This morning’s post in “The Monopoly Problem” considers the nature and scope of cost savings or product improvements that result from mergers; should there be an “efficiency defense” in merger cases? herbhovenkamp.substack.com/p/antitrust-...

Antitrust and Mergers: Efficient Production and Competitive Harm

Should there be an Efficiency “Defense” to Merger Challenges?

herbhovenkamp.substack.com

“The Monopoly Problem” post this morning discusses the relevance of economics to antitrust analysis, including the history of its use, questions about whether it is essential, and the type of economics that the antitrust laws employ. substack.com/home/post/p-...

THE ANTITRUST ALLIANCE WITH ECONOMICS

Is it justified? Is it Too Much?

substack.com

my article on antitrust's "breakup obsession" is coming out in Journal of Corp Law. This dog deserved to die a long time ago. papers.ssrn.com/sol3/papers....

My latest post in “The Monopoly Problem” was motivated by the 9th Circuit’s recent Surgical Instrument decision. It considers the role of behavioral economics and limitations on customer knowledge in identifying the sources of monopoly power. substack.com/home/post/p-...

Behavioral Economics and Antitrust

The Meaning and Limits of the Kodak doctrine

substack.com

AOC recently responded to an Apple price increase announcement by saying it must be broken up. This morning’s “Monopoly Problem” contribution examines the problematic issue of when a monopolist should be broken up because of its antitrust violations. substack.com/home/post/p-...

The Rhetoric and Reality of Antitrust Breakups

Monopoly Breakups Rarely Work, Especially in Digital Markets

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This morning’s “Monopoly Problem” post considers one Supreme Court attempt to simplify merger litigation: the “Philadelphia Bank Presumption” -- a merger creating a firm whose market share exceeds 30% is unlawful. It’s not perfect but has some virtues. substack.com/home/post/p-...

Is Antitrust Merger Analysis Too Compex?, Part II

The Philadelphia Bank Presumption

substack.com

This morning’s “Monopoly Problem” post inquires whether antitrust analysis of mergers has become too complex, considers market concentration as a merger metric, and examines how the Brown Shoe decision used it. substack.com/home/post/p-....

Is Antitrust Merger Analysis Too Complex? Part I

Merger Law has a TMI Problem. Simplifying Rules Essential

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This morning my “The Monopoly Problem” substack posted about a promising new appellate decision on anticompetitive algorithmic pricing. The decision creates a conflict in the federal circuit courts, which may motivate the Supreme Court to review it. substack.com/home/post/p-...

A Promising Decision on Algorithmic Price Fixing

And a Circuit Split; Is Supreme Court Review Likely?

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After my July 29 post on algorithmic price fixing in "The Monopoly Problem" the 3d Circuit issued a very promising decision on pricing software used by Caesar's, Harrah's, Tropicana and other Atlantic City hotel-casinos. I'll post more about it tomorrow. assets.alm.com/01/1b/9c698b...

My morning article in “The Monopoly Problem” examines the messy, unproductive way that the courts have been handling cases that involve algorithmic price fixing. It does not have to be as hard as they make it. substack.com/home/post/p-...

Algorithmic Price Fixing

Antitrust Law’s Agreement Requirement and the Role of Human Actors

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My substack, “the monopoly problem,” just posted a piece on antitrust and vertical integration by ownership or contract – its promises, competitive threats, and how to assess them. substack.com/home/post/p-...

Antitrust and Vertical Integration

Why Do Firms Integrate Vertically, and When Does it Harm Competition?

substack.com

My new piece in Promarket examines the relationship among the proposed American Innovation Choice Online Act (AICOA), revised, antitrust law, and industrial policy. www.promarket.org/2026/07/21/a...

AICOA II Is America’s Reverse Industrial Policy Initiative - ProMarket

The revived American Innovation Choice Online Act singles out a handful of Big Tech giants for unique, antitrust-like restrictions, but without the standard methodological rationale of antitrust analy...

promarket.org

This is why university faculty have been moving away from GOP. The movement has been by GOP

Luke Herrine@lookheron.bsky.social · last mo.

This has actually been studied! www.cambridge.org/core/service...

This morning “The Monopoly Problem” includes a post on yesterday’s Paramount merger decision. Hardly the end of this case, but the state Attorneys General have some reason to be hopeful. substack.com/home/post/p-...

Is the Paramount/Warner Merger in Trouble?

This is not over, but the state AGs have reason to be hopeful.

substack.com

Prominent post-Chicago antitrust economist Steve Salop (G-Town) has performed a great service -- a guide to antitrust and modern economics -- free in .pdf or an inexpensive Amazon Paperback. You dont need much economics in order to read it. econantitrustguide.com

Modern Economic Analysis and Antitrust Law: A Guide

Free to download

econantitrustguide.com

The third of my 3-part discussion of the Robinson-Patman Act in "The Monopoly Problem" considers possibilities for reform. Subscription is free. substack.com/home/post/p-...

Reforming the Robinson-Patman Act

Can it be Fixed, or is Repeal the Best Solution?

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This morning my substack “The Monopoly Problem” posted the second in a series – “How Does the Robinson-Patman Act Work? A third post, in a few days, discusses reform possibilities. herbhovenkamp.substack.com/p/how-does-t...

How Does the Robinson-Patman Act Work?

Part 2 in a series on the Robinson-Patman Act

herbhovenkamp.substack.com

This post in The Monopoly Problem, "The Salesman, the Housewife, and the Campaign Against Low Prices," is part of a 3-part series on the Robinson-Patman Act. Coming next: how the RPA works, and then, whether it can be reformed. substack.com/home/post/p-...

The Salesman, the Housewife, and the Campaign Against Low Prices

A Prehistory of the Robinson-Patman Act

substack.com

My new post in “The Monopoly Problem” frets about Trump v. Slaughter as a threat to FTC independence, and wonders what the Agency will look like now and how it can be fixed. substack.com/home/post/p-...

The Future of a Less Independent Federal Trade Commission

What Trump v. Slaughter Says About Independent Regulatory Agencies

substack.com

I argue in “The Monopoly Problem” that antitrust’s rule of reason is not so open ended that it violates the rule of law, but only if the courts keep it within its intended boundaries. substack.com/home/post/p-...

Does Antitrust’s Rule of Reason Violate the Rule of Law?

Answer: It Depends on What You Expect Antitrust to Accomplish

substack.com

Posting from Scotland, so sorry about the hour. Here I argue in “The Monopoly Problem” that antitrust’s rule of reason is not so open ended that it violates the rule of law, provided that the courts keep it within its intended boundaries. substack.com/@herbhovenkamp

The Monopoly Problem | Substack

Professor, University of Pennsylvania Law School and the Wharton School; frequent contributor on antitrust law and legal and business history.

substack.com

tomorrow (June 30) I will be posting on whether antitrust law's rule of reason violates the rule of law. Subscriptions to my substack, "The Monopoly Problem," are free: substack.com/@herbhovenkamp.

The Monopoly Problem | Substack

Professor, University of Pennsylvania Law School and the Wharton School; frequent contributor on antitrust law and legal and business history.

substack.com

This new post in “The Monopoly Problem” shows that market concentration remains important to antitrust policy, but not as important as hard core structuralists once imagined. Subscribe for free: substack.com/home/post/p-...

How Does Market Concentration Matter for Antitrust Policy?

Concentration is Relevant When it Leads to Higher Prices, Lower Output, or Limits on Quality or Innovation

substack.com

My first of two posts on market concentration and its link to bad results examines how U.S. antitrust policy came to be concerned about it. Subscription is free: substack.com/home/post/p-...

Antitrust and Market Concentration

A preoccupation since the Progressive Era

substack.com

Here is my new paper commemorating the 50th anniversary of Hart-Scott-Rodino (HSR) pre-merger notification, which was intended to be enforcement neutral, and assessing its effectiveness. Comments welcome. papers.ssrn.com/sol3/papers....

although "market failure" is defined so broadly as to be practically useless. Nearly NO markets provide as much of things as someone might want..

Simonetta Vezzoso@wavesblog.eurosky.social · 2mo ago

"The Productive State approach targets the specific domains where markets have demonstrably failed.” The list is pretty long...https://www.dropbox.com/scl/fi/6dxv3a834j8z8j6ylkr69/the-productive-state-a-framework-for-manchesterism.pdf?rlkey=va392880ft6y3d2lgx051mfxk&st=cixfxo4t&dl=0

A post in Jacobin Mag. ask if big tech is facing it's "big tobacco" moment. One impt dif is that Tobacco settled into a rigid lockstep, low innovation oligopoly, while tech remains the fastest growing, competitive, and most innovative part of the economy. jacobin.com/2026/06/big-...

Is Big Tech Facing Its “Big Tobacco Moment”?

Tech giants including Meta, Google, and Apple are facing increasing popular resentment and losing more and more major court battles. Yet their profits and power look about as secure as ever.

jacobin.com

This contribution to “The Monopoly Problem” considers Justice Brandeis’ two important decisions that made him the inventor of Antitrust’s Rule of Reason. Subscribing is free. substack.com/home/post/p-...

Justice Brandeis and Antitrust’s Rule of Reason

Brandeis Wrote Two Rule of Reason Decisions; the Second One is Better But Ignored

substack.com

My new post in “The Monopoly Problem” focuses on most-favored-nation agreements and the relationship among Amazon, its coveted Buy Box, and third-party merchants. Subscribe for free. substack.com/home/post/p-...

Antitrust and Amazon’s Limited Most-Favored-Nation Clauses

How Can Amazon Make Merchants Compete for its Buy Box?

substack.com

Some people do not like a “consumer welfare” standard in antitrust because they associate it with a meaning Robert Bork gave to it in the 1970s that is inconsistent with what the Supreme Court has said. See my post in “The Monopoly Problem.” substack.com/home/post/p-...

Two Theories about Antitrust and Consumer Welfare

Robert Bork vs. the Supreme Court

substack.com