by Stephen Shankland
May 8, 2008 12:52 PM PDT

MOUNTAIN VIEW, Calif.--Google's top executives on Thursday gave a glimpse into how it might try to deflect antitrust concerns of a possible ad-sharing deal with rival Yahoo, advising observers to look at the overall ad market. "You are narrowly focused on search advertising," co-founder Sergey Brin told reporters at the company's headquarters here before Google's shareholder meeting.

"Advertising as a whole is much broader, and Internet advertising is much broader." The observation has bearing on the issue of whether Google has a monopoly and whether a deal with a rival would therefore reduce competition. "Advertisers always have multiple choices. It makes sense (for advertisers) to always use more than one," Chief Executive Eric Schmidt added. "It's incorrect to assert there's lock-in or opportunity for dominance in the ad space. Don't map (computer) platform economics to ad economics."

Schmidt wouldn't comment on whether a deal was imminent, but one source familiar with the situation expects an announcement next week. Co-founder Larry Page also specifically said Yahoo is "strong" in the display ad market. Google's cash comes chiefly from text ads in the form of AdWords, which appear alongside search results, and AdSense, which appear on partners' Web pages; its acquisition of DoubleClick, though, is designed to improve its display-ad business.

When Yahoo and Google announced a two-week test under which Yahoo showed a limited number of Google text ads alongside search results, Microsoft raised antitrust concerns. The partnership also was a major factor in Microsoft's displeasure with Yahoo acquisition talks. Yahoo-Google ad test a success - The two-week test with Yahoo went well, Brin said.