Likely anything taped off-the-air from national networks is copyrighted.
Who owns the copyright for various material shown is murky.  The best
bet about obtaining a legal copy of something shown is to write to the
show itself or network "legal affairs" (or whatever a particular net
chooses to call such an office).  At the
end of some of the network magzine shows there are notices saying something
like "some of the stories may be available on video."
 
Cal Pryluck, Radio-Television-Film, Temple University, Philadelphia
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