Danielle R.Leneck


Los Angeles +

Danielle Leneck's practice focuses on antitrust litigation in state and federal courts. She has extensive experience in factual investigation, offensive and defensive discovery including depositions and witness preparation, motions practice, and trial. The clients she has represented have operated in a wide variety of business sectors and industries, including oil and gasoline refining and marketing, health care, aviation, transportation, and telecommunications.

Danielle's recent matters include a full and unanimous defense verdict for Sutter Health in a month-long antitrust class action trial alleging Sutter restrained competition by forcing insurers to include certain hospitals in their provider networks and preventing them from steering patients to other hospitals; obtaining summary judgment for Marathon Petroleum in an antitrust class action in which plaintiffs alleged that Marathon and other major gas refiners conspired to reduce supply and inflate gas prices and sought $72 billion in treble damages; defending a Class I railroad in two antitrust multidistrict litigations in which hundreds of plaintiffs allege a price-fixing conspiracy through the application of fuel surcharges; and defending a Japanese capacitor manufacturer against an add-on price-fixing class action litigation following a Department of Justice (DOJ) guilty plea.

Danielle is actively involved in her local community. She maintains a devoted pro bono practice that focuses on representing clients seeking political asylum. In addition, she serves on the Diversity, Inclusion & Advancement Committee in the Los Angeles Office and represents Jones Day as its sitting member on both the Young Leaders Division of the Association of Business Trial Lawyers and the New Leadership Council and Executive Committee of Bet Tzedek.


  • Tesoro wins summary judgment dismissing two consolidated antitrust class actionsAs lead counsel of Tesoro Refining and Marketing Company, a subsidiary of Marathon Petroleum Corporation, Jones Day won summary judgment in two consolidated antitrust class actions in which gasoline stations and consumers sought a combined $72 billion in treble damages.
  • Sutter Health wins complete defense verdict in landmark antitrust class actionJones Day won a complete defense jury verdict for Sutter Health in a landmark antitrust class action seeking $1.2 billion in treble damages.