Debbie Feinstein heads Arnold & Porter's Global Antitrust group, and brings a wealth of experience to her practice in advising clients on a range of antitrust challenges before US antitrust authorities. She recently re-joined the firm from the US Federal Trade Commission (FTC), where she was Director of the Bureau of Competition. In that capacity, she was responsible for supervising the investigation and enforcement of the US antitrust laws against anticompetitive mergers and conduct. During her tenure from 2013 to 2017, the FTC had substantial litigation success and a number of major merger wins, including challenges to Sysco Corp.'s acquisition of rival US Foods Inc., and Staples Inc.'s merger with Office Depot Inc. She had previously served at the FTC from 1989 to 1991 as Assistant to the Director of the Bureau of Competition and Attorney Advisor.

Throughout her career, Ms. Feinstein has focused on merger and acquisition reviews by antitrust enforcement agencies in the United States and globally, as well as civil investigations and litigation. Her industry experience is broad, and includes retail, food, consumer products, healthcare, chemicals, and automotive parts, among others. She was an associate at Arnold & Porter from 1987 to 1989 and from 1991 to 1995. Later, as a partner, she led the firm's US Antitrust group from 2010 to 2013.

Ms. Feinstein has been consistently lauded as a leading practitioner by Chambers USA and other ranking publications. The National Law Journal named her one of the most influential women lawyers in America and Global Competition Review recognized her as global "Lawyer of the Year" and named her to its international list of the "Top 100 Women in Antitrust." She has also been ranked by Super Lawyers as being among the top 50 women lawyers in Washington, DC.


  • Bristol-Myers Squibb in its $4.1 billion acquisition of Turning Point Therapeutics.
  • Pfizer in its $6.7 billion acquisition of Arena Pharmaceuticals.
  • AbbVie in its $550 million acquisition of medical device company, Soliton Inc.
  • Billie in the sale of its business to Edgewell.
  • Fitbit Inc. on its $2.1 billion sale to Google.
  • Abbvie in its $63 billion acquisition of Allergan, the manufacturer of the well-known medication Botox. The FTC approved the transaction with modest divestitures.
  • Bristol-Myers Squibb in its $90 billion acquisition of Celgene and the related $13.4 billion divesture of Celgene's OTEZLA® program to Amgen.
  • Reyes Holdings in obtaining FTC clearance for the $2 billion sale of its Reinhart FoodService business to Performance Food Group.
  • Panasonic in establishing Prime Planet Energy & Solutions, Inc., a JV with Toyota specializing in automatic prismatic batteries.
  • Cisco Systems, Inc. in its $1.9 billion acquisition of cloud-based unified communications provider BroadSoft, Inc., which was cleared without a Second Request by DOJ and without conditions worldwide.
  • Sony Corporation of America and Sony/ATV Music Publishing in obtaining antitrust clearance for the client's $2.2 billion purchase of the music publishing business of EMI.
  • AT&T Inc. in its successful $85.4 billion stock-and-cash acquisition of Time Warner Inc. AT&T successfully defended the first vertical merger trial and appeal in decades.
  • Onex and SMG, a facility management company, in its merger with AEG Facilities to create a global facility management and venue services company.
  • Rent-a-Center in its proposed acquisition by Vintage Capital.
  • NxStage Medical, Inc. in connection with its $2 billion sale to Fresenius Medical Care Holdings, Inc.
  • General Electric Co. and NBC Universal in connection with the formation of the Comcast-NBCU joint venture investigated by DOJ, FCC, and various state attorneys general.
  • General Electric Co. in its $4.3 billion acquisition of Avio, an aircraft engine parts supplier.
  • Boston Scientific Corporation, the world's largest medical device company dedicated to less-invasive medicine, in its $27 billion acquisition of Guidant. The transaction also included a $4 billion pre-closing divestiture to Abbott Laboratories of Guidant's endovascular solutions and vascular intervention businesses but allowed Boston Scientific to retain rights with respect to Guidant's drug-eluting stent portfolio.
  • Loews Cineplex Entertainment Corporation in its merger with AMC Entertainment Inc. Together the firms will own or operate 334 theatres nationwide. The matter was resolved with the DOJ and various state attorneys general with the divestiture of only 10 theatres.
  • The Kroger Co. in its $13.5 billion merger with Fred Meyer, Inc., successfully negotiated with the FTC to require the divestiture of only 8 stores. The combined company became, at the time, the largest grocery retailer in the United States.
  • General Electric Corporation's $2.1 billion acquisition of Instrumentarium OYJ, a manufacturer of high-technology medical equipment.
  • Phillip Morris and Kraft in their $18.9 billion acquisition of Nabisco Holdings Corporation, creating the world's largest food company. Negotiations with the FTC resulted in the divestiture of only minimal assets.
  • Occidental Chemical Company in the $360 million purchase of Vulcan Materials Company's chemical assets.
  • PepsiCo in its $14 billion acquisition of The Quaker Oats Company. The merger strengthened PepsiCo's food businesses and added Gatorade, the leading sports drink brand, to its portfolio.
  • Meritor Automotive in its merger with Arvin Industries to become ArvinMeritor, a leading automotive industry supplier.
  • Genzyme's acquisition of Novazyme. The acquisition combined the only two companies performing research and development on a rare disease.
  • Unilever in the acquisition of Alberto Culver and in the sale of its Lawry's & Adolph's spice/seasonings business to McCormick .



LMG Life Sciences Guide
"Life Science Star"—Mergers & Acquisitions (2021–2022)
"Life Science Star"—Antitrust (2021–2022)
Best Lawyers
Antitrust (2012, 2020-2023)
Who's Who Legal
Competition (2011, 2020, 2022)
Thought Leaders—Competition (2018, 2020, 2022)
Thought Leaders Global Elite—Competition (2022)


  • JD, Harvard Law School
  • AB, University of California, Berkeley
  • District of Columbia
Government & Military Service
  • Director of the Bureau of Competition, US Federal Trade Commission (2013-2017)
  • Assistant to the Director of the Bureau of Competition and Attorney Advisor, US Federal Trade Commission (1989-1991)

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