Deferred Fee Plan (Deferred Fee Plan) on the transaction date. Each share of phantom stock/RSU represents the right to receive one share of Issuer's common stock upon settlement. The shares of phantom stock/RSUs are generally payable on a deferred basis in common stock at the election of the reporting person upon the reporting person's termination of service on the Issuer's board of directors.
• F2 Represents 72 shares of phantom stock/RSUs acquired pursuant to the dividend reinvestment feature of the Phantom Stock Plan and the Deferred Fee Plan.

Grant, award or other acquisition pursuant to Rule 16b-3(d)

• F1 Represents additional shares of phantom stock/RSUs credited to the reporting person's account under the Amended and Restated GATX Directors' Phantom Stock Plan (Phantom Stock Plan) and the Amended and Restated GATX Corporation Directors' Voluntary Deferred Fee Plan (Deferred Fee Plan) on the transaction date. Each share of phantom stock/RSU represents the right to receive one share of Issuer's common stock upon settlement. The shares of phantom stock/RSUs are generally payable on a deferred basis in common stock at the election of the reporting person upon the reporting person's termination of service on the Issuer's board of directors.
• F2 Represents (a) 17 shares of phantom stock/RSUs acquired pursuant to the dividend reinvestment feature of the Phantom Stock Plan and Deferred Fee Plan, and (b) 124 RSUs acquired under the Deferred Fee Plan resulting from the reporting person's election to defer the annual cash retainer and other cash fees payable to the reporting person in the form of RSUs under the Deferred Fee Plan.

Grant, award or other acquisition pursuant to Rule 16b-3(d)

• F1 Represents additional shares of phantom stock/RSUs credited to the reporting person's account under the Amended and Restated GATX Directors' Phantom Stock Plan (Phantom Stock Plan) and the Amended and Restated GATX Corporation Directors' Voluntary Deferred Fee Plan (Deferred Fee Plan) on the transaction date. Each share of phantom stock/RSU represents the right to receive one share of Issuer's common stock upon settlement. The shares of phantom stock/RSUs are generally payable on a deferred basis in common stock at the election of the reporting person upon the reporting person's termination of service on the Issuer's board of directors.
• F2 Represents 134 shares of phantom stock/RSUs acquired pursuant to the dividend reinvestment feature of the Phantom Stock Plan and the Deferred Fee Plan.

Grant, award or other acquisition pursuant to Rule 16b-3(d)

• F1 Represents additional shares of phantom stock/RSUs credited to the reporting person's account under the Amended and Restated GATX Directors' Phantom Stock Plan (Phantom Stock Plan) and the Amended and Restated GATX Corporation Directors' Voluntary Deferred Fee Plan (Deferred Fee Plan) on the transaction date. Each share of phantom stock/RSU represents the right to receive one share of Issuer's common stock upon settlement. The shares of phantom stock/RSUs are generally payable on a deferred basis in common stock at the election of the reporting person upon the reporting person's termination of service on the Issuer's board of directors.
• F2 Represents 122 shares of phantom stock/RSUs acquired pursuant to the dividend reinvestment feature of the Phantom Stock Plan and the Deferred Fee Plan.

Exercise or conversion of derivative security exempted pursuant to Rule 16b-3

Open market or private sale of non-derivative or derivative security

• F1 Represents the weighted average sale price. The highest price at which shares were sold was $177.1900 and the lowest price at which shares were sold was $176.9450. Information regarding the number of shares sold at each separate price will be made available from the reporting person upon request by the SEC, the issuer or its shareholders.

Open market or private sale of non-derivative or derivative security

Open market or private sale of non-derivative or derivative security

• F2 Represents the weighted average sale price. The highest price at which shares were sold was $179.5400 and the lowest price at which shares were sold was $179.4900. Information regarding the number of shares sold at each separate price will be made available from the reporting person upon request by the SEC, the issuer or its shareholders.

Exercise or conversion of derivative security exempted pursuant to Rule 16b-3

Bona fide gift

• F1 On September 3, 2026, the reporting person transferred 6,472 shares of GATX common stock to the Geoffrey D Phillips Living Trust U/A DTD 06/18/2021 for no consideration. The reporting person is the trustee of the trust, and members of his immediate family are the sole beneficiaries of the trust. The reporting person remains the beneficial owner of the securities held by the trust.

Exercise or conversion of derivative security exempted pursuant to Rule 16b-3

Open market or private sale of non-derivative or derivative security

• F1 Represents the weighted average sale price. The highest price at which shares were sold was $179.8000 and the lowest price at which shares were sold was $179.2900. Information regarding the number of shares sold at each separate price will be made available from the reporting person upon request by the SEC, the issuer or its shareholders.

Exercise or conversion of derivative security exempted pursuant to Rule 16b-3

Payment of exercise price or tax liability by delivering or withholding securities incident to the receipt, exercise or vesting of a security issued in accordance with Rule 16b-3

• F1 Includes 49 shares acquired through the reinvestment of dividends.

Payment of exercise price or tax liability by delivering or withholding securities incident to the receipt, exercise or vesting of a security issued in accordance with Rule 16b-3

Payment of exercise price or tax liability by delivering or withholding securities incident to the receipt, exercise or vesting of a security issued in accordance with Rule 16b-3

• F1 Includes 49 shares acquired through the reinvestment of dividends.

Exercise or conversion of derivative security exempted pursuant to Rule 16b-3

• F1 Includes 2 shares acquired through the reinvestment of dividends.

Open market or private sale of non-derivative or derivative security

• F2 Represents the weighted average sale price. The highest price at which shares were sold was $180.6800 and the lowest price at which shares were sold was $180.0700. Information regarding the number of shares sold at each separate price will be made available from the reporting person upon request by the SEC, the issuer or its shareholders.

Exercise or conversion of derivative security exempted pursuant to Rule 16b-3

Exercise or conversion of derivative security exempted pursuant to Rule 16b-3

• F1 Includes 42 shares acquired through the reinvestment of dividends.

Open market or private sale of non-derivative or derivative security

• F2 Represents the weighted average sale price. The highest price at which shares were sold was $180.1500 and the lowest price at which shares were sold was $179.1800. Information regarding the number of shares sold at each separate price will be made available from the reporting person upon request by the SEC, the issuer or its shareholders.

Open market or private sale of non-derivative or derivative security

• F3 Represents the weighted average sale price. The highest price at which shares were sold was $181.1850 and the lowest price at which shares were sold was $180.2000. Information regarding the number of shares sold at each separate price will be made available from the reporting person upon request by the SEC, the issuer or its shareholders.

Open market or private sale of non-derivative or derivative security

• F4 Represents the weighted average sale price. The highest price at which shares were sold was $181.2050 and the lowest price at which shares were sold was $181.2000. Information regarding the number of shares sold at each separate price will be made available from the reporting person upon request by the SEC, the issuer or its shareholders.

Exercise or conversion of derivative security exempted pursuant to Rule 16b-3

Grant, award or other acquisition pursuant to Rule 16b-3(d)

• F1 Represents additional shares of phantom stock/RSUs credited to the reporting person's account under the Amended and Restated GATX Directors' Phantom Stock Plan (Phantom Stock Plan) and the Amended and Restated GATX Corporation Directors' Voluntary Deferred Fee Plan (Deferred Fee Plan) on the transaction date. Each share of phantom stock/RSU represents the right to receive one share of Issuer's common stock upon settlement. The shares of phantom stock/RSUs are generally payable on a deferred basis in common stock at the election of the reporting person upon the reporting person's termination of service on the Issuer's board of directors.
• F2 Represents (a) 3 shares of phantom stock/RSUs acquired pursuant to the dividend reinvestment feature of the Phantom Stock Plan and Deferred Fee Plan, and (b) 126 RSUs acquired under the Deferred Fee Plan resulting from the reporting person's election to defer the annual cash retainer and other cash fees payable to the reporting person in the form of RSUs under the Deferred Fee Plan.

Grant, award or other acquisition pursuant to Rule 16b-3(d)

• F1 Represents additional shares of phantom stock/RSUs credited to the reporting person's account under the Amended and Restated GATX Directors' Phantom Stock Plan (Phantom Stock Plan) and the Amended and Restated GATX Corporation Directors' Voluntary Deferred Fee Plan (Deferred Fee Plan) on the transaction date. Each share of phantom stock/RSU represents the right to receive one share of Issuer's common stock upon settlement. The shares of phantom stock/RSUs are generally payable on a deferred basis in common stock at the election of the reporting person upon the reporting person's termination of service on the Issuer's board of directors.
• F2 Represents 164 shares of phantom stock/RSUs acquired pursuant to the dividend reinvestment feature of the Phantom Stock Plan and the Deferred Fee Plan.

Grant, award or other acquisition pursuant to Rule 16b-3(d)

• F1 Represents additional shares of phantom stock/RSUs credited to the reporting person's account under the Amended and Restated GATX Directors' Phantom Stock Plan (Phantom Stock Plan) and the Amended and Restated GATX Corporation Directors' Voluntary Deferred Fee Plan (Deferred Fee Plan) on the transaction date. Each share of phantom stock/RSU represents the right to receive one share of Issuer's common stock upon settlement. The shares of phantom stock/RSUs are generally payable on a deferred basis in common stock at the election of the reporting person upon the reporting person's termination of service on the Issuer's board of directors.
• F2 Represents (a) 15 shares of phantom stock/RSUs acquired pursuant to the dividend reinvestment feature of the Phantom Stock Plan and Deferred Fee Plan, and (b) 126 RSUs acquired under the Deferred Fee Plan resulting from the reporting person's election to defer the annual cash retainer and other cash fees payable to the reporting person in the form of RSUs under the Deferred Fee Plan.

Grant, award or other acquisition pursuant to Rule 16b-3(d)

• F1 Represents additional shares of phantom stock/RSUs credited to the reporting person's account under the Amended and Restated GATX Directors' Phantom Stock Plan (Phantom Stock Plan) and the Amended and Restated GATX Corporation Directors' Voluntary Deferred Fee Plan (Deferred Fee Plan) on the transaction date. Each share of phantom stock/RSU represents the right to receive one share of Issuer's common stock upon settlement. The shares of phantom stock/RSUs are generally payable on a deferred basis in common stock at the election of the reporting person upon the reporting person's termination of service on the Issuer's board of directors.
• F2 Represents 70 shares of phantom stock/RSUs acquired pursuant to the dividend reinvestment feature of the Phantom Stock Plan and the Deferred Fee Plan.

Grant, award or other acquisition pursuant to Rule 16b-3(d)

• F1 Represents additional shares of phantom stock/RSUs credited to the reporting person's account under the Amended and Restated GATX Directors' Phantom Stock Plan (Phantom Stock Plan) and the Amended and Restated GATX Corporation Directors' Voluntary Deferred Fee Plan (Deferred Fee Plan) on the transaction date. Each share of phantom stock/RSU represents the right to receive one share of Issuer's common stock upon settlement. The shares of phantom stock/RSUs are generally payable on a deferred basis in common stock at the election of the reporting person upon the reporting person's termination of service on the Issuer's board of directors.
• F2 Represents (a) 16 shares of phantom stock/RSUs acquired pursuant to the dividend reinvestment feature of the Phantom Stock Plan and Deferred Fee Plan, and (b) 126 RSUs acquired under the Deferred Fee Plan resulting from the reporting person's election to defer the annual cash retainer and other cash fees payable to the reporting person in the form of RSUs under the Deferred Fee Plan.

Grant, award or other acquisition pursuant to Rule 16b-3(d)

• F1 Represents additional shares of phantom stock/RSUs credited to the reporting person's account under the Amended and Restated GATX Directors' Phantom Stock Plan (Phantom Stock Plan) and the Amended and Restated GATX Corporation Directors' Voluntary Deferred Fee Plan (Deferred Fee Plan) on the transaction date. Each share of phantom stock/RSU represents the right to receive one share of Issuer's common stock upon settlement. The shares of phantom stock/RSUs are generally payable on a deferred basis in common stock at the election of the reporting person upon the reporting person's termination of service on the Issuer's board of directors.
• F2 Represents 118 shares of phantom stock/RSUs acquired pursuant to the dividend reinvestment feature of the Phantom Stock Plan and the Deferred Fee Plan.

Grant, award or other acquisition pursuant to Rule 16b-3(d)

• F1 Represents additional shares of phantom stock/RSUs credited to the reporting person's account under the Amended and Restated GATX Directors' Phantom Stock Plan (Phantom Stock Plan) and the Amended and Restated GATX Corporation Directors' Voluntary Deferred Fee Plan (Deferred Fee Plan) on the transaction date. Each share of phantom stock/RSU represents the right to receive one share of Issuer's common stock upon settlement. The shares of phantom stock/RSUs are generally payable on a deferred basis in common stock at the election of the reporting person upon the reporting person's termination of service on the Issuer's board of directors.
• F2 Represents 28 shares of phantom stock/RSUs acquired pursuant to the dividend reinvestment feature of the Phantom Stock Plan and the Deferred Fee Plan.

Grant, award or other acquisition pursuant to Rule 16b-3(d)

• F1 Represents additional shares of phantom stock/RSUs credited to the reporting person's account under the Amended and Restated GATX Directors' Phantom Stock Plan (Phantom Stock Plan) and the Amended and Restated GATX Corporation Directors' Voluntary Deferred Fee Plan (Deferred Fee Plan) on the transaction date. Each share of phantom stock/RSU represents the right to receive one share of Issuer's common stock upon settlement. The shares of phantom stock/RSUs are generally payable on a deferred basis in common stock at the election of the reporting person upon the reporting person's termination of service on the Issuer's board of directors.
• F2 Represents 130 shares of phantom stock/RSUs acquired pursuant to the dividend reinvestment feature of the Phantom Stock Plan and the Deferred Fee Plan.

Exercise or conversion of derivative security exempted pursuant to Rule 16b-3