Interesting bit from Weibo's Prospectus:
Risks Relating to Doing Business in China
Regulation and censorship of information disseminated over the internet in China may adversely affect our business and subject us to liability for information displayed on our platform.
The PRC government has adopted regulations governing internet access and the distribution of information over the internet. Under these regulations, internet content providers and internet publishers are prohibited from posting or displaying over the internet content that, among other things, impairs the national dignity of China, is reactionary, obscene, superstitious, fraudulent or defamatory, or otherwise violates PRC laws and regulations. Failure to comply with these requirements may result in the revocation of licenses to provide internet content and other licenses and the closure of the concerned websites. The website operator may also be held liable for such censored information displayed on or linked to the website.
In addition, the MIIT has published regulations that subject website operators to potential liability for content displayed on their websites and for the actions of users and others using their systems, including liability for violations of PRC laws prohibiting the dissemination of content deemed to be socially destabilizing. The Ministry of Public Security has the authority to order any local internet service provider to block any internet website at its sole discretion. From time to time, the Ministry of Public Security has stopped the dissemination over the internet of information which it believes to be socially destabilizing. The State Administration for the Protection of State Secrets is also authorized to block any website it deems to be leaking state secrets or failing to meet the relevant regulations relating to the protection of state secrets in the dissemination of online information.
Although we attempt to monitor the content posted by users on our platform, we are not able to effectively control or restrict content (including comments as well as pictures, videos and other multimedia content) generated or placed on our platform by our users. In March 2012, we had to disable the Comment feature on our platform for three days to clean up feeds related to certain rumors. To the extent that PRC regulatory authorities find any content displayed on our platform objectionable, they may require us to limit or eliminate the dissemination of such information on our platform. Failure to do so may subject us to liabilities and penalties and may even result in the temporary blockage or complete shutdown of our online operations.
In addition, the Judicial Interpretation on the Application of Law in Trial of Online Defamation and Other Online Crimes jointly promulgated by the Supreme People’s Court and Supreme People’s Procuratorate, which became effective on September 10, 2013, imposes up to a three-year prison sentence on internet users who fabricate or knowingly share defamatory false information online. The implementation of this newly promulgated judicial interpretation may have a significant and adverse effect on the traffic of our platform and discourage the creation of user generated content, which in turn may impact the results of our operations and ultimately the trading price of our ADSs.
Although our active user base has increased over the past several years, regulation and censorship of information disseminated over the internet in China may adversely affect our user experience and reduce users’ engagement and activities on our platform as well as adversely affect our ability to attract new users to our platform. Any and all of these adverse impacts may ultimately materially and adversely affect our business and results of operations.