Trademark poaching refers to the affiliate’s practice of using registered trademarks as keywords for bidding on search engine PPC platforms (i.e., Google AdWords). More rarely, the term may be used for referring to trademark keyword buying made by competitors. This affiliates’ practise is considered as poaching when it is forbidden by terms and conditions of the affiliate agreement.
Through trademark poaching, the unscrupulous affiliates "steal" an organic traffic which will otherwise go directly towards the merchant which own the affiliate program. By bidding on merchants’ trademarks or domain names, poachers sets an affiliate cookie on the end user’s machine and when the latter place a sale the affiliate will earn the commission based on that sale.
The practice is usually very profitable because bids are low (few bidders takes the risk to bid on registered trademarks) and conversions are good (from start the user want access the merchant website and probably with an order intent).
The vast majority of merchants forbids the use of their trademarks or URLs as keywords by their affiliates, considering that is paying for orders or leads that they would have had freely.
When poaching, affiliate generally do not use a direct link to the merchant in their PPC ads, since it would show a referring URL from a search engine page with the associated keyword.
Poachers use a range of practices to prevent detection from merchant and affiliate network side.
Many techniques and services may be used for trademark poaching detection.
Usage of trademarks by affiliate keyworders according to The Search Monitor: