CAFC Provides Further Guidance on Means-Plus-Function

Welker Bearing Co. v. PHD, Inc. 08-1169, December 15, 2008

Welker appealed the district court's summary judgment of noninfringement. As part of the appeal, Welker challenged the district court's interpretation of "mechanism for" as a means-plus-function term under §112 ¶ 6. Finding the word "mechanism" to be insignificantly different from "means", the CAFC found that

In this instance, the ’254 patent’s claim language does not include the word “means,” but instead the similar word “mechanism.” . . . This court noted that “[t]he generic terms ‘mechanism,’ ‘means,’ ‘element,’ and ‘device,’ typically do not connote sufficiently definite structure [to avoid means-plus function treatment] . . . The term ‘mechanism’ standing alone connotes no more structure than the term ‘means.’” . . . [t]he unadorned term “mechanism” is “simply a nonce word or a verbal construct that is not recognized as the name of structure and is simply a substitute for the term ‘means for.’”

With regards to infringement, defendant PHD argued that one of the accused products did not "infringe" because they were prototype units that were provided to 3rd parties, but never entered production, sold, or or otherwise used commercially. The CAFC agreed with PHD:

Mere possession of a product which becomes covered by a subsequently issued patent does not constitute an infringement of that patent until the product is used, sold, or offered for sale in the United States during the term of the patent . . . PHD did not have any burden to prove it retracted any putative offer for sale. Rather the burden remains with the patentee to prove infringement, not on the defendant to disprove it. In any event, this court observes that the district court properly concluded, “Defendant’s flat denial, backed by evidence, of any commercial activity after September 7, 2004 stands uncontradicted by anything in the record.” . . . For that reason, this court holds that the district court did not err in granting
summary judgment of noninfringement of the ’478 patent.

Also, with regard to the doctrine of equivalents and §112 ¶ 6, the CAFC clarified that

Structural equivalents and the doctrine of equivalents are “closely related.” . . . They are related in the sense that both § 112 ¶ 6 and the doctrine of equivalents apply “similar analyses of insubstantiality of the differences” between a disclosed structure and an accused infringing structure . . . However, an important difference between the two inquiries “involves the timing of the separate analyses for an ‘insubstantial change.’” . . . Namely, an equivalent structure under § 112 ¶ 6 “must have been available at the time of the issuance of the claim,” whereas the doctrine of equivalents can capture after-arising “technology developed after the issuance of the patent.”

AFFIRMED

Read/download the opinion here.