USPTO Patent Eligibility Guidelines: A Topsy Turvy Approach for Natural Products

Critics of the latest Myriad/Mayo patent-eligibility guidelines (and there will be many) will no doubt be puzzled by the proposed approach to the patenting of natural products.

The Myriad/Mayo guidelines include an example that discusses the patent eligibility of a purified amazonic acid. The USPTO guidelines read as follows:

“The Amazonian cherry tree is a naturally occurring tree that grows wild in the Amazon basin region of Brazil. The leaves of the Amazonian cherry tree contain a chemical that is useful in treating breast cancer. However, to be effective, a patient must eat 30 pounds of the leaves per day for at least four weeks. Many have tried and failed to isolate the cancer-fighting chemical from the leaves. Applicant has successfully purified the cancer-fighting chemical from the leaves and has named it amazonic acid. The purified amazonic acid is structurally identical to the amazonic acid in the leaves, but a patient only needs to eat one teaspoon of the purified acid to get the same effects as 30 pounds of the leaves…”

The view of the USPTO now is that a claim to purified amazonic acid is not patent-eligible because there is no structural difference between the purified acid in the claim and the acid in the leaves, and the claim does not include features that demonstrate that the recited product is markedly different from what exists in nature. However the proposition that only a structural difference suffices and that differences e.g. in purity and utility do not suffice is derivable neither from the opinion in Prometheus nor from the opinion in Myriad. It is abundantly clear from study of the opinion in Myriad that the reasons why the BRCA1 gene claim did not survive were that the gene had been defined in terms of its informational content rather than its chemical structure, and that no new utility for the isolated full-length gene had been disclosed. Such an interpretation is wholly consistent with the concession made on behalf of the Petitioners in oral argument.

It is, to say the least, unclear why the USPTO, without public consultation seeks to remove the patent-eligibility of isolated or purified natural products of new medical or other utility, which has been taken as a given in the US for 100 years and is consistent with practice in Europe and other major industrialised countries.

This scenario in the new guidance makes it clear beyond dispute that it was directly derived from the scenario in oral argument in Myriad. The relevant exchanges with counsel for the petitioners in oral argument in Myriad establish that the point was considered to be well-settled:

“JUSTICE GINSBURG: Mr. Hansen, Respondents say that isolating or extracting natural products, that has long been considered patentable. Examples were aspirin and whooping cough vaccine. How is this different from natural products? …….

JUSTICE ALITO: Can I take you back to Justice Ginsburg’s question, because I’m not sure you got at what troubles me about that. Suppose there is a substance, a chemical, a molecule in the leaf – the leaves of a plant that grows in the Amazon, and it’s discovered that this has tremendous medicinal purposes. Let’s say it treats breast cancer. A new discovery, a new way is found, previously unknown, to extract that. You make a drug out of that. Your answer is that cannot be patented; it’s not eligible for patenting, because the chemical composition of the drug is the same as the chemical that exists in the leaves of the plant.

MR. HANSEN: If there is no alteration, if we simply pick the leaf off of the tree and swallow it and it has some additional value, then I think it is not patentable. You might be able to get a method patent on it, you might be able to get a use patent on it, but you can’t get a composition patent.

JUSTICE ALITO: But you keep making the hypotheticals easier than they’re intended to be. It’s not just the case of taking the leaf off the tree and chewing it. Let’s say if you do that, you’d have to eat a whole forest to get the value of this. But it’s extracted and reduced to a concentrated form. That’s not patent eligible?

MR. HANSEN: No, that may well be eligible, because you have now taken what was in nature and you’ve transformed it in two ways. First of all, you’ve made it substantially more concentrated than it was in nature; and second, you’ve given it a function. If it doesn’t work in the diluted form but does work in a concentrated form, you’ve given it a new function. And by both changing its nature and by giving it a new function, you may well have patent …”

If Myriad is taken as a pretext, it is clear from the above exchanges that the position now adopted by the USPTO in the Myriad/Mayo guidelines seems clearly inconsistent with the understanding of the Justices of the Supreme Court.

Judicial exceptions to patent-eligibility, which is defined by statute, should be treated conservatively, not gold plated. The USPTO’s expansive reading of Myriad and Mayo interjects uncertainty and raises significant questions about U.S. patent law as it applied to the biotechnology and pharmaceutical sectors. This will not be good for the U.S. economy or for the many innovators who rely upon patent protection.


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Join the Discussion

3 comments so far.

  • [Avatar for Shoichi]
    April 3, 2014 02:02 am


    Thank you for your nice article. My pharma colleagues are angry at the new guidelines. The value of certain patents that claim naturally occurring products, but so far had been patentable, went down to zero, even if it is, hopefully, temporarily. What is going on at the USPTO?


  • [Avatar for EG]
    March 12, 2014 08:13 am


    Nice article. What you point out about these new USPTO guidelines confirms my initial assessment of them: nothing but trouble. As usual, when Our Judicial Mount Olympus speaks, the USPTO interprets incorrectly what was said, including what was said at oral argument.

  • [Avatar for Paul Cole]
    Paul Cole
    March 10, 2014 07:17 pm

    The following has been sent to Andrew Hirshfeld at USPTO:

    I am writing to draw your attention to recent postings on the patents4life and IPWatchdog blogs concerning the new guidance about the patent-eligibility of purified natural products. In my submission that guidance is plainly and profoundly wrong and inconsistent with case law. You are invited to post a reasoned reply or to reconsider your guidance.

    It will be interesting to see if there is a reply.

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