Simpson Thacher & Bartlett and Skadden, Arps, Slate, Meagher & Flom have the lead roles in Chinese e-commerce giant Alibaba Group Holding Ltd.’s $1.22 billion investment, with a private equity fund led by Alibaba chairman Jack Ma, in online video company Youku Tudou Inc.

Hangzhou-based Alibaba and Ma’s Yunfeng Capital will pay a 26.3 percent premium for a joint 18.5 percent stake in Nasdaq-listed Youku Tudou, the result of a $1.1 billion merger between Chinese YouTube-like video sites Youku and Tudou in 2012.