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The Test for Obviousness Does Not Require an Explicit Suggestion in a Particular Reference to Combine References

October 03, 2006

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Last Month at the Federal Circuit - November 2006

Judges: Michel (author), Rader, Schall (concurring)

[Appealed from: D.S.C., Judge Catoe]

In DyStar Textilfarben GmbH & Co. Deutschland KG v. C.H. Patrick Co., No. 06-1088 (Fed. Cir. Oct. 3, 2006), the Federal Circuit reversed the district court’s denial of Appellants’ motion for JMOL of invalidity of claims 1-4 of U.S. Patent No. 5,586,992 (“the ’992 patent”) for obviousness.

The ’992 patent discloses a process for dyeing textile materials with catalytically hydrogenated leuco indigo. Traditionally, the process for dyeing textile materials with catalytically hydrogenated leuco indigo involves six steps: “(1) reducing indigo to its leuco form in solution; (2) stabilizing the leuco indigo solution, usually in paste or powder form; (3) creating a preparation tank in which the dried leuco indigo is re-converted to solution form; (4) adding the solution to the dyebath; (5) dipping; and (6) skying.” Slip op. at 4.

The ’992 patent improved this process by eliminating the second and third steps. In other words, it permitted a dyer to pour prereduced indigo solution directly into a dyebath and commence dyeing immediately. DyStar Textilfarben GmbH & Co. Deutschland KG (“DyStar”) sued C.H. Patrick Co. and Bann Quimica Ltda. (collectively “Bann”), alleging direct, contributory, and induced infringement of the ’992 patent. The jury found that Bann infringed the ’992 patent and declined to hold the patent invalid for lack of enablement, anticipation, or obviousness. Bann moved for JMOL, or alternatively a new trial, on the issue of invalidity of the ’992 patent. The district court denied Bann’s motion without opinion, stating that the jury’s verdict was reasonable and supported by evidence in the record.

On appeal, the Federal Circuit noted that the law of the regional circuit applies when reviewing motions for JMOL and motions for a new trial and applied Fourth Circuit law to those issues. The Court, however, reviewed the jury’s obviousness ruling under its own law, applying the four Graham factors. The Court stated that it must consider whether “a person of ordinary skill in the art would have been motivated to combine the prior art to achieve the claimed invention and whether there would have been a reasonable expectation of success in doing so.” Id. at 6. The Federal Circuit specifically noted that it is important to distinguish between the references sought to be combined and “the prior art” when considering what the prior art teaches. According to the Court, the “prior art” is broader, encompassing textbooks, treatises, and basic principles unlikely to be restated in cited references, and the motivation to combine the cited reference may be found in the prior art as a whole.

Because the parties’ dispute centered around the relevance of the cited prior art, and therefore the level of ordinary skill in the art, the Federal Circuit began with the third Graham factor. The Court agreed with DyStar that the jury accepted its view that a person of ordinary skill in the art had no knowledge of chemistry and must have found the cited prior art in neither the relevant art nor the analogous arts. Nevertheless, the Court concluded that substantial evidence did not support the jury’s findings. The Court explained that the technical problem the ’992 patent sought to solve was precisely the same problem the cited references sought to solve, i.e., an improved process for dyeing textiles with indigo. Moreover, the Court concluded that practicing the ’992 patent required a “higher-level perspective,” not merely “flipping the switch.” Thus, one of ordinary skill would have knowledge of chemistry and systems engineering. Accordingly, the Court concluded that the jury’s decision to disregard the cited prior art was not supported by substantial evidence.

Turning to the first Graham factor, scope and content of the prior art, the Federal Circuit considered “[w]hat the prior art teaches, whether it teaches away from the claimed invention, and whether it motivates a combination of teachings from different references.” Id. at 11-12. The Court focused on art relating to the indigo dyeing process as a whole and rejected DyStar’s argument that the cited references were nonanalogous art because they reduced indigo by different methods. Because reduced indigo by any reduction method had been used in the indigo dyeing process, prior art involving indigo reduction by other methods constituted analogous art. Thus, the Court concluded, the cited art recited all the limitations of claim 1 of the ’992 patent.

The Federal Circuit next considered whether there was motivation to combine the cited prior art. The Court rejected DyStar’s argument that Federal Circuit precedent required the cited references themselves to explicitly contain a suggestion, teaching, or motivation to combine the art. The Federal Circuit explained that DyStar, as well as various commentators, had misread the Court’s opinions and mischaracterized its suggestion test. As the Court expounded, the suggestion test is not a rigid and categorical test that requires an explicit teaching to combine references be found in a particular prior art reference. Rather, it “not only permits, but requires, consideration of common knowledge and common sense.” Id. at 20 (emphasis in original). The Court further explained that when “no prior art reference contains an express suggestion to combine references, then the level of ordinary skill will often predetermine whether an implicit suggestion exists.” Id. at 26. The inquiry in such a situation would be “whether the ordinary artisan possesses knowledge and skills rendering him capable of combining the prior art references.” Id. at 21 (emphasis in original).

Having determined that one of ordinary skill in this case is a dye process engineer who would possess knowledge of chemistry and systems engineering, and that the asserted innovation of the ’992 patent is merely exploitation of the well-known principle of vacuum packaging, the Court concluded that the invention is the work of a skilled chemist, not an inventor. The Court also held that certain secondary considerations of nonobviousness were insufficient to overcome the Court’s conclusion that claim 1 was obvious. The Court also held claims 2-4 invalid for obviousness as they do not recite a nonobvious invention beyond claim 1.