A poster to a DigitalPoint thread suggested that content theft might be the culprit if you see your site dip for a keyword in Google and then not recover. Put the URL on your site that targets that keyword into Copyscape, and it will return a list of potential matches. You can use the free service to check for 10 copies per month; the premium service costs five cents a search, but allows you to perform unlimited searches. It also helps you track cases of plagiarism. Copyscape also offers a Copysentry service that provides automatic monitoring of your content for a fee, with weekly or daily checks of pages depending on the level of monitoring you choose.
If you already use Google Alerts, you know how convenient it can be to have items of interest mailed to your inbox. Why not put those alerts to work to help to catch content thieves? An original writer creating unique content is all but building a fingerprint; you can make use of that by having Google Alerts watch for a phrase that will stand out as being specifically from the item you’re trying to protect. You only need to wait for Google to email the suspects to you – which it will, every day. Bailey recommends this approach for important and/or static pages on your web site.
Mahalo boasts an immensely cool page on Plagiarism (Literary). On the right-hand side of the page, in a Guide Note, you'll find a link to their Plagiarism Detection Tool. It’s a JavaScript bookmarklet, and they include the script. When you add this applet to your browser’s toolbar, you can highlight some text on a page, click a button and watch Google turn up results that contain that text.
Another poster to the DigitalPoint thread I mentioned earlier offers an interesting suggestion to help you detect content theft. He said he tried for months to stop his content from being stolen automatically. Then he starting planting a link to his site in the middle of his articles, “and then a few months later I could tell exactly who had been stealing my articles.” It must have been a simple matter to track the links back and then ban the appropriate IP addresses.
Once you’ve spotted the stolen content, you might want to preserve a snapshot or archive of the page before you take any further action. This is to protect you in case the owner changes the site and disputes your claim. You can do this yourself, but it’s even better to get a third party to do it. The Internet Archive, which runs the Wayback Machine, is a great resource for this. You might also want to check out Yahoo’s MyWeb, currently in beta.
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