By Audrey A. Millemann

A patent must sat­­isfy several requirements in order to be valid. One of these is the written description requirement, as set forth in 35 U.S.C. §112, ¶1. That subsection requires that a patent:

”contain a written description if the invention…in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains… to make and use the same…”

The purpose of the written description requirement is to demonstrate that the inventor is in possession of the invention (i.e., actually invented the claimed invention) as of the date the patent application was filed. In Novozymes A/S v. DuPont Nutrition Biosciences APS, 723 F.3d 1336 (Fed. Cir. 2013), the Federal Circuit Court of Appeals held that a specification that is a “mere wish or plan” does not satisfy the written description requirement. The case is a strong reminder to patent applicants and practitioners that the written description requirement is critical.

In 2000, Novozymes filed a provisional patent application for certain enzymes in a class of enzymes called alph-amylases, which break down polysaccharides. Alpha-amylases, like all enzymes, are proteins made up of chains of amino acids. There are approximately 500 amino acids in an alpha-amylase enzyme. Alpha-amylases are typically isolated from specific bacteria.

Novozymes had been working on developing an alpha-amylase enzyme based on a bacterial enzyme, but modified the bacterial enzyme so that it would remain stable under heat and acidic conditions. The 2000 application disclosed a large number of possible variants of the modified bacterial enzyme based on seven possible bacterial parent enzymes, 33 positions on the amino acid chain that could be altered (by deletion, addition, or substitution of an amino acid), at least 40 amino acid mutations at each position, and innumerable combinations of all these variables. The 2000 application contained several examples of possible combinations of these variables, but later research showed that many of these specific variants did not have thermal stability.

In 2001, Novozymes filed its first utility application based on the 2000 provisional application, and elected one species (variant) of the enzyme to be examined. Novozymes also filed a continuation application for another species. No patents issued from these applications.

DuPont started work in 2006 on an alpha-amylase enzyme that was also thermally stable. DuPont used one of the seven bacterial parent enzymes, but not the one that Novozymes had elected. DuPont tested 1500 variants and identified the variant that was the most thermally stable. DuPont filed a patent application for this variant in 2008. The patent issued in 2009. 

Shortly afterwards, Novozymes became aware of DuPont’s patent. Novozymes then filed a new continuation application in 2009 that claimed priority to its 2000 provisional application and contained essentially the same specification. In 2010, the application issued as U.S. patent no. 7,173,723.

On the day the ‘723 patent issued, Novozymes sued DuPont for patent infringement in the Western District of Wisconsin. DuPont filed a counterclaim for invalidity of the patent based, among other things, on lack of written description. The district court granted summary judgment for Novozymes on infringement. The case was tried, and the jury found that the ‘723 patent was not invalid, and awarded Novozymes over $18 million in damages for DuPont’s infringement.

DuPont moved for judgment as a matter of law. The court granted the motion, holding that the ‘723 patent’s claims were invalid for failure to satisfy the written description requirement of §112. 

The district court held that the ‘723 patent’s specification (the same as the 2000 patent application’s specification) was not adequate to support the claims of the ‘723 patent. The court found that the 2000 specification covered “a potentially enormous number of alpha-amylase variants” because of the vast number of possible combinations of the seven parent enzymes, the 33 amino acid positions for mutation, the many mutations possible at each position, and the many combinations of mutations. The 2000 specification did not specifically mention the variants that were later claimed in the ‘723 patent. As the district court stated, “the concern is that a patentee may attempt to use later filed claims, relying on more recently discovered data, to expand the scope of his invention or complete an idea.”

In essence, although the 2000 specification disclosed thousands of enzymes, it did not identify which variant worked, as the claims required. The district court noted that it was DuPont who figured out which variant worked: “[t]he actual inventive work of producing a [working variant] was left for subsequent inventors to complete.”

Novozymes appealed. The Federal Circuit Court of Appeals affirmed the decision.

The court stated: “The specification must describe an invention understandable to [a] skilled artisan and show that the inventor actually invented the invention claimed…A ‘mere wish or plan’ for obtaining the claimed invention does not satisfy the written description requirement.”

Novozymes argued that a person skilled in the art of recombinant enzyme technology was highly skilled and would have understood the invention given that the important piece of information was the position of the mutation, not the specific mutation itself. Novozymes contended that the 2000 specification did disclose the particular variant claimed in the ‘723 patent because it disclosed the parent enzyme, the position of the substitution, and the thermal stability of the enzyme. According to Novozymes, it was irrelevant that the 2000 specification disclosed these attributes not as a single enzyme, but separately as possible variables among thousands of other variables, most of which did not work.

DuPont characterized Novozymes’ 2000 specification as a research plan, theory, or “laundry list” of possible enzymes; it was an “invitation to experiment” that did not yield a functional enzyme. DuPont argued that the written description requirement is not satisfied by claims to a research plan, and when a patent application adds new claims to a previously filed application, there should be a clear description of the claimed invention in the original specification.

The Court of Appeals held that the 2000 specification was “only generalized guidance listing several variables that might, in some combination, lead to a useful result.” Nothing in the 2000 specification showed that Novozymes possessed the enzyme it claimed in the patent. 

The court explained that claims are often held invalid when the specification describes a broad genus with many possible species, but the claims are directed to a single species in the genus. The court agreed with Novozymes that the 2000 specification separately disclosed each of the limitations of the claims, but held that it did not anywhere disclose a specific variant that had these particular limitations and functioned as a thermally stable enzyme.

The court found that Novozymes’ failure to disclose, in its original specification, the variant it later claimed was further evidence that it had not possessed that variant at the time it filed the 2000 application. It was DuPont who tested hundreds of variants and found the one later claimed by Novozymes. The court reiterated that:

“A patent however, is not a reward for the search, but compensation for it successful conclusion.”

This case is a reminder that a patent is a grant of a property right, and the property is the invention. If the patent does not describe the invention, then it cannot identify the property to be protected, and there can be no patent.  Thus if, §112’s written description requirement is not satisfied, the patent can (and likely will) be invalidated.