Otto Messmer, American cartoonist and animator, co-created Felix the Cat (d. 1983)
Otto James Messmer (August 16, 1892 – October 28, 1983) was an American animator known for his work on the Felix the Cat cartoons and comic strip produced by the Pat Sullivan studio.

The extent of Messmer's role in the creation and popularity of Felix is a matter of ongoing dispute, particularly as he only laid his claim to the character after the death of Sullivan, who until that time had received the credit.