levo - 8:48 pm on May 8, 2010 (gmt 0)

Can I opt out of interest-based advertising for my site? .. However, you cannot opt out of showing ads to users based on their previous interactions with the advertiser, such as visits to an advertiser's website...

https://www.google.com/adsense/support/bin/answer.py?hl=en&answer=140379