McDonald's faces nationwide class action in the U.S., accused of using AI pricing to inflate Big Mac prices

McDonald's faces a proposed nationwide class action lawsuit alleging that its AI pricing system coordinates menu prices across thousands of U.S. locations, causing customers to pay higher prices for items such as the Big Mac and Quarter Pounder. The lawsuit was filed on October 2, 2026, in the U.S. District Court for the Northern District of Illinois, accusing McDonald's of violating Section 1 of the Sherman Antitrust Act. Illinois customer Michael Thomas claims that McDonald's has operated this machine learning system since at least 2019, using aggregated transaction data to generate price recommendations for its nearly 14,000 U.S. restaurants, and argues that sharing these recommendations among independently operated locations constitutes coordinated conduct prohibited by Section 1. McDonald's denies the allegations, stating that franchisees set menu prices themselves and that its AI tool is merely a recommendation system that considers local market conditions, with franchisees retaining final pricing authority. The complaint also alleges that McDonald's monitors locations that deviate from recommended prices and pressures them to use its pricing tool, with Thomas stating that participation became mandatory as of January 2026.