(AP) — A federal judge in New York has granted class certification to authors challenging Internet search leader Google over its plans for the world's largest digital library.

Judge Denny Chin ruled in a written decision Thursday that class action is "more efficient and effective than requiring thousands of to sue individually." He says requiring each author to sue Google Inc. would risk disparate results in nearly identical lawsuits and exponentially increase the cost of litigation.

The Authors Guild had sought class certification. Google already has scanned more than 20 million books for the project. The rejected Google's attempt to toss The Authors Guild from the case.

Mountain View, California-based Google said in a statement Thursday that it's "confident that is fully compliant with copyright law."