The fight against a legal settlement that would give Google Inc. the digital rights to millions of copyrighted books is starting to resemble a heavyweight brawl in the library.

Microsoft Corp., Yahoo Inc. and Amazon.com Inc. are joining a coalition that hopes to rally opposition to Google’s digital book ambitions and ultimately persuade a federal judge to block or revise the Internet search leader’s plans.

The group, to be called the Open Book Alliance, is being put together by the Internet Archive, a long-time critic of Google’s crusade to make digital copies of as many printed books as possible. A growing number of critics already have filed objections to Google’s book settlement, but none have the clout that the Open Book Alliance figures to wield with three of the world’s best-known technology companies on board.

Peter Brantley, the Internet Archive’s director of access, provided some of the details about the alliance’s members and objectives in an interview. Both Microsoft and Yahoo have confirmed their intention to join the alliance. Amazon declined to comment because the group hasn’t been formally announced yet. The Open Book Alliance also will include an assortment of non-profit groups.

Among other things, the alliance will try to persuade the U.S. Justice Department that Google’s broad settlement with authors and publishers could undermine competition in the digital book market just as more consumers are gravitating toward electronic readers like Amazon.com’s Kindle.

In a bit of irony, the alliance is working closely with Gary Reback, a Silicon Valley lawyer who helped convince the Justice Department to file an antitrust lawsuit against Microsoft that tormented the software maker during the late 1990s.

The Justice Department already is assessing the possible fallout from Google’s book settlement, which is scheduled to be reviewed by U.S. District Judge Denny Chin in an October 7 court hearing in New York.

Microsoft, Yahoo and Amazon all have financial reasons for objecting to the class-action lawsuit settlement that Google reached with authors and publishers 10 months ago. Amazon may have the most at stake, given that it’s a major book seller and is mining the Kindle for even more sales.

Google plans to offer free access to some books through its search engine and sell others as part of a registry that will share revenue with authors and publishers if the class-action settlement is approved.

Opponents of the deal believe it will give Google too much pricing power, and have raised concerns about the company’s ability to stockpile more personal data about the users of its search engines by tracking what they’re reading.

“We see many disadvantages in this settlement,” the Internet Archive’s Brantley said.

Others see tremendous benefits. A wide cross-section of libraries, colleges and authors have endorsed Google’s book settlement.

Google argues that the settlement will be a boon for consumers, who will have easier access to potentially valuable information now gathering dust in remote library shelves. And, Google says, authors and publishers will be able to make more money from out-of-print books.

“The Google Books settlement is injecting more competition into the digital books space, so it’s understandable why our competitors might fight hard to prevent more competition,” Google spokesman Gabriel Stricker said. “That said, it’s ironic that some of these complaints are coming from a company that abandoned its book digitization effort because it lacked ‘commercial intent’”

Stricker was taking a stab at Microsoft, which abandoned its efforts to make digital book copies to focus on more profitable online opportunities.

Microsoft and Yahoo could be hurt if Google’s expanded index of digital books propels even more traffic to its search engine. If that were to happen, Google might process even more search requests than it already does, allowing the company to show more of the text ads alongside search results that generate most of its revenue.

Hoping to siphon advertising away from Google, Microsoft and Yahoo last month announced a planned partnership in search. The proposal, which still must be approved by the Justice Department, calls for Microsoft to run the search engine on Yahoo’s web site in return for 12 per cent of the revenue generated by accompanying ad sales.