HOW TO SECURE A COPYRIGHT
Copyright Secured Automatically upon Creation
The way in which copyright protection is secured is frequently misunderstood.
No publication or registration or other action in the Copyright Office is required to secure copyright. (See following Note.) There are, however, certain definite advantages to registration. See "Copyright Registration."
Copyright is secured automatically when the work is created, and a work is "created" when it is fixed in a copy or phonorecord for the first time. "Copies" are material objects from which a work can be read or visually perceived either directly or with the aid of a machine or device, such as books, manuscripts, sheet music, film, videotape, or microfilm. "Phonorecords" are material objects embodying fixations of sounds (excluding, by statutory definition, motion picture soundtracks), such as cassette tapes, CDs, or LPs. Thus, for example, a song (the "work") can be fixed in sheet music (" copies") or in phonograph disks (" phonorecords"), or both.
If a work is prepared over a period of time, the part of the work that is fixed on a particular date constitutes the created work as of that date.
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NOTE: Before 1978, federal copyright was generally secured by the act of publication with notice of copyright, assuming compliance with all other relevant statutory conditions. U. S. works in the public domain on January 1, 1978, (for example, works published without satisfying all conditions for securing federal copyright under the Copyright Act of 1909) remain in the public domain under the 1976 Copyright Act.
Certain foreign works originally published without notice had their copyrights restored under the Uruguay Round Agreements Act (URAA). Request Circular 38b and see the "Notice of Copyright" section of this publication for further information.
Federal copyright could also be secured before 1978 by the act of registration in the case of certain unpublished works and works eligible for ad interim copyright. The 1976 Copyright Act automatically extends to full term (section 304 sets the term) copyright for all works, including those subject to ad interim copyright if ad interim registration has been made on or before June 30, 1978.
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kilde:
http://www.copyright.gov
Endvidere gælder det for alle medier (bøger, billeder, film, musik etc) at et copyright er gældende i 70 år EFTER kunstnerens død.