a satellite question-- exclusivity?

[Donna Halper <dlh@donnahalper.com>]

Tonight during the news of a tragic plane crash, CNN switched off to the
CBC and began to carry them live.  A few minutes later, NBC came on with a
bulletin and ran the same CBC feed.  I was wondering-- when I worked for
ABC in the early 70s, we had an agreement that ONE station per market got
our feeds.  Has that changed?  In other words, how can several stations
from competing networks carry the same report or the same feed?  I have
seen this not just emergencies (perhaps there are special dispensations
given in a crisis?).  Does anybody know what the rule is, and is it the
same for radio as well as TV?  (With all the consolidation, can the same
report appear on stations that are with competitive networks, in other
words?)  

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