Cali Arat


Cali Arat (née Cope-Kasten) is a Partner at Wilkinson Stekloff. Since joining the firm at its founding in 2016, she has served as a key member of more than half of the firm’s trial teams, including most recently leading the representation of Monsanto in the first hybrid trial involving claims that exposure to PCBs and Roundup-branded products, both manufactured by Monsanto, cause Non-Hodgkin Lymphoma.

Cali has helped to develop and execute successful trial strategies for corporate clients across a diverse set of industries, from pharmaceuticals to sports to social media. Her experience includes seven jury trials, three of which were federal multi-district litigation bellwether cases, two of which were bench trials, and two of which were in-person jury trials during the COVID-19 pandemic. She has argued numerous motions in state and federal courts at the trial and appellate level.

Cali has also helped obtain successful results for clients prior to trial. Her work has included representing former State Department officials in a nationally publicized series of cases brought under the Freedom of Information Act, and she has briefed every stage of litigation, including securing a full grant of summary judgment for Georgia-Pacific LLC in a multibillion-dollar consumer class action.

In addition to her impressive legal skills, Cali is dedicated to mentoring and is viewed by associates as a “go-to” leader for any issue — whether personal or professional — based on her trustworthiness and strategic judgment. Cali also currently serves as the co-chair of Wilkinson Stekloff’s DEI Committee.

Cali’s work has earned her wide recognition. She has been identified as a “Rising Star of the Courtroom” by Business Insider and selected for Lawdragon’s “500 X – The Next Generation.” She is recognized as a “Litigation Star” and named to Benchmark’s “Top 250 Women in Litigation” and top “40 & Under Hotlist.” The National Law Journal honored Cali as a “Rising Star,” and she was featured in’s “How I Made Partner” series.

Before joining Wilkinson Stekloff, Cali clerked for Chief Judge John R. Tunheim, United States District Court for the District of Minnesota. She earned her B.A., summa cum laude, from Macalester College and her J.D., magna cum laude, from the University of Michigan.


  • Undergraduate: Macalester College, B.A., summa cum laude
  • Law: University of Michigan, J.D., magna cum laude; Order of the Coif; Managing Board, University of Michigan Journal of Law Reform


  • Judge John R. Tunheim, United States District Court for the District of Minnesota

Notable Matters

  • Lead trial counsel in Frank v. Monsanto, a trial involving claims that the herbicide Roundup and PCB exposure together cause Non-Hodgkin Lymphoma. Cali argued several Daubert motions, conducted voir dire, and handled key direct- and cross-examinations.
  • Served as trial counsel in Clark v. Monsanto, a trial involving claims that Roundup causes Non-Hodgkin Lymphoma. Cali argued the general-causation Daubert motion and handled several witnesses. Clark was the fourth case in this mass tort to go to trial, with the three previous trials resulting in verdicts against Monsanto ranging from $81 million to over $2 billion. After a single day of deliberation, the jury delivered the first-ever verdict for Monsanto in the Roundup mass tort litigation.
  • Member of the trial team for Monsanto in Hardeman v. Monsanto, the first federal-court trial over allegations that Roundup causes Non-Hodgkin Lymphoma. The jury returned a verdict for the plaintiff. Cali has assisted with post-trial briefing, as well as ongoing witness preparation and strategy in the larger MDL.
  • Helped brief summary judgment for Georgia-Pacific in Kleen Products LLC et al. v. Packaging Corporation of America et al., a multibillion-dollar class action in Chicago federal court alleging Sherman Act violations by the largest manufacturers in the containerboard industry. The court granted summary judgment for Georgia-Pacific one day after it preliminarily approved a settlement in which the company’s codefendants agreed to pay over $350 million.
  • Member of trial team for the NCAA in lawsuits brought by current and former student-athletes challenging, under the Sherman Act, NCAA rules limiting the level of athletics-based financial aid and benefits that student-athletes may receive. The Court’s opinion reaffirmed the procompetitive value of the NCAA’s rules limiting pay for student-athletes while enjoining certain limitations on benefits that student-athletes may receive. Cali is now one of the team leads for the NCAA in a new, related class action involving student-athlete name, image, and likeness rights, seeking what could be billions of dollars in damages.
  • Member of trial teams for Bayer in the first two federal multi-district litigation bellwether trials in Louisiana involving the blood-thinner Xarelto, and in the second state-court bellwether trial in the Philadelphia Court of Common Pleas. Obtained complete defense verdicts in all three trials.
  • Member of trial team on behalf of Facebook, Oculus VR, and individual defendants in ZeniMax Media et al. v. Oculus VR et al., a federal jury trial in the Northern District of Texas. Plaintiffs sought $6 billion in damages based on allegations that the defendants improperly used its trade secrets and other intellectual property in designing the Oculus Rift virtual reality headset. Obtained a full defense verdict for Facebook and a partial defense verdict for the remaining defendants, including the jury’s rejection of plaintiffs’ lead claim of trade secret misappropriation. Cali assisted with Wilkinson Stekloff’s post-trial briefing, which persuaded the court to sanction plaintiffs for withholding evidence and prevented them from recovering $40 million in attorneys’ fees.
  • Won an appeal at the D.C. Court of Appeals affirming her earlier trial win in Brian Macklin v. Janai Johnson, a complex and contentious divorce and child custody case. The appeal followed a five-day trial in D.C. Superior Court at which Cali and the Wilkinson Stekloff team, representing their client pro bono, won primary physical custody of the parties’ five children, tie-breaking authority in legal custody, and a 40% interest in the parties’ marital home. The Court’s precedential 32-page opinion affirmed Ms. Johnson’s victory on all issues and gives hope to other women in Ms. Johnson’s position.


  • It’s Time to Start Showing a Little Restraint: In Search of a Compromise on Federal Seclusion and Restraint Legislation, 47 U. MICH. J.L. REFORM 217 (2013).
  • Bidding (Fair)well to Due Process: The Need for a Fairer Final Stage in Special Education Dispute Resolution, 42 J.L. & EDUC. 501 (2013).
  • Cali Cope-Kasten & Patrick Schmidt, Book Review, 17 L. & POL. BOOK REV. 158 (2009) (reviewing DAVID KAIRYS, PHILADELPHIA FREEDOM: MEMOIR OF A CIVIL RIGHTS LAWYER (2008)).

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