Company Update

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15 (d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): September 27, 2018 INTERNATIONAL BANCSHARES CORPORATION (Exact Name of Registrant as Specified in its Charter) Texas 000-09439 74-2157138 (State or other Jurisdiction (Commission File Number) (I.R.S. Employer of incorporation or organization) Identification No.) 1200 San Bernardo, Laredo, Texas 78040-1359 (Address of principal executive offices) (ZIP Code) (Registrant’s telephone number, including area code) (956) 722-7611 None (Former name or former address, if changed since last report) Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General Instruction A.2. below); o             Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425) o             Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12) o             Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b)) o             Pre-commencement communications pursuant to Rule 13e-4 (c) under the Exchange Act (17 CFR 240.13e-4 (c)) Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter). Emerging growth company o If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. o Item 8.01                                            Other Events On September 27, 2018, International Bancshares Corporation (“IBC”) issued a news release announcing today, its Board of Directors approved the declaration of a forty-two cents per share cash dividend for shareholders of record of Common Stock, $1.00 par value, as of the close of business on October 9, 2018, payable on October 16, 2018. The news release announcing the cash dividend, attached hereto and filed herewith as Exhibit 99, is incorporated herein by reference. All of the information furnished in Item 8.01 of this report and the accompanying exhibits is also intended to be included under “Item 7.01 — Regulation Fair Disclosure,” shall not be deemed to be “filed” for the purposes of Section 18 of the Securities and Exchange Act of 1934, as amended, is not subject to the liabilities of that section and shall not be incorporated by reference in any filing under the Securities Act of 1933, as amended. Item 9.01                                            Financial Statements and Exhibits. 99                                   News Release of International Bancshares Corporation dated September 27, 2018 EXHIBIT INDEX Exhibit Number Description 99 News Release of International Bancshares Corporation dated September 27, 2018 2 SIGNATURES Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized. INTERNATIONAL BANCSHARES CORPORATION (Registrant) By: /s/ Dennis E. Nixon Dennis E. Nixon, President and CEO September 27, 2018 3