Federal Circuit cites KSR, but not for the new obviousness standardMay 3, 2007

In a nonprecedential opinion released today, the Federal Circuit cited the Supreme Court's Monday decision in KSR for the first time. Unfortunately for inventors and practitioners looking for guidance under the new standard for obviousness laid out in KSR, the reference had nothing to do with the obviousness standard, just that obviousness is a question of law based on underlying factual information.

More details of the case after the jump.

Syngenta Seeds, Inc. brought suit against Monsanto and Dow Agrosciences for infringement of three patents (the '865, '185, and '100 patents) relating to use of transgenic crops incorporating insecticidal proteins based on proteins produced by the Bacillus thuringiensis (Bt) bacteria. These proteins are useful for producing crops that are resistant to certain agricultural pests.

In the native Bt gene at issue, about 38% of the nucleotides are G-C pairs. However, corn plants tend to have codons rich in G-C pairs, so Syngenta sought to design a Bt gene with more G-C pairs so that it might be expressed more in corn. Eventually Syngenta produced a truncated Bt gene with 65% G-C nucleotides. The pertinent claims to the case in the '865 patent claim transgenic corn where the coding sequence has a G-C content of at least about 60%. The pertinent claims in the other two patents relate to plants that produce the Bt protein, but also require particular codons (Murray maize-preferred codons) so the sequence also contains at least about 60% G-C nucleotides.

The district court construed the claims of the '185 and '100 patents to require that the change from 38% G-C to 60% G-C be attributable solely to the G-C nucleotides in the Murray maize-preferred codons in the sequence. Syngenta conceded that, under this construction, these patents were not infringed, and the Federal Circuit affirmed both the claim construction and the concomitant noninfringement finding, in part because Syngenta's claim construction position on appeal was not advanced at the district court, and the court therefore found it had waived its right to argue for a contrary construction. A jury found the asserted claims of the '865 patent infringed but obvious and lacking adequate written description.

With regard to obviousness, the main prior art reference described a method for improving Bt expression in plant genes, particularly that while Bt genes typically have high A-T content, plants generally have a higher G-C content, and thus selecting codons higher in G-C content would likely increase expression of the Bt proteins.

Syngenta argued that while this general idea may have been obvious, the idea to modify the sequence to increase the G-C content to over 60% would not have been obvious. The defendant's expert testified that a synthetic Bt gene with a coding region consisting entirely of plant-preferred codons would have a G-C content over 60%. The court held that the jury was free to credit this testimony and hold that, in light of the prior art reference described above, the asserted claims were obvious to one of ordinary skill in the art.

Syngenta made further arguments based on the facts of the prior art reference and what one of ordinary skill in the art would be motivated to do, but ultimately the court found them each unpersuasive.

As far as the KSR cite, here is the full quote from the opinion:

While “the ultimate judgment of obviousness is a legal determination,” KSR Int’l Co. v. Teleflex Inc., No. 04-1350, slip op. at 23 (U.S. Apr. 30, 2007), that determination is necessarily based on underlying factual inquiries, see Winner Int’l Royalty Corp. v. Wang, 202 F.3d 1340, 1348 (Fed. Cir. 2000).

To read the full decision in Syngenta Seeds, Inc. v. Monsanto Co., click here.

← Return to Filewrapper

Stay in Touch

Receive the latest news and updates from us and our attorneys.

Sign Up