The opinion of the court was delivered by: D. BROOKS SMITH
Seeking injunctive relief and damages, Johnstown America Corporation ("Johnstown") has sued Trinity Industries, Inc. ("Trinity") for patent infringement. Johnstown claims that Trinity's Aluminator II railway car infringes one or more of the claims of Johnstown's United States Patent No. 4,361,097 (the "'097 patent"), either literally or under the doctrine of equivalents. By counterclaim, Trinity seeks a declaratory judgment that the Aluminator II does not infringe any claim of the '097 patent. Trinity has filed a motion for summary judgment, arguing that no literal infringement exists as a matter of law and that Johnstown's claim under the doctrine of equivalents is barred by prosecution history estoppel.
I will grant Trinity's motion in part, because I agree that the Aluminator II does not literally infringe the '097 patent. I conclude, however, that prosecution history estoppel does not apply in this case. Accordingly, Johnstown may pursue its infringement claim under the doctrine of equivalents.
Johnstown's '097 patent, obtained in 1982, describes a gondola-style, top-dumping railway car commonly used to transport bulk materials, such as coal and gravel.
U.S. Patent No. 4,361,097, Docket No. 43, Exh. A, col. 1, lines 5-7. Johnstown's invention improved upon previous railway cars, which were designed as rectangular boxes with either flat bottoms or depressed centers. Id., col. 1, lines 11-19. The '097 patent improved a car's carrying capacity and lowered its center of gravity by "eliminating the hopper chutes, door frames, etc., from a conventional high side hopper car and substituting therefor a pair of concave troughs between the center sill and sides of the car." Id., col. 1, lines 40-43. Claims 1 and 6 of the '097 patent require that the "longitudinal axis" of each trough be parallel to the "longitudinal axis" of the center sill. Id., col. 3, lines 5-7; id., col. 4, lines 8-9. Diagrams of the '097 patent are attached hereto as Exhibit A.
Trinity built the Aluminator II under a patent it obtained in 1993. U.S. Patent No. 5,178,084, Docket No. 43, Exh. D. Like the '097 patent, the Aluminator II is a gondola-style, top-dumping railway car with concave troughs on either side of the center sill. The troughs on the Aluminator II, however, are not parallel to the center sill. Instead, each trough slopes up from the ends of the car, where the trough is deeper, rising toward the middle, where it forms an angle of approximately 3degree. Beck affidavit, Docket No. 41, P 23. Diagrams of the Aluminator II are attached hereto as Exhibit B. Trinity's patent states that the sloping troughs are an improvement over the '097 patent:
U.S. Patent No. 5,178,074, Docket No. 43, Exh. D, col. 1, lines 28-40.
Johnstown's claim for literal infringement turns on whether the longitudinal axes of the "bent" troughs on the Aluminator II are parallel to the longitudinal axis of the car's center sill, as required by claims 1 and 6 of the 1097 patent. If the axes are not parallel, then Trinity has not literally infringed the '097 patent. While the parties seem to agree on the meaning of "longitudinal axis" of a center sill, they disagree over the meaning of "longitudinal axis" of a trough, as that term is found in the '097 patent. Further, the parties agree that the prosecution history of the '097 patent provides insight into the meaning of the disputed term; they disagree, however, on the nature of that insight.
Prosecution History of the '097 Patent
The '097 patent contains nine claims. In Johnstown's original application, claims 1 and 6 read as follows:
1. A railway car for carrying bulk material having a pair of side walls and a pair of end walls supported by spaced trucks, the improvement comprising a floor structure having
(a) a center sill extending longitudinally over said trucks,
6. A floor for a railway car comprising a center sill and a pair of concave floor panels secured to opposite sides of and extending parallel to said center sill.
Patent application dated June 17, 1977, Docket No. 43, Exh. B, at 7-8.
In a decision mailed April 21, 1978, the federal Patent and Trademark Office rejected all nine claims. Decision by Examiner Howard Beltran, Docket No. 43, Exh. B, at 1. Although the examiner did not state explicitly his reason for rejecting claims 1 and 6, he provided an explanatory citation to 35 U.S.C. § 102 and United States Patent No. 1,412,660, registered in 1922 by Arthur T. Kuehner (the "Kuehner patent"). Id. at 2. Trinity contends, and Johnstown does not disagree, that a patent examiner must reject an application under 35 U.S.C. § 102 when he or she determines that the claimed invention is "anticipated by a single piece of prior art" -- i.e., when the prior art contains every element of the claimed invention. Beck affidavit, Docket No. 41, at P 12. Thus, we know that the examiner rejected the ...