For works created before 1978, but not published or registered before 1978, the standard §302 copyright duration^{[clarification needed]} also applies. Prior to 1978, works had to be published or registered to receive copyright protection. Upon the effective date of the 1976 Copyright Act (which was January 1, 1978) this requirement was removed and these unpublished, unregistered works received protection. However, Congress intended to provide an incentive for these authors to publish their unpublished works. To provide that incentive, these works, if published before 2003, would not have their protection expire before 2048.^{[citation needed]}

All copyrightable works published in the United States before 1923 are in the public domain;^[38] works created before 1978 but not published until recently^[when?] may be protected until 2047.^[39] For works that received their copyright before 1978, a renewal had to be filed in the work's 28th year with the Copyright Office for its term of protection to be extended. The need for renewal was eliminated by the Copyright Renewal Act of 1992, but works that had already entered the public domain by non-renewal did not regain copyright protection. Therefore, works published before 1964 that were not renewed are in the public domain.