Prime members must sign up for the Grubhub service. After one year they will be charged Grubhub’s normal fees unless they deactivate the program. The deal could give Grubhub a much-needed boost. The Chicago-based company was the U.S. market share leader as recently as January 2019, when it controlled 31% of food delivery sales, according to market research firm YipitData. But rivals DoorDash and Uber Eats chipped away at that lead by offering discounted service and rapidly expanding into suburbs. As of May, Grubhub controlled 11% of sales, while DoorDash held 57% and Uber Eats had 31%. Grubhub was hurt by fee caps that dozens of cities put in place to help restaurants during the pandemic. It is also facing lawsuits in Chicago and Massachusetts, where officials have accused the company of deceptive practices, including advertising delivery services for restaurants without their consent. Grubhub has denied the charges. But they have been a headache for Just Eat Takeaway, which announced in April it was considering the partial or full sale of Grubhub. Just Eat Takeaway said Wednesday it continues to explore that sale. In a statement, Grubhub CEO Adam DeWitt said he’s confident the offering will expose many new diners to Grubhub delivery. Grubhub said its research shows that more than half of U.S. adults consider takeout or delivery food “essential,” but only 38% say they use third-party delivery companies. Just Eat Takeaway shares surged 15% on the Amsterdam stock exchange on the news. DoorDash shares fell 7% on the New York Stock Exchange.