Google Launches DoubleClick Ad Exchange

Google is about to launch its most potent weapon to date in the battle over the $15 billion market for display ads—the pictorial banners and videos that support most major Web sites. On Sept. 18 the search giant will launch its new DoubleClick advertising exchange, a sort of stock exchange for online ads it has been developing since early last year.

Google's (GOOG) exchange lets Web sites offer space that ad agencies and online brokers called ad networks can bid for in an automated auction system. Advertisers hope to get a wider choice of ad space and the ability to target ads more precisely to the most likely prospects. Publishers hope to net higher rates than they can from the hundreds of ad networks—which generally pay very low rates—and sell more of the ad space that today goes unsold. As BusinessWeek reported three months ago, Google's ad exchange has been widely anticipated because of the company's growing influence over online ads.