Katharine O’Connor focuses her practice on complex antitrust litigation, government investigations, defending mergers and acquisitions before antitrust enforcement agencies, and counseling clients on antitrust compliance issues. She has experience representing clients in a wide array of industries, including health care, manufacturing, food and finance
Katharine is a member of the firm’s antitrust and competition practice, which has been designated a “Global Elite” practice, one of the top 25 in the world, by Global Competition Review each year since 2013. She has been recognized by Legal 500 US and Super Lawyers as excelling in the field of antitrust.
Katharine has tried cases before juries, judges and arbitration panels, presented evidentiary hearings in federal and administrative courts, and argued before the US Court of Appeals for the Seventh Circuit, federal district courts and state courts.
While in law school, Katharine was the managing articles editor of the University of Illinois Law Review and a legal extern to Magistrate Judge David G. Bernthal of the US District Court for the Central District of Illinois
Defeated certification on impact and damages of proposed direct purchaser class in In re Steel Antitrust Litigation, which was the largest class action in the country when it was filed, and in which plaintiffs claimed damages in excess of a $17 billion for alleged price fixing and coordinated capacity restrictions
Achieved dismissal with prejudice on behalf of joint defense group, which was affirmed by the Seventh Circuit, of all indirect purchaser claims in In re Steel Antitrust Litigation
Achieved dismissal with prejudice on behalf of a Group Purchasing Organization (GPO) in a case alleging a vertical conspiracy under the antitrust laws between medical device manufacturer, distributors, and GPOs
Negotiated highly favorable settlement, after the trial court dismissed the case all counts, for Silver Cross Hospital in a class action lawsuit alleging unfair competition and consumer fraud
Obtained early and favorable settlement for hospital system in a lawsuit brought by a physician alleging monopolization, attempted monopolization, and exclusive dealing claims
Represented several third-parties in litigation brought by the Federal Trade Commission to block the merger of two competing health systems in northern Illinois
Defending Southern Illinois Healthcare, the largest health system in southern Illinois, in antitrust litigation brought by a competing ambulatory surgery center based on allegedly exclusive contracts
Secured antitrust clearance and avoided second request for merger of two large private label food manufacturers
Counseled several health care providers and other health care industry participants on antitrust issues arising out of affiliations and mergers and acquisitions across the country
Served as a member of a trial team that secured a complete defense verdict for Celanese, a leading producer of chemicals, fibers and engineered plastics, in case seeking approximately $4 billion in damages
Served as a member of a trial team that obtained a favorable settlement for a leading alcohol beverage supply company
Second-chaired a trial in a federal district court, representing a construction and manufacturing equipment distributor
Argued before the US Court of Appeals for the Seventh Circuit in a pro bono case, obtaining a reversal and remand for a client for violations of the client’s Miranda and Sixth Amendment rights (United States v. Wysinger, 683 F.3d 784 (7th Cir. 2012))
US District Court for the Northern District of Illinois
US District Court for the Southern District of Illinois
US District Court for the Western District of Michigan
US District Court for the Eastern District of Wisconsin
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