Shareholders at Third Coast (NYSE: TCBX) approve stock issuance for Keystone merger

Rhea-AI Filing Summary

Third Coast Bancshares, Inc. reported that its shareholders approved the issuance of additional common shares needed to complete its planned merger with Keystone Bancshares, Inc. Under the merger agreement, Arch Merger Sub, Inc. will merge into Keystone, which will survive as a wholly owned subsidiary of Third Coast.

At the special meeting held on January 23, 2026, shareholders voted on a proposal to approve the Third Coast share issuance, including for purposes of complying with NYSE Listing Rule 312.03, which covers share issues exceeding 20% of currently outstanding stock. Of 13,895,078 shares outstanding as of the December 18, 2025 record date, holders of 8,578,742 shares were present, constituting a quorum. The share issuance proposal passed with 8,153,269 votes for, 424,652 against and 821 abstentions, so no adjournment vote was needed. Completion of the merger still depends on satisfaction or waiver of the remaining closing conditions described in the merger agreement.

Positive

• Shareholders overwhelmingly approved the Third Coast share issuance needed to complete the Keystone merger, removing a major deal-condition tied to NYSE Rule 312.03.

Negative

• Dilution and execution risks remain, as the merger involves issuing additional common shares and is still subject to regulatory, legal and integration conditions before it can close.

Insights

Bank M&A and capital markets analyst

Shareholders cleared a key hurdle for Third Coast’s stock-funded acquisition of Keystone, though closing still depends on remaining conditions.

The vote authorizes Third Coast Bancshares, Inc. to issue additional common shares to Keystone stakeholders as consideration in the planned merger, including amounts exceeding 20% of currently outstanding shares under NYSE Listing Rule 312.03. This action aligns the company’s equity structure with the mechanics laid out in the merger agreement, a core requirement for completing an all‑ or mostly‑stock bank acquisition.

Support was strong: out of 8,578,742 shares represented at the special meeting, 8,153,269 backed the share issuance versus 424,652 against and 821 abstentions. That high approval rate reduces shareholder‑approval risk around the deal and moves the transaction forward. However, the merger still depends on satisfaction or waiver of remaining closing conditions in the merger agreement, and the company highlights typical risks such as regulatory approvals, integration challenges and dilution from issuing new shares, all of which will shape outcomes once the transaction is consummated.

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): January 23, 2026

THIRD COAST BANCSHARES, INC.

(Exact name of Registrant as Specified in Its Charter)

Texas			001-41028	46-2135597
(State or Other Jurisdiction of Incorporation)			(Commission File Number)	(IRS Employer Identification No.)
20202 Highway 59 North Suite 190
Humble, Texas				77338
(Address of Principal Executive Offices)				(Zip Code)

Registrant’s Telephone Number, Including Area Code: 281 446-7000

Not Applicable

(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:

☒	Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)
☐	Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)
☐	Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))
☐	Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Securities registered pursuant to Section 12(b) of the Act:

Title of each class		Trading Symbol(s)		Name of each exchange on which registered
Common stock, par value $1.00 per share		TCBX		New York Stock Exchange NYSE Texas

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 ☒

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. ☐

Item 5.07 Submission of Matters to a Vote of Security Holders.

On January 23, 2026, Third Coast Bancshares, Inc. (the “Company” or “Third Coast”) held a special meeting of shareholders (the “Special Meeting”) to consider certain proposals related to the Agreement and Plan of Reorganization, dated as of October 22, 2025 (the “Merger Agreement”), by and among the Company, Arch Merger Sub, Inc. (“Merger Sub”), and Keystone Bancshares, Inc. (“Keystone”), pursuant to which, subject to the satisfaction or waiver of certain conditions set forth in the Merger Agreement, Merger Sub will merge with and into Keystone (the “Merger”), with Keystone surviving as a wholly owned subsidiary of the Company.

As of December 18, 2025, the record date for shareholders entitled to notice of, and to vote at, the Special Meeting, there were 13,895,078 shares of common stock, par value $1.00 per share, of the Company (“Third Coast common stock”) issued and outstanding. The holders of 8,578,742 shares of Third Coast common stock were present in person or represented by proxy at the Special Meeting, constituting a quorum.

The following are the final results of the vote on the proposals considered and voted upon at the Special Meeting. For more information on each of these proposals, see the definitive joint proxy statement/prospectus filed by the Company with the U.S. Securities and Exchange Commission (the “SEC”) on December 19, 2025.

Proposal 1. To approve the issuance of shares of Third Coast common stock in connection with the Merger (including for purposes of complying with NYSE Listing Rule 312.03, which requires approval of the issuance of shares of Third Coast common stock in an amount that exceeds 20% of the currently outstanding shares of Third Coast common stock) (the “Third Coast Share Issuance Proposal”).

Votes For	Votes Against	Abstentions
8,153,269	424,652	821

There were no broker non-votes on the Third Coast Share Issuance Proposal. The Third Coast Share Issuance Proposal was approved by the requisite vote of the Company’s shareholders.

The Company’s shareholders did not vote on the proposal to adjourn or postpone the Special Meeting, if necessary or appropriate, to solicit additional proxies if there are insufficient votes at the time of such adjournment or postponement to approve the Third Coast Share Issuance Proposal, because such adjournment or postponement was not necessary.

Completion of the Merger remains subject to satisfaction or waiver of the closing conditions set forth in the Merger Agreement.

Forward-Looking Statements

This communication contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995 that are subject to risks and uncertainties and are made pursuant to the safe harbor provisions of Section 27A of the Securities Act of 1933, as amended, and Section 21E of the Securities Exchange Act of 1934, as amended. These forward-looking statements reflect Third Coast’s current views with respect to, among other things, future events and Third Coast’s financial performance and include, but are not limited to, the expected completion date, financial benefits and other effects of the proposed transaction. These statements are often, but not always, made through the use of words or phrases such as “may,” “should,” “could,” “predict,” “potential,” “believe,” “looking ahead,” “will likely result,” “expect,” “continue,” “will,” “anticipate,” “seek,” “estimate,” “intend,” “plan,” “projection,” “would” and “outlook,” or the negative version of those words or other comparable words or phrases of a future or forward-looking nature. These forward-looking statements are not historical facts, and are based on current expectations, estimates and projections about Third Coast’s industry, management’s beliefs and certain assumptions made by management, many of which, by their nature, are inherently uncertain and beyond Third Coast’s control. Accordingly, Third Coast cautions you that any such forward-looking statements are not guarantees of future performance and are subject to risks, assumptions and uncertainties that are difficult to predict. Although Third Coast believes that the expectations reflected in these forward-looking statements are reasonable as of the date made, actual results may prove to be materially different from the results expressed or implied by the forward-looking statements. There are or will be important factors that could cause Third Coast’s actual results to differ materially from those indicated in these forward-looking statements, including, but not limited to, the following: (1) the occurrence of any event, change or other circumstance that could give rise to the right of one or both of the parties to terminate the definitive merger agreement providing for the acquisition of Keystone by Third Coast; (2) the outcome of any legal proceedings that may be instituted against Third Coast or Keystone; (3) the possibility that the transaction does not close when expected or at all because required regulatory, shareholder or other approvals and other conditions to closing are not received or satisfied on a timely basis or at all (and the risk that such approvals may result in the imposition of conditions that could adversely affect the combined company or the expected benefits of the transaction); (4) the risk that the benefits from the transaction may not be fully realized or may take longer to realize than expected, including as a result of changes in, or problems arising from, general economic and market conditions, interest and exchange rates, monetary policy, laws and regulations and their enforcement, and the degree of competition in the geographic and business areas in which Third Coast and Keystone operate; (5)

disruption to the parties’ businesses as a result of the announcement and pendency of the transaction; (6) the risk that the integration of each party’s operations will be materially delayed or will be more costly or difficult than expected or that the parties are otherwise unable to successfully integrate each party’s businesses into the other’s businesses; (7) the possibility that the transaction may be more expensive to complete than anticipated, including as a result of unexpected factors or events; (8) reputational risk and potential adverse reactions of Third Coast’s or Keystone’s customers, suppliers, employees or other business partners, including those resulting from the announcement or completion of the transaction; (9) the dilution caused by Third Coast’s issuance of additional shares of its common stock in connection with the transaction; (10) a material adverse change in the financial condition of Third Coast or Keystone; (11) general competitive, economic, political and market conditions; (12) major catastrophes such as earthquakes, floods or other natural or human disasters, including infectious disease outbreaks; (13) the diversion of management’s attention and time from ongoing business operations and opportunities on merger-related matters; and (14) other factors that may affect future results of Third Coast and Keystone including changes in asset quality and credit risk, the inability to sustain revenue and earnings growth, changes in interest rates and capital markets, inflation, customer borrowing, repayment, investment and deposit practices, the impact, extent and timing of technological changes, capital management activities and other actions of the Board of Governors of the Federal Reserve System and legislative and regulatory actions and reforms. For a discussion of additional factors that could cause Third Coast’s actual results to differ materially from those described in the forward-looking statements, please see the risk factors discussed in Third Coast’s Annual Report on Form 10-K for the year ended December 31, 2024 filed with the SEC, and Third Coast’s other filings with the SEC.

The foregoing factors should not be construed as exhaustive and should be read together with the other cautionary statements included in this communication. If one or more events related to these or other risks or uncertainties materialize, or if Third Coast’s underlying assumptions prove to be incorrect, actual results may differ materially from what Third Coast anticipates. Accordingly, you should not place undue reliance on any such forward-looking statements. Any forward-looking statement speaks only as of the date on which it is made, and Third Coast does not undertake any obligation to publicly update or review any forward-looking statement, whether as a result of new information, future developments or otherwise. New factors emerge from time to time, and it is not possible for Third Coast to predict which will arise. In addition, Third Coast cannot assess the impact of each factor on its business or the extent to which any factor, or combination of factors, may cause actual results to differ materially from those contained in any forward-looking statements.

No Offer or Solicitation

This communication is being made in respect of the proposed merger transaction involving Third Coast and Keystone. This communication does not constitute an offer to sell or the solicitation of an offer to buy any securities or the solicitation of any vote or approval, nor shall there be any sale of securities in any jurisdiction in which such offer, solicitation or sale would be unlawful prior to registration or qualification under the securities laws of any such jurisdiction. No offer of securities shall be made except by means of a prospectus meeting the requirements of Section 10 of the Securities Act and otherwise in accordance with applicable law.

Important Additional Information and Where to Find It

In connection with the proposed merger transaction, Third Coast filed with the SEC a Registration Statement on Form S-4 on November 26, 2025, as amended on December 18, 2025 (the “Registration Statement”), which includes a prospectus of Third Coast and a joint proxy statement of Third Coast and Keystone. The Registration Statement was declared effective by the SEC on December 19, 2025, and on December 19, 2025, Third Coast filed a final prospectus with the SEC and its definitive proxy statement with the SEC. The Company commenced mailing the definitive joint proxy statement/prospectus to its shareholders and Keystone shareholders on or about December 23, 2025. Third Coast may also file other relevant documents with the SEC regarding the proposed merger transaction. This communication is not a substitute for the joint proxy statement/prospectus or Registration Statement or for any other document that Third Coast may file with the SEC and send to the shareholders of Third Coast or Keystone in connection with the proposed merger transaction.

INVESTORS AND SECURITY HOLDERS ARE URGED TO READ CAREFULLY THE REGISTRATION STATEMENT AND ACCOMPANYING JOINT PROXY STATEMENT/PROSPECTUS REGARDING THE PROPOSED MERGER TRANSACTION AND ANY OTHER RELEVANT DOCUMENTS FILED WITH THE SEC, AS WELL AS ANY AMENDMENTS OR SUPPLEMENTS TO THOSE DOCUMENTS, BECAUSE THEY CONTAIN OR WILL CONTAIN IMPORTANT INFORMATION.

Free copies of the Registration Statement and joint proxy statement/prospectus, as well as other filings containing information about Third Coast and the proposed transaction, may be obtained at the SEC’s Internet site (http://www.sec.gov). You will also be able to obtain the documents filed with the SEC by the Company, free of charge, at the Company’s website, https://ir.thirdcoast.bank/financials/sec-filings/. Alternatively, these documents, when available, can be obtained free of charge from Third Coast upon written request to Third Coast Bancshares, Inc., Attn: Investor Relations, 1800 West Loop South, Suite 800, Houston, TX 77027, or by calling (713) 960-1300.

Participants in the Solicitation

Third Coast, Keystone, their respective directors and executive officers and certain of their other members of management and employees may be deemed to be participants in the solicitation of proxies from Keystone’s shareholders and Third Coast’s shareholders in connection with the proposed transaction. Information about the directors and executive officers of Third Coast may be found in Third Coast’s Annual Report on Form 10-K for the year ended December 31, 2024, as filed with the SEC on March 5, 2025 and in Third Coast’s proxy statement for its 2025 Annual Meeting of Shareholders, as filed with the SEC on April 17, 2025, copies of which can be obtained free of charge from Third Coast or from the SEC’s website as indicated above. To the extent the holdings of Third Coast’s securities by its directors and executive officers have changed since the amounts set forth in Third Coast’s proxy statement for its 2025 Annual Meeting of Shareholders, such changes have been or will be reflected on Statements of Changes in Beneficial Ownership of Securities on Form 4 filed with the SEC. Additional information regarding the interests of these participants and other persons who may be deemed participants in the solicitation is included in the joint proxy statement/prospectus and other relevant materials that have been or may be filed with the SEC.

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.

			THIRD COAST BANCSHARES, INC.
Date:	January 23, 2026	By:	/s/ R. John McWhorter
			R. John McWhorter Chief Financial Officer

FAQ

What did Third Coast Bancshares (TCBX) shareholders approve at the special meeting?

Shareholders of Third Coast Bancshares, Inc. approved the issuance of additional shares of Third Coast common stock in connection with the planned merger with Keystone Bancshares, Inc., including for purposes of complying with NYSE Listing Rule 312.03 for issuances exceeding 20% of currently outstanding shares.

How did Third Coast Bancshares (TCBX) shareholders vote on the Keystone merger share issuance?

On the Third Coast share issuance proposal, shareholders cast 8,153,269 votes for, 424,652 votes against and 821 abstentions. There were no broker non‑votes, and the proposal was approved by the requisite shareholder vote.

How many Third Coast Bancshares (TCBX) shares were outstanding and represented at the special meeting?

As of the December 18, 2025 record date, there were 13,895,078 shares of Third Coast common stock outstanding. At the special meeting, holders of 8,578,742 shares were present in person or represented by proxy, which constituted a quorum.

Is the Keystone merger with Third Coast Bancshares (TCBX) now complete?

No. While the share issuance proposal was approved, completion of the merger between Third Coast and Keystone remains subject to satisfaction or waiver of the closing conditions set forth in the merger agreement, including required approvals and other specified conditions.

Why was NYSE Listing Rule 312.03 relevant to Third Coast Bancshares (TCBX)?

NYSE Listing Rule 312.03 requires shareholder approval when a company issues common stock in an amount that exceeds 20% of its currently outstanding shares. Third Coast’s proposal sought approval for the share issuance in connection with the Keystone merger to comply with this requirement.

What risks and uncertainties does Third Coast Bancshares (TCBX) highlight about the Keystone merger?

The company cites risks such as the possibility of termination of the merger agreement, outcomes of any legal proceedings, the chance the transaction may not close if approvals or conditions are not met, potential integration difficulties, increased costs, reputational impacts, a material adverse change at either company and dilution from issuing additional common shares.

Where can investors find more detailed information on the Third Coast–Keystone merger?

Investors can review the Registration Statement on Form S-4, the joint proxy statement/prospectus and related filings available for free on the SEC’s website at www.sec.gov and through Third Coast’s investor relations site at https://ir.thirdcoast.bank/financials/sec-filings/, as noted in the communication.