Share on LinkedInShare on LinkedIn

ARTICLE · 12 FEBRUARY 2024

Developments In U.S. Antitrust Litigation — 2023 Year In Review

Arnold & Porter
Arnold & Porter
Contributor
Arnold & Porter

Arnold & Porter

With over 1,000 lawyers across 16 offices worldwide, Arnold & Porter is renowned for its...

View firm profile
Explore more from Arnold & Porter

2023 was an eventful year for antitrust litigation, with 250 new antitrust complaints filed.

United StatesAntitrust/Competition Law
Daniel B. Asimow
Daniel B. Asimow
C. Scott Lent
C. Scott Lent
Sonia Kuester Pfaffenroth
Sonia Kuester Pfaffenroth
Laura Shores
Laura Shores
Matthew Tabas
Matthew Tabas
Patrick Shaw
Patrick Shaw
Author LinkedIn connections

2023 was an eventful year for antitrust litigation, with 250 new antitrust complaints filed. The U.S. District Court for the Northern District of California continued to be the most popular jurisdiction for antitrust plaintiffs, with 42 cases filed in 2023. Northern California was followed by the District of New Jersey, with 30 cases; the Northern District of Illinois, with 19 cases; and the Southern District of New York, with 16 cases.

Both the antitrust authorities and private plaintiffs were focused on aggressive enforcement and sought to apply the antitrust laws to new technologies and existing theories of harm in new ways. Indeed, plaintiffs targeted a wide range of industries with antitrust actions in 2023, from tech to real estate and from sports to pharmaceuticals. This trend is unlikely to slow down in 2024.

We operate a free-to-view policy, asking only that you register in order to read all of our content. Please login or register to view the rest of this article.

Register for freeORLog in

The content of this article is intended to provide a general guide to the subject matter. Specialist advice should be sought about your specific circumstances.

View source

Related Articles

Legal Intelligence Newsletters: sign up for the latest legal and regulatory news on your chosen topics

Read more about

Related Comparative Guides

See more popular content from

Article

Booking Holdings v. Commission: General Court Clears The Way For Reverse Leveraging

The General Court of the European Union has upheld the European Commission's prohibition of Booking Holdings' acquisition of eTraveli Group, endorsing for the first time a 'reverse leveraging' theory of harm in conglomerate mergers. This landmark judgment establishes that dominant companies can be blocked from acquiring complementary businesses even when the target operates in a market where the acquirer lacks dominance, fundamentally reshaping merger control enforcement in digital and ecosystem-driven mark
United StatesAntitrust/Competition Law
Baker Botts L.L.P.
Baker Botts L.L.P.
Article

KKR Agrees To Historic $250 Million Penalty For Alleged Violations Of HSR...

The Department of Justice announced a landmark $250 million settlement with KKR & Co. for allegedly submitting deficient Hart-Scott-Rodino Act notification forms across at least 16 transactions. This unprecedented penalty, the largest ever for HSR violations, raises critical questions about merger notification compliance obligations and the consequences of systemic noncompliance with federal antitrust review requirements.
United StatesAntitrust/Competition Law
Bracewell LLP
Bracewell LLP
Article

Recent Significant Federal Merger Enforcement Developments

The Justice Department has resumed targeted Second Request investigations to expedite merger reviews, while major entertainment industry consolidation faces legal challenges and the FTC secures record penalties for Hart-Scott-Rodino Act violations. These developments signal a shifting landscape in federal merger enforcement, balancing efficiency with rigorous antitrust scrutiny across multiple industries.
United StatesAntitrust/Competition Law
Wiggin and Dana LLP
Wiggin and Dana LLP
Article

DOJ Merger Investigation Closure Credits AI Competition And Highlights Targeted Second Request Reviews

The U.S. Department of Justice recently closed its investigation into a merger between two leading sales enablement software providers, citing AI competition as a key protective factor against potential competitive harm. This decision offers important insights into how antitrust agencies are evaluating AI-native companies as competitive constraints and implementing more efficient, targeted merger review processes in technology sector transactions.
United StatesAntitrust/Competition Law
A&O Shearman
A&O Shearman
Article

Pseudonymised, Not Anonymous: What The Italian Garante’s €7 Million IQVIA Fine Means For Health Data

The Italian data protection authority fined IQVIA Solutions Italy €7 million for treating patient records as anonymous when they were actually pseudonymised personal data subject to GDPR. This decision demonstrates regulators' strict interpretation of what constitutes personal data, even as the EU considers narrowing this definition through the Digital Omnibus reforms.
GlobalPrivacy
Arnold & Porter
Arnold & Porter
Article

Generative AI Is Reshaping The Defense Of Complex Litigation

Generative AI is transforming litigation defense by enabling in-house legal teams to manage costs and complexity more effectively across the entire case lifecycle. From early research and drafting through expert witness strategy and trial preparation, AI tools are helping defense teams work faster and more consistently. How are these technologies reshaping the way sophisticated counsel approaches multidistrict litigation, mass torts, and large-scale document management?
United StatesMedia, Telecoms, IT, Entertainment
Arnold & Porter
Arnold & Porter
Article

The FCC’s Next Move On Supply Chain Security: What Manufacturers Need To Know

The Federal Communications Commission has proposed sweeping changes to its equipment authorization program that would reorganize security restrictions around where devices are manufactured rather than who makes them. These new measures could fundamentally reshape how communications equipment—from smartphones to data center hardware—enters the U.S. market, with significant implications for manufacturers relying on foreign production.
United StatesGovernment, Public Sector
Arnold & Porter
Arnold & Porter
Article

District Court Enjoins EPA From Reclassifying California’s Clean Air Act Waivers

A federal district court has preliminarily enjoined the EPA from reclassifying California's Clean Air Act preemption waiver orders as "rules" subject to the Congressional Review Act. The court found that EPA's reclassification likely violated the Administrative Procedure Act and exceeded the agency's authority, though the order does not prevent Congress from proceeding with pending disapproval resolutions.
United StatesEnvironment
Arnold & Porter
Arnold & Porter
Article

China Compliance Update: Anti-Corruption — Summer 2026

Chinese authorities issued the first major update to criminal bribery laws in a decade, lowered thresholds for private-sector corruption crimes, and maintained aggressive enforcement against both bribe givers and receivers. Three senior officials faced prosecution in the first half of 2026, with investigations reaching back decades and emphasizing "family-style corruption" involving relatives who exploited officials' influence for personal gain.
ChinaCriminal Law
Arnold & Porter
Arnold & Porter
Article

Before The FCA: CMS And HHS Leaders Discuss Administrative Tools Leading Healthcare Fraud Enforcement

Federal healthcare fraud enforcement leaders reveal a strategic shift at CMS and HHS-OIG, where administrative sanctions—including enrollment moratoria, revocations, and exclusions—now serve as the first line of defense against fraud, often preceding False Claims Act litigation. The panel discussion at AHLA's Fraud and Compliance Forum outlined how agencies are leveraging data analytics, financial crimes intelligence, and cross-program coordination to identify and shut down fraudulent providers
United StatesFood, Drugs, Healthcare, Life Sciences
Arnold & Porter
Arnold & Porter
Article

Sterling v. City Of Jackson And The Limits Of Substantive Due Process In Environmental Harm Cases

The Fifth Circuit's en banc decision in Sterling v. City of Jackson tests whether residents exposed to lead-contaminated municipal drinking water can sue under Section 1983 for substantive due process violations. In a 10-5 ruling, the court held that environmental harms caused by government mismanagement belong to tort law and the political process, not constitutional claims, creating a significant circuit split with implications for how environmental compliance failures by public officials are litigated.
United StatesLitigation, Mediation & Arbitration
Arnold & Porter
Arnold & Porter
Article

S.D.N.Y. Upholds New York’s Social Media Content Moderation Disclosure Law

A federal court in New York upheld a state law requiring social media platforms to disclose their content moderation policies, applying a deferential First Amendment standard. This decision directly conflicts with a Ninth Circuit ruling on California's similar statute, potentially setting the stage for Supreme Court review on whether such disclosure requirements constitute protected commercial speech or impermissible compelled expression.
United StatesMedia, Telecoms, IT, Entertainment
Arnold & Porter
Arnold & Porter
Article

All Eyes On Personalized Pricing: What Stakeholders Need To Know

The Federal Trade Commission has proposed a new enforcement policy targeting personalized pricing practices, signaling heightened scrutiny of businesses that use consumer data to set individualized prices. As states simultaneously advance their own surveillance pricing legislation—ranging from disclosure mandates to outright bans—companies face an increasingly complex regulatory landscape that demands...
United StatesConsumer Protection
Arnold & Porter
Arnold & Porter