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Structural Elements in a Claim Reciting Means-Plus-Function Language Overcame the Presumption of § 112, ¶ 6 Jeremy S. Forest

January 29, 2008

Decision icon Decision

Last Month at the Federal Circuit - February 2008

Judges: Linn, Dyk, Moore (author)

[Appealed from: C.D. Cal., Judge Real]

In TriMed, Inc. v. Stryker Corp., No. 07-1327 (Fed. Cir. Jan. 29, 2008), the Federal Circuit reversed the district court’s grant of SJ of noninfringement of U.S. Patent No. 5,931,839 (“the ’839 patent”) and remanded the case for further proceedings. TriMed, Inc. (“TriMed”) sued Stryker Corporation (“Stryker”) for infringement of the ’839 patent. The ’839 patent is drawn to an implantable device for fixing bone fractures using screws, pins, and a plate with holes on one end for receiving screws and on the opposite end for receiving pins. In a particular embodiment, the plate is fitted across a bone fracture such that the pin holes are positioned over the fractured bone fragment and the screw holes over the stable bone fragment. The screws affix the plate to the stable bone fragment. The pins fixate the fracture by passing through the pin holes of the plate, traversing the fracture such that the pins penetrate the fractured bone fragments and embed in the stable bone fragment.

Claim 1 of the ’839 patent requires, among other things, that the holes in the plate are structured in a manner that provides “means for allowing the pin to slide axially therein but preventing compression across the fracture, and stabilizing said near end of the pin against displacement in the plane of the plate.” Slip op. at 3. According to an examiner interview summary, this language was added during prosecution to better define the holes of the plate in an effort to distinguish over the prior art of record.

At the district court proceedings, Stryker argued that the claim language at issue required surgeons to perform the functions of allowing the pin to slide laterally therein but prevent compression across the fracture. Additionally, Stryker alleged that the specific actions of a surgeon were required to stabilize the near end of the pin to prevent against displacement in the plane of the plate. Because, Stryker contended, its accused devices do not by themselves perform the claimed functions and that it does not supply the surgeons who may use the devices to perform the claimed functions, it cannot be held liable for infringement. Stryker also argued that the corresponding structures disclosed in the specification of the ’839 patent for performing the claimed functions require holes and some additional structural component. The district court adopted Stryker’s proposed claim construction and granted SJ of noninfringement.

On appeal, the Federal Circuit reversed. The Court held that the district court erred in concluding that the language at issue in claim 1 was means-plusfunction language that invoked § 112, ¶ 6. According to the Court, “the presence of the word ‘means’ and the articulation of a function is not the end of the inquiry. Just as clearly, the claim articulates the structure for performing the claimed function—the holes.” Slip op. at 5. Thus, the Court reasoned that it was unnecessary and inappropriate for the district court to employ § 112, ¶ 6. The Court also noted that even if they were to construe the disputed language of claim 1 under § 112, ¶ 6, the specification still disclosed an embodiment that has precisely the same structure as found in the accused Stryker devices.

The Court was not persuaded by Stryker’s argument regarding TriMed’s amendment to claim 1 during the prosecution of the ’839 patent. According to Stryker, TriMed’s addition of the word “means” to claim 1
requires that the language be construed as a means-plus-function limitation. However, the Court pointed out that the attorney remarks accompanying TriMed’s amendment indicate that the holes themselves were sufficient to impart the structure necessary to allow the pins to slide axially through without compressing the fracture and stabilizing the pin. Nowhere, according to the Court, did TriMed suggest the importance of any structure in addition to the holes.

The Federal Circuit noted that Stryker’s motion for SJ was premised solely upon reading the claim language at issue as a means-plus-function limitation. Accordingly, the Court ruled Stryker had failed to demonstrate that there was no genuine issue of material fact that its accused devices did not infringe the ’839 patent. The Court was not persuaded by Stryker’s counterargument that it did not supply the surgeons who were purportedly required to perform the claimed functions of the ’839 patent. The Court found that no credible reading of the claim language requires human input to perform the functions of the pinholes in TriMed’s plate.