In the majority of circumstances where the artist is the copyright holder, copyright lasts for the rest of the artist's life and for 70 years after. After this period of time, copyright will no longer exist. However, galleries in possession of much older works of art can copyright images of this art for use on promotional material.
If art work has been specifically commissioned or completed during employment, in most cases the copyright no longer remains with the artist. In these circumstances, the copyright usually stays with the commissioner of the art work or the employer for whom the art work was produced, unless agreed otherwise. Freelance artists should bear this in mind when producing art work for companies or commissioners.
Excluding commissions and art work produced during employment, the artist will become the copyright holder of his own work as soon as he creates it. But if the artist sells a piece of art, it can be difficult to prove who the copyright holder is unless quality photos of the art, including the dates produced, can be presented. The limitation with proof is that if the high-quality images are found and copied, copyright infringement can occur.
The artist, or copyright holder, has the right to reproduce the original artwork as much as desired in any medium, such as for greeting cards or calendars. Anyone else who wishes to reproduce the art work must seek the copyright holder's permission first. Galleries and publishers are able to reproduce images for use in advertisements, but cannot profit from the reproductions. The reproduction rights can be sold while full copyright remains with the artist or copyright holder.