David Manspeizer advocates for, and advises clients on, challenging intellectual property (IP) issues and disputes, focusing on the biotechnology and pharmaceutical sectors. Drawing on his seven and a half years as head of IP at Wyeth, where he was responsible for all of the company’s IP matters, David brings a unique understanding of the issues that in-house counsel face, and provides real-world, practical advice to clients and colleagues. David has more than 25 years of experience counseling and representing industry-leading global pharmaceutical and biotechnology companies in complex patent litigation. He leads litigation teams in Hatch-Waxman and other litigation for branded pharmaceutical and biotech companies; counsels clients on due diligence, portfolio reviews, validity and infringement issues, licensing and other transactional matters, including settlements; and provides strategic patent portfolio advice. David is passionate about devising appropriate strategies to define and achieve the client’s business objectives. He has also served as an expert witness on licensing issues in the pharmaceutical and biotech industries and as a technical advisor to the Honorable R. Gilstrap in the US District Court for the Eastern District of Texas.

    David began his career as an intellectual property litigator at an international intellectual property law firm. There, he handled pharmaceutical and biotechnology patent litigation in US district courts, the US Court of Appeals for the Federal Circuit and the US International Trade Commission.

    David was appointed Vice-President of Intellectual Property and Associate General Counsel at Wyeth in 2002, leading a 140-person department responsible for the company’s patent, trademark, copyright and trade secrets matters, including all of its IP litigation matters. David supervised diligence, counseling, strategy, IP aspects of transactions, and public policy for the corporate and pharmaceutical, consumer, and animal health divisions. David also managed multiple concurrent US and foreign patent and trademark litigations, including Hatch-Waxman and other litigation concerning the company’s blockbuster Effexor® XR, Protonix® and Enbrel® products. He led the effort that resulted in the Federal Circuit’s Wyeth v. Kappos decision, while directing a strategic patent portfolio focus that yielded the top ranking on The Wall Street Journal’s patent scorecard for eight consecutive quarters (2007 – 2009).

    After Wyeth’s acquisition in late 2009, and prior to joining the firm, David was a partner in the IP litigation practice of two global law firms.

    David was named an “IP Star” by Euromoney Legal Media Group’s Managing IP (2014 – 2016 and 2018 – 2019) and by LMG Life Sciences (2018 – 2019). He is also recommended by The Legal 500 US (2017) in Patent Litigation, a New York Super Lawyer for IP Litigation (2014 – 18) and a JD Supra 2019 Readers Choice Award winner for Life Sciences.

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    • Defended client pharmaceutical companies in multiple litigations regarding “Classen” patents. Cases were each dismissed as claimed infringing activity was exempt under section 271(e)(1). The Federal Circuit affirmed under Rule 36 both times.
    • Represented an innovator client in Hatch-Waxman litigation regarding prescription anti-HIV medication. Multiple cases successfully settled.
    • Represented an innovator client in Hatch-Waxman litigation regarding prescription insomnia medication with no NCE exclusivity. Multiple cases successfully settled during expert discovery.
    • Represented an innovator client in Hatch-Waxman litigation regarding prescription diabetes medication, obtaining preliminary injunction against an at-risk launch from the district court. Case successfully settled.
    • Represented an innovator client in Hatch-Waxman litigation regarding prescription steroid medication. Case successfully settled.
    • Represented a defendant biotechnology company in a declaratory judgment action regarding multiple client patents. Case successfully settled.
    • Performed numerous portfolio reviews of Orange and Green book-listed patents.


    • Rutgers University School of Law, J.D., 1991
    • University of Pennsylvania, B.A.


    • New York, 2010
    • District of Columbia, 1993
    • New Jersey, 1991


    • U.S. Supreme Court
    • U.S. Court of Appeals for the Federal Circuit
    • U.S. Patent and Trademark Office

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    • Author, “Blocking Patent Doctrine May Now Apply To All Technologies,” Law360, December 6, 2019.
    • Author, “Federal Circuit Offers Obviousness-type Double Patenting Cure,” Law360, November 5, 2019.
    • Author, “The Law on Damages in Generic Drug Launches Remains Vague,” New York Law Journal, January 6, 2014.
    • Author, “The FDA Exemption & Research Tools: The Federal Circuit Gets It Wrong,” Intellectual Property Today, June, 2009.

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