Yahoo, historically, has always been perceived as a company that took click fraud seriously. In fact, they launched the Traffic Quality Center in 2007 to make that statement. In addition, we have seen examples of Yahoo refunding money to advertisers time and time again, without the advertiser even requesting the refund. In the past, there were times where Yahoo wasn't all that good at admitting to click fraud, but they made up for it.
Now, we are receiving a report from an old time member at WebmasterWorld that Yahoo is getting very stingy on the click fraud refunds. This advertiser said that in the past month, Yahoo has rejected not one, but two click fraud requests. The advertiser details the issue, after explaining that Yahoo has always granted his click fraud requests in the past:
Much of these clicks reside from countries outside the areas for which I'm targeting. Receiving 500 clicks from Iran in a week (when I receive only 1000 from the United States) sends up flags. Especially considering I have blocked every continent except North America. A .info domain that was registered two weeks ago was somehow able to send more traffic to me than Yahoo.com has all month.
Now, I do not know the details of his click fraud reports. I am sure Yahoo has their side. So I guess, if I hear any updates on this thread, I will let you know.
Forum discussion at WebmasterWorld.