Stephen A. Mohr, P.C.
Overview
Stephen A. Mohr is an antitrust & competition partner in the Washington, D.C., office of Kirkland & Ellis LLP. Prior to joining Kirkland, Stephen served as Assistant Director in the Federal Trade Commission’s (FTC) Bureau of Competition, where he led the Mergers I Division. He oversaw merger investigations and led major litigations across a variety of industries, including pharmaceuticals, medical devices, pharmacies, PBMs, clinical laboratories, dialysis, next-generation medical technologies, veterinary clinics, healthcare advertising, defense, aviation, and consumer, industrial and life sciences products.
During his tenure as Assistant Director, he supervised all aspects of the Division’s merger investigations and enforcement actions. He has extensive courtroom experience and was involved in shaping the FTC’s merger enforcement program in recent years, including the development and prosecution of several of its most groundbreaking enforcement actions such as those involving innovation competition, the acquisition of nascent competitors by dominant firms, portfolio leveraging, serial acquisitions, vertical mergers and the litigation of behavioral remedies. Stephen also oversaw and negotiated complex consent agreements in various industries. He led the Division’s engagement with critical stakeholders, including the Department of Justice, the Department of Defense, the Food and Drug Administration (FDA), Congress, state attorneys general and foreign antitrust regulators.
He frequently speaks about antitrust issues related to pharmaceutical, medical device and life science mergers, and is a recipient of numerous FTC awards, including the prestigious Brandeis Award for outstanding litigators.
Experience
Representative Matters
Prior to joining Kirkland, as the Assistant Director of the FTC’s Mergers I Division, Stephen oversaw the review of mergers in industries including pharmaceuticals, medical devices, pharmacies, PBMs, next-generation medical technologies, clinical laboratories, dialysis, veterinary clinics, healthcare advertising, defense, aviation and consumer, industrial and life sciences products. Among other major matters during his tenure, the Mergers I Division litigated the government’s first successful challenge of a vertical merger in decades (Illumina/Grail), won a preliminary injunction in a healthcare advertising merger challenge following a two-week federal court trial (IQVIA/PMI), brought two of the first litigated pharmaceutical merger challenges in decades (Amgen/Horizon and Sanofi/Maze) and litigated the first defense merger challenge in decades (Lockheed/Aerojet). In addition, Stephen directed significant investigations and actions that resulted in abandoned mergers, as well as negotiated and secured consent orders in the pharmaceutical and veterinary industries.
Prior to serving as the Assistant Director in Mergers I, Stephen was a Deputy Assistant Director, a Counsel to the Director and a lead attorney at the Commission. In these roles he supervised, led and participated in a wide range of investigations and litigations. For example, he was co-lead trial counsel in the FTC’s successful challenge to the Otto Bock/Freedom merger in administrative court and was part of the trial team in Steris/Synergy, the first potential competition case in more than 30 years, as well as the Sysco/U.S. Foods and LabCorp/Westcliff litigations. He has held critical roles in many of the Commission’s most important litigations of the past decade, including cross-examining economic experts in four different trials.
Prior to joining the FTC in 2010, Stephen was an associate at another law firm in Washington, D.C., and clerked for the Honorable Karen LeCraft Henderson on the United States Court of Appeals for the District of Columbia Circuit and the Honorable Stephen V. Wilson on the United States District Court for the Central District of California.
Clerk & Government Experience
Law ClerkHonorable Karen LeCraft HendersonUnited States Court of Appeals for the District of Columbia Circuit2007–2008
Law ClerkHonorable Stephen V. WilsonUnited States District Court for the Central District of California2006–2007
Prior Experience
Federal Trade Commission
- Assistant Director, Mergers I Division, 2021–2024
- Deputy Assistant Director, Mergers I Division, 2020–2021
- Counsel to the Director, 2020–2020
- Staff Attorney, Mergers I Division, 2010–2020
Gibson, Dunn & Crutcher LLP
- Associate, 2009–2010
International Justice Mission, Bangalore, India
- Legal Fellow, 2008–2009
More
Thought Leadership
Publications
Author, “The Closest Competitor Is Not the Only Competitor,” FTC Competition Matters, 2019
Author, “Effective Presentation of Expert Testimony for the Government in a Merger Litigation,” Antitrust Magazine, Vol. 31, No.1, 2016
Speaking Engagements
“Pharma Under the Antitrust Microscope,” 73rd Antitrust Law ABA Spring Meeting Panel, 2025
“Navigating the New Merger Guidelines in Pharmaceuticals,” GCR Antitrust Conference, 2024
“Merger Developments,” Bill Kovacic Antitrust Salon Presented by Concurrences, 2024
“New Competition Theories in Life Sciences Mergers,” ABA Antitrust in Healthcare Law Conference, 2024
“Nascent and Potential Competition: Issues and Considerations,” Hal White Antitrust Conference, 2024
“Sanofi / Maze: An A-maze-ing Expansion of the Nascent Competition Doctrine?” ABA Antitrust Law Section Panel, 2024
“Just What the Doctor Ordered? FTC Treatment of Medical Device Mergers,” ABA Antitrust in Healthcare Law Conference, 2021
“Presenting Economic Evidence in Merger Trials,” 64th Antitrust Law ABA Spring Meeting Panel, 2017
“Identifying, Hiring, and Managing Experts,” ABA Be the Master Training Series, 2017
Recognition
Recognized in The Legal 500 U.S. for Antitrust: Merger Control, 2025
Stephen is the recipient of numerous Federal Trade Commission honors, including in 2015, the Louis D. Brandeis Award, given annually to a single FTC attorney for outstanding service in litigation, numerous Janet Steiger Team Awards and the Distinguished Service Award.
Credentials
Admissions & Qualifications
- District of Columbia
Courts
- United States Court of Appeals for the District of Columbia Circuit
- United States District Court for the Central District of California
Education
- Harvard Law SchoolJ.D.magna cum laude2006
- University of North Carolina at Chapel HillB.S., Business & Economics2003
News &
Insights
- Press Release Kirkland Advises Worldpay and GTCR on Sale of Worldpay to Global Payments for $24.25B in Conjunction with Transformative Three-Way Transaction
- Press Release Kirkland Advises BC Partners on Acquisition of Majority Stake in PetLab Co.
- Press Release Kirkland Advises KKR-Backed Kito Crosby on $2.7 Billion Sale to Columbus McKinnon
- Press Release Kirkland & Ellis Expands Antitrust Practice with Former Federal Trade Commission Attorney Stephen Mohr