Since joining the firm at its inception in 1997, Bill’s main practice area has been complex commercial litigation, including both civil trials and arbitration. Bill, the Vice Chairman of the firm, is a 2016 American Lawyer Litigator of the Year, ranked by Chambers & Partners, a three-time winner of The AmLaw Litigator of the Week, among 31 lawyers in the LawDragon 500 for each of the last ten years, and a Fellow of the American College of Trial Lawyers. Global Competition Review writes, "Arguably no antitrust lawyer in recent memory has had as much success for both plaintiffs and defendants as Boies Schiller partner Bill Isaacson.”
In 2015, after a three-week jury trial in the District of Nevada, Bill–together with BSF co-counsel Karen Dunn–won a $50 million verdict, later increased to $124 million in a judgment, for Oracle for software copyright infringement and state law violations. In 2014, in O’Bannon v. NCAA, he won significant attention for his cross-examinations of NCAA witnesses, obtaining a historic victory for college athletes. In the same year, Bill served as trial counsel, with Karen Dunn, in a high-profile antitrust class action in the portable music industry, winning a complete defense verdict. In 2013, Bill was also trial counsel in the first antitrust action against Chinese companies for cartel conduct relating to products sold in the United States, winning a $162 million judgment, and $33 million from settling defendants.
The publication Lawdragon has recognized Bill as one of 30 lawyers who for 10 years has been listed as one of the 500 leading lawyers in the U.S. and writes: "It’s nearly impossible to find a more reliable antitrust litigator than Isaacson, who has successfully handled several of the most high-profile cases in the past two decades.” Law 360 has named Bill as a Competition MVP both in 2015 and 2018 and Titan of the Plaintiff Bar, and a Litigator of the Week by Global Competition Review. Legal 500 describes him as a “leader” at the firm “with many successes to his credit” who has a "brilliant knowledge of international arbitration."