I have been very confused about what an "open standard" means. I know that part of the issue is that "open" has so many different meanings. This interview with Schulz helped clarify one of my confusions; the difference between a 'standard' and a 'specification.'<p>Some things I still don't understand: 1) an open standard must be royalty-free, but does it need to be available to others for no charge? Is it okay for there to be a fixed charge? What about one based on the size of the organization doing the purchase? (I'm thinking of POSIX here.)<p>2) "An open standard does not come with such hurdles as it comes with no legal barriers". How does that tie in with trademarks? Can I say "you can't say you meet standard X unless you pass the X conformance suite"?<p>3) Does an open specification need to be open to forking? That is, one legal barrier to upgrading a specification is the copyright protection on the previous spec. If some new group wants to implement standard X.2, it would be easier to start with X.1's text and modify a few places, rather than making a new spec from scratch, especially as the new group might mistranslate a couple of nuances that way. But most standards, e.g., the IETF ones, prohibit that sort of modification of existing specs.