AMSTERDAM—Shares in ride-sharing and food delivery companies rebounded on Tuesday, ahead of an European Commission proposal expected Dec. 9 that will define when couriers should be considered employees and when they should be considered independent contractors. The Financial Times on Tuesday reported that the proposal, under development for years, will as expected put the burden of proof on companies, rather than workers, to show when their delivery people are self-employed. A spokesperson for the European Commission declined to comment until its publication on Thursday. Shares in the Netherlands’ Just Eat Takeaway.com rose 6.3 percent by 1030 GMT, Germany’s Delivery Hero rose 4.5, and Britain’s Deliveroo was up 1.9 percent, reversing similar declines on Monday, in an apparent relief rally to recover some on Monday’s losses. Uber shares closed at $38.49 in the United States. Analysts for Citi said in a note that Deliveroo is most heavily exposed to the proposed …