DoorDash Inc. and Grubhub Inc. are challenging a San Francisco ordinance permanently capping the fees delivery companies can charge restaurants, claiming the city is retaliating for the industry’s support of a ballot measure exempting delivery companies from a state law that would have forced them to treat drivers as employees.

In June, San Francisco became the first city to permanently limit the amount third-party delivery companies can charge restaurants to 15% per order. The city initially enacted the policy as a temporary measure in December to protect struggling restaurants during the COVID-19 pandemic.