"This court should reject the proposed settlement in its current form and encourage the parties to continue negotiations," reads a filing the DoJ submitted to a US court.
The proposed settlement must be modified by Google and the authors and publishers that bought the lawsuits, so that it complies with US copyright and antitrust laws, the DOJ said.
The Authors Guild and the Association of American Publishers (AAP) filed the lawsuits after Google launched a program to scan and index sometimes entire collections from the libraries of major universities without always getting permission from the copyright owners of the books.
Google made the text of the books searchable on its book search engine, claiming it's protected by the fair use principle because it only showed snippets of text for in-copyright books it had scanned without permission.
However, after two years of negotiations, Google, the Authors Guild and the APP struck a deal that allowed the materials to still be made available online, but would require web users to purchase the lifetime rights to read and print scanned books searched through Google.
The deal also included the creation of the Book Rights Registry - a royalty system to compensate authors and publishers for access to their works.
The Registry, whose board of directors would be made up of an equal number of author and publisher representatives, would also locate and register copyright owners, who in turn have the option to request to be included in or excluded from the project.
The DOJ also expressed concern that the proposed settlement doesn't satisfy the requirements of Federal Rule of Civil Procedure 23, which sets parameters for approving settlements of class action lawsuits.
"We are considering the points raised by the Department and look forward to addressing them as the court proceedings continue," Google and the Authors Guild and the AAP said.
The DOJ's Antitrust Division continues investigating the settlement, the DOJ said. It revealed its filing contains "a preliminary explanation" of the agency's antitrust concerns.
Despite its criticisms, the DoJ said it recognises that a settlement of the case would benefit the public by making millions of hard-to-find books easily accessible in digital form.
Since the DOJ hasn't completed its antitrust investigation, it can't state that the proposed agreement violates antitrust law, but it does have serious concerns in this area. Iit seems to the DoJ that the agreement gives book publishers power to restrict price competition. The DoJ is also worried the agreement could shut out other digital distributors from competing with Google.