Zachary Clark is an Associate at Keller Postman LLC. He is a skilled litigator who has successfully represented clients in high-stakes matters in trial and appellate courts and arbitral forums across the country.

Zach’s current practice focuses on mass torts, including product liability litigation against infant formula manufacturers in suits alleging that their infant formula products cause premature infants to develop necrotizing enterocolitis, a serious gastrointestinal condition.

Before joining Keller Postman, Zach was an Associate at Quinn Emanuel Urquhart & Sullivan, LLP. He represented both plaintiffs and defendants in diverse cases across a wide range of subject matters, including mass torts, class actions, securities fraud, patents, and administrative litigation involving state and federal government entities.

Zach has helped clients obtain favorable outcomes in numerous cases. For example, he helped a plaintiff real estate developer obtain a favorable settlement in a lawsuit against the City of Indianapolis related to the City’s efforts to seize a large development property. Zach was also part of a team that defended a property preservation services company against trespass and unfair practices claims, resulting in the Ninth Circuit’s affirmance of partial summary judgment and a later district court order granting summary judgment on the remaining claims.

Zach also successfully represented Nokia in multiple patent appeals before the Federal Circuit, procuring affirmances of district court orders granting judgment to Nokia based on patent invalidity and noninfringement.

Zach served as a law clerk for Judge Martha M. Pacold on the Northern District of Illinois and Judge Julie E. Carnes on the Eleventh Circuit Court of Appeals. He graduated with high honors from the University of Chicago Law School, where he was a member of the Order of the Coif and received the Thomas R. Mulroy Prize for Excellence in Appellate Advocacy and Oral Argument in the Hinton Moot Court competition. Zach was also a member of the University of Chicago Law Review and Executive Editor of the University of Chicago Legal Forum.

Zach graduated with highest distinction from the University of Kansas with a degree in political science and international studies.

Zach is licensed to practice law in the District of Columbia and Illinois only.


"I’m proud to be at Keller Postman because we’re able to provide the highest quality legal representation to everyday people—folks that, unlike big corporations, may not be able to afford an attorney or otherwise have their day in court."

Zachary Clark

Education & Clerkships

  • J.D., University of Chicago Law School
  • B.A., University of Kansas
  • Clerkship: U.S. District Court for the Northern District of Illinois
  • Clerkship: U.S. Court of Appeals for the Eleventh Circuit

Previous Affiliations

  • Quinn Emanuel Urquhart & Sullivan LLP
  • Harris, Wiltshire & Grannis LLP