Oct. 25 (Bloomberg) -- Google Inc., the world's most-used search engine, is testing a service that may let users sell products online, posing a threat to EBay Inc., the biggest Web-auction company.

Bear Stearns Cos. analyst Robert Peck said today in a note that Google has been testing a Web site that looked like an on online marketplace, similar to that of San Jose, California-based EBay. Peck cited screen shots of a product called Google Base that were posted on a Web log.

``We are testing new ways for content owners to easily send their content to Google,'' company spokeswoman Eileen Rodriguez said today in an e-mail statement. ``We're continually exploring new opportunities to expand our offerings.''

The test signals Google's intention to expand further beyond Web search. Adding online auctions or sales would give Mountain View, California-based Google another way to tap its base of 400 million monthly users for revenue. Chief Executive Officer Eric Schmidt said in June that Google was developing a payment service. EBay's PayPal is currently the most-used Internet payment system.

EBay shares fell $1.54 to $37.88 at 3:26 p.m. in Nasdaq Stock Market composite trading. They fell 32 percent this year before today. Google shares fell $2.23 to $346.42, after rising 81 percent this year before today.

To contact the reporter on this story: Jonathan Thaw in Los Angeles at jthaw@bloomberg.net

Last Updated: October 25, 2005 15:45 EDT