NEW YORK, USA: Google Inc has reached a legal settlement with authors and major publishers that pave the way for readers to search through millions of copyrighted books online, browse passages and purchase copies.

Under Tuesday's settlement, Google will pay $125 million to create a Book Rights Registry, were authors and publishers can register works and receive compensation from institutional subscriptions or book sales.

The settlement with the Authors Guild and the Association of American Publishers draws to a close a three-year legal challenge of Google's plan to make many of the world's great books searchable online.

The lawsuit filed by publishers McGraw-Hill Cos Inc, Pearson Plc's Pearson Education and Penguin Group (USA) units, CBS Corp's Simon & Schuster and John Wiley & Sons Inc charged that Google's attempts to scan works without permission infringed on copyright protections.

At issue were rights of copyright holders versus the public's "fair use" interest in being free to use limited portions of books for commentary or review, for what resembles a kind of full-text, searchable card catalog.

The settlement is subject to federal court approval.

"It's been a long and arduous negotiation," said Paul Aiken, executive director of the Authors Guild, calling the settlement "the biggest book deal in U.S. publishing history."

Aiken said the settlement will mean a "vast repository of books -- millions upon millions of out-of-print books and many in-print books -- will find a new home and new readers online."

Initially, Google's Print Library Project called for searches to bring up three- or four-line snippets from books, but plans now call for as much as a full page to appear in response to queries.

In addition, libraries across the country will be offered an online portal, allowing their patrons to print pages for a fee. Institutional subscriptions will also be available to college students and faculty.