Sounds like Google (Nasdaq: GOOG), the Mountain View, Calif.-based search and advertising giant, is out to acquire another advertising-technology startup. This time it's Admeld, the New York-based provider of software designed to help Web publishers earn more from advertisers. But there are conflicting media reports, all based on unnamed sources, about how far the deal has progressed.

TechCrunch editor Michael Arrington reported Thursday that "multiple sources" had confirmed that Google has bought Admeld for roughly $400 million -- which would represent an admirable return on the $30 million reportedly invested in the startup by Foundry Group, Norwest Venture Partners, Spark Capital, and Time Warner Investments. A report in AdAge backed up TechCrunch's assertion, citing "a source close to the deal."

But The New York Times' Bits Blog said later on Thursday that the deal is still in the discussion stages. Three sources briefed on the talks are saying that nothing has been signed and that the negotiations "could still fall apart," Times reporter Claire Cain Miller wrote.

Google and Admeld aren't talking about the deal, nor would Spark Capital respond on the record to Xconomy's inquiry about the reports.

Admeld's display-ad optimization technology helps Web publishers evaluate the ads available through real-time bidding networks such as Google's DoubleClick Ad Exchange and decide which to display for maximum revenue. Google may want to build the technology into its tools for publishers. But the Admeld acquisition would be large enough that antitrust regulators might want to take a look at the deal first -- just as they did in 2007, when Google acquired DoubleClick.

Admeld is four years old and was co-founded by Brian Adams and Benjamin Barokas, who formerly led engineering and advertising efforts, respectively, at Canadian Internet video provider JumpTV. Admeld's CEO is Michael Barrett, a former executive at Fox Interactive Media who also has sales experience at AOL, Yahoo!, Disney, and Newsweek.

Wade Roush is Xconomy's chief correspondent and editor of Xconomy San Francisco. You can e-mail him at [email protected] or follow him on Twitter at twitter.com/wroush. You can subscribe to his Google Groupand you can follow all Xconomy San Francisco stories at twitter.com/xconomysf.

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