[wildfly-dev] Question about usage of jboss spec versions

Hello, This is probably stupid question but I was recently wondering, what's the actual reason why WFLY (and other RH technologies) use jboss versions of all the specs? For instance https://github.com/jboss/jboss-annotations-api_spec instead of just picking up the javax.annotation artifact. The contents are pretty much the same, so I think I have to be missing something trivial and obvious.. Is it historical reasons? Or perhaps a matter of licenses and productization? Matej