Chinese officials are subjecting United States technology companies to so-called security reviews.
Other companies that may have been secretly interrogated include Microsoft (msft) and Cisco (csco), the Times suggests. The paper alludes to a 2014 story in the state-sponsored newspaper China Daily (likely this one) that also names Yahoo (yhoo), Google (goog), and Facebook (fb); however, they do not operate in the country.
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The reviews apparently focus on aspects of these companies' products and technology—such as data storage and encryption—and whether they might endanger China's national security. Chinese officials conduct these reviews in person, the Times reports.
Few other details about the nature of the program have surfaced, though tantalizing tidbits do occasionally pop up in local Chinese media outlets before. For instance, this 2015 report in The Beijing News suggests Apple's security reviews in China commenced at the beginning of last year.
The Cyberspace Administration of China, the bureau that apparently carries out the reviews, told the Times that, as the paper paraphrases, "many countries carried out security reviews and that the inspections did not target any particular country or product." Unlike tech reviews in countries such as the U.S. and Great Britain, the ones in China do not appear to limit themselves solely to military and government technology. China inspects consumer gadgets too.
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Apple's general counsel Bruce Sewell told the U.S. Congress last month that the Chinese government had requested access to the company's source code, which the company denied.
The purported aim of the reviews includes preventing tech firms from aiding foreign government spying or otherwise exploiting people's information. Some fear that the reviews could give China leverage to steal tech from these companies, allowing the country to build more products at home, or to provide the country's hackers with knowledge about breaking into U.S. systems.
Apple, Cisco, and Microsoft did not immediately reply to Fortune's request for comment.