William (Bill) M. Regan | New York | Hogan Lovells

William (Bill) M. Regan

Partner Litigation, Arbitration, and Employment

Regan William

William (Bill) M. Regan
Regan William
  • Overview
  • Experience
  • Credentials
  • Insights and events

Bill Regan understands that success in litigation means obtaining early-stage resolutions that save clients the substantial burden, expense, and distraction of protracted legal disputes.

To achieve this goal, Bill begins each case by working closely with the client to marshal the critical facts and efficiently and compellingly present the client's legal position to the court or regulator as early as possible. This intensive "up-front" approach to litigation regularly results in pleading-stage dismissals and terminated regulatory investigations.

Bill is a partner in Hogan Lovells' Securities, Shareholder and M&A Litigation group. He has more than 20 years of experience representing public and private companies in all types of securities litigation matters, including class actions under the Securities Act of 1933 and the Securities Exchange Act of 1934, stockholder derivative suits, SEC and FINRA investigations, internal and special committee investigations, and M&A and corporate governance disputes. Bill's securities litigation matters have involved corporate culture and #metoo allegations, accounting improprieties, missed earnings forecasts, regulatory violations, and representations concerning FDA approval of new drug applications. In the M&A space, Bill has represented clients in cases concerning false statements in proxy and tender offer disclosures, indemnification in connection with representation and warranty breaches, earn-out disputes, purchase price adjustments, and material adverse change issues.

In addition to his work for public and private issuers, Bill regularly represents financial institutions on securities-related matters. Recently, Bill has represented some of the world's largest international financial services firms in U.S. legal proceedings concerning repurchase agreements, CMBS, RMBS, hedge-fund linked derivatives, futures, commercial credit facilities, trading accounts, and real estate and construction loans.

Representative experience

Representing international investment bank in a litigation concerning repo liquidations and RMBS valuation during the financial crisis.
Represented international investment bank in multiple litigations concerning hedge-fund linked derivatives.
Obtained dismissal of derivative action against a financial institution alleging breach of fiduciary duty and improper liquidation of loan collateral.
Represented commercial bank and senior executives in SEC investigation of timely recognition of loan losses during the financial crisis.
Represented international software firm in SEC investigation concerning accounting misconduct identified by corporate whistleblower.
Obtained dismissal of SDNY securities class action against officers and directors of clean energy company.
Obtained dismissal of DNJ securities class action against pharmaceutical firm following FDA rejection of new drug application.
Represented issuer in SDNY securities class action filed after executive turnover, failure to file SEC reports, and resignation by independent auditor.


  • B.A., Hofstra University, magna cum laude
  • J.D., The George Washington University Law School, with honors
Bar admissions and qualifications
  • New York
Court admissions
  • U.S. District Court, Eastern District of New York
  • U.S. District Court, Southern District of New York


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