I recently wrote how the Supreme Court of the United States had ruled that isolated DNA was not a patentable invention. The Court ruled that a naturally occurring DNA segment is a product of nature and is therefore not patentable subject matter simply because it had been isolated. At the time, I suggested that this decision could be problematic for chemists who isolate natural products. As anticipated, the United States Patent and Trademark Office (USPTO) released an 18-page document this past March titled Guidance For Determining Subject Matter Eligibility Of Claims Reciting Or Involving Laws of Nature, Natural Phenomena, & Natural Products. It details how patent examiners should apply the principles laid down by the Court with respect to any claim “reciting or involving laws of nature/natural principles, natural phenomena, and/or natural products.” These guidelines represent a significant change to US patent law that could have far-reaching consequences with respect to innovation and investment in the chemical industries.

While the subject matter of the Supreme Court’s decision was limited to isolated DNA, the USPTO’s guidelines have much further reach as to what is considered a natural product. The guidelines provide that the following list of products may not be patent eligible in the United States: chemicals derived from natural sources (antibiotics, fats, oils, petroleum derivatives, resins, toxins, etc.); foods (fruits, grains, meats and vegetables); metals and metallic compounds that exist in nature; minerals; natural materials (rocks, sands, soils); nucleic acids; organisms (bacteria, plants and multicellular animals); proteins and peptides and other substances found in or derived from nature.

The guidelines provide several examples of how a patent examiner will assess a claim directed to a natural product. For example, a claim directed to the purified natural product 2-methyl-2-pentenoic acid, isolated from strawberries, would no longer be considered patentable subject matter. In other words, though a claim to the compound itself could meet two of the major requirements for patentability (novelty and inventiveness), an inventor would not be able to obtain patent protection simply because 2-methyl-2-pentenoic acid is a product of nature.

The guidelines contain another example that is worthwhile to review as it demonstrates how patent ineligible subject matter can become patent eligible based on the specific wording of the claim. A composition containing 90 percent copper and 10 percent tin is deemed to be patent ineligible. The reason offered is that a simple mixture or aggregation of two metals, which exist in nature, does not change the metals as they exist. However, claiming 90 percent copper and 10 percent tin as an alloy is deemed patent eligible as human manipulation is required to arrive at such a product.

The Supreme Court decision and the resulting guidelines represent a significant change in US patent law, especially with respect to pharmaceutical, chemical and biotechnology inventions. It certainly doesn’t mean that those involved in the research of natural products and other naturally derived chemicals and materials should put down their test tubes. However, it’s important to recognize that the landscape has shifted. A key consideration in the analysis is that the claimed subject matter be “created by human manipulation.” Those involved in such research should be mindful to include embodiments that would result in naturally derived chemicals being outside the realm of products which exist in nature. For instance, including claims to purity, accurate melting points, crystal forms etc., would make it more difficult for an examiner to argue that these different forms or properties exist in nature. But until US courts interpret these guidelines, patentable subject matter of unmodified natural products will remain in flux.