• by Wendy Davis  @wendyndavis, February 7, 2006

Google has been trying to lure big brand marketers to paid search for a while now, but that didn't save car manufacturer BMW from having its German site, BMW.de, expelled from Google's organic results listings for using so-called black hat optimization techniques.

BMW Germany's offense? It apparently showed one page--a "doorway"--to Google's search crawler, but another to visitors. The doorway was allegedly loaded with the keywords "used cars," but the company then redirected visitors to a different landing page.

Google blogger Matt Cutts first wrote about the development this weekend, saying that the tactic violated Google's quality guidelines, which state that Web sites shouldn't show different pages to search crawlers than to users.

A BMW spokesman told Forbes that the company had not done anything wrong. "We do not understand why Google has decided this," the spokesman was quoted as saying.

Doorways are a fairly common type of Web spam tactic--"black hat 101," said Josh Stylman, managing partner of search engine marketing company Reprise Media. "It's a technique that's been frowned upon for years," he said.

BMW is hardly the first big brand Google has expelled, said Stylman, adding that he has come across other companies that were ousted from Google's results pages. "It's entirely possible that some companies go outside the guidelines, and might not even understand what the quality guidelines are."