United States: In Claim Construction, Grammar-Based Argument Did Not Overcome Clear Written Description

In 3M Innovative Properties Co. v. Tredegar Corp., No. 12-1241 (Fed. Cir. Aug. 6, 2013), the Federal Circuit affirmed the district court's construction of the claim terms "continuous contact" and "continuous microtextured skin layer over substantially the entire laminate," but clarified the scope of those terms. The Court reversed the district court's construction of the claim terms "preferential activation zone" and "ribbon," providing new constructions, vacated the district court's constructions, and remanded the case for further proceedings.

3M Innovative Properties Company ("3M") and Tredegar Corporation ("Tredegar") compete in the elastomeric industry, which includes diapers. 3M sued Tredegar for infringing four patents relating to stretchable films or laminates that allow products to expand to fit around the person wearing them. Two of the asserted patents are directed to laminates with "continuous" microtexturing over the laminate's skin layer, and the other two are directed to laminates in which the elastic or stretching portions of the skin layer are limited to selected areas identified as "preferential activation zones." The laminates in all four patents have an inelastic skin layer adhered to both sides of an elastic core. When the laminate is stretched, folds form where the skin meets the core, giving rise to a microtextured surface. The district court construed thirty terms in the four patents, and the parties stipulated to noninfringement. 3M appealed the district court's construction of four of the thirty terms.

On appeal, the Federal Circuit first addressed the construction of the terms "continuous contact" and "substantially continuous contact," which the parties agreed should be construed identically. The district court construed the terms to mean "full surface contact" in reference to the contact between the core and the folds of the microtextured skin. The parties, however, disputed the meaning of the definition "full surface contact" based on three figures in the patent. The figures depicted "full contact," where the core material fills the skin folds; "cohesive failure," where the core material fills the skin folds, but cracked internally under the folds; and "adhesive failure," where the extensive folding of the skin layer allows for only sporadic contact with the core material. 3M argued that cohesive failure mode is "continuous" or "substantially continuous contact" because the skin and core layers remain joined without interruption, despite cracks pervading in the core. Tredegar argued that cohesive failure mode is not "continuous contact," because the applicant amended its claims to distinguish between full contact and cohesive failure. The district court adopted Tredegar's interpretation of "full surface contact" as limited to the full contact mode.

Starting with the claim language, the Federal Circuit noted that the term "continuous contact" as used in the claims does not suggest whether the patentee intended to include cohesive failure mode, providing no basis to suppose that the claim term applies only to the full contact mode. The Court thus agreed with 3M that the plain and ordinary meaning of the claim term supported a broad claim scope, including cohesive failure situations. The Court also found that the written description, which described cohesive failure as "a variation" of full contact, supported a broader scope and that neither the written description nor the prosecution history provided a clear disavowal of the cohesive failure mode. Ultimately, the Federal Circuit affirmed the district court's construction of "continuous contact" and "substantially continuous contact" as "full surface contact," but clarified the definition of "full surface contact" as including cohesive failure.

The Court next addressed the term "continuous microtexturized skin layer over substantially the entire laminate." The district court concluded that the term required the microtexturizing and skin layer to be "continuous" across "substantially the entire surface of the laminate," but qualified its construction by acknowledging that the microtexturing is "substantially uniform over the elastomeric laminate surface." Slip op. at 18-19 (citations omitted). The parties disputed the extent of the microtexturing on the skin of the laminate, with 3M asserting that at least one microtexturized region was required and Tredegar asserting that the laminate as a whole was required to develop microtexturing. The Court found that the intrinsic and extrinsic references supported the middle path identified by the district court.

The Court rejected 3M's reliance on The Chicago Manual of Style as demonstrating that the adjective "continuous" only modified the term "skin layer," not the term "microtexturing." The Court stated that while 3M's grammatical arguments "may be beneficial, for purposes of litigation, . . . [its] cases do not indulge hindsight." Id. at 21. The Court stated, "We are satisfied—based on the clear indications in the written description—that a person of ordinary skill would understand that when the laminate is stretched to the point of deformation, it is substantially the entire skin layer that develops substantially uniform microtexturing." Id.

The Court next addressed the term "preferential activation zone." The district court construed the term as "identifiable predetermined areas of the laminate that are inelastic and, when the laminate is stretched as a whole, will elongate before or to a greater extent than adjacent areas." Id. at 23 (citation omitted). The parties disputed whether the intrinsic evidence supported construing the zones as "predetermined" and "identifiable," and how a "preferential activation zone" is formed. The Court agreed with 3M that the district court's construction improperly read "predetermined" and "identifiable" into the claims. It noted that because one of skill in the art would be informed by the claim disclosures, it was unnecessary to limit the plain language of the claims based on unclear statements in the specification and prosecution history. The Court also found that the "preferential activation zone" could be created in a single step, relying on the statements of the patentee rather than those of the examiner. Because the Court found that the district court had inappropriately limited the meaning of the term, it reversed the district court's construction and clarified the proper interpretation as "selected area[s] of the multi-layer laminate which, when stretched will elongate to form an elastic zone before or to a greater extent than other areas of the laminate." Id. at 30 (alteration in original).

Finally, the Court considered the term "ribbon." It noted that while the claims describe the "ribbon" in terms of color and texture, the words of the claim are silent as to the size or dimensions of the claimed ribbon. The district court construed "ribbon" to mean "a strip of film having a width of no more than one inch." Id. at 31 (citation omitted). The Federal Circuit found that it was against established principles of claim construction to impose an artificial one-inch width requirement not found in the intrinsic record. The Court thus reversed the district court's construction and construed the term to simply mean a "strip of film." Id. at 32.

In a concurring opinion, Judge Plager stated that "there is considerable evidence of a failure by the claim drafters to be clear and precise, and, beyond that, of a shortcoming in the patent examination process that permits claims to be so drafted." Plager Concurrence at 2. Judge Plager opined that ambiguity is sometimes the result of sloppy drafting and sometimes it seeks to leave room to later argue for a broad interpretation to capture later-developed competition. Judge Plager suggested that patents with ambiguous terms may deserve to have the ambiguity construed against the draftsman. According to Judge Plager, that approach would require applicants to draft clear claims, using simple, direct sentences, proper grammar, and definitions in the written description where appropriate. While it would require a greater investment of resources up front, it would reduce wasteful and unnecessary litigation.

Judge O'Malley also filed a separate opinion, concurring-in-part and dissenting-in-part. Judge O'Malley agreed with the majority as to three of the four terms, but dissented with regard to the term "continuous microtexturized skin layer." According to Judge O'Malley, the claim language does not exclude a skin layer where the extent of the microtexturing is anything other than "continuous" over the entire surface. In her opinion, the term is best interpreted as a skin layer that is continuous, microtextured, and extends over substantially the entire laminate. Finding the claim language imposed no clear exclusion of skin layers with intermittent areas of microtexturing and no clear disavowel in the written description or prosecution history, Judge O'Malley disagreed with the majority and the district court to the extent they found the construction required "continuous microtexturing" over the entire skin layer.

Judges: O'Malley (concurring-in-part and dissenting-in-part), Plager (concurring),
Reyna (author)

[Appealed from D. Minn., Judge Frank]

This article previously appeared in Last Month at the Federal Circuit, September 2013

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