A long-running copyright lawsuit between the Authors’ Guild and Google over its book-scanning project is over, and Google has won on the grounds that its scanning is “fair use.” In other words, the snippets of books that Google shows for free don’t break copyright, and Google doesn’t need the authors’ permission to engage in the scanning and display of short bits of books. The ruling (PDF) was published this morning by US District Judge Denny Chin, who has overseen the case since it was filed in 2005. The parties tried to settle this case, but the judge rejected the settlement as unwieldy and unfair. Now, the case has instead resulted in a hugely significant fair use win, that opens the door to other large-scale scanning projects in the future. Along with the First Sale doctrine, fair use is the most important limitation on copyright.