The strange co-existence of two characters each named "Dennis the Menace"
Independent creation is a defense in copyright law:
“Bolton and Goldmark also contend that their witnesses rebutted the Isley Brothers' prima facie case of copyright infringement with evidence of independent creation. By establishing reasonable access and substantial similarity, a copyright plaintiff creates a presumption of copying. The burden shifts to the defendant to rebut that presumption through proof of independent creation. See Granite Music Corp. v. United Artists Corp., 532 F.2d 718, 721 (9th Cir.1976). See Three Boys Music Corp. v. Bolton, 212 F.3d 477, 486 (9th Cir. 2000).”
One of the more interesting examples of "independent creation" is the name "Dennis the Menace" given to two different comic strips in March 1951, one in the US and one in Britain. Other than the name, the two "Dennis's" bear little in common, and have co-existed for over 50 years.
Independent creation is not a defense in patent law.
**Separately, from blawgsearch on 5 Nov 2016