Subject: ROBOTS meta tag and transient information
Tue, 26 Oct 2004 01:14:56 +0000
Subject: ROBOTS meta tag and transient information. To: email@example.com
I run a couple of Wiki sites which are regularly crawled by Google: ww.cliki.net and alu.cliki.net. They feature highly in relevant searches and overall I'm pretty happy with this state of affairs.
You're no doubt aware that the less ethical of the "search engine optimisation experts" spam their URLs onto pages of unrelated but high-PageRanked wiki sites in the hope that the Google bot will index and follow the links to their sites before the wiki's regular users spot and revert the changes. Some people think it's the next big thing after blog comment spam.
So, I would like to minimise use of my wikis as unwitting link farms for spammers. One approach I'm considering is to insert a
<meta name="ROBOTS" content="NOFOLLOW">
html head element when I serve new versions of pages. In 24 hours it's pretty much a given that someone will have noticed and reverted the spam: result, the google karma does not spread to these undeserving cases. Once a page has lasted 24 hours without subsequent edits, I'll stop sending out the meta tag and Google can index the page as normal thereafter.
The downside: this will be less than ideal if the google bot caches meta tags between one run and the next; i.e. if having once seen that it shouldn't follow links from www.cliki.net/index, it remembers that and never follows them again despite that on its next visit the header is no longer there.
So, at last, my question: does your bot cache robots meta tags between runs, and if so for how long and is there any way that a web site can ask it not to? If it doesn't, it seems that this would be a reasonable approach for a lot of wiki engines to help reduce one source of pagerank spam - and when spammers realise this is happening, they'll (eventually, maybe) stop spamming the said wikis. With luck and a following wind, everyone wins.
Let's see if we get a reply ...