Karim Z. Oussayef

Specialty / focus areas. Karim Z. Oussayef is a partner at Desmarais LLP in New York, an intellectual-property litigation boutique, where he has practiced since 2011 (associate, then partner); he previously was an associate in Ropes & Gray LLP's IP group (2008–2010). His practice is high-stakes patent and technology litigation spanning software, e-commerce, machine-learning/AI, wireless (Bluetooth), and wearable-device technologies, with trial and Federal Circuit appellate work. He holds a B.S. in computer science (University of Rochester) and a J.D. (Boston University, magna cum laude), and is admitted in New York (2009) and Massachusetts (2008). His firm bio and Law360 profile corroborate these credentials.

Side preference. In the tracked appearances he is uniformly defendant-side (4 of 4), including lead counsel for Zesty.AI, Inc. in Aon Re, Inc. v. Zesty.AI, Inc. (D. Del.) and defense work for operating companies such as Fitbit and IBM in IPRs. His broader record, however, includes patentee-side work for IBM (the IBM v. Groupon verdict and the IBM v. Priceline appeals), so he is capable on both sides but the tracked docket skews toward defending operating companies against infringement and § 101 challenges.

Notable cases / outcomes. In Aon Re v. Zesty.AI (No. 1:25-cv-00201, D. Del.), he represents Zesty.AI against Aon's four patents on machine-learning classifiers that analyze aerial property imagery for insurance-risk assessment; in July 2025 the court denied Zesty's Alice-based motion to dismiss (Law360, Vitallaw). In IBM v. Groupon, he helped secure an $82.5 million jury verdict for IBM on e-commerce patents (later settled), earning a 2019 Law360 Rising Star recognition. In Philips North America v. Fitbit (D. Mass.), he was on the Fitbit team that won summary judgment invalidating Philips's fitness-tracker patent under § 101. He also argued and won a Federal Circuit reversal of two PTAB decisions invalidating an IBM authentication patent in the Priceline dispute.

PTAB / IPR experience. Oussayef appears regularly before the PTAB, principally representing patent owners (e.g., IBM) in IPRs — including a proceeding where he and a colleague cancelled all claims of a competitor's patent (per IAM Patent 1000) — plus the successful Federal Circuit appeal overturning adverse IPR decisions. His firm bio confirms he "appears regularly before the Federal Circuit." In the related Zesty.ai v. Aon Re IPR (IPR2025-01360), institution was denied on discretionary grounds in November 2025, though counsel listings there identify Gardella and Block rather than Oussayef.