A decision issued by the Federal Circuit April 29, 2011 offers a lesson for patent prosecutors to talk to each named inventor about what they consider to be the best way of practicing their invention. Though anti-intuitive, it is possible to have multiple best modes. In Wellman, Inc. v. Eastman Chemical Co. (Fed. Cir. 2011), the Federal Circuit has held that the best mode requirement of 35 U.S.C §112 applies to each named inventor (as opposed the inventors collectively). The statutory language on this point is less then clear as §112 requires disclosure of the best mode “contemplated by the inventor.” The issue is whether “the inventor” refers to a single best mode contemplated by all the named inventors or whether “the inventor” refers to each and every inventor, thereby allowing for the possibility of multiple best modes for a patent. In addition, the term “best mode” suggests only one mode per patent. Up to this point, Federal Circuit precedent was also unclear on the issue. The only Federal Circuit decision addressing this issue supported the latter position, but did so in dicta in a footnote. See Pannu v. Iolab Corp., 155 F.3d 1344, 1351 n.5 (Fed. Cir. 1998). However, multiple Federal Circuit decisions have used loose language that supports the former position, though those decisions weren’t presented squarely with the issue.
In Eastman, the Federal Circuit adopted the dicta in Pannu and held that “best mode issues can arise if any inventor fails to disclose the best mode known to him or her.” In Eastman, one of the inventors had testified that a certain recipe for PET resins was, in his mind, the best resin available at the time the application was filed. The patentees, however, choose to maintain that recipe as a trade secret rather than specifically disclose it in the patent application. Instead, the patent “hides” the best mode by disclosing broad ranges for certain elements that technically encompass the best mode recipe, but which failed to enable a person of ordinary skill to practice the best mode. Significantly, the patent actually “leads away” from one critical element through statements about “typical” and “preferred” properties within a range that the actual best mode compound does not have.
The lesson of Eastman for patent prosecutors is to talk to each named inventor about what they consider to be the best way of practicing their invention. Though anti-intuitive, it is possible to have multiple best modes. Further, if you’re dealing with a chemical patent, it’s much safer to directly disclose the actual best mode, but if you opt to use “ranges” to make the required disclosure, the best mode must be enabled.
Two final comments. First, Chief Judge Radar found that “Wellman intentionally concealed the best mode.” Perhaps we will find out if intentional concealment of the best mode is a sufficient predicate for an inequitable conduct defense. Second, Patent Reform (addressed in this post), removes the best mode requirement from 35 U.S.C § 112. So, it’s possible that this may be the last significant best mode decision.