If use the J2SE code (which is GPL with classpath exception) you can't run the TCK. Without passing the TCK you can't call it Java, and you don't get the patent

If use the J2SE code (which is GPL with classpath exception) you can't run the TCK. Without passing the TCK you can't call it Java, and you don't get the patent license. See here: http://skife.org/java/jcp/2010/12/07/the-tck-trap.html http://skife.org/java/jcp/2010/12/07/the-tck-trap.html If you use the J2ME code, presumably you can get the TCK for mobile use (and associated patent protection), but the license doesn't include the classpath exception.