The Authors Guild suffered a big blow on Wednesday in its battle against the wholesale copying of copyrighted books by Google Inc. and its partners. U.S. District Judge Harold Baer Jr. in Manhattan put a stop to a suit by the Guild and its allies against the HathiTrust Digital Library–a massive digitization project involving Google and more than 60 university libraries–ruling that the defendants’ digital reproduction of millions of works is shielded from the authors’ copyright claims.

The Authors Guild and its lawyers at Frankfurt Kurnit Klein & Selz set their sights on HathiTrust and the universities last September, after a different federal judge rejected a $125 million settlement in the parallel class action that the Guild and others brought directly against Google over its digitization efforts. The authors alleged that the HathiTrust project allowed Google “to back trucks up to university library loading docks” and scan every book for its own commercial use, not to mention for the unauthorized use of the universities themselves. “Nothing in copyright law,” they claimed, “permits the unlicensed scanning, copying and use of millions of copyrighted books, whether by a giant commercial entity like Google or a group of university libraries.”

Judge Baer roundly disagreed on Wednesday, siding with HathiTrust’s lawyers at Kilpatrick Townsend & Stockton and with other groups–including the National Federation for the Blind–who argued that the character and functions of the digitization project fell squarely within the space carved out in copyright law for fair use.

“The enhanced search capabilities that reveal no in-copyright material, the protection of Defendants’ fragile books, and, perhaps most importantly, the unprecedented ability of print-disabled individuals to have an equal opportunity to compete with their sighted peers in the ways imagined by the ADA protect the copies made by Defendants as fair use,” Baer ruled. (Here’s the judge’s 23-page decision, which resolves a series of dueling summary judgment motions.)

Barring a successful appeal, the decision spells the end to the Authors Guild’s claims related to HathiTrust. It’s not quite as clear what it means for the authors’ separate case against Google, but it certainly isn’t good. As we’ve reported, that case has been stayed by the U.S. Court of Appeals for the Second Circuit while it weighs Google’s appeal of a May decision granting class certification.

Judge Denny Chin (who’s overseeing the case in U.S. district court in Manhattan despite his elevation to the Second Circuit in 2010) ruled that the question of whether Google’s copying was fair use could be considered on a class-wide basis. But seven years into that litigation, he’s still never determined whether the fair use doctrine actually applies. Baer’s ruling this week provides more ammunition for Google and its lawyers at Durie Tangri and Wilmer Cutler Pickering Hale and Dorr to argue that it does.

HathiTrust counsel Joseph Beck and Joseph Petersen of Kilpatrick Townsend declined to comment on Baer’s decision. HathiTrust is a service of the University of Michigan; in a statement UM associate general counsel Jack Bernard said the university was “pleased with the decision, which we believe is in the public interest and will also benefit authors and publishers.”