In a speech before the Association of American Publishers (AAP) in New York Tuesday, Thomas Rubin, a Microsoft associate general counsel, argued that while his company's Live Search Books project honors copyright protection, Google's Book Search does not.

"In essence, Google is saying to you and to other copyright owners: 'Trust us -- you're protected. We'll keep the digital copies secure, we'll only show snippets, we won't harm you, we'll promote you,' " said Rubin. "But Google's track record of protecting copyrights in other parts of its business is weak at best."

As an example, Rubin cited a February dust-up between several media firms and Google that was based on a lawsuit filed in 2005 against two Missouri men and the four Web sites they operated -- including EasyDownloadCenter.com and TheDownloadPlace.com. The sites allegedly sold software to search for and then download pirated movies and software from peer-to-peer networks.

"Google encouraged the use of keywords and advertising text referring to illegal copies of music and movies. These actions bolstered Web sites dedicated to piracy and reportedly netted Google around US$800,000 in advertising revenues from just four such pirate sites," Rubin said. "These are not the actions of a company that has the interests of copyright owners as one of its priorities."

The Wall Street Journal first reported on the dispute, which surfaced after the newspaper obtained information on sworn statements made by the two defendants late last year that Google's ad salespeople sold ads to the sites despite being aware of their business practices.