Billy Marsh
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Billy Marsh

Associate

Billy handles high-stakes litigation and investigations and is called upon by clients for their most important legal matters. He has specific expertise in shareholder and securities litigation and mass tort and product liability litigation, where he has obtained noteworthy victories for his clients.
For example, Billy achieved a complete defense verdict in an arbitration brought by a bankruptcy litigation trustee seeking over $600 million in damages for alleged breaches of fiduciary duty. He successfully defended Twitter in shareholder actions seeking to halt the $44 billion acquisition of the company by Elon Musk. And the American Lawyer recognized Billy in its Litigator of the Week Series for his work on behalf of a global chemical company in fending off litigation from the State of Maine, seeking to hold the company liable for environmental contamination caused by per- and polyfluoroalkyl substances (PFAS) across the state.

Clients have praised Billy as “super smart, capable, thoughtful, and responsive” and appreciate Billy’s quick grasp of their business and practical approach.

Expertise

Experience

Representative matters

Shareholder and Securities Litigation

  • Obtained complete defense verdict denying all claims in arbitration brought by a bankruptcy litigation trustee alleging claims of breach of fiduciary duty against former public company CFO and seeking over $600 million in damages.
  • Defended Twitter in shareholder class actions arising from $44 billion acquisition by Elon Musk and secured dismissal of action in Delaware Chancery Court seeking to enjoin the transaction.
  • Obtained partial dismissal of securities class action and full dismissal of derivative action filed against an online real estate services company, its directors and officers, and Chamath Palihapitiya, among others, relating to de-SPAC merger between the company and SPAC entity backed by Social Capital.
  • Defended an international chemical manufacturer against parallel putative class actions pending in federal and Texas state court alleging violations of the Securities Act of 1933 and Securities Exchange Act of 1934 in connection with two public stock offerings.
  • Obtained dismissal of securities class action and related derivative actions filed against Tenet Healthcare and its directors and officers, arising from a regulatory proceeding, and successfully defended dismissal of derivative actions on appeal.
  • Defended an oilfield services company against securities class actions in Colorado state and federal courts that alleged misstatements in connection with the company’s initial public offering.
  • Successfully defended T. Boone Pickens, BP Capital Management, and related defendants in securities case alleging misrepresentations regarding hedge fund strategy.
  • Defended consumer finance company and its directors and officers in two securities class actions challenging disclosures related to compliance with the Federal Reserve’s CCAR program and alleged accounting misstatements.
  • Obtained dismissal of several shareholder derivative suits filed against the board of directors of AT&T.
  • Represented Sanchez Resources, LLC (a privately held oil and gas exploration company) and its president in shareholder derivative litigation before the Delaware Court of Chancery.
  • Counsel for Washington Legal Foundation in submission of amicus curiae briefs to Supreme Court of the United States on several significant securities litigation matters, including Macquarie Infrastructure Corp. v. Moab Partners, L. P., 601 U.S. 257 (2024).

Mass Tort and Product Liability Litigation

  • Secured dismissal of litigation brought by the State of Maine seeking to hold a global chemical company liable for environmental contamination from per- and polyfluoroalkyl substances (PFAS) throughout the state.
  • Defeated class certification for National Football League in lawsuit alleging claims of breach of contract and fraud against the NFL and the Dallas Cowboys for allegedly not providing prescribed seats to Super Bowl XLV ticketholders. Defeated individual plaintiffs’ fraud claims at jury trial.
  • Defeated class action bid for AT&T in a suit brought by property owners alleging that AT&T telephone cable buried underneath their properties — pursuant to easements that had been granted to AT&T in the 1950s — were contaminating their properties.
  • Secured dismissal of wrongful death claims brought against Dow allegedly arising from exposure to PFAS.
  • Defense of Dow in numerous PFAS-related lawsuits consolidated in the aqueous fire-fighting foam (AFFF) multi-district litigation in South Carolina.
  • Defense of PolyPipe/Dura-Line, one of the nation’s largest manufacturers of the plastic pipes that are used by utilities and operators in their natural gas distribution networks, in the investigation and disclosure of a manufacturing issue and in related litigation matters.
  • Defended manufacturer of water filtration systems in nationwide consumer class action relating to alleged breaches of warranty and false advertising.
  • National coordinating counsel in product liability lawsuits asserted throughout the United States against a major manufacturer of highway products.
  • Advised car parts manufacturer on reporting obligations and risks relating to potential product defect.
  • Trial counsel for group of intervening energy companies in bankruptcy adversary proceeding relating to validity of $1.1 billion in payments made pursuant to ERCOT pricing orders during Winter Storm Uri.
  • Defense of global manufacturing company in a federal class action and numerous state mass actions alleging manufacturing and design defects in domestic plumbing products.
  • Representation of publicly traded chemicals company in internal assessment of global use of PFAS and associated risks.

Complex Litigation

  • Trial counsel for a multinational mass media and entertainment conglomerate and Simon & Schuster in DOJ action to enjoin $2.2 billion sale of Simon & Schuster to Penguin Random House.
  • Trial counsel for The Williams Companies in bankruptcy adversary proceeding to uphold gas gathering agreements involving $895 million in MVC deficiency payments.
  • Defense of medical billing company in consumer class action alleging statutory and common law claims regarding the company’s billing practices.

Government Investigations, Regulatory Counseling, and Compliance

  • Internal investigation of alleged misconduct on part of Founder and Chairman of multi-billion dollar private company and provide recommendations on fiduciary duties and corporate governance.
  • Internal investigation of alleged accounting fraud involving public company and preparation of report for audit committee regarding findings and disclosure obligations.
  • Internal investigation of whistleblower allegations regarding healthcare fraud and advised special committee on findings and recommendations.
  • Internal investigation of compliance with FHWA regulations and prepare report and presentation on findings for FHWA.
  • Representation of Plastics Executive in Criminal Antitrust Investigation.
  • Representation of Financial Services Executives in CFPB Investigation.
  • Representation of Fund Manager in SEC Investigation.
  • Counseled large industry organization on compliance with FinCEN regulations.
  • Counseled government contractor on compliance with gifting and ethics laws.
  • Counseled large beverage distributor on antitrust compliance.
  • Represented high-level university administrator in connection with internal investigation of admissions fraud and alleged discriminatory practices.

Pro bono

Billy has represented immigrants in U.S. asylum proceedings and consistently volunteers his time to assist immigrants in obtaining legal advice relating to their immigration status.

Published Work

  • Marsh, Billy (2021) "Protecting Board Communication Privilege," The Corporate Board 
  • Marsh, Billy (2016) "Compliance Post Affordable Care Act," New Perspectives of Healthcare Risk Management, Control and Government     
  • Marsh, Billy (2016) "Antitrust and Business Litigation," Texas Bar Journal     

Speaking Engagements

  • Presenter, Developing Effective Compliance and Audit Committees, Clear Law Institute, May 2016

Leadership Positions And Professional Affiliations

  • J. Reuben Clark Law Society, Board Member for DFW Chapter

Qualifications

Admissions

Attorney-at-Law, State of Texas, US

Registered Foreign Lawyer, England and Wales, 2024

Courts

United States District Court for the Northern District of Texas

United States District Court for the Southern District of Texas

United States District Court for the Western District of Texas

Academic

BS, cum laude, Brigham Young University 

JD, University of Virginia School of Law

Languages

Spanish
Disclaimer
A&O Shearman was formed on May 1, 2024 by the combination of Shearman & Sterling LLP and Allen & Overy LLP and their respective affiliates (the legacy firms). Any matters referred to above may include matters undertaken by one or more of the legacy firms rather than A&O Shearman.