Woodstream Corporation v. Herter's, Inc., 20410.

CourtUnited States Courts of Appeals. United States Court of Appeals (8th Circuit)
Citation446 F.2d 1143
Docket NumberNo. 20410.,20410.
PartiesWOODSTREAM CORPORATION, Appellant, v. HERTER'S, INC. and George L. Herter, Appellees.
Decision Date15 September 1971

Robert T. Edell, Minneapolis, Minn., Merchant & Gould, John D. Gould, Minneapolis, Minn., for plaintiff-appellant.

H. Dale Palmatier, Minneapolis, Minn., Williamson, Palmatier & Bains, Herman H. Bains, Minneapolis, Minn., for defendants-appellees.

Before GIBSON and BRIGHT, Circuit Judges, and McMANUS, Chief District Judge.

BRIGHT, Circuit Judge.

Plaintiff Woodstream Corporation, a Pennsylvania corporation and long-time manufacturer and seller of animal traps, brought an action against the defendants, Herter's, Inc., a Minnesota corporation, and its president, George L. Herter, for patent infringement and unfair competition. Plaintiff, formerly the Animal Trap Company of America, is the assignee of the patents allegedly infringed. Woodstream alleges that the defendants distribute and sell animal traps embodying the improvements protected by the plaintiff's patents. The district court denied Woodstream any relief. Woodstream Corporation v. Herter's, Inc., 312 F.Supp. 369 (D.Minn.1970). Woodstream prosecutes this timely appeal.

Plaintiff alleges the infringement of two patents, Conibear, 3,010,245, issued November 28, 1961, and Lehn, 2,947,104, issued August 2, 1960.1 The defendants denied infringement, asserting the invalidity of the plaintiff's patents. The central issue on this appeal concerns the obviousness of the plaintiff's traps since the defendants concede the utility and novelty of these devices.2 The district court held the patents invalid, concluding that

While the Conibear and Lehn patents here in issue may satisfy the requirements of novelty and utility, the nature of the subject matter sought to be patented was obvious to a person having ordinary skill in the art, and for that reason the patents are invalid. 312 F.Supp. at 371

Appellant urges a reversal of the district court's decision, contending that the court's conclusions lack any evidentiary support, or, alternatively, that the trial court applied an erroneous standard of invention in finding plaintiff's two patents invalid.

Plaintiff Woodstream's claim against the defendants for unfair competition rests upon allegations that the defendants' reproduction and cataloging of conventional leg-hold type traps were so similar to the plaintiff's products as to create confusion in the market-place between plaintiff's traps and those of the defendants. The district court treated this issue as purely a factual question, and found that there was no proof that the defendants were deceiving the public, attempting to do so, or palming off their traps for the plaintiff's traps. On this appeal, plaintiff-appellant contends that federal law required the defendants to advertise their traps as being of foreign manufacture, in this case Japanese, and, further, that the findings of fact made by the district court upon this issue are not supported by the evidence.

Having fully reviewed an extensive record on this appeal, we conclude that the district court erred in holding the Conibear patent invalid. In all other respects, we affirm the district court's decision.


We turn initially to the patent infringement claims. The structures involved in the instant case are animal traps intended for fur trapping, particularly muskrats, beaver, marten, and other fur-bearing animals. The Conibear structure is a killer type trap, a steel trap which kills the entrapped animals through suffocation or by breaking the animal's neck. The Lehn device presents a trap similar in operation and configuration, except for a modification of the trigger element. These traps, referred to as "swing frame" traps, reflect a structure consisting of a pair of substantially identical rectangular frames, with one of the frames being slightly smaller and capable of rotating within the other frame. The two rectangular frames are hinged together or pivoted at a midpoint at their ends, with the sides of the frames comprising the jaws of the traps. When hinged and placed in a vertical position, the top and bottom sides of the two rectangular frames may be placed in a position parallel with each other. The jaws of the traps are held against the tension of a coil spring or springs in an open or set position by a sliding latch mechanism made of interconnecting wires constituting the trigger of the traps.

The Conibear trap is released by a wire extending into the center of the trap which disengages the latch member from one of the rectangular frames when the trigger arm which is directly attached to the latch becomes actuated by an animal entering the trap. The latch mechanism contains a diamond shaped wire element which pivots in any direction upon movement transmitted to it by the trigger arm; this movement affords a positive and quick release of the trap. Upon release, the jaws swing rapidly in opposite directions in egg beater fashion under the influence of a powerful coil spring to catch the animal. The following photograph3 demonstrates the Conibear trap in a set position.

The Lehn patent, except for some minor modifications in the construction of the pivotal aspects of the frames, reflects an improvement over the Conibear patent, specifically in the trigger mechanism. In the Lehn trap, the latch consists of a key-like mechanism with a collar at one end and U-notches at the other end. The collar encircles the frame side or jaw of the trap; it freely slides and rotates thereon. The opposite end of the latch grasps the second jaw by one of the U-shaped notches fitting on a partially cut-down sleeve which also freely slides and rotates upon the second frame side or jaw. A trigger arm extends from this cut-down sleeve into the trap. Movement against the trigger arm rotates this sleeve, positively forcing the U-notched latch out of engagement with the second jaw. In this way, the mechanism affords instantaneous release action. The following photograph shows a Lehn trap as set.

The defendants' alleged infringing traps, known as the "Hudson Bay Killer Traps," are almost identical in appearance and construction to the Lehn traps, except for a modification of the trigger arm and sleeve attachment to the second frame side or jaw of the trap. Like Lehn, a U-notched latch is rotatable and slideable on the first jaw. This latch engages the second jaw not directly upon a sleeve which is attached to the second jaw, but indirectly through a hinged second sleeve connecting to the trigger arm. This second sleeve contains a cut-down opening similar to that on the Lehn trap; it permits the notched latch mechanism to hold the two jaws in a set position. Movement against the trigger arm causes rotation and lifting of the notched latch which, in turn, produce instantaneous release action as in the Lehn device. The following photograph illustrates the slight differences between the allegedly infringing trap and Lehn.

The evidence introduced by the plaintiff establishes that the Conibear and Lehn type of swing frame trap constituted a substantial improvement over the old leg-hold trap previously used by trappers. The leg-hold trap has been the mainstay of the fur-trapping industry since first introduced in England in the Seventeenth Century. The leg-hold trap came into its modern form with the invention of the steel trap in the Nineteenth Century. The leg-hold trap, as its name implies, utilizes spring-loaded steel jaws which clamp around the leg of the animal when the animal steps into or releases the trap. These traps are deficient in several respects. They cause considerable pain and suffering for the trapped animal since the traps fail to kill the animal. They often work inefficiently because many trapped animals are able to work loose and escape. Many animals, particularly muskrats, escape by breaking the leg and then chewing it off. The leg-hold trap poses substantial danger to the trapper and, in some instances, its use reduces the quality of the animal's fur. On the other hand, the swing frame killer trap may be set faster, easier, and safer. Moreover, animals may be removed from it more quickly than from the conventional trap. One of the most significant advantages of the swing frame trap is its humane nature since in most cases it immediately kills the animal.

Despite evidence of the substantial advantages of the swing frame traps over the conventional leg-hold traps, the district court held, as to the Conibear and Lehn patents, that

Notwithstanding the greater utility, humaneness and commercial success of the Conibear type trap, factors certainly entitled to consideration when determining patentability, it appears to the Court that the features which characterize the Conibear and Lehn traps over the prior art are such as would be obvious to a mechanic skilled in the trap field at the time of the patenting of the Conibear and Lehn traps. 312 F.Supp. at 371-372.

The statutory requirement of non-obviousness for patentability rests upon 35 U.S.C. § 103, enacted in 1952, which provides:

A patent may not be obtained though the invention is not identically disclosed or described as set forth in section 102 of this title, if the differences between the subject matter sought to be patented and the prior art are such that the subject matter as a whole would have been obvious at the time the invention was made to a person having ordinary skill in the art to which said subject matter pertains. Patentability shall not be negatived by the manner in which the invention was made.

In Graham v. John Deere Co., 383 U.S. 1, 86 S.Ct. 684, 15 L.Ed.2d 545 (1966), the Supreme Court enunciated the guidelines of inquiry into obviousness under § 103:

Under § 103, the scope and content of the prior art are to be determined; differences between the

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