Microsoft and Zoom have said they will not process data requests made by the Hong Kong authorities while they take stock of a new security law.
They follow Facebook, Google, Twitter and the chat app Telegram,which had already announced similar “pauses”in compliance over the past two days.
China passed the law on 30 June, criminalising acts that support independence, making it easier to punish protesters.
Apple says it is “assessing” the rules.
If the tech firms make their non-compliance policies permanent, they could face restrictions or a ban on their services in the semi-autonomous region.
And while Facebook, Google, Twitter and Telegram’s services are blocked in mainland China, the same is not true of Microsoft, Zoom and Apple.
In a related development, TikTok – which is owned by the Chinese firm Bytedance – has said it plans to exit Hong Kong within days.
The business had previouslysaid it would not comply with Chinese government requeststo access TikTok users’ data. It operates a similar service called Douyin in its home market, which could theoretically become a substitute. However, Bytedance has indicated it does not have plans to do so at this time.
Microsoft directly offers its Office 365 work app and LinkedIn social networks to both Hong Kong residents and citizens in mainland China.
But while Office 365 is provided directly by the firm to Hong Kong residents, the service is runby a local firm 21Vianeton the other side of the border, allowing Microsoft to remain one step removed.
In the case of LinkedIn, law enforcement data requests have to go via the US government,although the division says it does sometimes“make an exception in an emergency”.
According to Microsoft’s latest transparency report, it received requests for data linked to 81 accounts from Hong Kong’s government between July and December 2019,and provided “non-content data” in most cases.
“As we would with any new legislation, we are reviewing the new law to understand its implications,” said a spokesman for the American firm.
“In the past, we’ve typically received only a relatively small number of requests from Hong Kong authorities, but we are pausing our responses to these requests as we conduct our review.”