There is " Litho Co NY" at lower right--I can't make out the name of the company who did the work of printing the poster.
Copyright searches for original registrations were done in both artwork and film. The search in artwork for 1934 turned up nothing for Celebrity or Iwerks. The search for original registrations turned up the titles at the link, p. 411, but not this title. There's no evidence of original registration for this film or its artwork.
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.