How long does a copyright last?

For works published after 1977, the copyright lasts for the life of the author plus 70 years. However, if the work is a work for hire (that is, the work is done in the course of employment or has been specifically commissioned) or is published anonymously or under a pseudonym, the copyright lasts between 95 and 120 years, depending on the date the work is published. All works published in the United States before 1923 are in the public domain. Works published after 1922, but before 1964, are protected for 95 years from the date of publication, if a renewal was filed with the Copyright Office during the 28th year after publication. If no renewal was filed, such works are in the public domain. Works published from 1964 to 1977 are protected for 95 years whether or not a renewal was filed. If the work was created, but not published, before 1978, the copyright lasts for the life of the author plus 70 years. And if such a work was published before 2003, the copyright lasts until December 31, 2047.