Reuters quoted Zhang Mao, head of an antitrust watchdog, as saying that his agency suspects the company of not being fully transparent with information about its Windows and Office sales.

Specifically, the State Administration for Industry and Commerce is concerned about the way basic functions like the Internet Explorer web browser and Windows Media Player are bundled with products like the Office suite.

Microsoft’s three-year battle with the Department of Justice over similar issues, which ended in the company being forced to share its programming interfaces with other companies, had been a landmark in the history of the internet, breaking Microsoft’s hold over the browser market and much else besides.

Although it avoided being fined in the U.S. , it had to pay over $1.5 billion to settle similar charges in the E.U. three years later.

The antitrust probe is one of a flurry against international companies operating in China recently, which has fostered suspicions of a generalized attempt by the authorities to squeeze the profits they generate there. Chinese media argue that foreign companies have been guilty of price-fixing and other tactics of milking the world’s second-largest economy as much as they can.

However, by targeting an issue that already has precedents in the west, the authorities have arguably made it more difficult to argue that the case is politically-motivated.

Zhang said the investigation “is presently ongoing and we will disclose the results to the public in a timely fashion,” according to Reuters. He said the company had promised to cooperate actively with the investigation.

China has already ratcheted up the pressure on Microsoft by banning state procurement of its new Windows 8 operating system, citing security issues.