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Equivalence Remains a Question of Material Fact When Specific, Detailed Evidence by Dueling Expert Witnesses Is Submitted

March 27, 2001

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Last Month at the Federal Circuit - April 2001

Judges: Clevenger (author), Schall, and Dyk

In Medical Device Technologies, Inc. v. C.R. Bard, Inc., No. 00-1378 (Fed. Cir. Mar. 27, 2001) (nonprecedential decision), the Federal Circuit held that Medical Device Technologies, Inc. (“MDT”) had raised material issues of fact as to infringement, rendering inappropriate a SJ of noninfringement.

MDT sued C.R. Bard, Inc. (“Bard”) for patent infringement of U.S. Patent No. 5,092,870 (“the ‘870 patent”), which is directed to spacer clips designed to maintain the relative spacing between a biopsy needle’s inner and outer needles. A biopsy needle is a specialized apparatus with two basic parts: an inner needle that has a hollowed-out portion for holding a tissue sample, and a hollow outer needle that slides over the inner needle. The ‘870 patent discloses a main body to which two splines are joined by connecting “webs.” The splines are resistively flexible and have hook members (or handles) on each end. To operate the spacer clip, the user presses in on the middle of the flexible splines that causes the splines to bow outwards, moving the hook members outward and allowing them to be placed around, or removed from, the plungers of the inner and outer needles of the biopsy needle. When the hook members engage the plungers, the inner and outer needles are maintained at a uniform separation.

The only claim at issue in the case comprised three limitations: (1) support body means, (2) handle receipt means, and (3) handle disengagement means. The district court construed all three limitations as means-plus-function limitations pursuant to 35 U.S.C. § 112, ¶ 6, and granted SJ based upon a finding that the allegedly infringing device did not infringe the “handle disengagement means” limitation of the claim. The district court’s analysis focused on the requirement that the infringing device contain identical or equivalent structure to the handle-disengaging means structure of the ‘870 patent. According to the Federal Circuit, however, this analysis improperly focused on only one portion of the handle-disengaging means structure–the resistively flexible spline–whereas the district court had construed the handle-disengagement means as including both a spline and webs.

Following its precedent, the Federal Circuit reasoned that the individual components of an overall structure that corresponds to the claimed function are not claim limitations. Instead, the claim limitation is the overall structure corresponding to the claimed function, and further deconstruction or parsing is incorrect. Accordingly, the Court concluded, a proper analysis should compare the ‘870 patent’s disengaging means with the infringing device’s disengaging means, in order to determine if these two structures are identical or equivalent. A component-by-component analysis under § 112, ¶ 6, is not appropriate.

In addition, both parties presented expert declarations on the issue of infringement. The two expert declarations reached opposite conclusions as to whether the infringing device contains structure equivalent to the handle-disengagement means of the ‘870 patent. Because equivalence remains a question of material fact when specific, detailed evidence by dueling expert witnesses is submitted, the Federal Circuit held that SJ is inappropriate on this issue. For these reasons, the district court’s decision was vacated and remanded for further proceedings consistent with the Court’s opinion.