Google's controversial plan to scan millions of books and sell them online has finally been given the green light by a New York court.
US circuit judge Denny Chin dismissed an eight-year-old lawsuit by authors and accepted that scanning books and making text available for online searches constituted “fair use” under US copyright law.
Google had estimated that it could owe more than $3bn if the class action had succeeded.
In 2005, the US Authors Guild sued Google, alleging that its plans to create a digital library amounted to massive copyright infringement.
Opponents to the plan, led by Microsoft and Yahoo, claimed that the digitisation of millions of out of print books would give Google an unfair advantage.
But Google said its plans constituted "fair use" because it was only putting excerpts of texts online, an argument that judge Chin has now accepted.
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He also said the digitisation was "transformative," would provide “significant public benefits,” and could be expected to boost rather than reduce book sales.
The decision could be a significant milestone for the long-running legal battle between Google, the Authors Guild and US publishers, according to the BBC.
Publishers and authors began joint legal action over the scanning project in 2005. This lead to a settlement agreement in 2008, which required Google to pay $125m into a fund to compensate writers whose copyrighted works appeared in the online library. The agreement also placed restrictions on how much of a book Google could make searchable.
However, in March 2011, the settlement agreement was rejected by judge Chin because he said it would give Google a "de facto monopoly" to copy books.
This led to separate negotiations by US publishers who reached a settlement agreement with Google in October 2012, but financial terms of the deal were not disclosed.
The latest ruling by judge Chin comes after a US circuit court of appeals found that he had prematurely certified a class of authors without first evaluating the fair use defence, according to the Guardian.
In April 2013, Google said it had scanned more than 30 million works ready for inclusion in its digital library.
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Google has confirmed plans to launch a digital bookstore before the end of the year that will step up competition with Amazon and Apple.