Sean M. Koller

Sean Koller represents clients in a variety of industries in complex business disputes. Whether handling a pre-litigation negotiation, representing a client in a mediation, federal or state court litigation, arbitration, a government investigation or inquiry, or working out a settlement, Sean brings the experience needed to resolve matters efficiently and effectively.

Sean has handled complex commercial suits, antitrust and healthcare disputes, derivative suits, tort disputes, and contractual claims, among other matters. He has represented clients in cases before the American Arbitration Association (AAA), JAMS, the American Health Law Association, and other alternative dispute resolution tribunals.

Additionally, Sean has successfully defended individuals and corporations against government investigations conducted by the Department of Justice, Securities and Exchange Commission, Public Company Accounting Oversight Board, State Attorneys General, and other state and federal government agencies. Both public corporations and nonprofit organizations also turn to Sean to help guide them through internal investigations to identify and resolve problems.

Sean listens closely to his clients, making certain that he understands their business and industry, and the specific problems they face. Armed with that knowledge, he crafts solutions that work best for them. In litigation, Sean applies his knowledge of the courts and their procedures and considers the opposing counsels’ arguments and strategy. Then he devises a plan of action to position his clients for success. Regarded as diligent, intelligent, and analytical, he stays ahead of the curve, keeping current on new laws and regulations, especially in Illinois, and how they may impact his clients.

In addition to his active practice, Sean engages in pro bono efforts; these include representing nonprofit organizations in internal investigations, prisoners in post-conviction hearings and suits, and individuals in Public Trust Doctrine suits.

Before joining the firm, Sean was an associate at McDermott Will & Emery LLP, an Am Law 25 law firm. He brings that “big law” experience to bear when representing Sperling Kenny Nachwalter clients.