Contact the author: Andrew Berks
This is a significant decision that extends the Federal Circuit’s holdings on written description from Ariad Pharms., Inc. v. Eli Lilly Co., 598 F.3d 1336 (Fed. Cir. 2010) (en banc), and has important lessons for patent applicants seeking to obtain functional claims, and for patent challengers facing blocking functional claims.
Abbvie (an Abbott spinoff starting in 2013) owns US Patents 6914128 and 7504485. These patents are directed to humanized antibodies that bind to and neutralize the activity of human interleukin 12 (IL-12). The over-production of IL-12 is a cause of psoriasis and rheumatoid arthritis. Slip op. at 5–6. Abbvie’s antibodies are based on a lead called “Joe-9,” that was developed through phage display technology. Its not mentioned in the opinion if Abbvie has an approved product based on the patented technology.
Centocor developed an anti-IL-12 antibody called “Stelara®” using transgenic mouse technology, approved by the FDA in 2009. Centocor filed a patent application, 10/912994 on its product, which apparently has not issued. The key point with Stelara is that it is structurally substantially different than the Joe-9 derived antibodies from Abbvie.
Five claims were at issue, which each define the claimed antibodies by their function rather than their structure. The opinion cited claim 29 of the ‘128 patent as representative. Claim 29 recites an isolated human antibody that binds to IL-12 with a koff rate constant of 1×10-2 s-1 or less, as determined by surface plasmon resonance.
Centocor provoked an interference with Abbvie in 2007 which included arguments by Centocor that the Abbvie patents were invalid as obviousness. On August 6, 2009 the BPAI (predecessor to the PTAB) held in favor of Abbvie, that it was the senior party and that the Abbvie patents were not obvious.
So Abbvie promptly filed the instant action in the district of Massachusetts, alleging that Centocor was infringing the ‘128 and ‘485 patents. Centocor also appealed the Board’s decision under 35 USC § 146 in the Dist. Ct for the District of Columbia seeking a declaration of noninfringement and invalidity of the ‘128 and ‘485 patents. The two actions were consolidated in the Massachusetts court (Judge F. Dennis Saylor IV)
Following claim construction, the district court granted summary judgment to Abbvie that Centocor infringed the five asserted claims. However, on the issue of validity (written description, enablement, obviousness, and anticipation) the case was submitted to a jury, which determined that all the asserted claims were invalid on written description, enablement, and obviousness grounds. The jury found the claims invalid under the clear and convincing evidence standard. Since the § 146 action required a lower standard of proof, the court also entered judgment in Centocor’s favor on the § 146 claims. The court denied Abbvie’s motion for JMOL on the written description, enablement, and obviousness holdings.
Abbvie appealed, and the Federal Circuit panel (Lourie, O’Malley, and Chen, opinion by Lourie) upheld the district court in all respects. As a preliminary matter, footnote 5 in the opinion notes that Abbvie did not substantially challenge the obviousness finding at the district court, so the court notes that Abbvie’s patents are invalid for that reason. (This is presumably because one of the other issues here was whether the jury was properly instructed on the obviousness question.) However, the court considered the written description question because the Federal Circuit is an “inferior court” so a “higher authority” (i.e., the Supreme Court) can find error on other bases in a more limited review. Since the Federal Circuit is not a court of last resort, its decision to decide a case on one of two alternative grounds does not strip the court of its power to decide the second question. Cardinal Chem. Co. v. Morton Int’l, Inc., 508 U.S. 83, 97–98 (1993).
The significance of this opinion is the holding that a genus described in functional language fails to meet the written description requirement where the genus exceeds the scope of the underlying structures disclosed in the specification. “The essence of the written description requirement” is that as part of the bargain with the public, a patent applicant must describe an invention so that the public will know what the invention is, and can show that the inventor was in possession of the claimed invention. Slip op. at 20–21. “Possession” is shown by evidence in the disclosure (Ariad, 598 F.3d at 1351). When a patent claims a genus using functional language, the specification must demonstrate the applicant has invented species sufficient to support a claim to the functionally-defined genus. Slip op. at 22. The panel finds here that Abbvie failed to do that.
The panel analogizes this situation to a plot of land, where the property description is only to a corner of the plot, which is not a sufficient description to “distinctly circumscribe the outer boundaries” of the invention. Moreover, with the written description of a genus, merely drawing a fence around the invention isn’t good enough. A patent applicant has to also describe representative species encompassing the breadth of the genus. Otherwise the patent applicant has only described a research plan, leaving it to others to explore the unknown contours of the claimed genus. Slip op. at 23.
Here, despite the functional claiming that does not recite specific structural features, the panel limits Abbvie’s invention to a narrow set of antibodies derived from Joe-9 (“the described species are all of the similar type and do not qualitatively represent other types of antibodies encompassed by the genus”). Slip op at 24-25. However, the functional features are much broader and encompass Stelara.
This opinion takes a very harsh view of functional claiming: “the patents must at least describe some species representative of [the alleged infringing product].” Slip op. at 25. Thus, functional claims must have an underlying structural description that embraces the structural diversity of the claimed genus. Id. The opinion cautions that functional claims are vulnerable to written description attack unless the subject matter involves a “reasonable structure-function correlation.” Slip op. at 26. But in unpredictable technology fields (such as antibody function) this is difficult (and in the apparent view of the panel, unlikely to result in a valid claim). Moreover, The ‘128 and ‘485 patents do not describe any common features of the claimed antibodies. The claims attempt encompass any human antibody that achieves a desired result, including Stelara which is structurally very different from Abbvie’s Joe-9 –derived antibodies. Accordingly, the claims are invalid for lack of written description.
There were also procedural issues addressed in the case, pertaining to collateral estoppel over whether the BPAI decision in the interference proceeding was an actual litigation with a binding and final judgment with preclusive effect. The panel said “no,” and this question was also the subject of a concurring opinion by Judge O’Malley (who otherwise agreed with the “thoughtful” written description opinion).
Lessons: After this case, functional claiming will likely be treated with great caution by patent examiners and the courts. Patent applicants seeking to obtain functional claims should be careful to disclose a full range of underlying structural features that give rise to the functional features. The danger for applicants seeking to obtain functional claims is that someone will come along with a new structure (not contemplated by the original inventor) that exhibits the claimed function, and the patent could be lost. This case further underscores the policy preference for patents covering structural features of inventions, not functional features.
For patent challengers, potential new avenues of attack on functional claims are opened up, so that by showing a scope of a functional genus that exceeds the scope of the disclosure, a patent can be invalidated.
Link to this post: http://wp.me/p3y1Ss-ey