English: Copy of the cartoon strip The Gumps from 1926.
A search was done for copyright renewal in both artwork and publications for Chicago Tribune, Gumps and Sidney Smith for the years 1953 and 1954. There were no listings for any of these keywords; there's no evidence that copyright continues to be claimed on this.
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 (70 years p.m.a.), Mainland China (50 years p.m.a., not Hong Kong or Macao), Germany (70 years p.m.a.), Mexico (100 years p.m.a.), Switzerland (70 years p.m.a.), and other countries with individual treaties.