DePaul University College of Law, J.D.
  • magna cum laude; Order of the Coif; Recipient of five American Jurisprudence Awards
University of Wisconsin–Madison, B.A.

Bar Admissions

Professional Affiliations

American Bar Association

Chicago Bar Association

  • Young Lawyer’s Section
    • Careers Committee for Young Lawyer’s Section, Co-chair
  • Federal Trial Bar Training Course, Teacher
  • Committee on Attorney Malpractice, Co-chair
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Mr. Palmersheim is an accomplished trial and appellate lawyer who represents clients across the country in complex business disputes, with particular experience in the areas of antitrust, intellectual property, fiduciary and professional liability litigation.  For more than 20 years, he has represented clients in jury and bench trials before state and federal courts, appeals, arbitrations, and contested evidentiary hearings.  His clients include public and private corporations, large law and accounting firms, trustees, directors and officers, funds, and entrepreneurs.   

  • Represents a leading global products manufacturer in an antitrust lawsuit alleging that several banks and metal trading companies conspired to fix the price of primary aluminum sold in North America
  • Handles cases and argues appeals in state and federal courts, as well as arbitrates cases before the American Arbitration Association, FINRA and the International Institute for Conflict Prevention and Resolution
  • Counsels clients on legal aspects of their business strategies, mechanisms for resolving disputes while reducing legal exposure and expenditures, and means for achieving business objectives through litigation


Antitrust Litigation

  • Defended a technology company against monopolization claims involving the market for electronic article surveillance products; resolving the lawsuit, which included a multi-day Daubert hearing resulting in the Special Master recommending exclusion of expert opinions for approximately two-thirds of plaintiff’s claimed damages
  • Defended medical device manufacturer against bid-rigging claims
  • Defended telecommunications provider against claims for illegal tying in the market for high speed data transmission 
  • Defended battery manufacturer against monopolization claims brought by start-up competitor in the market for industrial batteries and defeated claims on summary judgment

Intellectual Property Litigation

  • Argued in the Federal Circuit and won reversal of an “exceptional case” finding under Section 285 of the Patent Act, and although the judgment was later reversed and remanded to District Court following the U.S. Supreme Court decisions in Octane and Highmark, the case is again on appeal before the Federal Circuit 
  • Numerous representations of hand-tool manufacturer in design patent infringement claims and lawsuits
  • Represented technology company in patent infringement lawsuit against domestic and foreign infringer and successfully resolved lawsuit
  • Represented a technology company in a trade secret case against former employees under Minnesota Trade Secrets Act and obtained enforcement of restrictive covenants
  • Represented brokerage firm in numerous matters under Illinois Trade Secrets Act
  • Represented wire and cable company in lawsuit under the Georgia Trade Secrets Act and obtained injunction in Georgia state court

Professional Liability, Fiduciary, and Fraud Litigation

  • Defended Am Law 50 law firm on claims brought by former client relating to False Claims Act litigation, obtained summary judgment on plaintiff’s claims and settled law firm’s counterclaim for unpaid fees prior to trial
  • Defended Am Law 10 firm in lawsuit alleging patent litigation malpractice and successfully resolved the lawsuit prior to trial
  • Defended Am Law 20 firm against claims that the firm’s attorneys were negligent in estate planning for multimillion dollar estate and obtained dismissal of all claims, which was affirmed on appeal
  • Defended Am Law 10 firm against claims by former partner of the firm who sought indemnification for malpractice claims brought against him (dismissal of malpractice and third-party claims was affirmed on appeal)
  • Represented Am Law 10 law firm in claims by client that the firm was negligent in $25 million loan transaction (matter was resolved before the firm’s client filed suit)
  • Defended Am Law 50 firm in lawsuit alleging that the firm was negligent in the negotiation of a collective bargaining agreement
  • Represented former general counsel of hedge fund management company with respect to investigation and claims by hedge fund liquidators relating to the bankruptcy of broker-dealer, Refco, Inc. (the matter was resolved without our client being sued and with the liquidators paying a substantial portion of attorneys’ fees our client incurred responding to claims and investigation)
  • Defended auditing firm with respect to fraud claims arising out of alleged Ponzi scheme orchestrated by auditing firm’s former client
  • Obtained complete dismissal of lawsuit brought by LaSalle National Bank against accounting firm, which alleged that the accounting firm had conspired to defraud the bank in connection with loans totaling in excess of $25 million
  • Obtained complete dismissal of lawsuit brought by golf equipment manufacturer against accounting firm, which alleged that the accounting firm negligently audited company’s financial statements and conspired with corporate directors to hide losses exceeding $20 million
  • Obtained verdict for defendants on claims brought by trustee over the ownership of commercial farm land
  • Represented metals trading company in fraud, fiduciary duty and conspiracy trial; obtained a multi-million dollar jury verdict, including substantial punitive damages
  • Represented multinational corporation in several arbitrations, including hearing,  asserting fraud against financial and banking institutions, resulting recoveries totaling in excess of $50 million
  • Defended sellers of a privately held corporation against claims of fraud with purported damages in excess of $70 million and resolved all claims prior to trial
  • Represented multinational corporation in Delaware Chancery Court on claims that defendants defrauded client in connection with a $20 million sale of a manufacturing business
  • Obtained $1.7 million judgment for an energy services company in a breach of contract case, including more than $500,000 in interest and attorneys' fees, and then successfully pursued fraudulent transfer and successor liability claims against the judgment debtor's principals, resulting in a judgment against them for approximately $2.8 million, which included yet additional interest and attorneys' fees (this case was affirmed by the Court of Appeals for the Seventh Circuit)
  • Defended franchisees against fraud and racketeering claims, and obtained summary judgment on plaintiff’s claims
  • Currently defending Cayman Island real estate company and its principals in lawsuit claiming racketeering, fraud, and breach of fiduciary duty


Pro Bono

  • Cabrini Green Legal Aid Society, representing disadvantaged individuals in criminal and civil matters

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Seminars & Events


  • Illinois Super Lawyers, 2005-2006 and 2013-present
    • Selected among the Top 100 Super Lawyers in Illinois, 2014-2015
  • Leading Lawyers Network, 2012-present
  • Honored by BTI Consulting Group as a 2016 Client Service All-Star