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Scientific and technological advances in nanopharmaceuticals bring the doctrine of inherent obviousness to a head. On the one hand, nanotechnology promises to offer novel ways to target and treat traditionally incurable diseases by operating at a scale that is comparable to the scales that most biological systems use. On the other hand, nanotechnology inventions that result in improved pharmacokinetic properties are susceptible to validity challenges based on inherent obviousness.

Inherency and obviousness are two independently recognized and well-understood principles in United States patent law. Inherency refers to a claimed limitation or feature that is either necessarily present in, or the natural result of, the features expressly disclosed by the prior art. Obviousness, in contrast, refers to whether the claimed invention as a whole was readily apparent in the prior art based on a combination of references. Because inherency turns on whether something was necessarily present in the prior art at some earlier time, the analysis implicates hindsight. But because obviousness turns on what would have been obvious to a person having ordinary skill in the art at the time the invention was made, the analysis forbids hindsight.

Despite the seemingly mutual exclusivity between inherency and obviousness, the two principles have been increasingly applied together in the context of pharmaceutical and biotechnology inventions. Patent challengers frequently rely on the argument that improved pharmaceutical concentration and bioavailability at the target site is implicit in prior art teachings concerning how pharmaceutical particles behave at decreased sizes despite the novelty of the particle’s size alone. Rather than engage in an arbitrary analysis focusing on how unexpected some pharmacokinetic response is, courts and the USPTO should eradicate the concept of inherent obviousness in its entirety.