Non-obviousness is term used in US patent law to describe one of the three requirements that an invention must meet to qualify for patentability. One of the main requirements of patentability is that the invention being patented is not obvious, meaning that a "person having ordinary skill in the art" would not know how to solve the problem at which the invention is directed by using exactly the same mechanism.
For example, in a recent case, Smuckers attempted to patent peanut butter and jelly sandwiches with crimped edges instead of crusts. This invention was challenged in court, and the court ruled that the crimping method, which was essentially the same as that used for ravioli, was an obvious means of protecting the contents of the sandwich. The patent was therefore voided for failing the nonobviousness test.
Inventive step is a similar test under European Patent law.
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