Federal Circuit Confirms Invalidity for Overbroad Written DescriptionJuly 23, 2013

Novozymes v. DuPont Nutrition Biosciences involved patent 7,713,723 directed toward recombinant Bacillus alpha-amylase enzymes engineered to have enhanced acid tolerance and heat tolerance. The patent owner, Plaintiffs-Appellants Novozymes, sued DuPont for infringement. DuPont defended on grounds of non-infringement and invalidity and countersued for a declaratory judgment that the '723 patent was invalid for failing to satisfying the enablement and written description requirements of 35 U.S.C. § 112.

Novozymes had identified thirty-three Bacillus alpha-amylase amino acid positions as targets for mutagenesis. Novozymes filed a patent in 2000 for these variants with enhanced stability, specifying that any of the positions could be altered by deletion, addition, or substitution to create variants with improved stability. Ultimately, the application included a wide range of potential variants without identifying any of the mutations as being preferred. Instead, it only offered two examples including one for the S239W mutation, which was found to be inoperable.

In 2006, DuPont began work on similar alpha-amylase variants and came up with mutations which overlapped with six of the amino acid positions identified in Novozymes' 2000 application. This included position 239, but the Novozymes application did not disclose the particular substation used by DuPont, S239Q. DuPont obtained a patent (7,541,026) on the variant in 2009.

Shortly thereafter, Novozymes filed a continuation application with claims drawn specifically to variants substituted at position 239, which issued in 2009. The specification of the continuation was essentially the same as the 2000 application. The day the patent issued, Novozymes sued DuPont for infringement.

The main issue in this case was whether Novozymes satisfied the written description requirement for the claims at issue. The Court quoted Ariad, which required that the written description "clearly allow person of ordinary skill in the art to recognize that [the invention] invented what is claimed." The Court also noted that often in cases where a patent's written description disclosed an invention in terms of a broad genus but the claims were directed toward a specific species, there must be some indication to guide a reader towards preferred possibilities out of the group.

Novozyme cited Union Oil, a Federal Circuit case involving a gasoline composition claimed in terms of various chemical and physical properties instead of describing the individual components. In that case it was decided that anyone having ordinary skill in the art would have produced a composition with those properties which performed the claimed invention and so the written description showed that the inventors possessed the claimed invention at the time of filing.

In contrast, while Novozyme's specification included a number of possible variants and offered some limitations, it did not point out any particular characteristics which would guide a reader to the claimed variant. The Court determined that the 2000 application did not disclose any variant that satisfied the claims and the specification failed to show that Novozymes possessed such a variant at the time of filing. The Court ultimately held that no reasonable jury could find that the claims of the '723 patent met the written description requirement of 35 U.S.C. § 112 and the district court properly invalidated the claims.

Chief Judge Radar dissented, stating that he would reverse the grant of judgment as a matter of law and reinstate the jury's verdict. He noted that the jury had found that a skilled artisan would know how to arrive at the claimed invention by substituting amino acids. Their decision was based on expert testimony which suggested that finding the claimed variants based on the specification was routine and would only take a week if you had a team of ten scientists making and testing all nineteen amino acid substitutions at each of the thirty-three amino acid positions.

Given the Federal Circuit's recent decision in Wyeth v. Abbott Laboratories, it seems that providing a large number of options of a genus in a patent description could lead to trouble, even if one with skill in the art could arrive at the claimed invention with routine experimentation. The specification needs to provide some guidance to narrow down the possibilities and enable the reader to arrive at the claimed species without undue experimentation.

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