It's the INSTALL.txt file, not a copyright file. I have not (yet) been able to find a copyright or license file that directly applies to the sources in CVS, either on the website or in CVS itself. Anyone who knows where the heck the thing is hiding, do tell. :)
look in src/distrib/notes/legal i think. i don't think TNF itself is that interested in removing it's clause3 as many have expressed interest in keeping it. personally i'm all for it going away (i removed the clause3 from all my code in netbsd several years ago.) (there is a newly elected board and they are the ones who will make any changes, perhaps things are better than i think they are.) .mrg. ps: TNF = the netbsd foundation, the legal entity, etc..
