It's common knowledge for those who are familiar with Chinese tech industry that OPPO, VIVO are originated from a company called BuBuGao(BBK in English) which

It's common knowledge for those who are familiar with Chinese tech industry that OPPO, VIVO are originated from a company called BuBuGao(BBK in English) which is created by a guy name Duan Yongping (https://en.wikipedia.org/wiki/Duan_Yongping https://en.wikipedia.org/wiki/Duan_Yongping). One plus is founded by another guy that BBK invested as a VC.