Peter A. Spaeth

Special Counsel

Spaeth, Peter A.

Peter Spaeth's practice focuses on securities and antitrust matters. For three decades, he has represented a variety of corporations, as well as their officers and directors, in securities fraud class actions, shareholder derivative suits, merger litigation, complex antitrust class actions and other suits, government investigations, and a variety of other commercial litigations and arbitrations. Mr. Spaeth has extensive experience in briefing a range of sophisticated and difficult legal issues at all stages of litigation. He has been a principal author of countless briefs filed in federal and state trial and appellate courts throughout the country, including the Supreme Court of the United States. He has helped secure dismissal of numerous securities fraud class actions and shareholder derivative suits, among others

Mr. Spaeth's clients in securities matters have included Apollo Education Group, Aveo Pharmaceuticals, BJ's Wholesale Club, Cynosure, Endurance International Group, Intercept, Invivo Therapeutics, Kior, The Medicines Company, Medtronic, MKS Instruments, Primus Telecommunications, Sonus Networks, Staples, State Street Corporation, Tetraphase Pharmaceuticals, Theranos and Transkaryotic Therapies. His antitrust clients have included American Tower Corporation, Analog Devices, Avid Technologies, Baker Hughes, Cephalon, IDEXX Laboratories, National Grid USA., Northern Telecom, Ocean Spray, Prime Computer and Thermo Electron Corporation.

Publications & News


March 16, 2018

Principles of Antitrust Causation Are Alive and Well[butrin]: Why the Third Circuit Got It Right

An article by Margaret O'Grady and Peter Spaeth, published in Bloomberg Law's Antitrust & Trade Regulation Report. The Supreme Court's decision in FTC v Actavis Inc. opened the door to antitrust lawsuits based on "reverse payments." A separate appeals court decision, In re Wellbutrin Antitrust Litigation, could make it more difficult to assign damages in reverse payment cases. Ms. O'Grady and Mr. Spaeth explore how the two opinions can coexist.

August 30, 2017

District Court Rejects Direct Purchaser Class for Failure to Satisfy Numerosity Requirement

On August 28, 2017, in King Drug Company of Florence, Inc., et al. v. Cephalon, Inc., et al., the Eastern District of Pennsylvania denied class certification for direct purchasers asserting Hatch-Waxman reverse-payment antitrust claims because the 24-25 putative class members did not satisfy the numerosity requirement.

March 13, 2017

Death Knell to Merger Litigation for Massachusetts Corporations?

In IBEW Local No. 129 Benefit Fund v. Tucci, the Massachusetts Supreme Judicial Court (SJC) affirmed the dismissal of direct claims for breach of fiduciary duty by EMC shareholders challenging the merger of EMC and Dell, Inc. This WilmerHale Client Alert was republished in Bloomberg BNA's Mergers & Acquisitions Law Report.

November 3, 2016

Third Circ. Weighs In On Product-Hopping

An article by Mark Ford, Peter Spaeth and Benjamin Ernst, published by Law360, discusses the Third Circuit weighing in on product-hopping in relation to the Mylan Pharmaceuticals Inc. v. Warner Chilcott Public Limited Co. affirmation among others.

September 29, 2016

Doryx: Third Circuit Affirms Dismissal of Product Hopping Claim

On September 28, 2016, in Mylan Pharmaceuticals Inc. v. Warner Chilcott Public Limited Co. (Doryx), the Third Circuit affirmed the lower court's grant of summary judgment against antitrust claims by generic manufacturer Mylan regarding branded manufacturer Warner Chilcott's alleged “product hopping” activity with respect to its drug Doryx (delayed-release doxycycline hyclate).

January 27, 2015

Global Anti-Bribery Year-in-Review: 2014 Developments and Predictions for 2015

The year 2014 witnessed several notable developments in the enforcement of the Foreign Corrupt Practices Act. In Global Anti-Bribery Year-in-Review: 2014 Developments and Predictions for 2015, WilmerHale attorneys discuss notable trends and developments in 2014, and look ahead to possible trends in 2015.

December 5, 2014

Provigil and Nexium: Conflicting Conclusions About Accelerated Entry Provisions in Hatch-Waxman Settlements

An article by Mark Ford, Peter Spaeth and Dana Burwell, published in the December 2014 edition of Bloomberg BNA's Pharmaceutical Law & Industry Report, Vol. 12, No. 1659.

June 18, 2013

FTC v. Actavis: Supreme Court Adopts Rule of Reason for “Reverse Payment” Settlements

On June 17, 2013, the Supreme Court decided Federal Trade Commission v. Actavis, Inc., No. 12-416, by a 5-3 vote (Justice Alito recused), resolving a circuit split over the appropriate antitrust standard to apply when evaluating "reverse payment" Hatch-Waxman patent litigation settlements between branded and generic pharmaceutical companies.

December 9, 2009

WilmerHale Announces 2010 Promotions

WilmerHale is pleased to announce the firm's 2010 elevations, which will become effective on January 1, 2010. A full list of elevated partners and special counsel can be found at the end of this press release.

February 1, 2007


A quarterly newsletter addressing current regulatory, intellectual property and antitrust issues facing pharmaceutical companies in the US, Europe and China.

Professional Activities

Mr. Spaeth is a member of the American Bar Association and the Massachusetts Bar Association.


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JD, cum laude, Harvard Law School, 1985

BA, summa cum laude, University of Michigan, 1980

Bar Admissions


District of Columbia

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