Although a copyright registration is not required, the Copyright Act
establishes a mandatory deposit requirement for works published in the
United States. See the definition of "publication." In general, the
owner of copyright or the owner of the exclusive right of publication in
the work has a legal obligation to deposit in the Copyright Office,
within 3 months of publication in the United States, two copies (or in
the case of sound recordings, two phonorecords) for the use of the
Library of Congress. Failure to make the deposit can result in fines and
other penalties but does not affect copyright protection.
Certain categories of works are exempt entirely from the mandatory
deposit requirements, and the obligation is reduced for certain other
categories. For further information about mandatory deposit, request
Circular 7d "Mandatory Deposit of Copies or Phonorecords for the Library
of Congress." [http://www.loc.gov/copyright/circs/circ07d.pdf].
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