Sergei Zaslavsky


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Sergei Zaslavsky is an antitrust attorney with broad experience in trials, regulatory merger reviews, conduct investigations, antitrust audits, and antitrust counseling. Sergei effectively represents his clients by being both detail-oriented and strategic, and by studying his clients’ businesses to understand how legal questions intersect with marketplace realities. In doing this, he is able to synthesize antitrust doctrine, economics, and facts into advocacy that is both rigorous and intuitive.

Sergei is a veteran of three federal trials and one arbitration hearing. He has taken the testimony of executives, deposed numerous fact and expert witnesses, second-chaired direct and cross examinations of world-famous economists, and argued in court. In 2019, the National Law Journal named Sergei as a “DC Rising Star,” an award recognizing “the Washington, DC, region’s 40 most promising lawyers age 40 and under.”


Honors & Awards

  • Selected as one of The National Law Journal’s 2019 “DC Rising Stars”


Bar Admissions

  • District of Columbia
  • Maryland


  • Harvard University, J.D.: magna cum laude
  • Dartmouth College, A.B., Economics: summa cum laude

Professional Activities


  • ABA Antitrust Law Section Leadership
  • ABA Antitrust Law Section Our Curious Amalgam Podcast

Author / Co-Author

Contributing Author

  • Antitrust Law Developments Update, ABA (2019)
  • Consumer Protection Law Developments, ABA (2016)


  • Our Curious Amalgam, “What’s the Hubbub About No-Poach? Recent Antitrust Enforcement in Labor Markets,” Co-Host, ABA (2020)
  • Our Curious Amalgam, “Who Is Ready for 2021? Year in Review: Part 1,” Host, ABA (2020)
  • Our Curious Amalgam, “Who Does Antitrust Work For? An Exploration of Labor Antitrust” Co-Host, ABA (2020)
  • Our Curious Amalgam, “All Bundled Up? Making Antitrust Sense of Product Bundles and Clusters,” Co-Host, ABA (2020)
  • Our Curious Amalgam, “What is the Relationship Between Privacy and Competition? A Conversation with Commissioner Noah Phillips” Co-Host, ABA (2020)
  • Our Curious Amalgam, “Breaking News Special:  Draft Vertical Merger Guidelines,” Co-Host, ABA (2020)
  • Our Curious Amalgam, “Why Does it Matter? The Role of Big Data in Antitrust” (interview with Daniel Sokol), Co-Host, ABA (2020)
  • Our Curious Amalgam, “Why the Techlash? Antitrust Policy and Big Tech” (interview with Hal Varian), Co-Host, ABA (2019)
  • Our Curious Amalgam, “What’s The State of Things:  3 Things I Keep, 3 Things I Change” (interview with Josh Wright), Co-Host, ABA (2019)
  • Our Curious Amalgam, “What is the Secret Sauce Behind Developing a Complaint” (interview with Melinda Coolidge) Co-Host, ABA (2019)
  • Our Curious Amalgam, “Can We Have Mergers Without Tears:  Understanding the Basics of Merger Review” (interview with Mike Keeley), Co-Host, ABA (2019)


  • ABA Fundamentals of Antitrust Economics Series: Statistical Significance (November 2018)
  • ABA Consumer Protection Update (October 2015)
  • Defended AT&T and Time Warner against DOJ’s challenge of their historic merger. The trial was characterized as a “sweeping victory for AT&T” by The Wall Street Journal. United States v. AT&T Inc., 310 F. Supp. 3d 161, 164 (D.D.C. 2018), aff’d sub nom. United States v. AT&T, Inc., 916 F.3d 1029 (D.C. Cir. 2019).
  • Prepared key fact witnesses and second-chaired economic experts’ direct and cross examinations in US Airways v. Sabre, an eight-week trial that resulted in a favorable jury verdict and garnered Global Competition Review’s “Litigators of the Week” award for the O’Melveny trial team. US Airways, Inc. v. Sabre Holdings Corp., No. 11 CIV. 2725, 2017 WL 1064709 (S.D.N.Y. Mar. 21, 2017), remanded, 938 F.3d 43 (2d Cir. 2019).
  • Represented US Airways in litigation against the DOJ in its merger with American Airlines.
  • Representing a major bank in a class action involving allegations of collusion to inflate interest rates on bonds.
  • Representing Global Music Rights in antitrust litigation against the Radio Music Licensing Committee.

Alerts and Publications

FTC Announces New 2022 HSR Reporting Thresholds and Renews Call to Congress for Additional Funding

January 25, 2022

Prompted by Sweeping Executive Order on Competition, New Leadership at US Antitrust Agencies to Launch Review of Merger Guidelines; Similar Initiatives in Europe and China May Signal Greater Convergence in Enforcement Across Jurisdictions

July 26, 2021

Unanimous Supreme Court Affirms Injunction Barring NCAA Rules that Limit Education-Related Compensation to Student Athletes

June 30, 2021

Supreme Court Holds That FTC Cannot Sue for Monetary Relief: AMG Capital Management v. FTC

April 26, 2021

Senator Klobuchar Unveils Broad New Proposed Antitrust Legislation

February 8, 2021

FTC Adjusts New 2021 HSR Reporting Thresholds Downward

February 3, 2021

The Department of Justice Antitrust Division Brings First-Ever Criminal No-Poach Case

January 22, 2021

Germany Strengthens Antitrust Enforcement Powers to Rein in Big Tech

January 19, 2021

China Expands National Security Review of Foreign Investments

January 12, 2021

European Commission Plan to Reform Europe’s Digital Space - Part 2 - Draft Digital Services Act

December 23, 2020

European Commission Plan to Reform Europe’s Digital Space - Part 1 - Draft Digital Markets Act

December 21, 2020

The Department of Justice Antitrust Division Brings First-Ever Criminal Labor Market Collusion Case

December 17, 2020

New Guidelines Clarify When Antitrust Division Will Consider Using Arbitration

December 1, 2020

The UK National Security and Investment Bill: Strengthening scrutiny of investment in the UK and introducing the UK’s first mandatory notification regime

November 20, 2020

ABA Antitrust Law Podcast: Who Does Antitrust Work For? An Exploration of Labor Antitrust

November 2, 2020

The Deal: Merger Control and Privacy - The Right Tool for the Job?

October 12, 2020

ABA Antitrust Law Podcast: All Bundled Up? Making Antitrust Sense of Product Bundles and Clusters

October 12, 2020

China Publishes “Unreliable Entities” Rules Targeting Foreign Enterprises

September 22, 2020

DOJ Issues Letter Encouraging IEEE to Change Policy on Standard Essential Patents

September 18, 2020

Hong Kong Competition Tribunal Approves First Cartel Settlement

August 13, 2020

ABA Antitrust Law Podcast: What is the Relationship Between Privacy and Competition? A Conversation with Commissioner Noah Phillips

August 10, 2020

Congress Reauthorizes ACPERA and Repeals Sunset Provision

July 17, 2020

DOJ’s Prosecution of Generic Drug Companies Continues as it Announces Price-Fixing Charges Against Glenmark Pharmaceuticals, Inc.

July 2, 2020

DOJ and FTC Issue New Vertical Merger Guidelines

July 1, 2020

Germany’s Federal Cartel Office Calls for the EU Court of Justice’s Guidance on Important Patent Licensing Issues

June 25, 2020

Germany’s Supreme Court Sides with National Antitrust Enforcer in Facebook Abuse of Dominance Case

June 23, 2020

Law360: Chilling Tech M&A Could Hurt Competition

June 23, 2020

May Price Gouging Update

June 4, 2020

Updates on Recent US Merger Control Developments - May 2020

May 22, 2020

New Proposed Legislation in California Increases Antitrust Scrutiny in M&A and Other Activities in the Healthcare Industry

May 19, 2020

The Deal: M&A No Special Antitrust Concern During Downturns

May 13, 2020

COVID-19 Antitrust M&A Considerations

May 7, 2020

Collusion in the Healthcare Industry: DOJ Charges Oncology Group for its Participation in a Criminal Antitrust Conspiracy

May 6, 2020

Price Gouging Update—April 2020

April 30, 2020

Gun-Jumping Concerns for Pending Transactions When There Is No Such Thing as “Ordinary Course of Business”

April 27, 2020

The Failing Firm Merger Defense in Times of Economic Turmoil: Past Lessons and the COVID-19 Crisis

April 23, 2020

Antitrust Agencies Watch for Labor Market Collusion in the Healthcare Industry

April 20, 2020

DOJ and FTC on Alert for Anticompetitive Conduct in Labor Markets for COVID-19 Essential Workers

April 15, 2020

Nationwide Shortages Open New Frontiers in Fight Against COVID-19-Related Price Gouging

April 14, 2020

Hong Kong Competition Commission Consults on Proposed Commitments Offered by Online Travel Agents to Remove Parity Clauses from Agreements with Accommodation Providers

April 9, 2020

China Adopts Antitrust Enforcement Policy to Fight COVID-19 and Spur Economic Recovery

April 8, 2020

Antitrust Implications of the President’s Invocation of the Defense Production Act

April 2, 2020

Department of Health and Human Services Triggers Price Gouging and Hoarding Provisions of Defense Production Act

April 1, 2020

Hong Kong Competition Commission Issues Statement on the Application of the Competition Rules to Cooperation Agreements Between Companies Responding to the COVID-19 Pandemic

March 30, 2020

Competitor Collaborations and Communications in Time of Crisis: Practical Guidance

March 26, 2020

Antitrust Agencies Provide Guidance for Competitor Collaborations in Healthcare Sector as COVID-19 Outbreak Deepens

March 25, 2020

European Antitrust in the Time of COVID-19

March 25, 2020

In the News

Press Releases