550 U.S. 398 (2007) Cited 1,547 times 185 Legal Analyses
Holding that, in an obviousness analysis, "[r]igid preventative rules that deny factfinders recourse to common sense, however, are neither necessary under our case law nor consistent with it"
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"
Holding that a person of skill in the art would have expected amitriptyline to resemble imipramine in the alleviation of depression in humans because of the drugs’ close structural similarity and similar use