James R. Sigel

Partner | San Francisco

jsigel@mofo.com | (415) 268-6948

(415) 268-6948

James Sigel is a partner in Morrison & Foerster’s Appellate and Supreme Court practice. James briefs and argues complex appeals for clients nationwide. He has particular experience in the U.S. Court of Appeals for the Ninth Circuit and in the California state appellate courts, having argued 13 times in those courts.

James has handled appeals in many areas of law, including class actions, securities, false advertising, antitrust, and environmental regulation. He has briefed dozens of appeals in federal and state appellate courts throughout the country, including the U.S. Supreme Court, the U.S. Courts of Appeals for the First, Second, Fourth, Seventh, Ninth, and D.C. Circuits, as well as the New York and California state courts.

James is an experienced appellate advocate on the west coast, where he clerked on both the Ninth Circuit and the California Supreme Court. His successful oral argument in the Ninth Circuit resulted in a victory for his client UPS in False Claims Act litigation that had been ongoing for more than a decade. Among James’s other victories, he has defeated multiple class actions against a leading consumer electronics corporation, secured a win for a major beverage company defending against a monopolization claim, and prevailed in another antitrust claim involving an alleged conspiracy in the shipment industry.

A former law clerk on the U.S. Supreme Court, James has authored more than a dozen briefs in that Court on important constitutional and statutory interpretation issues. James led the briefing on two cases during the Supreme Court’s 2019 term: Thole v. U.S. Bank and Atlantic Richfield Co. v. Christian. Law360 named Thole as among the “biggest ERISA rulings” and Christian as one of the “biggest environmental law decisions” of 2020.

James maintains an active pro bono practice, having briefed and argued appeals involving constitutional, criminal, and immigration issues. He is also the lead editor of Morrison & Foerster’s Left Coast Appeals blog, which keeps tabs on the Ninth Circuit and its decisions.

Before joining Morrison and Foerster, James clerked on the U.S. Supreme Court for Justice Sonia Sotomayor. Before the Supreme Court, James clerked for Judge David Tatel on the D.C. Circuit, Justice Goodwin Liu on the California Supreme Court, and Judge Stephen Reinhardt on the Ninth Circuit.

James graduated magna cum laude from Harvard Law School, where he was a Notes Editor of The Harvard Law Review. He received his undergraduate degree from Harvard College magna cum laude, with a Bachelor of Arts in Government and Economics.

Representative Appellate Arguments

  • U.S. ex rel. DeFatta v. UPS (15:22)
    (9th Cir.) Successfully argued and briefed appeal securing dismissal of False Claims Act lawsuit.
  • Kearney v. Foley & Lardner LLP (11:22)
    (9th Cir.) Argued and won victory in appeal ending long-running dispute over school district’s taking of private property.
  • John Russo Industrial Sheetmetal, Inc. v. City of Los Angeles Department of Airports
    (California, First District Court of Appeal) Argued and won judgment for airport authority in case challenging purported debarment of contractor.
  • Doe v. Kelly (0:00)
    (9th Cir.) Argued and secured affirmance of preliminary injunction requiring the federal government to improve conditions of confinement in Border Patrol detention centers.

Additional Representative Matters

  • Thole v. U. S. Bank, N. A.
    (U.S. S. Ct.) Prevailed in case concerning Article III standing limitations on ERISA lawsuits.
  • Atlantic Richfield Co. v. Christian
    (U.S. S. Ct.) Defeated claim that CERCLA precluded state-law tort claims for property damage.
  • AFMS v. United Parcel Service and FedEx
    (9th Cir.) Prevailed in significant antitrust case, defeating claims against client UPS.
  • Lower Elwha Klallam Indian Tribe v. Lummi Nation
    (9th Cir.) Won reversal for the Lummi Nation, reclaiming its historic treaty rights.
  • Bank v. Uber Technologies, Inc.
    (2d Cir.) Obtained dismissal of a Telephone Consumer Protection Act suit on the ground that the call was political speech.
  • Flores v. UPS & Pocino Foods v. UPS (Consolidated)
    (9th Cir.) Secured judgment for UPS on two putative RICO and breach-of-contract class actions about its Next Day Air services.
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