Rob Riggs writes: Jarek Duda, the inventor of a compression technique called asymmetric numeral systems (ANS), dedicated the invention to the public domain. Since 2014, Facebook, Apple, and Google have all created software based on his breakthrough. Google is now trying to patent a video encoding scheme using the compression technique. The inventor is fighting Google in the European courts and has won a preliminary ruling. The fight's not over and Google is also seeking a patent with the USPTO. A Google spokesperson says Duda came up with a theoretical concept that isn't directly patentable, "while Google's lawyers are seeking to patent a specific application of that theory that reflects additional work by Google's engineers," reports Ars Technica. "But Duda says he suggested the exact technique Google is trying to patent in a 2014 email exchange with Google engineers."