• by Wendy Davis , Staff Writer @wendyndavis, September 10, 2008

Date-stamping glitches on Google News happen occasionally, but this week marked the first time that one moved the market .

United Airlines saw its stock plunge on Monday after a 2002 Chicago Tribune article about a bankruptcy filing got picked up as if it was current. The result was a fast sell-off, followed by a halt in trading. When trading resumed the stock mostly recovered, but the financial consequences to investors who sold early in the day still aren't known.

The Tribune Company says the mix-up was caused after a link to the 6-year-old story got posted on the Sun-Sentinel's Web site as one of the newspaper's most e-mailed stories. The Google News crawler then picked up the 2002 story as if it were current. A researcher from Bloomberg contractor Income Securities News then found the story and posted it to Bloomberg as if it was new.

Long-time Google News users know that these types of mistakes occur occasionally. And experienced researchers usually know how to distinguish between real news of the day and old articles that have mysteriously popped up on the site. Still, the incident illustrates the tremendous power that Google wields these days.

And it couldn't have come at a worse time for Google, which is currently facing pushback on a number of fronts. Privacy advocates complain that the company knows too much about individual users, Viacom is suing for copyright infringement, and Microsoft and marketers are pushing the Justice Department to derail Google's search deal with Yahoo on antitrust grounds. While it doesn't seem fair to blame Google for the United Airlines sell-off this week, it wouldn't be surprising to see the incident used as proof that Google's influence has already grown too strong.