Christopher P. Sighinolfi - 18 Feb 2025 Form 4 Insider Report for ONE Gas, Inc. (OGS)

Footnote F1

Performance units awarded under the Issuer's Amended and Restated Equity Compensation Plan (2018) (the "ECP"). The award, including dividend equivalents, vested on February 15, 2025, in an amount equal to 50% of the performance units awarded based upon Issuer's total shareholder return compared to the total shareholder return of a selected peer group and was certified by the Executive Compensation Committee of the Board of Directors on February 17, 2025. The reporting person's receipt of 758.352 shares of common stock was deferred under the ECP resulting in the reporting person's receipt of 758.352 deferred stock units. The deferred stock units become payable in shares of common stock after the reporting person's termination of service, pursuant to the reporting person's distribution election under the ECP. The reporting person is therefore reporting the disposition of 758.352 shares of common stock in exchange for an equal number of deferred stock units.

Footnote F2

(Continued from footnote 1) The reporting person had 59.149 shares withheld and cancelled in respect of taxes in connection with the vesting of the performance units.

Footnote F3

Restricted units awarded under Issuer's Amended and Restated Equity Compensation Plan (2018). The award vested on February 15, 2025. During the 3-year vesting period, the award was credited with dividend equivalents that were paid out in shares of common stock at the time the underlying units vested and were issued. The award and credited dividend equivalents were payable one share of the Issuer's common stock for each vested restricted unit, including additional restricted units resulting from the dividend equivalents.

Footnote F4

Performance units awarded under the Issuer's Amended and Restated Equity Compensation Plan (2018). The award will vest on February 19, 2028, for a percentage (0% to 200%) of the performance units awarded based upon the Issuer's total shareholder return compared to total stockholder return of a selected peer group over the performance period from January 1, 2025, through December 31, 2027, in accordance with the terms of the Performance Unit Award Agreement. During the 3-year vesting period, the award will be credited with dividend equivalents that will be paid out at the time the underlying units are issued. The award and credited dividend equivalents will be payable one share of the Issuer's common stock for each vested performance unit and dividend equivalent.

Footnote F5

Restricted units awarded under the Issuer's Amended and Restated Equity Compensation Plan (2018). The award vests on February 19, 2028, in accordance with the terms of the Restricted Unit Award Agreement. During the 3-year vesting period, the award will be credited with dividend equivalents that will be paid out at the time the underlying units are issued. The award and credited dividend equivalents will be payable one share of the Issuer's common stock for each vested restricted unit and dividend equivalent.