University of Illinois College of Law, J.D.
  • summa cum laude; Order of the Coif
  • University of Illinois Law Review
University of Illinois, B.A.

Prior Employment

  • Winston & Strawn LLP, Capital Partner, 1989-2015

Bar Admissions

Professional Affiliations

Leadership Greater Chicago, Fellow

The Innocence Project

  • Lawyer's Advisory Committee
  • Development Committee
  • Annual Gala Committee
News & Resources


Mr. Koropp is an experienced trial attorney who has represented clients in some of their most complex and significant accounting/auditor liability, commercial, class action, antitrust, real estate and patent litigation matters. With more than 26 years of trial experience, he has represented clients as a first-chair trial attorney in jury and bench trials, arbitrations, and contested evidentiary hearings ranging from bet-the-company cases for Fortune 100 clients to more modest disputes involving privately held businesses and wealthy individuals.

  • Engages in contract dispute litigation representing:
    • publicly and privately held companies in disputes involving mergers, acquisitions, indemnity agreements and supply contracts
    • privately held smaller firms involving commercial leases, real estate development agreements and brokerage contracts
  • Defends law firms and individuals in attorney malpractice actions as well as accounting and auditing liability litigation
  • Represents clients, including major financial institutions, telecommunication companies, home healthcare providers, medical device manufacturers in state and nationwide class action litigation matters
  • Represents clients in securities litigation matters involving mergers, acquisitions, initial public offerings, asset purchase transactions and complex financing transactions
  • Defends clients in a variety of industries against claims of patent tying, exclusive dealing and illegal price fixing under the Sherman and Clayton Acts
  • Litigates patent cases involving a wide array of products and industries, including pharmaceutical, computer software, digital mapping, navigation and automotive traffic monitoring
  • Represents Fortune 100 and small start-up companies as well as wealthy individuals with trademark and copyright infringement, and false advertising cases involving a diverse array of products, including sodas, diet plans, batteries and internet search services
  • Defends major print and television news organizations, as well as local and regional newspapers, in libel litigation
  • Leads teams of attorneys in conducting internal investigations into potential corporate wrongdoing both domestically and overseas
  • Counsels business executives, board members, general counsels and small business owners on legal aspects of their business strategies, means of resolving disputes while reducing legal expenditures, and methods for assessing and reducing risk while meeting business objectives


  • Represented a Big Four accounting firm in a large, highly complex audit malpractice case arising out of a financial restatement spanning several years
  • Represented a Big Four accounting firm in a multi-billion arbitration arising out of a massive financial restatement that involved substantial wrongdoing by the company’s top executives
  • Represented a major consumer products manufacturer in an antitrust case alleging a variety of anticompetitive acts, including patent tying and exclusive dealing
  • Represented major Southern California developer in multi-week arbitration arising out of failed development project
  • Defended one of the largest financial institutions in the country in a breach of contract and breach of fiduciary duty arbitration
  • Represented one of the largest home improvement companies in an indemnity trial arising out of a sale of one of the company’s major divisions
  • Represented an overseas pharmaceutical company in a patent infringement lawsuit brought to block approval of my client’s application with the FDA seeking permission to market a generic version of a highly successful pain medicine
  • Represented a small, privately held manufacturer in a contract case arising out of the sale of the business to a much larger company
  • Represented a local real estate developer in a trial arising out of dispute over a broker’s commission
  • Represented the manager of an internationally renowned singer/songwriter in a trial before the California Labor Commission arising out of my client’s alleged violations of the California Talent Agencies Act
  • Represented a former police officer imprisoned for more than nine years for a kidnapping and rape he did not commit and convinced a federal court to overturn his conviction and grant him a new trial based on the incompetence of his prior counsel; then retried the case in a two-week long jury trial, which resulted in an acquittal on all charges


American Cancer Society, Illinois Division

  • Leadership Counsel

Greater Chicago Food Depository

  • Lawyer's Committee "Lunch to End Hunger" Initiative

Gary Comer College Prep

Pro Bono

  • Participated in an unprecedented collaboration between the U.S. Department of Justice, the FBI, the Innocence Project and the National Association of Criminal Defense Lawyers aimed at identifying and remedying wrongful convictions based on flawed forensic work performed by the FBI Crime Lab in the areas of hair microscopy and composite bullet lead analysis
  • Succeeded in four different cases of overturning the wrongful convictions of men facing decades of imprisonment, including one individual who served time on death row

News & Resources



  • Illinois Super Lawyers, 2005-present
  • U.S. District Court for the Northern District of Illinois and the Federal Bar Association, Excellence in Pro Bono and Public Interest Service Award, 2003
  • National Innocence Project, Exceptional Service Award, 2012
  • Mid-Atlantic Innocence Project, Defender of Innocence Award, 2013

Academic Appointments

  • Loyola University School of Law, Adjunct Professor, Legal Writing and Appellate Advocacy