Uber faces legal challenges in California over its handling of drivers, while its effort to acquire online restaurant food ordering pioneer Grubhub is likely to get mired in an antitrust review if the companies ever reach a deal. Meanwhile, Uber's effort to get into grocery delivery is running into problems before it even starts.

Uber's grocery delivery plans rest on a Latin American startup called Cornershop it agreed to buy control of last fall for $459 million. Uber CEO Dara Khosrowshahi recently told investors he is planning to bring Cornershop to many of the markets where Uber operates, especially in the U.S. But antitrust reviews in Mexico and Chile have delayed consummation of the deal. Meanwhile, even before the deal is completed, grocery chains are resisting efforts by Cornershop to expand into the U.S. on its own, The Information has learned. That raises questions about Uber’s success in using the firm to expand, assuming the deal does close.