Robert_Charlton - 8:12 am on Jun 18, 2007 (gmt 0)

On one-word searches only, at the moment I'm seeing that an exclusion string (a nonsense term with a minus sign in front of it) included in your search will change the results.

Compare your search for...

keyword

...with this search...

keyword -asdf

This trick was noted during the Florida update, where, as I remember, you needed two negative nonsense words per search word... it was theorized to disable the "filter" that was causing the change. Eventually, Google made changes so that these exclusion strings no longer showed the original results.

Back in 2005, it was discussed with regard to the "sandbox," but you needed 13 of these in order to work. And also in 2005, I noticed that sites that had disappeared because they were related via common inbound sources would come back on searches with the exclusion strings included.

You can try this search of webmasterworld.com to find threads discussing the exclusion strings...

florida update "-asdf" site:webmasterworld [google.com]

It might be helpful to compare notes to see if we can learn anything about the update using exclusion string searches now. Chances are that the exclusion strings will only work for a short while before Google makes a change.

I haven't tried any multi-word searches with the 13 exclusion strings, and there's no reason necessarily to believe that that number applies now.