U.S. is that the invention being patented is not obvious, meaning that a "person having ordinary skill in the art" (PHOSITA) would not know how to solve the problem at which the invention is directed by using exactly the same mechanism. Since the PHOSITA standard turned to be too ambiguous in practice, the U.S. Supreme Court provided later two more useful approaches which currently control the practical analysis of non-obviousness by patent examiners and courts: Graham et al. v. John Deere Co. of Kansas City et al., 383 U.S. 1 (1966) gives guidelines of what is "non-obvious", and KSR v. Teleflex (2006) gives guidelines of what is "obvious". See also Priority right Cripps question References Further reading G. Knesch, Assessing Inventive Step in Examination and Opposition Proceedings in the EPO, epi Information 3/1994, pp. 95–101. External links European Patent Convention ("Inventive step") Could-would approach ("Could-would approach") and Technical Board of Appeal decision T2/83 of 15 March 1984. Patent law