Matthew Siembieda is a Philadelphia litigation attorney with more than 30 years of experience in complex commercial litigation. Mr. Siembieda focuses his practice on patent and trade secret matters, environmental issues, Office of the Comptroller of the Currency (OCC) issues, commercial and securities fraud, insurance coverage, qui tam matters, taking claims, creditors' and debtors' rights, contract disputes, antitrust matters, cartel matters and merger litigation. He also defends clients accused of white collar crimes and Racketeer Influenced and Corrupt Organizations Act (RICO) violations.

Mr. Siembieda has substantial trial experience, including jury, and has handled competition matters before the European Commission. He counsels companies on litigation issues that relate to acquisitions and competition, represents clients in claims with and against the U.S. government, and conducts internal investigations.

With significant knowledge in laws from various jurisdictions including those in the U.S. and Europe, Mr. Siembieda advises global companies on compliance issues, including antitrust, Foreign Corrupt Practices Act (FCPA), market manipulation, trading with the enemy and privacy matters. In addition, he has significant experience handling intellectual property matters.

Mr. Siembieda is a visiting adjunct professor at Temple University's Beasley School of Law, lecturing on trade and compliance matters. Prior to entering private practice, he served as a judicial intern for the Hon. William Hastie at the U.S. Court of Appeals for the Third Circuit.

Representative Experience

  • Represented a bank and an investment products and services company in a series of class actions and other matters surrounding the Jersey City sale of its tax liens
  • Represented a corporation in recovering substantial funds from the U.S. Department of the Treasury in the U.S. Court of Appeals for the District of Columbia Circuit, surrounding the government's conduct in preventing creditors from recovering on a certain judgment
  • Represented clients in improper taking claims in the U.S. Court of Appeals for the Seventh Circuit, federal courts and the Court of Claims, including getting a state statute declared unconstitutional
  • Successfully represented various governmental entities in wide-sweeping matters concerning overcharging on bond issues
  • Counseled clients on various Foreign Corrupt Practice Act (FCPA) issues, state department International Traffic in Arms Regulations (ITAR) investigations, and various other issues such as trading-with-the-enemy regulations

  • Represented a leading energy company in preserving a contract to supply coke to an international steel company worth more than $3 billion
  • Successfully defended a company, in a cartel proceeding before EU Antitrust DG Competition cartel group, including through hearing client was the only respondent to win completely out of 28 parties
  • Represented insurance underwriters in a variety of complex litigation matters; obtained a $10 million judgment in a fraud/breach of trust case
  • Represented a long-distance telephone service provider in various complex commercial, patent and other intellectual property matters
  • Represented an airline in litigation to retain rights to certain aircraft later sold for profit in excess of $100 million
  • Represented a wire and cable manufacturer in commercial litigation and business advice
  • Represented a telecom equipment manufacturer in various patent and other intellectual property matters
  • Represented a bank as special litigation counsel in variety of bondholder class actions
  • Represented a financial services software provider as litigation counsel for commercial matters nationwide
  • Represented a corporation in commercial disputes; obtained an $11 million jury verdict
  • Successfully represented a healthcare insurance company to conclusion in class action

  • Represented law firms in issues concerning lateral partners
  • Represented corporations in internal investigations
  • Represented a football league in negotiations and commercial matters
  • Handled a number of competition and international cartel investigations
  • Successfully defeated an attempt to enjoin the merger of healthcare entities


  • University of Pennsylvania Law School, J.D.
  • Canisius College, B.A.
Bar Admissions/Licenses
  • Pennsylvania
Court Admissions
  • U.S. Supreme Court
  • U.S. Court of Appeals for the Third Circuit
  • U.S. Court of Appeals for the Seventh Circuit
  • U.S. Court of Appeals for the Federal Circuit
  • U.S. District Court for the Eastern District of Pennsylvania
  • U.S. District Court for the Middle District of Pennsylvania
  • All State Courts in Pennsylvania
  • Pennsylvania Bar Association
  • Philadelphia Bar Association
Honors & Awards
  • Holland & Knight Pro Bono All-Star, 2020, 2021
  • Pennsylvania Super Lawyers magazine, General Litigation, 2004, 2006-2007, 2009