Leon Kotlyar joined Ropes & Gray in 2015 as an associate in the firm’s litigation department. His practice spans a wide array of matters, including national multidistrict litigation, complex commercial disputes, labor and employment cases, data security breaches, securities litigation, and government and internal investigations. He litigates in federal and state court, at the trial and appellate levels.

During law school, Leon served as an articles editor of the California Law Review and was a teaching assistant of a legal writing class. He also interned for the Honorable John T. Noonan, Jr. of the United States Court of Appeals for the Ninth Circuit. Prior to law school, Leon taught high school math as a Philadelphia Teaching Fellow and before that worked in the communications department at Google.


  • Represents leading biomedical research institution in employment discrimination cases in D. Mass. and Maryland state court.
  • Represents plaintiff homeowners in an S.D.N.Y class action challenging the constitutionality of New York City’s property seizures.
  • Represents global biopharmaceutical manufacturer in nationwide litigation concerning its prescription opioid medications.
  • Represented company that operates global restaurant and entertainment brands in S.D. Tex. litigation against the company’s former payment card processor relating to a data security incident.
  • Represented one of the largest independent broker-dealers and its senior executives in a class action alleging securities fraud in S.D. Cal.
  • Represented consulting firm seeking to enjoin competitor’s enforcement of restrictive employment agreements.
  • Represented LabMD in its successful petition to the Eleventh Circuit resulting in the first-ever court decision overturning an FTC cybersecurity action.
  • Represented largest creditor in high-profile bankruptcy litigation in Delaware regarding bidder’s rights to a $275 million termination fee for failed takeover of the largest electric utility in Texas.
  • Represented Olshan Properties in a dispute with The Limited concerning a right of first offer for a hotel project that would compete with a hotel jointly owned and developed by the parties.
  • Represented various financial institutions, including large global banks and investment management firms, in responding to SEC investigations.
  • Represented biopharmaceutical company in multi-year joint DOJ and SEC investigation into alleged off-label promotion.
  • Conducted internal investigation for global pharmaceutical company in connection with alleged FCPA violations in Russia.
  • Assisted trial team in defending the son of former New York State Majority Leader Dean Skelos against public corruption charges in S.D.N.Y.
  • Secured grant of asylum for refugee from El Salvador who fled the country after receiving death threats for starting a local political opposition group.

Areas of Practice