William O’Brien

Education Profile

  • Duke Law School (2015)
  • Chicago-Kent
    College of Law (2014)
  • University of Illinois (2009)

State Court Admissions

  • Illinois

William J. O’Brien joined Cafferty Clobes Meriwether & Sprengel LLP in 2016 and is based in its Chicago, Illinois office.  William focuses his practice on financial services, corporate law, and antitrust litigation. Previously, William was an analyst at the Financial Industry Regulatory Authority (FINRA) in the Exchange-Traded Products Division.  In that role, he conducted market surveillance to identify and report manipulation and abuse.  William is passionate about financial markets, regulation, and technology.

Mr. O’Brien graduated from the University of Illinois at Urbana-Champaign in 2009 with a degree in history and political science. He received his J.D. from Chicago-Kent College of Law in 2014.  He earned his LLM in entrepreneurial law from Duke Law School in 2015.  He is admitted to practice in the state of Illinois.

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