Court Opinion

ID: 9446919
Source: CourtListenerOpinion
Date Created: 2023-08-03 22:21:16.079693+00
Date Added: 2024-06-11T17:30:49.670650
License: Public Domain

MAGRUDER, Circuit Judge
(Retired) (concurring).
Although I agree with the majority opinion that the plaintiff may be entitled to some range of equivalents on the Novak patent No. 2,525,310 owned by it, I cannot assign this as a reason for reversing the judgment below.
With regard to the water content of the web, the patent teaches a reduction to “about 4% to 8% by weight”; this marks out an area of some five percentage points, which in the context of the process involved is quite indefinite. It is therefore difficult for me to understand “about” as further expanding these nebulous limits of terminal water content. Rather, it more logically may be read as a flag signaling the description’s inherent vagueness. It may be that a content of 3.8% or 8.2% would constitute infringement, on the doctrine of equivalents, but the patent can certainly not claim much more than that.
The limitation as to the temperature to which the web is heated seems to be even clearer. The patent repeatedly says, “approximately 190° F., to 212° F.,” and once adds, in the general description of the invention: “It will, however, be understood that the temperature of the paper as it progresses over these drying drums is from normal room temperature to about 212° F., and the drying is terminated before the temperature of the paper can rise higher”. This language, specifying not one temperature but a range of 22 degrees, even more indefinite than the moisture description, does not claim a significant range of equivalents. Moreover, the upper boundary emphasized by the language I have italicized is meaningful as the boiling or evaporation point of water, which the plaintiff concedes is the moisture element the patent refers to. In other words, the patent teaches heating water content up to, but not over, the boiling point. A process involving a temperature of 220 to 235 degrees Fahrenheit is pretty clearly not covered by the patent.
In any event, the question of equivalents, that is, whether the doctrine was applicable to this patent, was never really before the district court for decision, because it accepted moisture content figures of one to two per cent water1 or 14 to 17 per cent total volatiles, and temperature readings of 220° F. to 235° F., as describing defendant’s process — those figures, if they must be accepted, would as a matter of law put the defendant’s process outside the range of any possible equivalents.
On the other hand, however, I agree with the majority that there is a substantial issue of fact as to the test implied by the moisture content limitations-of the patent, for the reasons whichi *844Judge Hartigan has well discussed. Also, I am not satisfied that there is no remaining issue of fact as to the maximum temperature of defendant’s web; temperature was not treated as an alternative ground by the district court, which based its decision almost exclusively on the moisture content. On these limited grounds, I concur in the result reached by the majority opinion.

. This lies within the prior claims of the Weber patent, No. 1,960,176.