The item has no copyright markings on it as can be seen in the links above. Ar bottom left is a Mascot Pictures logo and a box with "Blazing the Trail"-the company's Broadway address in New York city in it and Country of origin USA. At bottom right are 4 numers which probably pertain to the printing of 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 1931 film ''The Lightning Warrior''. |Source=[http://1.bp.blogspot.com/-yLTEWuqRlyY/T4z0sLRhueI/AAAAAAAAFqQ/LF-hd4kLiY8/s1600/The+Lightning+Warrior+ch+12+-+1sht.jpg source] |Date=[http://www.imdb.com/title/tt00...