characterize what the 3rd-party material might be?
Me personally, no. But there are others on the list who can help do this.
Hopefully they will chime in!
Here's a list, gathered from the manuals, of stuff that Bell Labs
may not have the right to redistribute, with some (uncertain)
attributions of origin. I did not check to see which of them appear in
the TUHS archives; I doubt that /usr/src fully covered /bin and /usr/bin.
This list is at best a first draft. Please weigh in with corrections.
Kernel internet code. BSD
lisp, liszt, lxref MIT
icont, iconc Arizona
more BSD (From the manpage: "More, a paginator that lives up to its name, has
too many features to describe." Its prodigality has been eclipsed by
pascal, pc BSD
readnews, checknews, postnews Duke
vi, ex, edit BSD
Commands I'm not sure about, could be from Bell Labs
adventure, zork, aarvark, rogue
trek, ogre, sol, warp, sail
Games I'm not sure about