Kate Cassidy

Tel: 332-206‐0206
Fax: 213-612-3773


  • Georgetown University Law Center (L.L.M., International Legal Studies, with distinction, 2005)
  • University of Adelaide Law School (L.L.B., with honors, 2003)
  • University of Adelaide School of Molecular and Life Sciences (B.S., Biochemistry, Microbiology, Immunology, 2001)


  • Quinn Emanuel Urquhart & Sullivan, LLP
  • Nixon Peabody LLP
  • Willkie Farr & Gallagher LLP


Kate E. Cassidy is an experienced trial lawyer whose practice focuses on high-stakes commercial litigation and intellectual property disputes, with an emphasis on patent litigation.  She has represented companies ranging from startups through Fortune 100 companies in a variety of industries, including:

  • software: antivirus and backup and recovery products
  • pharmaceuticals
  • medical devices
  • polymers
  • telecommunications
  • internet infrastructure
  • financial services
  • retail and consumer goods

Kate has litigated in jurisdictions throughout the country, including courts in Delaware, California, Texas, Minnesota, New Jersey and New York and in international and domestic arbitration.

Kate maintains an active pro bono practice, including a longstanding representation of Advocates for Children, which helps New York children with special needs obtain a free and appropriate education. Before joining the firm, Kate practiced in the New York offices of Quinn Emanuel Urquhart & Sullivan, LLP and Nixon Peabody LLP and as a foreign attorney in the Washington DC office of Willkie Farr & Gallagher LLP.

Kate is admitted to practice in New York.

Representative Experience


  • Mirae Asset Management in a Delaware Court of Chancery litigation obtaining decision to terminate a $6 billion transaction for 15 luxury hotels.
  • PGA of America in a confidential arbitration successfully resolving a breach of contract dispute.
  • ResCap Liquidating Trust in suits against dozens of loan originators in the District of Minnesota for indemnity and breaches of contract arising from the sale of defective mortgage loans, achieving settlements of $1.2 billion and a multi-million dollar jury verdict.
  • Legal & General in a breach of contract and trademark infringement dispute in the District of Connecticut against The Travelers Companies successfully resolving the case on favorable terms.
  • Bell & Howell in a consumer class action in Southern District of New York, successfully resolving the case on favorable terms.
  • Wellquest International in a breach of contract litigation in California Supreme Cout involving consumer beauty products.  Obtained summary judgment and successfully defended the victory on appeal.
  • Symantec Corporation in several cases in the Northern District of California and District of Delaware with respect to patents covering backup and recovery software.  Cases settled favorably after filing summary judgment motions.
  • Symantec Corporation in patent litigation in the Northern District of California, regarding anti-virus software.  Case settled favorably after winning a key motion that gutted Plaintiff’s damages case.
  • Stiefel Laboratories/Connetics Corp. in Hatch Waxman patent litigation in the District of New Jersey regarding Connetics’ branded product OLUX® Foam.  Case settled favorably.
  • EKR Therapeutics in Hatch Waxman patent litigation in the District of New Jersey regarding EKR’s branded product CARDENE® I.V.  Prevailed on summary judgment.
  • Forest Laboratories against Teva and Amneal Pharmaceuticals in Hatch-Waxman litigation in the District of Delaware.  Case settled favorably.
  • Soverain Software LLC in a patent infringement case in the Eastern District of Texas involving e-commerce technology against a number of defendants including J.C Penney, Victoria’s Secret, Avon and other online retailers.  Obtained jury verdict of infringement, validity, and millions in damages.
  • INVISTA, a subsidiary of Koch Industries, in a breach of contract and patent infringement litigation in the Southern District of New York.  Case settled favorably after filing an early motion for summary judgment.
  • Deckers Outdoor Corporation in various trademark matters in the Central District of California, regarding protection of Deckers’ famous “Uggs” trademark and the trade dress of its footwear designs.  Resolved the case on favorable terms.
  • aTelo in an international arbitration regarding a breach of contract dispute with a Polish telecom company.  Arbitration award granted all requested relief.
  • Foreign governments and companies in anti-dumping and counter-vailing duty investigations involving products from Vietnam, Thailand, Japan, Canada, and China.  Obtained favorable tariff rates.