Print PDF

Wanderer Monitoring System Not Infringed

March 12, 2001

Decision icon Decision

Last Month at the Federal Circuit - April 2001

Judges: Clevenger (author), Smith, and Bryson

In Senior Technologies, Inc. v. R.F. Technologies, Inc., No. 00-1089 (Fed. Cir. Mar. 12, 2001) (nonprecedential decision), the Federal Circuit affirmed a district court’s ruling of noninfringement against Senior Technologies, Inc. (“Senior Tech”) in favor of R.F. Technologies, Inc. (“RF Tech”) on U.S. Patent No. 4,682,155 (“the ‘155 patent”) and denied RF Tech’s cross appeal of the district court’s ruling on issues of claim indefiniteness, invalidity, inequitable conduct, and attorney fees.

The ‘155 patent is directed to a monitoring system for use in nursing homes, hospitals, and other care facilities. The system has a transmitter and sensing module that monitors patients that tend to wander away from the facility and sounds an alarm to warn the facility staff if a patient wanders too far off.

The Federal Circuit addressed Senior Tech’s argument that the district court should not have excluded a microprocessor from the accused product when comparing the accused product to a recited “receiving circuit” limitation recited in the claims. The specification defines a “receiving circuit” and its functionality to include accepting an input signal, processing the input signal in successive stages, and delivering the signal to an output stage, the Court observed. However, the district court’s comparison of the “receiving circuit” to the accused products included circuitry preceding the microprocessor itself.

The Federal Circuit also disagreed with Senior Tech’s argument that the “receiving circuit” need not lie in a single housing. Claim 1 recites a “means to enable the receiving circuit in the sensing module,” indicating that the receiving circuit must be within the sensing module. This interpretation is consistent with the text and figures within the ‘155 patent specification. Further, the prosecution history reveals that amendments to claim 1 were made such that the “receiving circuit” would be located “in the sensing module” for clarifying reasons.

Claim 6 recites “a housing and a receiving circuit therein.” In addition to the claim language, the specification confirms this interpretation with “a housing 174 in which the receiv[ing] circuit is located.” Moreover, the prosecution history reveals an amendment to claim 6 incorporating the ”housing” and “receiving circuit” (originally separate elements) into a single element. In light of this intrinsic evidence, the Federal Circuit concluded that the receiving circuit in claim 6 is also located within a housing.

Contrary to the district court’s comparison, the Federal Circuit found that one of the accused products (the CA9000 model) could arguably meet the single-housing requirement while the remaining accused products could not and did not literally meet the claim limitation. The Federal Circuit further precluded expansion of the claim scope under the DOE because amendments were made to both claims 1 and 6 to overcome rejections. For these reasons, the Federal Circuit affirmed noninfringement of claims 1 and 6 for all but the accused CA9000 model.

The Federal Circuit also concluded that the proper location of an “associated sensing means” as recited in claim 1 was within the same “housing” as the “receiving circuit.” The claim language defined the sensing module as “including a receiving circuit and associated sensing means.” The specification reinforced this interpretation. Under the doctrine of claim differentiation, the Federal Circuit held that the “associated sensing means” in claim 1 is distinct from the “elongated sensing member” in claim 4. The Federal Circuit affirmed the district court’s conclusion of noninfringement because the accused product’s antenna (corresponding to the associated sensing means) is not within the same housing for literal infringement. Further, the Court ruled that Senior Tech could not use the DOE to eviscerate the construed limitation.

The final claim construction issue related to the phrase “to enable the receiving circuit” in both claims 1 and 6. The district court had found this phrase to mean the same for both claims, but the Federal Circuit held that what is enabled in claim 1 is different than what is enabled in claim 6 by virtue of qualifying language in claim 1. The Federal Circuit resolved inconsistencies within the specification by interpreting claim 1 to require only partial enablement of the circuitry due to the surrounding qualifying claim language and claim 6 to require full enablement of the circuitry due to a lack of other qualifying claim language.

While the Federal Circuit found that the district court had erred in its interpretation of this phrase, it held the error to be harmless due to earlier conclusions of noninfringement for claim 1. For claim 6, the Federal Circuit found that the structure in the accused products corresponding to the “receiving circuit” does not have to be “enabled” to receive transmitted signals. Thus, the Federal Circuit also affirmed the district court’s conclusion of noninfringement of claims 1 and 6 by the accused CA9000 product.

On cross appeal, RF Tech challenged various district court conclusions. Addressing RF Tech’s arguments, the Federal Circuit held that the different requirements for “enabling” the “receiving circuit” resolved the apparent inconsistencies in the specification and RF Tech’s arguments on indefiniteness. Regarding invalidity under 35 U.S.C. § 102(b), the Federal Circuit affirmed that a news article that reported the success of a prototype system in a field test and the fact that early versions were installed in two nursing homes prior to the critical date without door switches failed to describe the invention with sufficient detail and failed to be a public-use event prior to the critical date, respectively. Additionally, the Federal Circuit affirmed that failure to cite the news article and the early prototype use failed to establish the threshold issue of intent to mislead the PTO. Finally, the Federal Circuit affirmed there was insufficient evidence to prove the case was an “exceptional case” by clear and convincing evidence.