Back in October, we mentioned that weibo rolled out new semi-censorship. Apparently this is not enough. Now weibo has four different ways to censor keywords.

A. Explicit complete censorship

根据相关法律法规和政策，“[the blocked keyword]”搜索结果未予显示。

This translates into:

According to relevant laws, regulations and policies, search results for [the blocked keyword] can not be displayed.

Keyword example: 六四

Note: This is the good old way of censorship since the beginning of weibo.

B. Implicit complete censorship

抱歉，未找到“[the blocked keyword]”相关结果。

This translates into:

Sorry, no relevant results could be found for [the blocked keyword].

Keyword example: 江泽民

Note: This is a brand new form of censorship. Sina weibo used to admit what they censored. Now this message will also be shown to b keywords which actually have no results such as "dsfhadslfhadsljk".

C. Explicit semi-censorship

根据相关法律法规和政策，部分搜索结果未予显示。

This translates into:

According to relevant laws, regulations and policies, some of the search results can not be displayed.

Note: This method is employed around October as mentioned in the blog post.

D. Implicit semi-censorship

When you search for the keywords, only some selected results are returned. With a message at the button, stating

为了提供多样性结果，我们省略了部分相似微博，您可以点击查看全部搜索结果.。

This translates into:

In order to provide a diversity of results, we omitted some similar results. You could click here to view all results.

However, this message is shown to every keyword(except complete censored ones and those actually without any results). So you cannot determine the keyword is semi-censored from this message alone. When you click to view all results, sina weibo will append "&nodup=1" to the end of the search url. Now it will show the exact same message as b. Implicit complete censorship.

抱歉，未找到“[the blocked keyword]”相关结果。

This translates into:

Sorry, no relevant results could be found for [the blocked keyword].

Keyword example: 习近平

Note: This is a brand new way of censorship. It's really interesting to see how keywords are censored. For example, the censorship status of "习近平" went from a->not censored(?)->c->d->c. As I started to write this post, it was d, as I used web-archive to record it. When I'm writing this sentence 28 minutes later, however, it switched back to c. Another keyword "江泽民" went from a->b->a->b and stays at b. Our system could now detect censorship a, b(false positive of "dsfhadslfhadsljk" is inevitable), c. We might update our system to detect d if more keywords are censored this way in a prolonged time. Last but not least, this is merely censorship of searching on weibo. Much emphasis is also put on preventing users from posting sensitive weibo. Some keywords couldn't be posted on weibo in the first place, others will trigger a manual review by censors. Unfortunately, we haven't monitored that kind of censorship yet. But you could visit https://freeweibo.com/en to view recently censored posts on weibo.

Update: Now Sina has the 5th way of censoring keywords-7 day delay, please read Sina Weibo Enacts New "7 Day Delay" Function for Sensitive Terms Following 18th Party Congress for detail.