WeChat, the largest SNS in China, has swept away a total of a half-billion posting for their uncertainty.
South China Morning Post: WeChat has blocked 500 million postings in fight against fake news
WeChat is said to have one billion users. Thus, its magnitude matches Facebook and Twitter. On the other hand, its policy includes the deletion of fraud or doubtful posting. As a result, in this time, massive comments were eliminated.
According to the article above, the regulation of WeChat is very strict, or rather biased. For example, posting mentioning missing Malaysia Airline Flight 370, as well as a cure for cancer, is subjected to censoring because it violates the rule of "rumor."
Indeed, there are several words which are likely to be used in fraud. But there are enormous terms for such purposes, such as "free," "conspiracy," and even "request." Modern spam filters are sophisticated to distinguish junk emails from many postings. Compared to them, WeChat's rule seems inferior in the specificity.
Furthermore, it is extremely difficult to identify a particular post as fake news. It is possible that comments which had been deemed doubtful were proven to be true later. If so, a fake new filter can inhibit the spread of correct information. AI will provide a better solution with good velocity in filtering, but it will not be perfect.
Fake filters are beneficial in the short term but may be disadvantageous in a longitudinal way. I think this kind of filters should be adopted only in an emergency such as after a disaster.