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Court Finds Patent Claim Invalid For Lack Of An Adequate Written Description

By Karen E. Keller, Andrew A. Lundgren et al.

Crown Packaging Tech., Inc. v. Rexam Beverage Can Co., C.A. No. 05-608-MPT (D. Del. Jan. 22, 2007)

Rexam moved for partial summary judgment of invalidity and noninfringement. The Court granted both motions in part. As to noninfringement, the Court held that Rexam did not infringe the claim at issue under the doctrine of equivalants, granting Rexam’s noninfringement summary judgment motion. Other noninfringement arguments were denied as moot. As to invalidity, although Rexam asserted several bases for invalidity (including § 102, § 103, lack of adequate written description, and indefiniteness), the Court granted summary judgment only on inadequate written description grounds, mooting the other invalidity bases.

Most of the opinion dealt with the inadequate written description issue, and I will spend the remainder of this post on that issue. Rexam argued that the claim at issue failed to comply with § 112, para. 1 because it did not include the “annular reinforcing bead” limitation contained in the patent’s other asserted claims. Section 112, para. 1 requires the specification to “describe the invention sufficiently to convey to a person of skill in the art that the patentee had possession of the claimed invention at the time of the application.” Lizardtech v. Regents of Univ. of Cal., 424 F.3d 1336, 1345 (Fed. Cir. 2005). Based on intrinsic evidence, inventor testimony, and expert testimony, the Court found that “[n]owhere is there an indication that the inventors possessed a can end having the other elements of claim 34 of the ‘875 patent [claim at issue] without also having an annular reinforcing bead.” Op. at 13. Thus, the Court held that the specification did not support the broader claim without the “annular reinforcing bead” limitation, and the claim was therefore invalid for failure to comply with the written description requirement.
Let’s pause for a moment and consider the analytical framework of this decision. I submit that this decision is correct under Federal Circuit precedent, but this issue – claims broader than the specification – fits more neatly under either the noninfringement or claim scope inquiries. Under the Gentry Gallery decision and its progeny, the Federal Circuit usually (depending on the panel) holds that a feature described in a patent as “essential” or “critical” to the invention must be present in that patent’s claims. If such a feature is not present, the claim is invalid for lack of an adequate written description. That is, a claim is invalid if the inventor did not possess the claimed invention, which must contain the essential element, at the time of the application. The Court here, however, also correctly points out that an explicit statement of limitation is not required for the specification to limit the claims. See Op. at fn 46. (Patent prosecutors, of course, almost never describe a feature as the “invention” or “essential to the invention” for just this reason, as well as other reasons related to claim interpretation.) In this case, the patent specification did not describe the annular bead limitation as “essential” or “critical” to the invention; the specification merely failed to mention an embodiment that did not contain the annular bead. In fact, even the abstract of the patent at issue referenced the annular bead limitation. Op. at 6.

Under these circumstances, it seems fair to limit the patentee to embodiments containing the annular bead. After all, even the patent abstract contains the annular bead limitation. It seems strange to me, though, to analyze this issue as one of invalidity for lack of a written description. Before Gentry Gallery, Lizardtech (Op at fn 20), Enzo, and other similar cases, no one would have argued that this issue, claims drafted more broadly than the preferred embodiments, was an inadequate written description problem. You might have argued that the claim scope should be narrowed so as not to include the broader interpretation (claim scope) or that the reverse doctrine of equivalents applied such that the accused product would not infringe (noninfringement). Now, however, after Gentry Gallery and cases like it, we find ourselves in a situation where the Court is forced to determine what the inventor thought of as “essential” or “critical” features to his/her invention at the time of filing, and then strike any claims that do not include these features. It seems to me that this problem would be better dealt with either during the claim construction phase (Limit the scope of the claims based on the specification, being careful not import a limitation from the specification into the claims. This would allow the claims to be interpreted so as to preserve their validity – a canon of claim construction) or during the infringement determination (The reverse doctrine of equivalents, if it still exists, would prevent infringement where the claims are broader than the specification).

What do you think about accused infringers using the written description requirement as a sword in this manner? Should the Federal Circuit overrule Gentry Gallery? Or resurrect the reverse doctrine of equivalents? Please post your comments.

Full post as published by Delaware IP Law Blog on January 28, 2008 (boomark / email).