11. Stock-Based Compensation

2025 Stock Incentive Plan

Cardinal Infrastructure Group Inc. adopted the 2025 Stock Incentive Plan (the “2025 Plan”) on November 13, 2025, with stockholder approval on the same date. The 2025 Plan is designed to attract, retain, and motivate employees, officers, directors, and consultants by providing for equity‑based compensation aligned with long‑term stockholder value. It authorizes up to 3,660,656 shares of Class A common stock for issuance, with the share reserve eligible for an automatic annual increase of up to 5% of outstanding shares beginning with the first fiscal year after the Company’s registration date, unless the Compensation Committee elects otherwise. Shares underlying awards that are forfeited, canceled, expired, or settled in cash are returned to the plan.

The 2025 Plan may be used to grant stock options (both incentive and nonqualified), restricted stock, restricted stock units, stock appreciation rights, and other stock‑based awards. It is administered by the Board of Directors or a designated committee, which has broad authority to determine award terms, vesting conditions, performance goals, and to interpret the plan, including the ability to accelerate vesting in certain circumstances. The 2025 Plan includes a detailed definition of a Change in Control, covering specified acquisitions of voting power, board turnover, mergers, consolidations, and significant asset transactions. The plan will remain in effect until November 13, 2035, unless earlier terminated or extended.

In connection with the acquisition of ALGC (refer to Note 3), the Company issued 345,666 shares of Class A Common Stock, par value $0.0001 per share, from its 2025 Stock Incentive Plan to employees of, and service providers to, ALGC at the direction of the selling shareholders. The shares were fully vested at issuance and were not subject to any service or other vesting conditions. Because the shares were issued at the direction of the selling shareholders to settle existing arrangements with the recipients, they were treated as consideration transferred in the business combination rather than post-combination compensation expense. The shares were valued at $8,489,557, based on the Company's closing share price of $24.56 on the acquisition date.

As of March 31, 2026, in addition to the ALGC Class A awards, the December 2025 Director Stock Awards, and the 2026 Director Retainer awards discussed below were issued under the Plan. As of March 31, 2026 there were 3,276,757 shares of Class A common stock available for issuance under the plan.

December 2025 Director Stock Awards & 2026 Retainer Awards

In November 2025, the Board of Directors approved a Non-Employee Director Compensation Program under which directors receive annual cash retainers and equity grants pursuant to the 2025 Stock Incentive Plan. Each non-employee director is entitled to an annual cash retainer of $75,000 and an annual grant of restricted stock units (RSUs) with a grant date fair value of $100,000, generally awarded at the Company’s annual meeting and vesting on the earlier of the next annual meeting or the first anniversary of the grant date. Committee chairpersons receive an additional annual RSU grant valued at $12,500, and other committee members receive RSUs valued at $5,000 annually. Directors may elect to receive their cash retainer in the form of RSUs, which vest quarterly. In connection with the Company’s IPO, newly appointed directors received RSU grants with a fair value of $18,750 (in lieu of a prorated cash retainer for 2025), vesting on December 31, 2025, as well as RSUs valued at $100,000 plus applicable committee grants, each vesting on the first anniversary of the grant date.

Prior to the Non-Employee Director Compensation Program the directors elected to receive their 2025 cash retainer in the form of RSUs. As a result of this election, the Company recognized an additional grant of 12,404 RSU’s in the three months ended March 2025 and recognized $191,852 of stock-based compensation expense. The fair value of the restricted stock units was based on the Company’s closing share price on December 31, 2025 of $24.18 per share, which represents a Level 1 input under the fair value hierarchy.

As of March 31, 2026, the Company had $547,380 of unrecognized compensation cost related to 31,565 unvested awards, based on a weighted‑average grant‑date fair value of $21.93 per award. This amount is expected to be recognized over a weighted‑average period of 12 months, corresponding to the remaining service period through December 31, 2026.