Chen Feng, chairman of HNA Group

From a Buddha-shaped building on the tourist island of Hainan, HNA Group has transformed itself into one of China's most aggressive dealmakers — and drawn scrutiny of its ownership and financing. Founded as a provincial airline by economic reformers who drew on World Bank support, the parent of Hainan Airlines has grown into a sprawling, privately held international conglomerate.

To fuel its growth, it has leveraged existing assets to fund the purchase of new ones — a process known in Chinese as "a snake swallowing an elephant".