In this Dec 19, 2013 file photo, the Tencent Holdings Ltd. building stands in the Nanshan district in Shenzhen, China. (BRENT LEWIN / BLOOMBERG)

Tencent Holdings Ltd has offered to buy out and take private search engine Sogou Inc in a US$2.1 billion deal, adding to a slew of Chinese mainland technology giants seeking to delist from US bourses.

Sogou said in a statement it was considering the takeover offer, though Tencent already owns about 39.2 percent of Sogou but controls a majority of voting power

Tencent is offering US$9 in cash for each American depositary share it doesn’t already hold in Sogou, backed by fellow internet giant Sohu.com Ltd. That’s a 57 percent premium to the target company’s Friday close. Sohu’s shares gained 40 percent, their most in a decade, while Sogou leapt a record 48 percent in New York.

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Mainland internet companies are exploring listings closer to home after a proposed US bill threatened to force them to delist from New York by imposing stricter disclosure requirements. Online gaming company Changyou.com Ltd got taken private this year by Sohu, and 58.com Inc is being bought out by a private equity consortium for US$8.7 billion.

Sogou said in a statement it was considering the takeover offer, though Tencent already owns about 39.2 percent of Sogou but controls a majority of voting power. 

The search engine -- whose name translates as “search dog” and floated publicly only in 2017 -- was the default in a slew of Tencent products including its marquee social app WeChat and is making a push into artificial intelligence. It remains runner-up however to longstanding desktop search leader Baidu Inc.

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Sogou may explore a listing in the Hong Kong Special Administrative Region in future, on the heels of well-received debuts by the likes of Alibaba Group Holding Ltd and JD.com Inc. It’s become an increasingly attractive route for mainland tech giants such as Jack Ma’s Ant Group, which is speeding toward what could be the market’s biggest float in years.

The “market has been anticipating more companies to pursue secondary listing in Hong Kong,” Jefferies analysts led by Thomas Chong wrote. “We consider there will be more synergies between Sogou and Tencent in search and smart devices in the future.”

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