Microsoft is the only cloud provider that operates in China under Chinese law.

Judged as of October 2017. True if, at that time, Microsoft was uniquely positioned as a major foreign/global cloud provider offering public cloud in China in compliance with Chinese law (via 21Vianet), and no other comparable provider did so. The claim is in the context of global hyperscale providers. Mostly true if Microsoft was the first or the main such global provider but another (e.g., AWS via Sinnet/NWCD) also operated there under Chinese law in a more limited or preview form. Mixed if several global providers had comparable operations, so 'only' is clearly overstated but Microsoft's operation is real. Mostly false if the claim ignores comparable operations by other global providers (e.g., AWS China regions generally available by 2017) and Chinese domestic providers, so that it holds only under a narrow reading. False if many cloud providers, including global peers, clearly operated in China under Chinese law in the same way and Microsoft had no distinguishing status, even on a narrow reading.

Set before the research began.

1. E1 Microsoft Again Claims Unique Cloud Status in China; Others Cry Foul. | Fortune Fortune · 23 May 2017

   “But that claim raises eyebrows because Amazon Web Services, the public cloud market leader, also sells cloud services in China. As does IBM.”

2. E2 Microsoft Again Claims Unique Cloud Status in China; Others Cry Foul. | Fortune Fortune · 23 May 2017

   “Just as Azure China is operated by 21Vianet, Amazon’s Beijing region is operated by Sinnet, Leong said via email. “Both meet the regulatory requirements for foreign cloud IaaS providers with services in China,” she noted.”

3. E3 China Weighs Letting US Cloud Providers Operate Their Own Data Centers Data Center Knowledge · 28 March 2019

   “In August 2016, Chinese data center and internet service provider Beijing Sinnet Technology took over from Amazon Web Services the job of operating and providing AWS cloud services hosted in the US tech giant’s first cloud availability region in Mainland China.”

4. E4 Getting Started with AWS Services in AWS China (Beijing) Region and AWS China (Ningxia) Region | Amazon Web Services Amazon Web Services · 23 August 2019

   “The AWS China (Beijing) Region, which was generally available to Chinese customers in 2016, is operated by Beijing Sinnet Technology Co. Ltd. (Sinnet), while the AWS China (Ningxia) Region, which was launched in 2017, is operated by Ningxia Western Cloud Data Technology Co., Ltd. (NWCD).”

AWS's own blog [E4] says its China (Beijing) Region, operated by Sinnet, was generally available to Chinese customers in 2016, and its Ningxia Region, operated by NWCD, launched in 2017. Data Center Knowledge [E3] confirms that Sinnet took over running AWS's Beijing region in August 2016. In May 2017, Fortune [E1, E2] reported that AWS and IBM also sold cloud services in China, and quoted a source, Leong, saying AWS's Sinnet-run Beijing region and 21Vianet-run Azure China both meet the regulatory requirements for foreign cloud IaaS providers with services in China. So by October 2017 at least one comparable global provider was generally available in China under the same local-operator model, and the claim that Microsoft was the "only" one holds only under a narrow reading.