The recent AMP v Myriad decision in the US Supreme Court explored subject matter excluded from patentability in the US. The Court held that a naturally occurring segment of DNA is a product of nature and is not eligible for patentability merely because it has been isolated. How the USPTO were to apply this decision generally (and the recent decision in Mayo v Prometheus) with respect to claims reciting or involving laws of nature/natural principles, natural phenomena and/or natural products has been eagerly awaited. Indeed, the USPTO has now issued a Guidance Memorandum and an associated Overview for its Examiner’s and for public consumption. The guidelines set out in the Memorandum will be required to be followed by USPTO Examiner’s and will apply to process, machine, manufacture or composition of matter inventions.

Setting aside the detail, the guidelines mandate the following as excluded from patent eligibility:

[C]hemicals derived from natural sources (e.g., antibiotics, fats, oils, petroleum derivatives, resins, toxins, etc.); foods (e.g., fruits, grains, meats and vegetables); metals and metallic compounds that exist in nature; minerals; natural materials (e.g., rocks, sands, soils); nucleic acids; organisms (e.g., bacteria, plants and multicellular animals); proteins and peptides; and other substances found in or derived from nature . . . regardless of whether particular words (e.g., “isolated”, “recombinant”, or “synthetic”) are recited in the claim.

As anticipated by many, the USPTO guidelines have applied the principles of the recent Supreme Court’s decisions liberally. As an example, claims directed to isolated chemical compounds per se (for example those useful as drugs/therapies), isolated antibiotics, isolated proteins per se(for example those associated with, or useful for the treatment of, disease), and isolated genes per se are no longer eligible for patent protection in the US.

However, despite this tightening by the USPTO of what constitutes patent eligible subject matter, of importance is that methods which make use of isolated chemical compounds, proteins, genes, etc remain patent eligible. Furthermore, with respect to molecular biology subject matter, claims to a geneper se can be pursued provided the gene is claimed as an isolated cDNA or as part of a recombinant expression construct as examples.

Needless to say, it will be very interesting to see how the USPTO guidelines play out during examination of patent applications and how long before they are appealed to the Federal Circuit – or indeed if future Supreme Court decisions require another shift of the goal posts.