Affirming conclusion that toothbrush and small hair brush were in same field of endeavor because "the structural similarities between toothbrushes and small brushes for hair would have led one of ordinary skill in the art working in the specific field of hairbrushes to consider all similar brushes including toothbrushes"
35 U.S.C. § 103 Cited 6,172 times 492 Legal Analyses
Holding the party seeking invalidity must prove "the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains."