Google has put the brakes on its programme to digitise the books in several major university libraries.
The New York Public Library is taking part in the project
In its blog, the search giant said it would temporarily stop scanning copyrighted texts until November to allay concerns about the plan.
The company's library project aims to put millions of volumes online and accessible everywhere via the web.
Google's plan has come under fire from several groups who object to what they say are violations of copyright.
Google is pumping $200m (£110m) into creating a digital archive of millions of books from four top US libraries - the libraries of Stanford, Michigan and Harvard universities, and of the New York Public Library - by 2015.
It is also digitising out-of-copyright books from the UK's Oxford University.
Google says the aim is to make the text of the world's books searchable by anyone in the world, especially when it comes to out of print and obscure texts.
"We think most publishers and authors will choose to participate in the publisher programme in order introduce their work to countless readers around the world," wrote Google Print's Adam Smith on the Google blog.
"But we know that not everyone agrees, and we want to do our best to respect their views too."
In an attempt to assuage concerns about copyright, Google has stopped scanning books which are in copyright until November.
The pause is designed to allow publishers to tell Google which books should not be included in the scanning programme.
But the changes do not seem to go far enough for leading publishers.
The trade body of the US publishing industry, the Association of American Publishers (AAP), said it still has "grave misgivings" about the project.
"Google's announcement does nothing to relieve the publishing industry's concerns," said AAP president Patricia Schroeder in a statement.
"Google's procedure shifts the responsibility for preventing infringement to the copyright owner rather than the user, turning every principle of copyright law on its ear," she added.