FOREIGN EDITIONS. In the case of works seeking ad interim copyright [2],
copies of a copyrighted work were exempted from the notice requirements
if they were first published outside the United States. Some copies of
these foreign editions could find their way into the United States
without impairing the copyright.

ACCIDENTAL OMISSION. The 1909 statute preserved copyright protection if
the notice was omitted by accident or mistake from a "particular copy or
copies." Unauthorized Publication. A valid copyright was not secured if
someone deleted the notice and/or published the work without
authorization from the copyright owner.

SOUND RECORDINGS. Reproductions of sound recordings usually contain two
different types of creative works: the underlying musical, dramatic, or
literary work that is being performed or read and the fixation of the
actual sounds embodying the performance or reading. For protection of
the underlying musical or literary work embodied in a recording, it is
not necessary that a copyright notice covering this material appear on
the phonograph records or tapes on which the recording is reproduced. As
noted above, a special notice is required for protection of the recording
of a series of musical, spoken, or other sounds that were fixed on or
after February 15, 1972. Sound recordings fixed before February 15, 1972,
are not eligible for federal copyright protection. The Sound Recording
Act of 1971, the present copyright law, and the Berne Convention
Implementation Act of 1988 cannot be applied or be construed to provide
any retroactive protection for sound recordings fixed before February 15,
1972. Such works, however, may be protected by various state laws or
doctrines of common law.