To assess the innovative step for an innovation patent, the invention as claimed in each claim (not the identified 'advance in the art') must be compared with each prior disclosure, and variations must be assessed for whether they make a real contribution to the working of the claimed device as a whole; features cannot be dismissed as 'desiderata' merely because they are known in the common general knowledge.
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5 of the 18 citing cases carry a classified treatment. How each court treated it is available to signed-in members.