When it comes to cheating in the world of PPC, the most readily available example that comes to mind is click fraud. While some advertisers are click frauded by competitors trying to exhaust their advertising budget, others are cheated out of clicks by dishonest affiliates that are trying to inflate their own revenues. In this way, the interests of the advertisers and affiliates are both in sync and at odds with each other: while they're both trying to turn users into traffic for the advertiser, what counts as a conversion for the respective parties isn't always compatible.

Straight forward PPC advertising, however, isn't the only way affiliates and advertisers can come into conflict. Essentially, merchants that run their own affiliate marketing program also have to worry about their affiliates sending middle-manning them on traffic that they might have otherwise not had to pay for. As the PPC Blog explains:

Affiliates in competition with other affiliates, the merchant’s internal marketing department or agency, the affiliate network over merchant terms and of course the paid search system itself. In many ways the merchant, the affiliate and the network have the same goal; to increase visitors or sales to the site, yet each party has their very own self serving objectives which are anything but in unison.
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So, how do affiliates bypass [program] rules, working within the ad platforms own system while keeping under the radar of the merchant, the affiliate network and perhaps an ad agency keeping an eye on the SERPS?

Well, the PPC Blogger sees seven ways in which the the affiliate can middle-man the merchant without necessarily being noticed. Each of these is listed below in bold, with my own comments following.

1) Bidding At Certain Times - That is, when the affiliate program managers aren't likely to be at work to notice.

2) Geo-targeting - Going after areas that the merchants aren't in or dont' target themselves..

3) IP Exclusion - If you have an email from the affiliate program managers, you already have what you need to keep them from seeing your illicit ads.

4) Advert Tricks - Copying the merchant's ads ver batim.

5) Masking Affiliate URLs - Simply making the trail of redirects too difficult to follow.

6) Sending Traffic To A Different Domain - There's two ways this can be done, and they depend on whether the manual review period has already come and gone.

7) Using Broad Match To Bypass Trademarks - Think mixing up keywords that would otherwise form a trademark if they were in the right order.

Now, of course, the original post goes into much more detail of how each of these tactics work, so if you're curious about any of these tactics, make sure to check it out. Keep in mind, however, that if you're one of our own affiliates, we have a very elaborate anti-cheating system, so if you want to see your next pay-out, think twice before trying to pull one of these on us.