William H. Roberts


William Roberts concentrates his practice in the field of antitrust litigation and counseling, and complex commercial litigation, including class actions, trials and appeals in federal and state courts principally in the following areas:

  • Antitrust litigation and counseling
  • International cartel litigation
  • Defamation and First Amendment issues
  • Professional responsibility and legal malpractice

Bill previously served as General Counsel of Blank Rome LLP.


  • Represented, in many cases, corporations and individuals in civil and criminal antitrust litigation, including international cartel cases and defense of private class actions alleging price-fixing.
  • A steel corporation before the Supreme Court of the United States, in a stockholders' derivative action involving First Amendment protection of corporate advertisements under federal election campaign finance laws and implied private rights of action. 
  • A major oil company as amicus curiae, in landmark First Amendment cases in the Supreme Court of the United States.
  • Residential builders, in labor/antitrust/RICO treble-damage action against local unions involving union actions at residential development sites.
  • A regional transit authority, in litigation related to standards for paid non-commercial advertising concerning an alleged public health issue, and enforceability of rules regulating time, place and manner of constitutionally protected activities throughout its rail, subway, bus and elevated rail stations paid areas, and platforms.
  • A port authority, in public forum doctrine litigation with unions over access to major interstate bridge for march and demonstration.
  • An electric utility, in appellate tax matters.


2021–2024, Antitrust Law in Philadelphia, listed in The Best Lawyers in America©



  • American Bar Association
  • Philadelphia Bar Association
Professional Activities

Bill is trustee of the Philadelphia Chamber Music Society and Marlboro Music School and Festival. He also serves on the board of directors for the Tempesta di Mare Baroque Chamber Orchestra. Bill is chairman of the board of trustees for the Harvard Review of Philosophy.



  • Harvard University, AB, cum laude
  • University of Pennsylvania Law School, JD
  • French
  • Greek
  • Latin