question: Who pointed out that `` if copyright were a natural right nothing could justify terminating this right after a certain period of time '' ?
answer: Stallman
turker_answer: Stallman pointed out that `` if copyright were a natural right nothing could justify terminating this right after a certain period of time '' .
rule-based: Pointed out Stallman that `` if copyright were a natural right nothing could justify terminating this right after a certain period of time '' .