http://www.economist.com/blogs/democracyinamerica/2015/10/words-masses?fsrc=scn/tw/te/bl/ed/wordsforthemasses
Reproducing too many of somebody else’s words for profit and without adding value to the work generally constitutes a copyright infringement. But if a reasonable portion is spun into parody or criticism, or if the work is put to a “transformative purpose”, it counts as permissible “fair use” under the Copyright Act of 1976.
Google Books does a transformative act. Ruled the judge.