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Re: Can a recipients rights under GNU GPL be revoked?

Note that under USA law the right to *use* (including the right to make
such transient and temporary copies as might be required for effective
use) a copy of a program of which one is a legitimate owner is automatic
and requires no license.  Thus if someone gives (or sells) a copy of a
GPL licensed program to you, you are not affected by the GPL until you
make a copy of your copy and then give or sell it to someone else (or
retain a copy after passing the one you received on).

John Hasler 
Elmwood, WI USA