claims 4 and 5 in independent form for approval. Application claims 4 and 5, unlike the rejected application claims 1 and 11, stated that a portion of the adult backrest or seat bottom was rotatable "so as to reveal [the] child's seat such that [the] child's seat may be placed . . . in a position for receiving and protecting the child." Defs.' Mem. at 8-9; Defs.' Facts PP 29-30.
In rejecting application claims 1 and 11, the patent examiner referenced the Audi and Rothe devices. Significantly, both the Audi and Rothe devices utilize the backrest portion of an adult seat to form the bottom portion of a child seat. Wyttenbach's patent counsel, Kesterson, stated that in order to comply with the patent officer's recommendation, he canceled claim 4 and added all of the limitations in application claim 4 to application claim 1. On January 3, 1985, Kesterson filed amended claim 1 to the PTO. Kesterson testified that he believed that all of the limitations of application claim 4 were added to application claim 1 in the January 3, 1985 amendment. Defs.' Facts P 34. Kesterson further testified that he never intended to make amended application claim 1 either broader or narrower in scope than application claim 4, and that any wording differences between the two are simply the result of his attempt to make application claim 1 "read like normal English." Id. Additionally, plaintiffs admit that application "claim 1 was amended to incorporate the limitations of [application] claim 4" and that claim 1 of the '176 patent is neither narrower nor broader in scope than application claim 4. Id. P 35; Pls.' Facts P 35.
Defendants argue that the patent examiner's reference to these prior patents demonstrates the primary and critical difference between application claim 4 and application claims 1 and 11 -- that application claim 4 clearly stated that a portion of the adult backrest rotates "so as to reveal [the] child's seat such that the child's seat may be placed in . . . position for receiving and protecting a child." Id. The phrase " may be placed in . . . position for receiving and protecting a child" compels the conclusion that it also may not, and that a separate step must be employed to place the child seat in position for receiving and protecting a child. If another step is require after rotating the adult backrest, it stands to reason that the adult backrest does not form the child seat bottom. Defendants state that this distinction ultimately represents what the Patent Examiner rejected and what the Patent Examiner allowed, and makes clear that the claimed child seat and adult seat must be separate and distinct components of the asserted claims. Id.
The Court finds that defendants' arguments are supported by the undisputed evidence. Wyttenbach's counsel admitted that claim 1 was amended to include all of the limitations of application claim 4, and application claim 4 clearly required the adult seat to be rotated before the child seat could be folded down and made available for receiving the child. In doing so, Wyttenbach limited the permissible interpretations of his claims. See Baxa Corp. v. McGaw, Inc., 981 F. Supp. 1348, 1355 (D. Colo. 1997) (while the plain language of the claim may have been susceptible to the broad interpretation advanced by plaintiffs, plaintiffs' abandonment of certain interpretations during the prosecution history necessarily limits the permissible interpretations of the claim.) Moreover, plaintiffs fail to explain how their invention would survive comparison with prior art if we were to read the '176 patent in the broad manner advanced by plaintiffs.
In addition to the prior art referenced by the patent officer, there were no fewer than three patents prior to the '176 patent that described built-in automotive child seats. The Bernier Patent (No. 3,094,354), the Looney Patent (No. 2,294,039), and the Strahler Patent (No. 2,966,201) all show a child seat bottom that is formed from an adult seat back rest.
The Federal Circuit's decision in Dolly, Inc. v. Spalding & Evenflo Co., Inc., further supports our conclusion. 16 F.3d 394 (Fed. Cir. 1994). The Dolly court was asked to interpret the following portable child's chair claim: "a stable rigid frame which is formed in part from said side panels, and which along with said seat panel and said back panel provides a body supporting feature." 16 F.3d at 396. The court concluded that the claim's recitation of a two elements (the frame and the panels) and a relationship between the two, required the frame to be formed independent of the seat and back panels. Id. at 397.
Accordingly, the accused device that formed the frame from the side and back panels lacked a necessary limitation-- the frame-- and therefore did not infringe. Id. Similarly, the '176 patent recites two distinct elements, the adult seat and the child seat, and describes a relationship between the two-- the child seat is concealed "between said front and rear section" of the adult seat backrest-- that precludes a finding that the child seat can be formed by the adult seat.
This Court is obligated to interpret the '176 patent in a manner upholding its validity, when fairly possible. Becton Dickinson & Co. v. C.R. Bard, Inc., 922 F.2d 792, 799 n.6 (Fed. Cir. 1990). Accordingly, we interpret the '176 patent to require a child seat that is separate from and independent of the adult seat. Our finding gives full effect to the language in the claims of the '176 patent, constitutes the only embodiment found in the specification and drawings, and represents a reasonable interpretation of the prosecution history. In comparing the '176 patent to the accused device, we find that defendants' device utilizes the backrest of the adult seat to form the bottom of the child seat. The seat is equipped with a five point safety belt harness, used for restraining and protecting the child. The backrest of the adult seat is rotated down to form the child seat-- no further step is required to access the child seat. An oversized cushion is "Velcroed" to the bottom of the child seat with Velcro, providing comfort while enabling the seat to be readily removed for cleaning. The friction between the adult seat and the child seat cushion keeps the child seat in a vertical position until ready for use by a child. The affidavit of engineer Jeffrey Lambert, inventor of the Atoma device, is consistent with this interpretation.
Having interpreted both plaintiffs' and defendants' devices, we cannot conclude that defendants' child seat literally infringes upon the '176 patent. It is clear that the '176 patent contains the limitation requiring the child seat to be separate from the adult seat. Similarly, it is obvious that accused seats lack this limitation. Because literal infringement requires every limitation set forth in the '176 patent to be found in the accused device exactly, the lack of a separate child seat in the accused device precludes literal infringement. This is not the end of our inquiry, however, as we must determine whether defendants' device infringes upon the '176 patent under the doctrine of equivalents.
B. DOCTRINE OF EQUIVALENTS14
The modem doctrine of equivalents was set forth by the Supreme Court in Graver Tank & Mfg. Co. v. Linde Air Products Co., 339 U.S. 605, 94 L. Ed. 1097, 70 S. Ct. 854 (1950), and further refined in Warner-Jenkinson Co., Inc. v. Hilton Davis Chemical Co., 520 U.S. 17, 117 S. Ct. 1040, 137 L. Ed. 2d 146 (1997). Under this doctrine, a product or process that does not literally infringe upon the express terms of a patent claim may nonetheless infringe if there is equivalence between the elements of the accused product or process and the claimed elements of the patented invention. Warner-Jenkinson Co., 117 S. Ct. at 1049. Thus, the doctrine tries to "[prevent] a copyist from evading patent claims with insubstantial changes." Valmont Indus., Inc. v. Reinke Mfg. Co., Inc., 983 F.2d 1039, 1043 (Fed. Cir. 1993).
A patentee may invoke the doctrine of equivalents if the accused devise "performs substantially the same function in substantially the same way to obtain the same result."
See Zenith Electronics Corp. v. Exzec Inc., 1998 U.S. Dist. LEXIS 215, *16-17 (N.D. Ill. Jan. 5, 1998) (quoting Graver Tank, 339 U.S. at 608). Determining whether the accused device violates this "triple identity" test requires an objective
inquiry into the individual elements of the claim, not to the invention as a whole. Warner-Jenkinson, 117 S. Ct. at 1049. Therefore, a showing of overall equivalency of the patented product to the accused product will not be sufficient to prove infringement. Bradshaw v. Igloo Products Corp., 1997 U.S. Dist. LEXIS 13258, *9 (N.D. Ill. Sep. 2, 1997). This element- by- element analysis is meant to prevent the enlargement of a patent beyond the scope of its claims as allowed by the Patent and Trademark Office. Warner-Jenkinson, 117 S. Ct. at 1049.
In analyzing the claims of a patent, a court may examine the context of the patent, the prior art, and the particular circumstances of the case. Graver Tank, 339 U.S. at 609. A skilled practitioner's knowledge of the interchangeability between the claimed and accused elements is also relevant to the extent it sheds light on the concept of "equivalence." Undersea Breathing Sys., Inc., v. Nitrox Technologies, Inc., 985 F. Supp. 752, 1997 U.S. Dist. LEXIS 19065, *47 (N.D. Ill. 1997). "The proper time for evaluating equivalency - and thus knowledge of interchangeability between elements - is at the time of infringement, not at the time the patent is issued."
Warner-Jenkinson, 117 S. Ct. at 1053.
The scope of equivalency may be limited by the doctrine of prosecution history estoppel. Prosecution history estoppel prevents the patentee from recapturing subject matter that was surrendered during the prosecution in order to promote allowance of the claims. Undersea Breathing, 985 F. Supp. 752, 1997 U.S. Dist. LEXIS 19065, at *46-47. For example, if a claim has been narrowed by an amendment to avoid prior art rejection, the patentee may not argue that the surrendered subject matter is within the range of equivalents. Id at *46. However, if the patent-holder demonstrates that an amendment required during prosecution had a purpose unrelated to patentability, a court must consider that purpose in order to decide whether an estoppel is precluded. Warner-Jenkinson, 117 S. Ct. at 1050-51.
We note that in Hassell v. Chrysler Corp., an Ohio district court had an opportunity to analyze the Atoma device. 982 F. Supp. 515 (S.D. Ohio 1997). In doing so the court noted that the plaintiff's device required an additional step in deploying the child seat. Conversely, the Atoma product achieved a one-step, pull-down deployment. The Court concluded that this distinction, along with others, precluded a finding of equivalency. Id.
We similarly find that the one-step deployment afforded by the Atoma device is not the equivalent of the two-step deployment required by the '176 patent, because such a finding would read an express limitation out of the '176 patent. In the instant case, the doctrine of prosecution history estoppel prevents plaintiffs from attempting to recapture defendants' embodiment of the built-in child seat. It is clear that the patent examiner required Wyttenbach to incorporate the limitations set forth in application claim 4 -- including the limitation that the child seat may be folded down after the adult seat is rotated away--in order to achieve patentability. Plaintiffs have failed to demonstrate that the patent officer's direction was unrelated to patentability. To the contrary, the patent officer explained that, as presented, application claim I infringed upon prior art. Accordingly, plaintiffs cannot now attempt to recover the broad interpretation offered in application claim 1 through the doctrine of equivalents. International Visual Corp. v. Crown Metal Manufacturing Co., 991 F.2d 768 (Fed. Cir. 1993); see also Dolly, Inc. v. Spalding & Evenflo Co., Inc., 16 F.3d 394, 398-99 (Fed. Cir. 1994) (rejecting plaintiff's claim that the defendants' device infringed its patented child seat, where the plaintiff's device required a separate frame and defendants' did not, because the frame requirement was an express limitation of the patent.)
We find that the accused device does not infringe the '176 patent either literally or under the doctrine of equivalents. Therefore, plaintiffs' motion for summary judgment is denied and defendants' motion for summary judgment is granted. Furthermore, our analysis also compels us to deny plaintiffs' motion pursuant to Fed. R. Civ. P. 56(f). We expressly note that our finding of non-infringement is based exclusively upon our interpretation of plaintiffs' claim. BaxaCorp. v. McGaw, Inc., 981 F. Supp. 1348 (D. Colo. 1997) (acknowledging that interpretation of the plaintiff's claim, a matter of law, is usually outcome determinative). Because we find that further discovery is not likely to raise a genuine issue of material fact that would affect the Court's judgment, extending discovery is inappropriate. Theotokatos v. Sara Lee Personal Products, 971 F. Supp. 332 (N.D. Ill. 1997).
While both parties have developed child safety seats to be used in automobiles, their devices differ to a sufficient degree so as to preclude any finding of infringement. Accordingly, the defendants' motion for summary judgment is granted. The plaintiffs' cross-motion for summary judgment and Rule 56(f) motion for additional discovery are denied. The Clerk of the Court is instructed to enter final judgment for defendants and against plaintiffs pursuant to Fed. R. Civ. P. 58.
ENTERED Judge Ruben Castillo
Northern District of Illinois
MARCH 11, 1998