Appeals from the District Court of the United States for the Eastern District of Wisconsin.
Before ALSCHULER, EVANS, and FITZHENRY, Circuit Judges.
The defense to claim 4 of the Clutter patent is non-infringement. Claim 4 reads:
"In an excavating machine a pivoted boom, a scoop-carrying member pivotally connected therewith, a pulling member for elevating and lowering said boom, a pivotal means carried by the boom and connecting the pulling member therewith, and said scoopcarrying member, a scoop connected with the scoop-carrying member and projecting toward the boom, and a pulling member connected with said scoop."
Non-infringement is asserted on the ground that none of the alleged infringing machines has the element described in the italicized words of the above-quoted claim. In fact, it may be said that infringement turns on the use of the word "carried" as it appears in this element. In other words, it is clear that infringement is shown if the pivotal means therein referred to is "carried by the boom." On the other hand, infringement is avoided unless the court is justified in holding that appellants' machines have a "pivotal means carried by the boom" or its mechanical equivalent.
There can be no dispute as to the facts for none of appellants' machines has its pivotal means fixedly resting upon the boom.
In order to better understand the scope of the invention we quote from the specifications:
"This invention relates to excavating machines chiefly used for excavating cellars, trenches and in deepening and widening water courses, and has for its object to provide a simply constructed and operated mechanism for loading, elevating and emptying a scoop and which may be attached to any suitable machine available for the character of the work referred to.
"The invention consists mainly in the arrangement of the scoop, the scoop-carrying member, and boom for the two pulling members making it possible for the operator, to extend the scoop beyond the end of the boom, to raise and lower the boom or fill the scoop by manipulating the two pulling members."
Appellants reply upon the file wrapper to support their argument that the claim should be limited to the strict language which the inventor adopted when he described the said pivotal means in this combination claim. The file wrapper supports this argument. Upon the rejection of his application for a patent March 31, 1916, the inventor amended or rewrote his claims. The claim in suit thereupon made its first appearance. In presenting this claim (4) after the rejection of pending claims, the applicant wrote
"It will be pointed out that none of the references disclose a pivoted boom, a scoopcarrying member pivotally connected therewith, a pulling member for elevating and lowering the boom, a scoop carried by the scoopcarrying member and projecting towards the pulling member, and means carried by the boom for connecting the pulling member therewith and with said scoop-carrying member.
"Attention is directed to the last element.
"The applicant was the first in the art to mount a means upon the boom for connecting a pulling member therewith but also for connecting the pulling member with the scoop-carrying member."
In view of the language of claim 4 and the position of the inventor thus taken when he substituted this claim for rejected claims, we do not feel at liberty to ignore the words of limitation, "carried by the boom" when construing the language or determining the scope of this claim. The drawings confirm this conclusion.
As none of the infringing machines are so constructed (that is, none of them has a pivotal member carried on the boom), it is impossible to sustain the finding of infringement except upon a most liberal application of the doctrine of equivalents.
Appellee argues that the Northwest machines "operate like and realize all of the advantages of the Clutter patent' * * *. The only differences between these two machines and each of the other machines charged to infringe is in the mechanical details of the means * * *." It further says:
"Defendants undertake to escape from this situation by asking the Court to first read into the claim a particular kind of means for connecting the hoisting line to the ditcher stick and, second, after having done so, to deny the ...