[Greg Anos]

And here's the Canadian law...

6. The term for which copyright shall subsist shall, except as otherwise expressly provided by this Act, be the life of the author, the remainder of the calendar year in which the author dies, and a period of fifty years following the end of that calendar year.
R.S., 1985, c. C-42, s. 6; 1993, c. 44, s. 58.

Marginal note:Anonymous and pseudonymous works

6.1 Except as provided in section 6.2, where the identity of the author of a work is unknown, copyright in the work shall subsist for whichever of the following terms ends earlier:
(a) a term consisting of the remainder of the calendar year of the first publication of the work and a period of fifty years following the end of that calendar year, and
(b) a term consisting of the remainder of the calendar year of the making of the work and a period of seventy-five years following the end of that calendar year,
but where, during that term, the author’s identity becomes commonly known, the term provided in section 6 applies.
1993, c. 44, s. 58.

Since the names of the work for hire people has become known, Life + 50 applies, so only 159 Docs are P.D. in Canada, with the next block becoming P.D. in 2028, one more in 2029, and the last 3 in 2046... (Even though none of the writers or their heirs and assign ever got a dime of royalties for any of them (with one posthumous exception)).