International Bancshares SEC Filings

Dimensional Fund Advisors LP reports beneficial ownership of 3,206,231 shares of International Bancshares Corp common stock, representing 5.2% of the class. Dimensional disclaims beneficial ownership and states the shares are owned by multiple funds for which it acts as investment adviser, manager or sub‑adviser; the filing shows sole voting power over 3,121,918 shares and sole dispositive power over 3,206,231 shares. The disclosure clarifies these holdings are on behalf of pooled vehicles and not held to influence control of the issuer.

Judith I. Wawroski, Treasurer and Director of International Bancshares Corporation (IBOC), reported transactions on 09/05/2025 involving stock appreciation rights (SARs). The filing shows 600 SARs were treated as vested and payable, resulting in a reported simultaneous purchase and sale of 600 shares at a closing price of $71.58 on the exercise date and a deemed acquisition price of $39.33 per share for valuation purposes. The reporting person did not receive any actual shares because the SARs were cash-settled. Following the transactions, the filing lists 11,172 shares beneficially owned and 3,400 SAR-related derivative units remaining.

Antonio R. Sanchez Jr., a director and 10% owner of International Bancshares Corp (IBOC), reported dispositions of company common stock in two transactions. The Form 4 shows sales of 80,000 shares on 08/14/2025 at a weighted average price of $69.83 and 40,000 shares on 08/15/2025 at a weighted average price of $68.12, for a total of 120,000 shares sold. The filing lists multiple holdings across direct and indirect vehicles, including a direct position of 1,805,554 shares and several indirect positions held in trust and partnership; the record shows beneficial ownership figures of 487,439 and 447,439 shares associated with partnership holdings following the reported sales. The reporting person certified the transactions and provided price-range explanations for the weighted averages.

International Bancshares Corp (IBOC) Form 144 notice shows a proposed sale of 120,000 shares of common stock through Piper Sandler & Co., with an aggregate market value of $8,503,200.00. The sale is scheduled for 08/14/2025 on NASDAQ. The shares were acquired on 07/23/1996 as a partnership contribution from Santig Ltd, and payment was recorded on the acquisition date. The filer reports no securities sold in the past three months for the person on whose account these shares will be sold. The notice includes the required representation that the seller is not aware of undisclosed material adverse information about the issuer.

International Bancshares Corporation adopted Second Amended and Restated By-Laws effective August 6, 2025. The By-Laws require that a shareholder or group beneficially own 3% of IBC's common stock to institute or maintain a derivative proceeding. They designate the Texas Business Court, Fourth Business Court Division, or if that court lacks jurisdiction the U.S. District Court for the Southern District of Texas, or if that court lacks jurisdiction the state district court of Webb County as the sole and exclusive forum for filings unless agreed otherwise. The By-Laws also provide that, to the fullest extent permitted by law, shareholders, directors, and officers irrevocably and unconditionally waive any right to a trial by jury in internal entity claims and other claims against IBC, and state that purchasers or holders of IBC stock are deemed to have notice of and consented to these provisions. A copy of the By-Laws is attached as Exhibit 3.1.

International Bancshares Corp. (NASDAQ: IBOC) filed a Form 8-K on August 1, 2025 to disclose a shareholder-return action under Item 8.01. The Board of Directors approved a semi-annual $0.70 per-share cash dividend on the company’s common stock.

Key dates: shareholders of record as of August 15, 2025 will receive payment on August 29, 2025. The related press release is furnished as Exhibit 99 and incorporated by reference. No other operational metrics, guidance, or transactions were reported; the disclosure is furnished for Regulation FD purposes and is not deemed “filed” under Section 18 of the Exchange Act.