the short: yes you could chown your own files in 1st to 5th editions, the first pwb was a derivition of 4th ed, so its not the originator of the idea. the long: that "superuser could not even chown setuid files" awoke a long dead memory. I needed to go back to read the 1st ed man entries for chown(1) and (2) again ( see http://cm.bell-labs.com/cm/cs/who/dmr/1stEdman.html inc. below) and it is documented that yes, one indeed could give away their own files. also note 1st ed was pre-gid, files had only owner and non-owner, so no setgid to worry about. looking more 2nd and 3rd ed were the same (see ttp://www.tuhs.org/Archive/PDP-11/Distributions/research/Dennis_v2/v2man.pdf and http://www.tuhs.org/Archive/PDP-11/Distributions/research/Dennis_v3/v3man.t…) however in the 3rd ed there were now gids yet no restistions on chown of setgid files. 4th and 5th ed still allowed file give away even if the setuid bit was set by stripping that bit out (unless superuser) (but did not strip the setgid bit) (see http://www.tuhs.org/Archive/PDP-11/Distributions/research/Dennis_v4/v4man.t… and http://www.tuhs.org/Archive/PDP-11/Distributions/research/Dennis_v5/v5man.p…) The 6th ed and on is when only the superuser could change file owners. Since the first PWBs were derived from 4th and 5th editions, they just did not buy into the new chown() restrictions from v6 (and added the missed strippig of the setgid bit) 1st Ed manual enries -- 11/3/71 CHOWN (I) NAME chown -- change owner SYNOPSIS chown owner file DESCRIPTION owner becomes the new owner of the files. The owner may be either a decimal UID or a name found in /etc/uids. Only the owner of a file is allowed to change the owner. It is illegal to change the owner of a file with the set-user- ID mode. FILES /etc/uids SEE ALSO stat DIAGNOSTICS BUGS OWNER ken, dmr 11/3/71 SYS CHOWN (II) NAME chown -- change owner of file SYNOPSIS sys chown; name; owner / chown = 16. DESCRIPTION The file whose name is given by the null-terminated string pointed to by name has its owner changed to owner. Only the present owner of a file (or the super-user) may donate the file to another user. Also, one may not change the owner of a file with the set-user-ID bit on, otherwise one could create Trojan Horses able to misuse other's files. FILES SEE ALSO /etc/uids has the mapping between user names and user numbers. DIAGNOSTICS The error bit (c-bit) is set on illegal owner changes. BUGS OWNER ken, dmr