William H. Stallings is an Antitrust & Competition partner in Mayer Brown's Washington DC office. Previously, he spent 17 years at the US Department of Justice’s (DOJ) Antitrust Division, culminating with his service as the Chief of the Transportation, Energy, and Agriculture Section. Bill advises clients on a full range of competition and consumer protection issues, including DOJ/FTC merger compliance and litigation; private antitrust litigation, including class actions; and global and US government competition and consumer protection investigations. For his outstanding service in antitrust enforcement, the DOJ awarded Bill the prestigious Neil E. Roberts Award (2015). In 2016, the National Law Journal recognized Bill as an Antitrust Trailblazer.
Since joining Mayer Brown in 2015, Bill has handled several high-profile client matters, including serving as lead antitrust counsel in a multibillion-dollar merger that closed successfully following a DOJ second request investigation and private litigation. Bill is also active in the following capacities:
- Non-Governmental Advisor (on behalf of the US DOJ) to the International Competition Network (ICN), an international organization of more than 100 competition agencies with the common aim of addressing practical antitrust enforcement and policy issues.
- Co-chair of the new Antitrust, Competition and Consumer Protection Committee of the American Bar Association’s (ABA) Air & Space Forum.
- Vice-chair of the Transportation and Energy Industries Committee of the ABA's Antitrust Section.
Bill is a co-leader of Mayer Brown's Aviation industry group and assists clients (including airlines, airports, executives, handlers and investors) in navigating complex competition issues in the aviation sector. He is familiar with the approaches of the most active competition authorities on the assessment of mergers, alliances and code-sharing agreements in this sector.
As chief of the Transportation, Energy, and Agriculture Section at the DOJ, Bill was responsible for civil antitrust enforcement, competition advocacy and competition policy in areas such as domestic and international aviation, electricity, oilfield services and agricultural commodities. He supervised the section's investigations of antitrust violations, managed dozens of second-request merger matters, shaped substantive analyses, engaged with international antitrust authorities, presented matters to DOJ leadership and litigated enforcement actions. Bill was appointed assistant chief of the section in 2005 and chief in 2011.
Learn more about the high-profile and precedent-setting matters Bill handled during his DOJ career.