Issue 149 | January 12, 2004
§112 ¶6 Equivalency Need Not
Focus on Physical Construction?
 In what appears to be dictum in Utah Medical Products v. Graphic Controls Corp. (Fed. Cir., No. 03-1081, 12/4/03 at http://www.fedcir.gov/opinions/03-1081.doc), Judge Rader quoted IMS Tech. v. Haas Automation, 206 F.3d 1422, 1430 (Fed. Cir. 2000) for the proposition that "Section 112, paragraph 6, requires two structures to be equivalent, but it does not require them to be ‘structurally equivalent,’ i.e., it does not mandate an equivalency comparison that necessarily focuses heavily or exclusively on physical construction. Rather the equivalents analysis under section 112, paragraph 6, proceeds with reference to the context of the invention and the relevant field of art."

The case involved a jury finding that the hard plastic, dual-lumen structure of a cable casing for an intrauterine pressure catheter was equivalent to the claimed "stiffening means permanently encased in an electrical cable means" for an intracompartmental pressure transducer. For performing the stiffening function, the patent disclosed only a steel stylet, a common medical device that is typically run through a catheter, cannula, or hollow needle to keep it stiff or clear of debris.

Although the patentee unsuccessfully attempted to use plastic to perform the stiffening function for its cable, the opinion dismissed that failure as being due to "cost constraints, not an inability to effectively use plastic." The opinion went on to cite expert testimony that the hard plastic cable was interchangeable as a stiffening member with a steel stylet. "Indeed," wrote Judge Rader, "the record illustrates the evolution of the stiffener means from a steel stylet to a hardened plastic in dual-lumen geometry" so that a reasonable jury could find those evolutionary differences to be insubstantial.

Are you also struggling with means-plus-function claim language interpretation? Send your thoughts to the author of this issue of "APLF Patent Law Updates," Bill Heinze (bill.heinze@tkhr.com), at Thomas, Kayden, Horstemeyer & Risley LLP in Atlanta, Georgia USA.

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