Umpqua Holdings Corporation (NasdaqGS:UMPQ) entered into a definitive agreement to acquire Columbia Banking System, Inc. (NasdaqGS:COLB) for $5.1 billion in a reverse merger transaction on October 11, 2021. Umpqua shareholders will receive 0.5958 of a share of Columbia stock for each Umpqua share they own. Upon completion of the transaction, Umpqua shareholders will own approximately 62% and Columbia shareholders will own approximately 38% of the combined company. The combined holding company will operate under the Columbia Banking System, Inc. name and will be headquartered in Tacoma, Washington. As a part of acquisition, Merger Sub will merge with and into Umpqua, with Umpqua as the surviving entity, and immediately following such merger, Umpqua will merge with and into Columbia, with Columbia as the surviving corporation The combined bank will operate under the Umpqua Bank name and will be headquartered in the greater Portland metropolitan area. In connection with this proposal, Columbia also has filed with the Board an election to become a financial holding company pursuant to sections 4(k) and (l) of the BHC Act and section 225.82 of the Board's Regulation Y. Other major subsidiaries and divisions will include Columbia Trust Company, CB Financial Services and Columbia Private Bank, which will operate under the banner of Columbia Wealth Management, as well as Financial Pacific Leasing, Inc. The combined company will trade under Columbia's ticker symbol (COLB) on the Nasdaq Stock Market. In the event of termination, Umpqua shall pay Columbia and Columbia shall pay termination fee of $145 million.

The combined company will be led by an executive team composed of leaders from both Columbia and Umpqua. Cort O'Haver, President and Chief Executive Officer of Umpqua, will serve as the Executive Chairman and Clint Stein, President and Chief Executive Officer of Columbia, will serve as Chief Executive Officer. Chris Merrywell will serve as President of Consumer Banking, Tory Nixon as President of Commercial Banking, and Ron Farnsworth as Chief Financial Officer. Upon closing of the transaction, the combined company's board will consist of seven directions from each of Columbia and Umpqua with Craig Eerkes, the current Chairman of Columbia, serving as the Lead Independent Director.

The transaction is subject to satisfaction of customary closing conditions, including NASDAQ listing, Federal Reserve Board, Federal Deposit Insurance Corporation and Oregon and Washington state bank regulators approvals, S-4 shall have become effective under the Securities Act and no stop order suspending the effectiveness of the S-4 shall have been issued and no proceedings for such purpose shall have been initiated or threatened by the SEC and not withdrawn, receipt of regulatory approvals and approvals from each company's shareholders. Special meeting of holders of Columbia common stock will be held on January 26, 2022. Columbia Banking System and Umpqua Holdings Corporation received Shareholder approvals on January 26, 2021. The transaction was unanimously approved by the Boards of Directors of Umpqua and Columbia. As of December 3, 2022, as of December 3, 2021, three purported holders of Umpqua common stock had filed complaints relating to the proposed transaction in the U.S. District Court for the Southern District of New York. As of September 17, 2022, Columbia and Umpqua entered into a Letter of Agreement with the Department of Justice, Antitrust Division. Pursuant to the LOA, as a condition to obtaining regulatory approvals necessary to complete the transaction, the Parties will be required to divest ten Columbia State Bank branches located in Colusa and Glenn counties in California; Lincoln, Malheur and Tillamook counties in Oregon; and Klickitat county in Washington. On October 25, 2022, the Board of Governors along with Ann E. Misback of the Federal Reserve Board unanimously approved the transaction. The Fed and Department of Justice considered the anti-competitive angle should the merger go through. Columbia and Umpqua have also received required regulatory approvals from the Oregon Department of Consumer and Business Services and the Washington Department of Financial Institutions with respect to the transaction. As of January 9, 2023, Federal Deposit Insurance Corporation (the "FDIC") has approved the transaction. The FDIC approval was the final outstanding regulatory approval necessary to complete the combination. The transaction is expected to close in mid-2022. As of July 21, 2022, the transaction is expected to close in third quarter 2022. The merger is expected to be completed by the end of February, subject to the satisfaction or waiver of the remaining closing conditions set forth in the merger agreement governing the transaction. The transaction is projected to deliver approximately 25% cash EPS accretion and 23% GAAP EPS accretion to Columbia, and approximately 11% cash EPS accretion and 8% GAAP EPS accretion to Umpqua in 2023.

Keefe, Bruyette & Woods acted as financial advisor and a fairness opinion provider to Columbia. Mark J. Menting and Patrick S. Brown, Heather L. Coleman, Nader A. Mousavi, David C. Spitzer and Joseph J. Matelis from Sullivan & Cromwell LLP is serving as legal counsel to Columbia. J.P. Morgan Securities LLC is serving as financial advisor and a fairness opinion provider to Umpqua. Edward D. Herlihy from Wachtell, Lipton, Rosen & Katz is serving as a legal counsel to Umpqua. Simpson Thacher & Bartlett LLP represented J.P. Morgan Securities LLC as financial advisor to Umpqua Holdings. Lee Meyerson, Sebastian Tiller and Stephen Wiseman from Simpson Thacher acted as counsel. Okapi Partners LLC acted as an information agent to Columbia. D.F. King & Co., Inc. acted as an information agent to Umpqua. Broadridge Financial Solutions, Inc. acted as a transfer agent to Columbia. Columbia will pay a fee of $25,000 to Okapi Partners. Umpqua will pay a fee of $0.02 million to D.F. King & Co. Columbia agreed to pay Keefe, Bruyette & Woods a total cash fee of $28 million, $3 million of which became payable to KBW with the rendering of KBW's opinion and the balance of which is contingent upon the closing of the first merger. Umpqua has agreed to pay J.P. Morgan a fee of $36 million, $5 million of which became payable upon the delivery of J.P. Morgan's opinion and the remainder of which will become payable only upon consummation of the mergers.

Umpqua Holdings Corporation (NasdaqGS:UMPQ) completed the acquisition of Columbia Banking System, Inc. (NasdaqGS:COLB) in a reverse merger transaction on February 28, 2023. Shares of Umpqua ceased trading prior to the opening of the Nasdaq Stock Market on March 1, 2023.