William Perdue focuses his practice on appellate and trial cases that raise novel or complex questions of law. He has represented clients in cases presenting a wide range of issues, including the First Amendment, administrative law, insurance, intellectual property, environmental regulation, antitrust, and foreign sovereign immunity.

Mr. Perdue has recently represented parties in appellate and trial proceedings before the US Supreme Court, the US Courts of Appeals for the Second, Fourth, Fifth, Ninth, Federal, and DC Circuits, federal district courts in New York, Maryland, and California, and state courts in New York, North Carolina, and Delaware.

Prior to joining the firm, Mr. Perdue served as a law clerk to the Honorable Anthony M. Kennedy of the United States Supreme Court, the Honorable Robert A. Katzmann of the United States Court of Appeals for the Second Circuit, and the Honorable Jed S. Rakoff of the United States District Court for the Southern District of New York.

Mr. Perdue is a graduate of Yale Law School, where he was awarded the Benjamin N. Cardozo Prize for best moot court brief and the Thomas I. Emerson Prize for best paper on a subject related to legislation, and served as Co-Editor-in-Chief of the Yale Journal of International Law.


  • Insurance company in two successful appeals to the Delaware Supreme Court regarding the scope of coverage provided to public companies under directors-and-officers insurance policies. In re Solera Insurance Coverage Appeals, 240 A.3d 1121 (Del. 2020); In re Verizon Insurance Coverage Appeals, 222 A.3d 566 (Del. 2019).
  • Restaurant brand in successful appeal of consumer class action raising novel issues of personal jurisdiction and false advertising law. Chen v. Dunkin’ Brands Inc., 914 F.3d 492 (2d Cir. 2020).
  • Pharmaceutical manufacturer in successful appeal to the Delaware Supreme Court in major breach-of-contract dispute regarding the implied covenant of good faith and fair dealing. Glaxo Grp. Ltd v. DRIT LP, 248 A.3d 911 (Del. 2021).
  • Pharmaceutical manufacturers in successful challenge to preliminarily enjoin CMS interim final rule overhauling drug pricing under Medicare Part B. Ass’n of Cmty. Cancer Centers v. Azar, 2020 WL 7640818 (D. Md. Dec. 23, 2020).
  • Property developer in successful appeal to the DC Court of Appeals regarding application of historic preservation law to major redevelopment project. DC Preservation League v. Mayor’s Agent for Historic Preservation, 236 A.3d 373 (DC 2020).
  • Ethanol producer in appeals challenging denial of registration application by EPA under the Renewable Fuel Standard Program. POET Biorefining - Hudson, LLC v. EPA, 971 F.3d 802 (8th Cir. 2020); POET Biorefining, LLC v. EPA, 970 F.3d 392, 397 (DC Cir. 2020).
  • Challengers in successful voting rights litigation to redraw North Carolina’s state legislative and congressional maps under state law. Common Cause v. Lewis, 2019 WL 4569584 (NC Super. Sep. 03, 2019); Harper v. Lewis, No. 19-cvs-012667 (NC Super. Ct.).
  • Oil company in successful appeal arguing that professional athlete was not harmed by oil spill. BP Expl. & Prod., Inc. v. Claimant Id 100281817, 919 F.3d 284, 286 (5th Cir. 2019).
  • Pharmaceutical manufacturer in successful appeal arguing that plaintiff’s tort claims for failure to warn were preempted by the Federal Food, Drug & Cosmetic Act. Dolin v. GlaxoSmithKline LLC, 901 F.3d 803, 805 (7th Cir. 2018).
  • Religious hospital system in appeal to preserve a pension plan's eligibility for the "church plan" exemption to the Employee Retirement Income Security Act (ERISA). Rollins v. Dignity Health, 830 F.3d 900 (9th Cir. 2016).
  • Pharmaceutical manufacturer in appeal in antitrust litigation brought by the Attorney General of New York. New York ex rel. Schneiderman v. Actavis PLC, 787 F.3d 638 (2d Cir. 2015).
  • Banking executive in successful appeal from administrative actions by the Office of the Comptroller of the Currency and the Federal Reserve Board. DeNaples v. Office of the Comptroller of the Currency, 706 F.3d 481 (DC Cir. 2013).
  • Pharmaceutical manufacturers in appeal challenging price caps imposed by the Department of Defense. Coalition for Common Sense in Government Procurement v. United States, 707 F.3d 311 (DC Cir. 2013).
  • Pharmaceutical manufacturer in appeal from grand jury investigation regarding off-label marketing. In re: Grand Jury Matter, Case No. 11-2679 (3d Cir.).



Best Lawyers
"Ones to Watch"—Appellate Practice (2023)
The Legal 500 US
Appellate: Courts of Appeals / Appellate: Supreme Courts (States and Federal) (2021–2022)


  • JD, Yale Law School, 2011
  • BA, Yale College, 2007, summa cum laude, Phi Beta Kappa
  • District of Columbia
  • New York
  • US Court of Appeals for the Second Circuit
  • US Court of Appeals for the Fifth Circuit
  • US Court of Appeals for the Sixth Circuit
  • US Court of Appeals for the Seventh Circuit
  • US Court of Appeals for the Ninth Circuit
  • US Court of Appeals for the Eleventh Circuit
  • Supreme Court of the United States, The Honorable Anthony M. Kennedy
  • US Court of Appeals for the Second Circuit, The Honorable Robert A. Katzmann
  • US District Court, Southern District of New York, The Honorable Jed S. Rakoff

Email Disclaimer