chinara - 2:46 pm on Sep 28, 2007 (gmt 0) I call that theft. Expanded broad match = click fraud on a massive scale!
For example, Adgroup 1 contains the keyword "cheap widgets" bid at $0.20. Adgroup 2 contains the broadmatch keyword "expensive widgets" bid at $1.00. Expanded mismatch decides that Adgroup 2 should deliver impressions on "cheap widgets" and that the bid for this should be $1.00, so it's okay to charge the advertiser $0.98 for those clicks -- even though the advertiser has specified that they are willing to bid only $0.10 for "cheap widgets".
I call that theft.
Expanded broad match = click fraud on a massive scale!