Since the issue was raised on this mailing list, I checked with Carnegie Mellon's
legal department regarding our rights in the name "Coda" (referred to
as the "Coda mark" in trademark law).

Apparently, Panic filed a trademark application with the United States
Patent and Trademark Office to register the Coda  mark in the category of
states that they started using the Coda mark in April 2007.

Our legal department confirmed that, since CMU has used the Coda mark
in connection with the Coda File System for approximately 20 years,
CMU has common law rights in the Coda mark (in connection with the File System).
As a result of CMU's common law rights, regardless of whether Panic is
successful in obtaining a registered trademark for "Coda", CMU can continue
to use the Coda mark for the Coda File System (and Panda's registration
does not and cannot prevent CMU from doing this.)