A Generic Disclosure Does Not Support Claims to Individual Species Re: Protein Variants and Litigation
Addressing the issue of written description as it relates to a genus and related species, the U.S. Court of Appeals for the Federal Circuit upheld a district court’s post-trial grant of a motion for judgment as a matter of law that claims were invalid for lack of written description, finding that a description of a genus does not provide sufficient written description of claims to particular undisclosed species. Novozymes A/S v. DuPont Nutrition Biosciences APS, Case No. 12-1433 (Fed. Cir., July 22, 2013) (Schall, J.) (Rader, J., dissenting).
Plaintiff Novozymes filed a patent application in 2000 describing improved variants of alpha-amylase proteins used in commercial-scale ethanol production. The disclosure identified 33 specific amino acid positions (out of more than 500 possible positions) that can be changed (“mutated”) to yield protein variants that are more thermostable (i.e., heat-resistant). The disclosure further describes that each target position can be mutated in one of about 40 different ways and included “pages” of specific, exemplary mutations. The examples presented data for a few such variant proteins that displayed improved thermostability, but post-filing date experiments revealed that some of the 33 positions did not yield any variants with improved thermostability (including a tryptophan mutation at position 239, denoted “S293W”).
After the Novozymes application was filed (in 2000), DuPont developed an alpha-amylase variant protein with a glutamine mutation at position 239 (denoted “S239Q”). In response, Novozymes filed a continuation application and claimed alpha-amylase variant proteins containing a mutation at position 239 and having improved thermostability. After trial Novozymes sued DuPont on the resulting patent, the district court judge granted DuPont’s motion for judgment as a matter of law (JMOL) and overturned the jury’s special verdict that the Novozymes patent was not invalid for lack of written description. DuPont appealed.
The Federal Circuit upheld the district court’s determination of invalidity for lack of written description, centering its analysis on the fact that the patent disclosure did not explicitly describe any specific variants falling within the scope of the claims. The Court noted that that, “[w]hile the 2000 application provides formal textual support for each individual limitation recited in the claims of the … patent, it nowhere describes the actual functioning, thermostable alpha-amylase variants that those limitations together define.” The Court further found that “one searches the 2000 application in vain for the disclosure of even a single species that falls within the claims or for any ‘blaze marks’ that would lead an ordinarily skilled investigator toward such a species among a slew of competing possibilities.” Indeed, although the specification described a variant with a mutation at position 239 (i.e., the S239W variant), this variant did not display the improved thermostability as required by the claims. The Court concluded that since a person of ordinary skill in the art “could not know which, if any, individual substitutions . . . would yield increased thermostability without actually making and testing the variants,” Novozymes was not in possession of such variants.
The Federal Circuit cautioned against conflating the distinct requirements of written description and enablement, noting that the relevant question is not whether a person of ordinary skill in the art would have been enabled to identify specific variants within the scope of the claims, but instead, whether the specification actually discloses those variants to a person of skill in the art. To demonstrate actual possession of the claimed variants, “Novozymes [needed] to confirm its predictions by actually making and testing individual variants or at least identifying subclasses of variants that could be expected to possess the claimed properties.”
In dissent, Chief Judge Rader argued that substantial evidence (e.g., expert testimony, visual aids, and publications over an eight-day trial, along with use of a special verdict form) supported the jury’s verdict and that it should be reinstated. Chief Judge Rader noted that the jury heard expert testimony that “finding the position where you can make a beneficial mutation is, in fact, the inventive step” and that, once those positions are known, only a week’s worth of well-known, routine experimentation would be required to make and test the substitutions. He further noted that “[t]his court might also have credited the patentee with reducing the original 500 total amino acid positions down to a mere thirty-three.”