The item has no copyright markings on it as can be seen in the links above. At bottom left is Country of origin USA and-2910-this appears to pertain to the print job. At bottom left is This lobby display leased from Paramount Famous Lasky Corporation.
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.