The item has no copyright markings on it as can be seen in the links above. At bottom is Country of origin USA, Morgan Litho Co., Cleveland, O. and a number which probably refers to the print job for the poster.
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.
{{Information |Description=Poster for the 1940 film ''In Old Missouri''. |Source=[http://www.ebay.com/itm/In-Old-Missouri-One-Sheet-Movie-Poster-The-Weaver-Brothers-amp-Elviry-1940-/201187367137?pt=LH_DefaultDomain_0&hash=item2ed7b398e1&nma=true&si=89B...