We just set up a campaign for a client in a competitive space, and saw a pattern that looked like click fraud--which we easily could have missed. As part of our management, we tweaked the existing campaign that the client (with assistance from the Google AdWords team) had set up. Fairly complex campaign, with lots of ads, lots of keywords targeted by a bunch of ad groups. Looking back over the first few days, we were pleased to see that the clickthru rate had gone up...way up. To 10.6%, from just over .1%. A little too good, maybe...like twice what we might hope for.

By digging into the specifics, we found that two ads, in totally different campaigns but with the same keyword phrase as a target, had CTRs of 70.2% and 30.6%. What this means is that a competitor, or prankster with nothing better to do, is sitting there all day, clicking on our ad--and rolling up the charges, at over $3 per click. Not only that, but because we set a daily limit, our ad disappears--the real reason a competitor would do this.

Fortunately, Google is very aggressive about pursuing click fraud. For another client, they saw a suspicious pattern and notified us, providing a refund. In this case, we were on top of the specifics, and have reported the abuse. For larger clients where we are managing a PPC campaign with access to conversion rates, we have triggers in the software to alert us to problems. For clients doing PPC themselves, or for small campaigns where it's all tedious, manual management, this is just a reminder to audit what's happening from time to time.

Posted by John Rasco on December 11, 2004
http://refreshweb.typepad.com/refreshweblog/2004/12/check_for_click.html