Oak Brook, Illinois--Several potential bidders have approached McDonald's about acquiring a stake in its partner restaurants, including Donato's Pizzeria and the Pret a Manger sandwich chain. The world's largest hamburger chain is considering the sale to a financial partner of a controlling stake of its non-McDonald's chains, which include Boston Market and Chipotle Mexican Grill. Selling a stake would enable McDonald's to pass management responsibility for the partner brands to a third party while retaining an interest. It might then buy the business back at a later date or help arrange an initial public offering. --FT.com