English: Poster for the 1957 film The Brain from Planet Arous.
The item has no copyright markings on it as can be seen in the links above. At bottom is the following: One Sheet Printed in USA, and "Property of National Screen Service Corp. Licensed for display in connection with the exhibition of this picture at your theatre. Must be returned immediately thereafter."
This work is in the public domain in the United States because it was published in the United States between 1929 and 1977, inclusive, without a copyright notice. For further explanation, see Commons:Hirtle chart as well as a detailed definition of "publication" for public art. Note that it may still be copyrighted in jurisdictions that do not apply the rule of the shorter term for US works (depending on the date of the author's death), such as Canada (50 p.m.a.), Mainland China (50 p.m.a., not Hong Kong or Macao), Germany (70 p.m.a.), Mexico (100 p.m.a.), Switzerland (70 p.m.a.), and other countries with individual treaties.