A ClickZ article named Paid Search Spawns 'Drafting' and 'Hijacking' Strategies discusses the differences of 'drafting' and 'hikacking' tactics and its legal/ethical consequences. The article explains Peter Hershberg's, from Reprise Media, definition of the two. He defines hijacking "as when a competitor outranks an advertiser's campaign by outbidding them." And drafting he defines "as a case where an advertiser conducts a search marketing campaign and a competitor takes advantage of the traffic by bidding on related terms." The article gets into the ethics of using these tactics, I know I have seen discussion in the SEM world of people bidding on other people's names and most did not appreciate it (see past Search Engine Watch Thread). But soon after the "Mazda Taps Into Pontiac TV & Search Ads Again" topic, Yahoo Banned Bidding On Competitor Trademarks. For more on this, read the ClickZ article.
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