From time to time critics of the old Bell System gripe that the
> company was "guaranted profits" by the regulators and as such, owed
> something back to the community.
> Aside from the fact that regulation actually limited profits, AT&T was
> indeed required to give things back. One of which was the rights to
> its invention of the transistor, which were available free of charge.
> (Per Ziff-Davis history).
> I had always wondered why AT&T never seemed to make any money from the
> invention of the transistor.
You seem misinformed. Yes, AT&T allowed other companies to "borrow" the transistor invention, but they didn't do this with a smile on their face. It was one of the many concessions made during one the many antitrust concerns. AT&T was kind of in a bind with antitrust concerns due to the technology and markets at the time and were stuck between breaking up the company or continuing to make such deals -- which were short lived. The government had plenty of antitrust actions with AT&T over the years before the last antitrust case which of course ended in 1983. If AT&T had kept the rights to the transister, it would probably be a completely different company today -- that's how big that one invention was.