Sufficient structure recited in claim limitation using “means” to prevent application of – 112 – 6January 30, 2008

In a decision yesterday, the Federal Circuit reversed a district court's claim construction and the associated summary judgment of noninfringement. The district court held the relevant claim term was a means-plus-function limitation, as it used the word "means," as well as because in an interview summary in the prosecution history, it appeared the USPTO interpreted the term as a means-plus-function clause. Based on this interpretation, the court granted summary judgment of noninfringement, as the accused device did not have the required function.

The Federal Circuit reversed, holding the limitation in question was not a means plus function limitation as it recited the "exact structure that performs the function[] in question without need to resort to other portions of the specification or extrinsic evidence for an adequate understanding of the structure." Further, the attorney's remarks when the amendment was made indicated that the structure set forth in the claim was intended to perform the function. As a result, the claim element was not properly considered a means-plus-function element. Under the revised claim construction, there were genuine issues of material fact regarding infringement, resulting in the reversal and remand.

More details of TriMed, Inc. v. Stryker Corp. after the jump.

TriMed filed suit against Stryker, asserting infringement of a patent directed towards an apparatus for setting bone fractures. The invention uses screws, pins, and a plate fitting across a bone fracture, as shown below:

In the above figure, "the pin holes are positioned over the fractured bone fragment and the screw holes are positioned over the stable bone fragment."The relevant limitation of claim 1, the only claim at issue, reads "said holes in said plate providing 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." Stryker asserted this limitation was a means-plus-function limitation, based on its use of the word "means," creating a presumption that it is a mean-plus-function limitation, as well as a statement in an interview summary in the prosecution history where the examiner stated:

Agreement was reached that the expression of [the configuration of the pin to be attached to the plate in a sliding manner that prevents compression across the fracture] in a means-plus-function format and better defining the holes of the plate would distinguish over the prior art of record.

Based on this construction, Stryker contended that the limitation at issue required that surgeons "perform the functions of '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'" and that because its accused devices by themselves did not perform the functions, its devices did not infringe claim 1. The district court adopted Stryker's proposed claim construction as well as its reasoning regarding infringement, and entered summary judgment of noninfringement against TriMed. TriMed appealed.On appeal, TriMed argued that the limitation at issue was not properly considered a means-plus-function limitation. Use of the word "means" creates a rebuttable presumption that the limitation is a means-plus-function limitation. However, "[i]f, in addition to the word 'means' and the functional language, the claim recites sufficient structure for performing the described functions in their entirety, the presumption of § 112 ¶ 6 is overcome—the limitation is not a means-plus-function limitation." This occurs "when the claim language specifies the exact structure that performs the functions in question without need to resort to other portions of the specification or extrinsic evidence for an adequate understanding of the structure." Examining the claim language in this case, Federal Circuit noted that while the claim used "means" and disclosed functions, it likewise clearly articulated the structure (the holes) for performing the claimed functions, stating that "[t]he claim language makes clear that the structure for performing these functions is the holes themselves." The Federal Circuit thus noted that "[s]ince the claim language clearly identifies the structure for performing the functions in claim 1, it was unnecessary and inappropriate for the court to employ § 112 ¶ 6 and to hold that there must be a structure in addition to the holes (such as a slot) for performing these functions." The Federal Circuit likewise rejected Stryker's assertion that the prosecution history supported the means-plus-function construction, noting that the attorney remarks filed in conjunction with the amendment adding the limitation indicated "that it intended for holes by themselves to constitute structure sufficient for allowing pins to slide axially through without compressing the fracture and stabilizing the pin from displacement across the plane of the plate." Based on its revised claim construction, the Federal Circuit held that Stryker "failed to demonstrate that there is no genuine issue of material fact that its accused devices do not infringe on the '893 patent," and accordingly reversed the grant of summary judgment of noninfringement.

To read the full decision in TriMed, Inc. v. Stryker Corp., click here.