William P. Mayer

William P. Mayer

Partner Co-Chair, Financial Industry
William P. Mayer

Bill Mayer is a partner of the firm and co-chairs Goodwin’s Financial Industry Practice. He serves as corporate and regulatory counsel for financial institutions and financial institution holding companies, ranging from global and larger U.S. banking organizations to regional and community banks. As outside general counsel, he regularly advises banking organizations and their boards of directors on a broad array of corporate, regulatory, governance and transactional matters. Mr. Mayer also has participated in missions for USAID, the World Bank and the IMF to address financial sector issues in Eastern Europe, the Middle East and Latin America.

A former chair of Goodwin’s Pro Bono Committee for 10 years, Mr. Mayer maintains an active pro bono practice, serving on the board of KickStart International, a nonprofit devoted to designing and mass marketing appropriate technology to African farmers, and RefugePoint, a nonprofit organization founded to protect and develop solutions for refugees worldwide. He also serves as counsel and board advisor to Management Sciences for Health, PeaceFirst and the Penikese Island School.

With more than 35 years’ experience in the financial services industry, Mr. Mayer has been repeatedly listed in Chambers USA: America’s Leading Lawyers for Business, where clients and peers have lauded him for being “very effective at dealing with a board or with executive managementand noting that he “resolves problems in a sensible way and takes a balanced approach.

Professional Activities

Mr. Mayer serves on the banking law committees of the Boston and American Bar Associations, and is a member of state banker associations in Massachusetts, Maine, Vermont, New Hampshire, Rhode Island, Connecticut, New York and California.

Professional Experience

Mr. Mayer has taught bank and bank holding company mergers and acquisitions at Boston University School of Law, and serves on the Board of Advisors for its Center for Finance, Law & Policy. Following law school graduation, Mr. Mayer served as law clerk for the Honorable William H. Timbers, U.S. States Court of Appeals for the Second Circuit.


Mr. Mayer is nationally ranked in Chambers USA: America's Leading Lawyers for Business for his financial institutions M&A work. He is also ranked in U.S. News-Best Lawyers, which has selected him as Boston’s banking and finance “Lawyer of the Year” (2016)While in law school, Mr. Mayer was an editor of the Virginia Law Review.

Areas of Practice


Mr. Mayer handles a wide variety of transactions for Goodwin’s banking and financial services clients, including mergers, acquisitions, public and private offerings of debt and equity securities, stock conversions, bank and holding company formations, and other reorganizations of financial institutions and holding companies. He also regularly advises foreign and U.S. clients on bank regulatory matters involving the Federal Reserve Board, the Federal Deposit Insurance Corporation, the Comptroller of the Currency, and other state and federal regulatory agencies.

Over the past several years, Mr. Mayer has advised a wide range of financial institution clients on capital and compliance matters arising under the Dodd-Frank Act, the Basel Accords and other regulations, and has counseled institutional and other investors with respect to transactions involving banks and bank holding companies. Mr. Mayer also advises other business clients, nonprofits and individuals on a wide range of corporate, corporate governance and other legal matters. His recent work includes representing and/or advising:

  • Boston Private Financial Holdings in connection with a variety of east coast and west coast business combinations, and most recently with respect to the sale by Carlyle Group of its post financial crisis ownership interest, and the consolidation of its banking operations
  • Brookline Bancorp on a number of M&A transactions including its acquisition of Bancorp Rhode Island, Inc. and First Ipswich Bancorp
  • Camden National Corporation in connection with the expansion of its Maine-based banking franchise, including its recent acquisition of Bank of America’s Maine branch network
  • HarborOne Credit Union with respect to its conversion to a Massachusetts chartered cooperative bank, the first such transaction in the Commonwealth
  • Eastern Bank Corporation in connection with its acquisition of Campello Bancorp, a troubled financial institution in Brockton, MA
  • Northeast Bancorp in connection with its restructuring and recapitalization by private equity and other investors as well as its follow-on public offering of common stock



J.D., 1977
University of Virginia School of Law
M.S., 1974
University of Dar es Salaam
A.B., 1973
Dartmouth College

(summa cum laude)


1977 to 1978 U.S. Court of Appeals for the Second Circuit, Honorable William H. Timbers



District of Columbia


U.S. Court of Appeals for the District of Columbia Circuit
U.S. District Court for the District of Columbia
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