Kate Cassidy

Kate E. Cassidy

152 W 57th Street, 19th Floor, New York, NY 10019
tel: (332) 244-7015 || cell: (917) 703-6809


Kate Cassidy is an experienced trial lawyer representing clients in complex technology and intellectual property disputes. Considered by clients to be an “extraordinary attorney”, she excels as a creative litigation strategist. Kate focuses on trial themes and case economics from the outset of every engagement to ensure the client has a candid assessment of strengths and weaknesses of their claim.  She then brings her determination and faithful dedication to winning at trial to every case so that the client is best positioned to achieve a win, either through trial or a favorable settlement.

She has successfully handled a variety of litigations and arbitrations on behalf of startups through large companies (including Fortune 500) from varied industries including software, pharmaceuticals, medical devices, biotech, materials and textiles, telecom, internet infrastructure, financial services, and retail and consumer goods.

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.

Notable Representations

Patent Litigation

Trial counsel to YKK in a patent infringement and false advertising case in the Southern District of New York. Devised successful strategy to reduce the multi-million dollar false advertising claim, and after a bifurcated trial, the case settled on favorable terms.

Soverain Software LLC in 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.

Represented Symantec Corporation in several patent cases in the Northern District of California and District of Delaware regarding backup and recovery software. Cases settled favorably after filing summary judgment motions.

Defended 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.

Represented various brand pharmaceutical companies against generic companies in Hatch Waxman ANDA litigation including against Teva, Amneal Pharmaceuticals and others in separate unrelated matters, reaching successful settlements or summary judgment.

Represented 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.

Trademark Litigation

Represented PGA of America in confidential arbitration successfully resolving a trademark and breach of contract dispute.

Defended Legal & General (insurance/financial services) in a breach of contract and trademark infringement matter in District of Connecticut against The Travelers Companies successfully resolving the case, involving use of their respective logos on favorable terms.

Represented Deckers Outdoor Corporation in various trademark matters in the Central District of California, regarding protection of the Deckers famous “Uggs” trademark and the trade dress of its footwear designs. Resolved the cases on favorable terms.

Commercial Litigation

Defended Mirae Asset Management in a Delaware Court of Chancery litigation obtaining decision to terminate $6 billion transaction for 15 luxury hotels.

Represented 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.

Took over defense of Bell & Howell in a consumer class action in Southern District of New York on the eve of trial after the Court denied summary judgement. Chief strategist for trial preparation and pretrial motions that put Plaintiffs’ damages claims at risk and set up a favorable settlement.

Defended Wellquest International in a breach of contract litigation in California Supreme Court involving consumer beauty products. Obtained summary judgment and successfully defended victory on appeal.

Represented aTelo in an international arbitration regarding breach of contract dispute with a Polish telecom company. Arbitration award granted all requested relief.


Kate’s cross-examination of key trial witness before EDTX jury .

Kate’s successful pre-trial oral argument transcripts opposing Defendants’ motion to amend invalidity contentions , asking the Court to strike Plaintiff’s key infringement theories , and discovery motion .


Michael Carlinsky, Global Co-Managing Partner & Global Head Complex Litigation: Kate and I worked together for years, and I can attest to her many strengths as a litigator.


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


Bar Admissions
New York

Court Admissions
U.S. District Court for the Southern District of New York
U.S. District Court for the Eastern District of New York
U.S. Court of Appeals for the Federal Circuit
U.S. Court of Appeals for the Second Circuit

Prior Affiliations

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