How many types of message does the webspam team send to Webmaster Tools?

Matt's answer:

MATT CUTTS: Today’s question comes from Tokyo, Japan. The question is, you’ve been sending various kinds of messages via Webmaster Tools to improve transparency. It’s a good move. How many types of messages do you send, and how do you decide what message you send? Great question. So I can share a little bit of stats. At this point, we do send hundreds of thousands of messages each month. That might sound like a lot, but for example, one search engine named Blekko estimated that a million spam pages are created every hour. So the web is very large, so it shouldn’t be a surprise that some percentage of it is spam. And as a result, we do spend a lot of time finding that spam. And since we automatically send messages and notifications when we find it, there are a lot, hundreds of thousands of notifications that we send out each month. There’s a lot of different categories of spam. They’re covered in our Webmaster Guidelines, everything from cloaking to scraping to sneaky JavaScript redirects, paid links, all sorts of stuff. But all of those boil down to roughly about 10 different messages that we send. So hidden text, keyword stuffing, gibberish, all that would go into one message that we send out. I can share some stats from earlier this year, from January and February. Out of the hundreds of thousands of messages that we sent over that time period, roughly 90% of those were for what we call Black Hat. That’s pure, egregious spam, clear cut, anybody sufficiently tech savvy would probably be able to recognize that it’s spam. It’s the stuff that you think of as traditional junk that you just don’t want to show up in your results because it is very clearly spam. About 4% of the messages were because the content had little or no added value, and so it’s not ranking as highly in our search results. About 3% of the messages that we sent were related to hacking. So hacking is a big attack as far as Black Hats. And even though it’s illegal, there’s a lot of people that do that– trying to promote their pharmacy pills or whatever, that sort of thing. So about 3% of those messages were related to hacking. Something like 2% of the messages that we sent out were related to link buying, and about 1% were related to link selling. So overall between 2% and 3% related to links and link spam overall about buying and selling links. So that gives you a broad idea of the sorts of categories that we send things out for and the rough number of messages that we send out each month.

by Matt Cutts - Google's Head of Search Quality Team

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