KIRBY CORP

The Company continues to be subject to the risk factors previously disclosed in its “Risk Factors” in Part I, Item 1A of the Company’s Annual Report on Form 10-K for the year ended December 31, 2025 and in Part II, Item 1A, “Risk Factors,” of its Quarterly Report on Form 10-Q for the quarter ended March 31, 2026. Since the filing of its Form 10‑K, the U.S. government issued a 60‑day waiver of the Jones Act on March 17, 2026, and subsequently extended the waiver for an additional 90 days beginning May 18, 2026, and ending August 16, 2026. The waiver may increase competition from non‑U.S. vessels in certain markets served by the Company. Although the Company has not experienced a material adverse impact from the waiver to date, any further extension, expansion, or future reinstatement of the waiver could adversely affect the Company’s operations, financial condition, and results of operations, and there can be no assurance that such impacts would not be material.

Issuer Purchases of Equity Securities

Purchases of the Company’s common stock during the 2026 second quarter were made in the open market pursuant to a discretionary authorization by the Board of Directors. For more information about stock purchases in the 2026 first six months and other information responsive to this Item, see “Treasury Stock Purchases” in Financial Condition, Capital Resources and Liquidity included in Part I, Item 2. Management’s Discussion and Analysis of Financial Condition and Results of Operations.