One source said the float could take place as soon as this year. Best and the banks declined to comment. Alibaba Group Holding Ltd, Best's biggest shareholder, has endorsed the listing plan and would also consider investing in the float, said one of the people. The e-commerce giant, which in June increased its stake in Best to 33% via a $150 million convertible bond, also declined to comment. Alibaba's interest in the float would mark another effort to gain more say in the world's biggest logistics market which is rapidly growing but remains highly fragmented. Alibaba also has stakes in four other Chinese couriers - STO Express Co Ltd, YTO Express Group Co Ltd, ZTO Express (Cayman) Inc and Yunda Holding Co Ltd.