Does AT&T use Unix?

[Dave Hammond]

This is a silly little question which arguably might have been posted
to comp.misc, however its Unix related:

Does anyone have information concerning where (if at all) Unix is applied
in AT&T's non-Unix business divisions?  For example, do long distance
operators use Unix workstations, or are network call routing systems
Unix-based, or is AT&T's billing done on Unix machines?

Just an idle curiosity ...

--
Dave Hammond
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