Bowser, Inc. v. Filters, Inc.

• Decision Date: 20 May 1968
• Docket Number: No. 21466.,21466.
• Citation: 396 F.2d 296
• Parties: BOWSER, INC., an Indiana Corporation, Appellant, v. FILTERS, INC., a California Corporation, Engineered Fabrications, Inc., a California Corporation doing business under the style of Enfab, Inc., and Lucian W. Taylor, Appellees.
• Court: U.S. Court of Appeals — Ninth Circuit

396 F.2d 296 (1968)

BOWSER, INC., an Indiana Corporation, Appellant, v. FILTERS, INC., a California Corporation, Engineered Fabrications, Inc., a California Corporation doing business under the style of Enfab, Inc., and Lucian W. Taylor, Appellees.

No. 21466.

United States Court of Appeals Ninth Circuit.

May 20, 1968.

Clarence E. Threedy (argued), of Threedy & Threedy, Bernard Hoban, Chicago, Ill., Lawrence Livingston, of Livingston, Borregard & Grant, San Francisco, Cal., for appellant.

L. N. Duryea (argued), of Duryea, Carpenter & Barnes, Santa Ana, Cal., Harlow P. Rothert, of Cushing, Cullinan, Hancock & Rothert, San Francisco, Cal., Donald R. Fraser, of Wilson & Fraser, Toledo, Ohio, for appellees.

Before DUNIWAY and ELY, Circuit Judges, and THOMPSON, District Judge.

THOMPSON, District Judge:

Bowser, Inc., owner of the Marvel patent for a fiber glass filter used in separating water from aviation fuel, brought an action for infringement against Lucian W. Taylor, the inventor of a competing filter, Engineered Fabrications, Inc., doing business as Enfab, Inc., who, under Taylor's control, did research on the development of the competing product and Filters, Inc., who manufactured it. The trial court found that there was no infringement and that the Taylor filter did not come within the claims of the Marvel patent. The question raised by the appeal is whether or not there was sufficient evidence to support these findings. We affirm.

To determine whether or not the Taylor filter infringes the Marvel patent, it is standard procedure in patent cases to compare the specifications of the accused product with the language of the patent claim. "If the accused matter falls clearly within the claim, infringement is made out and that is the end of it." Graver Tank & Mfg. Co. v. Linde Air Products Co., 339 U.S. 605, 607, 70 S.Ct. 854, 855, 94 L.Ed. 1097. To protect patents against infringement by similar products which vary in some insubstantial way from the language of the claim, a doctrine of equivalents has been evolved The theory of the doctrine is that "if two devices do the same work in substantially the same way, and accomplish substantially the same result, they are the same, even though they differ in name, form, or shape." Machine Co. v. Murphy, 97 U.S. 120, 125, 24 L.Ed. 935. The normal application of the doctrine is to find infringement where there is an insubstantial departure from the claim in order to prevent the working of a fraud on a patent by a similar, albeit not identical, device.

An opposite application of the doctrine is made, however, in the reverse situation to find no infringement by a product falling within the language of the claim which functions differently. "Thus, where a device is so far changed in principle from a patented article that it performs the same or a similar function in a substantially different way, but nevertheless falls within the literal words of the claim, the doctrine of equivalents may be used to restrict the claim and defeat the patentee's action for infringement." Graver Tank & Mfg. Co. v. Linde Air Products Co. (1950), 339 U.S. 605, 609, 70 S.Ct. 854, 856, 94 L.Ed. 1097.

The complaint alleged infringement of claims four and five¹ of the Marvel patent by the Taylor filter. Both filters are hollow cylinders composed of fiber glass elements constituting a porous cartridge. The filters are used primarily to separate water and foreign substances from aviation fuel. The Marvel claim is for a filter composed of superimposed fiber glass elements which have been separately compressed to a pre-determined density, a binder which maintains a uniform density throughout the elements, and a porous container to hold the elements assembled within the cartridge. An illustration of the Marvel filter on the patent claim shows it to be composed of stacked fiber glass elements, and the first claim of the patent is for "a water separator cartridge comprising a porous stack of elements, said elements comprising a number of layers of bonded fiber glass material * * *."

The principal difference between the Taylor filter and the Marvel patent is that in the Taylor filter, fiber glass mats are wrapped around a core and are then cured by heating them sufficiently to cause resins in the glass to bind the mats into tubular form without need of a container.

The thrust of Appellant's argument is that in spite of evidence that the claim was originally intended to apply to a filter of stacked elements, the Taylor filter of wrapped elements nonetheless infringes because wrapped elements fall within the language "superimposed porous elements" of claims four and five of the Marvel patent. This type of semantic reasoning is the danger which the reverse application of the doctrine of equivalents is designed to prevent. Although a grammarian might concede that wrapped elements are superimposed, Appellees have proved that wrapped filter elements were an improvement over stacked elements because of different flow characteristics. It was shown that in a filter composed of stacked elements, the flow of liquid was parallel to the fibers and that, under pressure, the liquid might create channels between the fibers and flow unfiltered. The flow of liquid through a wrapped filter is perpendicular to the plane of the fibers and no channeling results. It is clear from the evidence that the Taylor filter had functional advantages over the Marvel filter and was not a subterfuge developed to work a fraud on Appellant's patent. Under the doctrine of equivalents, the Taylor filter cannot be said to infringe the Marvel patent because its dissimilar characteristics are functional and not insubstantial.

The trial court made specific findings of the differences between the Mervel patent and the Taylor filter.² These findings expressly remove the Taylor filter from the literal language of the Marvel patent. They are supported by sufficient and competent evidence in the record. The Supreme Court of the United States, in Graver Tank & Mfg. Co. v. Linde Air Products Co., 339 U.S. 605, at 609-610, 70 S.Ct. 854,...