v. To display a company's ad when a person visits a rival company's website.
Known as hijackware, Gator software positions your banner ads directly against your rival's site. In the States, found that every time a surfer searched its site for a bouquet, a ten dollar discount pop-up ad appeared for rivals Same thing has happened to American Airlines, who've been Gatored by Delta."
—Matt Kelly, “Pocket Vault,” The Mirror, August 10, 2001
2001 (earliest)
It's called getting 'Gatored,' after one of the most popular applications underlying it, and some Web sites are out to restrict the practice. But for others it's fast becoming an effective way to feast on competitors in their own front yard.
—Stefanie Olsen, “Web sites prey on rivals' stores,” CNET News, August 07, 2001
This word comes from a software program called Gator. It's a browser add-on that (among other things) monitors the sites that a person is visiting. When a particular company's site comes into view, the Gator software pops up a banner ad for a rival company.

Thanks to both Gareth Branwyn and Mark Worden, who slipped this word under my door almost simultaneously.
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