(Yicai Global) Jan. 11 -- Alibaba Group Holding's Chief Marketing Officer Pen Hung Tung has replaced Chairman Daniel Zhang as social media giant Weibo's director amid China's trending anti-monopoly sentiments.

Zhang resigned as Weibo director yesterday, the Beijing-based microblogging platform operator said in a filing with the Hong Kong bourse yesterday, without specifying the reason behind the Alibaba chief's departure. The e-commerce behemoth has a nearly 30 percent stake in the platform.

The Alibaba leader has also left some other duties lately amid China's tightening regulatory environment for big internet companies. Zhang resigned as Didi Global's director, China's biggest ride-hailing platform said in its financial report on Dec. 29. Alibaba's Senior Legal Director Zhang Yi was appointed to the role.

Zhang succeeded Jack Ma after the founder stepped down as the Hangzhou-based firm's executive chairman in September 2019. Before that, Zhang was the Taobao owner's chief executive. He began to serve as Weibo's director in May 2014.

Alibaba holds nearly 30 percent of Weibo's shares indirectly. The shares were worth about HKD17 billion (USD2.2 billion) based on Weibo's market cap of HKD58.8 billion as of Dec. 31, 2021. Weibo finished its secondary listing in Hong Kong last December.

The e-commerce company has been a shareholder for long. Alibaba made a USD586 million investment in Weibo in April 2013, public information shows. It invested another USD449 million after Weibo went public on the New York Stock Exchange in April 2014.

Alibaba is the single biggest advertiser on Weibo, the platform said in its prospectus filed with the HKEX. The pair's cooperation affects the latter's operating performance and development prospects, it added. In the first half of 2021, Alibaba's ads made up 7 percent of Weibo's revenue.

Weibo's shares [HKG: 9898] closed 2.1 percent down at HKD259.60 (USD33.30).

Editor: Emmi Laine, Xiao Yi