Material Event (Form 8-K)

Item 8.01

Other Events.

As previously disclosed, Synovus Financial Corp., a Georgia corporation ("Synovus") entered into an Agreement and Plan of Merger (the "Merger Agreement"), dated as of July 24, 2025, with Pinnacle Financial Partners, Inc., a Tennessee corporation ("Pinnacle") and Steel Newco Inc., a Georgia corporation jointly owned by Synovus and Pinnacle ("Newco"). The Merger Agreement provides that, upon the terms and subject to the conditions set forth therein, Synovus and Pinnacle will each simultaneously merge with and into Newco (such mergers, collectively, the "Merger"), with Newco continuing as the surviving corporation in the Merger and named Pinnacle Financial Partners, Inc. Upon the terms and subject to the conditions set forth in the Merger Agreement, immediately following the effective time of the Merger (the "Effective Time"), Pinnacle Bank, a Tennessee-chartered bank ("Pinnacle Bank"), will become a member bank of the Federal Reserve System (the "FRS Membership"), and immediately following the effectiveness of the FRS Membership, Synovus Bank, a Georgia-chartered bank ("Synovus Bank"), will merge with and into Pinnacle Bank (the "Bank Merger"), with Pinnacle Bank continuing as the surviving bank in the Bank Merger. The Merger Agreement was unanimously approved by the boards of directors of each of Synovus, Pinnacle and Newco.

In connection with the proposed Merger, Newco filed with the Securities and Exchange Commission (the "SEC") a registration statement on Form S-4, as amended, to register the shares of Newco common stock that will be issued to Synovus shareholders and Pinnacle shareholders in connection with the Merger. The registration statement contains a joint proxy statement of Synovus and Pinnacle that also constitutes a prospectus of Newco. The registration statement was declared effective on September 30, 2025. Newco filed a prospectus on September 30, 2025, and Synovus and Pinnacle each filed a definitive proxy statement on September 30, 2025. Synovus and Pinnacle each commenced mailing of the definitive joint proxy statement/prospectus (the "joint proxy statement/prospectus") to their respective stockholders on or about September 30, 2025.

Synovus and Pinnacle will each hold a special meeting of stockholders on November 6, 2025 to consider certain proposals related to the Merger Agreement as further described in the joint proxy statement/prospectus.

Litigation Related to the Mergers

Following the announcement of the Merger Agreement, as of the date of this Current Report on Form 8-K, three lawsuits challenging the Merger have been filed (each, a "Lawsuit" and, collectively, the "Lawsuits"). The first Lawsuit, captioned Drulias v. Abney Boxley, III et al.(No. 25-1439-I), was filed in Tennessee Chancery Court on October 14, 2025. The second Lawsuit, Weissv. Synovus Financial Corp. et al.(No. 659143/2025) was filed in New York Superior Court on October 15, 2025. The third Lawsuit, Jonesv. Synovus Financial Corp. et al.(No. 659151/2025) was filed in New York Superior Court on October 16, 2025. In addition, Synovus and Pinnacle have received demand letters from counsel representing purported stockholders of Synovus or Pinnacle, respectively (the "Demand Letters" and, together with the Lawsuits, the "Matters"). The Matters each allege that, among other things, the joint proxy statement/prospectus contains certain disclosure deficiencies and/or incomplete information regarding the Merger.

Synovus and Pinnacle believe that the claims asserted in the Matters are without merit and supplemental disclosures are not required or necessary under applicable laws. However, in order to avoid the risk that the Matters delay or otherwise adversely affect the Merger, and to minimize the costs, risks and uncertainties inherent in litigation, and without admitting any liability or wrongdoing, Synovus, Pinnacle and Newco are supplementing the joint proxy statement/prospectus as described in this Current Report on Form 8-K. Nothing in this Current Report on Form 8-K shall be deemed an admission of the legal necessity or materiality under applicable laws of any of the disclosures set forth herein. To the contrary, Synovus, Pinnacle and Newco specifically deny all allegations in the Matters that any additional disclosure was or is required.

Supplemental Disclosures to the Joint Proxy Statement/Prospectus

The additional disclosures (the "supplemental disclosures") in this Current Report on Form 8-K supplement the disclosures contained in the joint proxy statement/prospectus and should be read in conjunction with the disclosures contained in the joint proxy statement/prospectus, which should be read in its entirety. To the extent that information set forth in the supplemental disclosures differs from or updates information contained in the joint proxy statement/prospectus, the information in this Current Report on Form 8-K shall supersede or supplement the information contained in the joint proxy statement/prospectus. All page references are to the joint proxy statement/prospectus and terms used but not otherwise defined herein shall have the meanings ascribed to such terms in the joint proxy statement/prospectus. For clarity, new text within restated paragraphs and tables from the joint proxy statement/prospectus is underlined, while deleted text is stricken-through.

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Centerview reviewed analyst share price targets for Synovus common stock in recently published, publicly available research analysts' reports, with share price targets ranging from $55.00 to $70.00 and a median share price target of $62.00.

Centerview reviewed analyst share price targets for Pinnacle common stock in recently published, publicly available research analysts' reports, with share price targets ranging from $117.00 to $145.00 and a median share price target of $130.00.

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Morgan Stanley performed a public trading comparables analysis for each of Synovus and Pinnacle, which is designed to provide an implied trading value of a company by comparing each of Synovus and Pinnacle to a group of selected companies with similar characteristics to Synovus and Pinnacle, respectively. Morgan Stanley compared certain financial information of Synovus and Pinnacle with publicly available information for the applicable group of selected companies 18 U.S. publicly-traded banks or bank holding companies (the "Selected Companies") that had assets between $35 billion and $85 billion, but excluding specialty finance companies and Puerto Rican banksdescribed below. The selected companies were chosen based on Morgan Stanley's knowledge of the industry and because these companies have businesses that may be considered similar to the business of Synovus or Pinnacle, respectively.

The group of selected companies ("Selected Companies") consisted of the following U.S. publicly-traded banks or bank holding companies that had assets between $35 billion and $85 billion, but excluding specialty finance companies and Puerto Rican banks:

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The following table presents the results of this analysis:

With respect to the Selected Companies, Synovus and Pinnacle, Morgan Stanley reviewed:

In all instances, multiples were based on closing stock prices on July 21, 2025. Financial and market data for the Selected Companies were based on the most recent publicly available information and mean equity research consensus estimates. Financial information for Synovus and Pinnacle was based on the Street Forecasts.

The following table presents the results of this analysis:

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Morgan Stanley based its analysis on a range of terminal forward multiples of 9.4x to 11.4x to the terminal year 2030 estimated forward earnings (determined based on considerations Morgan Stanley deemed relevant in its professional judgment)and a range of discount rates of 11.1% to 13.1% (determined using the capital asset pricing model and utilizing inputsbased on considerations Morgan Stanley deemed relevant in its professional judgment including a market risk premium, a risk-free rate of return and predicted beta). Based on information provided by Synovus management, Morgan Stanley also assumed a 4.5% opportunity cost of cash. Utilizing the foregoing range of discount rates and terminal value multiples, Morgan Stanley derived a range of implied present values per share of Synovus common stock of $50.50 to $61.50.

Morgan Stanley based its analysis on a range of terminal forward multiples of 13.3x to 15.3x to the terminal year 2030 estimated forward earnings (determined based on considerations Morgan Stanley deemed relevant in its professional judgment)and a range of discount rates of 10.5% to 12.5% (determined using the capital asset pricing model and utilizing inputsbased on considerations Morgan Stanley deemed relevant in its professional judgment including a market risk premium, a risk-free rate of return and predicted beta). Based on information provided by Synovus management, Morgan Stanley also assumed a 4.5% opportunity cost of cash. Utilizing the foregoing range of discount rates and terminal value multiples, Morgan Stanley derived a range of implied present values per share of Pinnacle common stock of $107.25 to $130.00.

Morgan Stanley reviewed and analyzed the estimated impact of the merger on (a) projected earnings per share for holders of Pinnacle common stock for 2026, including fully phased in cost synergies, but excluding costs associated with the merger, (b) projected earnings per share for holders of Pinnacle common stock for 2027, including fully phased in cost synergies, but excluding costs associated with the merger as described under "-Certain Unaudited Prospective Financial Information-Certain Estimated Synergies Attributable to the Merger", (c) the tangible book value per share of Pinnacle common stock as of the closing date, and (d) Pinnacle's common equity Tier 1 ratio as of the closing date and, in each case, based on the Street Estimates. This analysis indicated that the merger would be accretive to Pinnacle's 2026E earnings per share and 2027E earnings per share by approximately 24% and 21%, respectively,and dilutive to Pinnacle's tangible book value per share and common equity Tier 1 ratio by approximately 9% and 131 basis points, respectively. Any such estimates are not indicative of future results or actual values, which may be significantly more or less favorable than those suggested by the estimates.