McDonald's AI menu pricing antitrust lawsuit (Thomas v. McDonald's USA)

An Illinois customer filed a proposed nationwide class action on October 2, 2026, claiming that McDonald's and its franchisees fix menu prices through a shared, AI-driven pricing tool. The case is Thomas v. McDonald's USA, LLC and McDonald's Corporation, No. 1:26-cv-12149, in the U.S. District Court for the Northern District of Illinois.

The complaint says McDonald's pools nonpublic sales data from franchised and company-owned restaurants, runs it through a "pricing engine" and recommends prices that competing restaurants are pressured to follow. McDonald's publicly denies that AI sets its prices and says franchisees set their own.

The lawsuit seeks to represent people across the United States who bought menu items at McDonald's restaurants, plus an Illinois subclass. No court has ruled on the claims, and no class has been certified.

McDonald's USA, LLC is a Delaware company based in Chicago and a wholly owned subsidiary of McDonald's Corporation, also a Delaware corporation based in Chicago. The complaint says about 95% of the roughly 14,000 U.S. McDonald's restaurants are owned by independent franchisees. It names franchisees and company-run operating units as alleged co-conspirators but does not sue them.

The plaintiff is Michael Thomas of DeKalb, Illinois. The complaint says he regularly buys menu items at several McDonald's restaurants and has paid different prices for the same items at different times.

He is represented by Clarkson Law Firm, P.C., through Derek Y. Brandt in Chicago, with Larkin Turner listed as seeking permission to appear.

According to the complaint, McDonald's bought the AI company Dynamic Yield in 2019 and has since run a centralized machine-learning pricing engine. It says the franchise disclosure document requires restaurants to send transaction-level sales data to McDonald's and lists an annual fee for the "Pricing Engine."

The complaint relies heavily on a Reuters report published September 29, 2026. Citing that reporting, it alleges the tool estimates local customers' willingness to pay, warns restaurants when prices look too low and applies a "30% rule" that ties one restaurant's price increase to whether nearby McDonald's restaurants already raised theirs. It also alleges that since January 2026 franchisees have been required to use the company's approved pricing consultant and tools, and that "pricing non-compliance" can affect franchise renewals and expansions.

The complaint quotes a September 23, 2026 investor presentation describing the engine as providing "pricing recommendations down to the restaurant and item level." It also says McDonald's own May 2024 fact sheet reported average menu prices up about 40% from 2019 to 2024.

On October 1, 2026, the day before the suit, McDonald's published a statement titled "Separating Fact from Fiction: AI Does Not Set Prices at McDonald's."

The plaintiff argues that McDonald's organized an agreement among competing restaurants to fix prices using pooled confidential data, which he says is illegal on its face under antitrust law. He says customers paid higher prices as a result.

The complaint brings four claims: two under Section 1 of the Sherman Act (price fixing and unlawful exchange of competitive information), one under the Illinois Antitrust Act and one under the Illinois Consumer Fraud and Deceptive Business Practices Act.

McDonald's October 1 statement says AI "does not set the price of a Big Mac or any other menu item," that the company "does not use dynamic pricing," and that "franchisees independently set menu prices." It calls the tool's output "a recommendation, not a mandate," and says its franchisee value assessments are "holistic," with price "one consideration among many." The statement was published before the lawsuit and is not a court filing. The docket showed no answer or motion from McDonald's as of October 19, 2026.

The case is assigned to U.S. District Judge Thomas M. Durkin. Public docket summaries show filings on October 8, but their contents were not available.

The court has not decided whether McDonald's and its franchisees agreed to fix prices, whether the tool raised prices or whether a class should be certified.

A separate antitrust complaint, Rossi v. McDonald's Corp., No. 1:26-cv-12651, was filed in the same court on October 15, 2026, and is assigned to Judge Sunil R. Harjani. Class Action Pulse has not reviewed that complaint.

The complaint proposes two groups:

• Nationwide Class: all persons in the United States who bought menu items at McDonald's restaurants, whether run by McDonald's or by a franchisee.
• Illinois Subclass: all Illinois residents who bought menu items at McDonald's restaurants in Illinois.

McDonald's, its affiliates, officers and directors, and the assigned judges are excluded. The complaint does not list fixed start or end dates for the class period, though it describes the alleged conduct as starting no later than 2019. The plaintiff can change the definitions later.

There is no claim form and no deadline. Customers can:

• Save receipts and McDonald's app order history showing items, prices and restaurant locations.
• Watch for any ruling on a motion to dismiss or class certification.
• Contact Clarkson Law Firm or their own lawyer with questions.

There is no money available. The complaint asks for damages trebled under federal antitrust law, enhanced damages under the Illinois laws, restitution, orders ending the alleged agreement and barring similar ones, a court-approved notice program paid by McDonald's, interest and attorneys' fees. These are requests, not awards. Treble damages would apply only to any overcharge proven in court, not to the full price of a meal.

• September 29, 2026: Reuters publishes its report on the pricing tool.
• October 1, 2026: McDonald's publishes its statement.
• October 2, 2026: Thomas complaint filed.
• October 15, 2026: separate Rossi complaint filed.

No claim, opt-out or objection deadlines exist. If a class is certified or a settlement is reached, notice would explain members' options.

• Franchisee: An independent business licensed to run a restaurant under the McDonald's brand.
• Per se violation: Conduct, such as price fixing among competitors, that antitrust law treats as illegal without detailed proof of its effects.
• Information exchange: Competitors sharing nonpublic data like prices or sales, which can raise antitrust concerns.
• Dynamic pricing: Changing prices in real time based on demand or time of day.
• Treble damages: Damages tripled after proof of an antitrust violation.

McDonald's is expected to respond, likely with a motion to dismiss. The court may also be asked to coordinate the Thomas and Rossi cases. Class Action Pulse's news report on the filing has more background.

A practical note: app orders keep a dated record of what you paid at each location, which is often easier to find later than paper receipts.

This article relies on the complaint, the court docket, McDonald's October 1, 2026 statement, the Rossi docket, and Reuters.

The 30% rule, compliance pressure and overcharge claims are allegations, many drawn from news reporting rather than internal documents. The Rossi complaint and the October 8 filings were not reviewed. Class size and any recovery are unknown.

Class Action Pulse is not a law firm or settlement administrator and does not guarantee eligibility or payment. This article is general information, not legal advice.