Leslie John

Leslie E. John


Leslie E. John is the Practice Leader of Ballard Spahr's Antitrust and Competition Group and Co-Leader of its False Advertising Litigation Team. Leslie concentrates on antitrust and complex litigation, and she has represented clients—many of them in the pharmaceutical and health care industries—in federal and state courts and before the U.S. Department of Justice and Federal Trade Commission. She also advises on antitrust issues in mergers and acquisitions, including securing pre-merger clearance under the Hart-Scott-Rodino Act, and counsels clients on antitrust compliance and risk management.

Leslie is recognized for her antitrust acumen in Chambers USA and is among Benchmark Litigation’s Top 250 Women in Litigation nationwide. Chambers USA described her as “methodical, very strategic and highly intellectual. She also communicates very effectively.” Leslie has substantial class action experience and was named “Litigator of the Week” by Global Competition Review in July 2015 for securing the decertification of an indirect purchaser class in a pharmaceutical antitrust case. She was honored as the “Best of the Bar” by the Philadelphia Business Journal in 2021 and as a “Top Women in Law” by The Legal Intelligencer in 2016.


Representative Matters

  • Successfully represented a real estate company that develops, leases and manages retail, concession and food space in a suit by a leading concessionaire alleging antitrust and related state law violations. Plaintiff alleged that our client’s leases, which purportedly contain a “pouring rights” provision requiring concessionaires to sell certain beverages, was an unlawful tying arrangement. The Eastern District of Pennsylvania granted our motion to dismiss and on appeal, the Third Circuit issued a precedential decision affirming the dismissal of the case.
  • Successfully defended nonprofit physician-led independent evaluation organization against an antitrust class action lawsuit filed by four physicians. Plaintiffs alleged that the organization’s requirements for continuing certification violated the antitrust laws and the federal civil RICO laws. The Third Circuit affirmed on appeal the dismissal of the case.
  • Representing one of the largest agricultural companies in the U.S. in nearly two dozen now consolidated class actions alleging a group boycott by agricultural companies, large wholesalers, and large retailers not to do business with on-line retailers of “crop inputs,” specifically seeds and various crop protection products.


Professional Highlights

Professional Activities

Fellow, Litigation Counsel of America

Philadelphia Bar Foundation, President, 2019-2020; Vice President, 2007-2018; Board of Trustees, 2010-present; Secretary, 2013-2016; Co-Chair, 50th Anniversary Gala

Philadelphia Diversity Law Group, Co-President, 2019-present; Vice President, 2016-2018; Board of Directors, 2011-present

Forum of Executive Women, 2017-present

WOMEN'S WAY (nation's oldest women's funding federation), General Counsel, 2007-present

Ballard Spahr's Diversity, Equity, and Inclusion Council, Member

Recognition & Accomplishments

Philadelphia Business Journal, "Best of the Bar," 2021

The Legal 500 US, Antitrust - Civil litigation/class action - defense, 2019-2024; Antitrust - Civil litigation/class action - plaintiff, 2019, 2020

Chambers USA, antitrust law (Pennsylvania), 2014-2024

Speaking Engagements

Speaker, Hot Topics in NY Antitrust: Class Certification and Fraud-Based Antitrust Investigations," New York City Bar's Antitrust & Trade Regulation Committee, April 30, 2018 

Speaker, "Post-Lamictal, Loestrin & Nexium: What Violates Section One Reverse Payment Law, and What Does Not?" HarrisMartin's Pharmaceutical Antitrust Litigation Conference: Generic Drugs & Emerging Price-Fixing cases, March 3, 2017

Speaker, "Everyday Antitrust Issues: You Don’t Know What You Don't Know," Ballard Spahr CLE Program, October 12, 2017


Co-author, "FTC's Hospital Merger Enforcement Hangs in the Balance," Law360, June 16, 2016 

Co-author, "2 Assumptions Shape 3rd Circ. Reverse Payment Case," Law360, November 20, 2014

Co-author, "'Reverse Payment' Realities: Challenging Pervasive Assumptions Underlying Calls for Broad Antitrust Scrutiny of Patent Infringement Settlements," Bloomberg BNA Antitrust & Trade Regulation Report, November 14, 2014



University of California, Berkeley, School of Law (J.D. 1987)
Associate Editor, California Law Review
Member, Moot Court Board

University of California, Berkeley (A.B., summa cum laude, 1984)




U.S. Supreme Court

U.S. Court of Appeals for the Fourth Circuit