The Kunlun purchases had never been submitted to Cfius, giving the government the leverage to go back in after the sale to try to force a divestment. Calls to Kunlun’s office number were not answered, and emails seeking comment were not returned.

Grindr has already faced questions about its control and use of personal data. The company faced a huge backlash for sharing users’ H.I.V. status, sexual tastes and other intimate personal details with outside software vendors. After the data sharing was made public by European researchers in 2018, the company said it would stop sharing H.I.V. data with outside companies.

Last year was the first time Cfius appeared to be concerned about the purchase of companies that contained sensitive data. The government killed a proposed merger last year between MoneyGram, the money transfer firm, and Ant Financial, a payments company related to the Chinese e-commerce giant Alibaba.

The United States has also embarked on a global campaign to block a big Chinese telecom equipment giant, Huawei, from building the next generation of wireless networks, known as 5G, over concerns that it could divert critical data through China, or be forced to turn over data running through its networks to Beijing. The White House has essentially accused Huawei of being an arm of the Chinese government that can be used for spying or to sabotage communications networks, a charge that Huawei has vehemently denied.

But the administration’s efforts to control what kind of personal data is available to China’s intelligence services may have come too late. China’s ministry of state security and other Chinese groups have already been accused of successfully stealing personal data from American databases.

The theft of 22 million security clearance files from the Office of Personnel Management in 2014, along with similar theft of data from the Anthem insurance networks and Marriott hotels, have all been attributed to Chinese actors by American intelligence officials, who say they were most likely operating on behalf of the government.

The files stolen in the 2014 government breach contain far more personal data than the Chinese could probably find on any individual social media site: They include work history on sensitive United States projects, information about bankruptcies, medical conditions, relationship histories, and any contacts with foreigners. The loss of the information forced the C.I.A. to reassign personnel headed to China, and was considered among the largest losses of sensitive security information in decades. The Obama administration declined to publicly concede that the breach was committed by Chinese intelligence services.