Authors are split over the
Amazon has urged a New York court to reject a deal that would allow Google to build a vast digital library.
The online retailer says that if Google is given exclusive rights to scan books for use on the internet, it is "likely to lead to a monopoly".
Interested groups and authors have until 28 January to file objections to the project to a US court.
Google says the project will "unlock access to millions of books" and give authors new ways to distribute books.
Google Books aims to scan millions of books worldwide and make them available - and searchable - online.
It was first launched in 2004 but was put on hold a year later when the Authors Guild of America and Association of American Publishers sued over "massive copyright infringement".
As a result, in 2008 Google agreed to pay $125m (£77m) to create a Book Rights Registry, where authors and publishers could register works and receive compensation.
A decision on whether the deal could go through was originally scheduled for early October.
But, the presiding Judge sent the deal back to the drawing board after criticism and objections from around the world.
Groups have until 28 January to file objections to the revised settlement to a US court, which will decide whether to approve it. Authors have the same deadline to opt-out of the project.
A fairness hearing has then been set for 18 February.
In the run up to the deadline, industry and authors have once again started mounting pressure on Google.