California COMPETE Act adds single-firm monopolization, monopsony bar to Cartwright Act
California's new COMPETE Act writes express state-law prohibitions on single-firm monopolization and monopsonization into the Cartwright Act, giving California a parallel route to federal Sherman Act § 2/§ 3 theory.
California has enacted the Competition and Opportunity in Markets for a Prosperous, Equitable, and Transparent Economy Act, adding to the Cartwright Act express prohibitions on monopolization and monopsonization attributable to a single firm rather than to agreement or monopoly power held through exclusionary conduct. The change matters because California has long been the most active state venue for antitrust private enforcement; a statutory single-firm conduct bar lets plaintiffs plead a theory that, under federal monopolization standards, generally requires proof of exclusionary behavior, monopoly power, and anticompetitive intent.
The reported excerpt states the new provision is limited in some respect, but the truncation does not disclose the scope, the elements of the new offenses, or whether the statute carries its own private right of action or is instead a legislative declaration construing the Cartwright Act. Practitioners should confirm the operative text, effective date, and any carve-outs before advising clients.
For major-firm clients, the immediate question is exposure: dominant buyers facing monopsony allegations in labor, procurement, digital advertising, or platform supply, and dominant sellers facing no-Hub-and-spoke theories reframed under state law. The concrete next step is a California-facing review of distribution, sourcing, and platform agreements, plus tracking early complaints and any judicial construction of the new provision.