My piece on "Finding Monopoly: Antitrust Market Definition" is in the Sep. 2025 CPI Antitrust Chronicle, part of a symposium on market definition in antitrust. No longer paywalled. papers.ssrn.com/sol3/papers....

Good piece by Antonie, Gonzales & Shao: self-preferencing occurs less on digital markets than in the old economy; consistent with fact that online consumers have lower search costs, and indicates flaws in Biden admin targeting of online markets. www.cornerstone.com/insights/art...

CoStar, 2025 WL 2573045 (9thCir) refused to dismiss a complaint alleging that monopoly power for Sherman Act §2 purposes could be inferred simply from the fact that D persistently charged higher prices than its rivals for years, saying nothing about margins or output restrictions.

Yes, it's a win for Google, but I think a win for U.S. technology and its users as well, as well as appropriate recognition by the court that messing around with market structure in a market as dynamic as this one could spell disaster.

The BrwnShoe factors for antitrust market definition can send judges to insane lengths to twist them. See Harley-Davidson, 2025 WL 2374859 (dissenter would find relevant market by interpreting BShoe's "unique production facilities" factor to mean "American made.").

In Gibson the 9th Cir problematically rejected an antitrust claim that the “hub” in a hub-and-spoke conspiracy provided hoteliers with nonpublic price information and the hoteliers (“spokes”) agreed to “abide by” its pricing algorithm’s recommendations. cdn.ca9.uscourts.gov/datastore/op...

Promarket has published my paper on the Epic Games antitrust suits against Apple and Google Play, and their implications for the government’s own pending lawsuit against Apple, including some observations about market definition and remedies. www.promarket.org/2025/08/12/w...

In Papa John's the court provisionally certified a class action of franchise food employees subject to a no-poach agreement; the court assumed that it was unlawful per se. Papa John's Employee and Franchisee Antitrust Litig., 2025 WL 225564 (WDKy. 8-7-2025).

all true and maybe here too. Do you agree that the chances of SCT review on the market definition issue are extremely slim?

In the Google Play case they court rested on the jury's finding of an "Android-only" relevant market. The earlier case challenging the same conduct by Apple found a market for "mobile game transactions" that included both Android and Apple. Can both of them be correct?

Does AI support anticompetitive leveraging strategies? See Erik Hovenkamp's short and accessible paper: "spread of AI is likely to increase the prevalence and complexity of leveraging strategies in digital markets. This poses a challenge to antitrust." papers.ssrn.com/sol3/papers....

EpicGames decision is a good example of a secondary refusal to deal, which should be treated more like tying rather than refusal to deal, where liability is hard to get. The "tie" is not reachable classically, because there is no agreement; instead, it is created by code.

In Brantmeier v. NCAA, 2025 WL 2108638(MDNC July 29, 2025) the court certified an injunction and a damages class [23(b)(2) & (3)] of collegiate tennis players objecting to an NCAA rule limiting their participation (and compensation) in non-NCAA tennis tournaments and activities.

In Quinton v. Amex, 2025 WL 1994848 (EDNY 7-7-2025) the court admitted testimony that Amex's anti-steering rule was unlawful "cross-subsidization" -- a rare case permitting theory that a pure wealth transfer from poorer to wealthier customers could be an antitrust violation.

My new piece in Network L.Rev. A trivial % of mergers are motivated by price. Nearly all are efforts to improve production by scale or uniting complements. So a merger “efficiency defense” is wrongheaded, and the Supreme Court has not embraced it. www.networklawreview.org/hovenkamp-ef...

Christopher Leslie has published a very interesting article on how antitrust can pursue tacit (implicit) collusion more effectively, especially in concentrated markets. Leslie, Antitrust's Interdependence Paradox, 111 Va. L. Rev. 787 (2025), virginialawreview.org/articles/ant...

An interesting cert. petition in the SAP vs Teradata case asks the Supreme Court to get rid of the per se rule for tying arrangements -- well timed given the status of some big tech cases. SAP SE v. Teradata, 2025 WL 1810683 (2025). The lower court: 124 F.4th 555 (9th Cir 2025)

CoStar v Commercial Real Estate Exchange, 2025 WL 1730370 (9c 6-23-2025) sustained a rule of reason claim that the defendant unlawfully made its commercial real estate brokers sign exclusive agreements. Can someone monopolize real estate by monopolizing its brokers?

In a piece in the Regulatory Review this morning Melissa Bredbenner and urge the new administration not to abandon the Biden administration's antitrust concerns about labor. www.theregreview.org/2025/06/23/b...

My “Antitrust and e-Markets” is coming out in Stan. L. & Pol’y Review. Segregating e-commerce, as courts often do, exaggerates digital market power, especially for the many products that are sold both off- and online where e-Markets reduce concentration. papers.ssrn.com/sol3/papers....

In fact, Rehnquist wrote a concurrence in Reiter, predicting the decision would "add a substantial volume of litigation to the already strained dockets of the federal courts, and could be used to exact unfair settlements from retail businesses."

The SCT's first use of "consumer welfare" was in a case (Reiter v. Sonotone, 442US330) that made antitrust damages actions available to consumers. The result was a massive increase in consumer plaintiff jury trials. What this document say makes no sense and, in any event, contains no support.

In case you are in town, I'll be speaking about "Tech Monopolies" in Amsterdam June 3. alti.amsterdam/event/herber...

My piece on the future of Antitrust Populism is out, at 77 Fla. L. Rev. 417 (2025). While neo-Bs took a major hit in the Nov. 2024 election, its future is promising. SSRN version is here: papers.ssrn.com/sol3/papers.....

I’ll be giving a talk on Tech Monopoly in Amsterdam, June 3, 2025. Substantially on how competition law liability standards relate to optimal remedies. alti.amsterdam/event/herber...

But not under U.S. antitrust law; the same opinion found that Apple's existing policies were protected by concerns for product quality and safety and that there were no less restrictive alternatives. Condemnation came from a California non-antitrust provision that did not assess those requirements.

It certainly has personal jurisdiction over them, but legislative jurisdiction requires it to be able to regulate conduct over as wide a range as the injunction prescribes -- and this in conflict with federal law.

The insubordination issue deserves treatment, but the merits are something else. This is California law setting a standard, apparently for the entire country or even the world, and in conflict with the federal antitrust standard. I'm not sure how that survives an appeal.

E.g, the European DMA does not apply in the U.S. But does California law -- in conflict with U.S. antitrust -- apply in New York? in Germany? The Cal. provision gave little weight to Apple's quality/protection defenses, which have been decisive in federal cases.

Yes, Now the hard part. The 9th Cir. had found no federal violation but did under Cal. state law; the injunction states no territorial limit. This is significantly broader than courts issuing nationwide injunctions for violations of federal law. Can California apply its law to the world?

Promarket posted my piece on the court's use of the per se tying rule in the Google Ad Tech case -- unnecessary to the outcome and perpetuates too much bad law. www.promarket.org/2025/04/29/g...

A judge sustained a complaint that Burger King and its franchisees conspired to restrict employee movement among franchisees. If the franchisees themselves conspired this is a no-poach, not a noncompete; perhaps illegal per se. 2025-04-09 Order - Arrington v Burger King.pdf.

Why do many assume that an output standard for antitrust benefits only consumers? it benefits workers too. Wages are variable costs; the # of jobs varies with output. By ignoring this neo-B’s narrow antitrust labor protection to restraints that explicitly occur in labor markets.

Got an unexpected SCT cite yesterday in a case about medical marijuana, which I know nothing about. J. Barrett wrote an interesting analysis comparing injury requirements under RICO (at issue) with those under antitrust law. Med. Marijuana v. Horn, 2025 WL 978102 (Apr 2, 2025)

My new piece on Network Law Review considers why antitrust law has adopted its particular analytic tools, Justice Brandeis’ influential role as a pioneer in antitrust forensic evidence, and whether economics has made antitrust more conservative. www.networklawreview.org/forensic-too...

Interesting decision in Gamboa v. Apple, holding that fact that iPhone works better with Apple's own cloud storage than with rivals' is a unilateral design feature, not a tying agreement. 2025 WL 660190 (N.D.Cal. Feb. 28, 2025).

very accessible summary article by Nate Miller on growing market power, finding that in many industries margins have been increasing but costs have been falling. Thus sometimes increasing power but decreasing prices. Further, it's very industry specific. www.networklawreview.org/rising-marke...

In Key v. Qualcomm’s 9Cir upheld “no license, no chips” policy: Q won’t sell modem chips unless you take Q’s patents; previously (969 F3d 999) court held that practices were lawful because they only hurt customers, not competitors. Consumer Welfare upside down. 2025 WL 597604.

Interesting decision in Express Scripts, 2025 WL 486195 (WDWa.2-13-2025) that a group of Pharmacy Benefits Managers with 80% of USA prescriptions are not engaged in “joint purchasing” unless they are actually integrating their operations. Otherwise it’s just a cartel.

Unlike the Tapestry case last year, a court refused to find a relevant market for "premium" mattresses, relying on both Brown Shoe factors and hypothetical monopolist test. FTC v. Tempur Sealy, 2025 WL 384493

Unlike the Tapestry case last year, a court refused to find a relevant market for "premium" mattresses, relying on both Brown Shoe factors and hypothetical monopolist test. FTC v. Tempur Sealy, 2025 WL 384493

I am just now in the process of writing the 7-year revision of the Antitrust Law volume on the Robinson-Patman Act -- once again reminded of the shocking business and economic ignorance that law displays.

This paper considers how adoption of a “consumer welfare” standard changed antitrust analysis or enforcement. It considers critiques and defenses of the standard as well as notable “outliers.” Comments welcome. papers.ssrn.com/sol3/papers....

I don't think the food desert story is covered by the RPA because the premise is that the "stranded" store is the only one available to a certain set of customers. The high and low priced stores must actually be in competition with each other.

Even the Robinson-Patman Act acknowledges that a simple refusal to sell is Okay: "...nothing herein contained shall prevent persons ... from selecting their own customers." 15 USC 13(a). As a result, courts hold that one can comply with the Act by simply not selling at all to smaller dealers.

It's a strong complaint -- not only allegations of hub-and-spoke style output reduction efforts, but also direct communication among landlords.

Many mergers are formally of "competitors" but incorporate numerous complements (e.g., connecting routes in airlines). For these relationships: 1) HHI is practically worthless and 2) the expected result with respect to the complements is higher output, lower prices, or better products/services.

Tentatively the 2023 MG standards of HHI>1800 and ΔHHI>100 seem as well as we can do for a general standard, altho ΔHHI>100 may be a bit too aggressive. Even so, there is unacceptably high heterogeneity in the results. The main reason, I believe, is underestimation of complementary relationships.

eg, Bhattachara, et al (2023). Even in concentrated markets (HHI>2000), 25% yield lower prices, 25% higher ones, and 50% no real change. In this concentration range, supports inference that roughly 75% produce cost reductions sufficient to reverse price effects. papers.ssrn.com/sol3/papers....