Patentability and infringement of product-by-process claims

A product-by-process claim is a mechanism for claiming a product that cannot be adequately described by its structure. A literal reading of a product-by-process claim suggests that an accused product can literally infringe on a product-by-process claim only if the accused product is made by the process of the product-by-process claim. But, prior to the recent decision in Abbott Laboratories v. Sandoz, Inc., Appeal No. 2007-1400, decided May 18, 2009, product-by-process claims were not read literally when it came to infringement – infringement of a product-by-process claim was based on the product itself rather than on the process used in making the product. The en banc court in Abbott Laboratories v. Sandoz, Inc. moved towards the literal reading of product-by-process claims, which provoked a long dissent by a number of the Circuit judges – something along the lines of the en banc court being rash in making a decision to overturn a longstanding precedent, failing to consider the effect of the decision on, for example, “today’s complex and biological products whose structure may be difficult to analyze with precision” and those who may be relying on the old way of determining infringement of product-by-process claims.

The Abbott Laboratories v. Sandoz, Inc. case did not review requirements for patentability inquiry of product-by-process claims. But certain lessons can nonetheless be gleaned from the case. For example, consider a product A that is claimed as a product made by a process B because it cannot be claimed adequately by its structure. For the product-by-process claim to be patentable, the product-by-process claim must be novel under 35 USC 102 and non-obvious under 35 USC 103. Based on Abbott Laboratories v. Sandoz, Inc., the patentability inquiry can involve finding a product C that is made by a process D, where the process D anticipates or renders obvious process B. Without the decision in Abbott Laboratories v. Sandoz, Inc., the patentability inquiry might involve finding a product C that has a structural definition that anticipates or renders obvious the structural definition of product A. This may require that product A is so broadly defined structurally that the structural definition reads on a wide variety of products with which product A does not share many structural characteristics or shares trivial structural characteristics. By interpreting product A as being limited by the process with which it was made, it is possible to avoid the witch hunt and more easily carry out the patentability inquiry.

But nothing is straightforward in patent law – this approach of focusing on the process in the patentability inquiry of a product-by-process is not irreproachable. On one hand, it is possible that product A made by process B might have structural characteristics that are indistinguishable from that of product C made by process D. Ordinarily, this would render product A unpatentable in view of product C. On the other hand, a finding that product A has structural characteristics that are indistinguishable from that of product C is not necessarily a proof that product A is indistinguishable from product C since product A may have properties that are not measurable or that are difficult to measure. On the plus side, the approach, though imperfect, would yield uniform patentability inquiry results across various fields of technologies.