Before Newman, Lourie, and Schall, Circuit Judges.
The opinion of the court was delivered by: Lourie, Circuit Judge.
Appealed from: United States District Court for the Northern District of West Virginia Judge W. Craig Broadwater
Pharmacia & Upjohn Company ("Upjohn") appeals from the decision of the United States District Court for the Northern District of West Virginia granting summary judgment to Mylan Pharmaceuticals, Inc. The court held that Mylan did not infringe the claims of Upjohn's U.S. Patent 4,916,163 under the doctrine of equivalents because of prosecution history estoppel, and alternatively, that Upjohn was collaterally estopped from asserting its infringement claim by a prior judgment of invalidity and unenforceability. See Pharmacia & Upjohn Co. v. Mylan Pharm., Inc., 5 F. Supp. 2d 399, 46 USPQ2d 1831 (N.D. W. Va. 1998). Because the district court did not err in its Conclusions, we affirm.
The patent at issue involves formulations of the anti-diabetic drug glyburide that contain two key components: micronized glyburide (finely divided glyburide) and lactose. Lactose exists in both hydrous (the monohydrate) and anhydrous forms and acts as an excipient, i.e., an inactive ingredient, in pharmaceutical compositions. Hydrous lactose is difficult to use in manufacturing micronized glyburide formulations because of poor compressibility and poor hopper flow. To avoid those problems, "spray-dried lactose" (a particular form of hydrous lactose) or anhydrous lactose may be utilized. Both spray-dried and anhydrous lactose are readily compressible and have considerably larger particle size than hydrous lactose, qualities which facilitate tablet manufacture.
The '163 patent is directed to micronized glyburide formulations containing spray-dried lactose as the principal excipient. Claim 1, the only independent claim, is written in the Jepson format and reads as follows:
"1. In an [sic] micronized anti-diabetic pharmaceutical composition as a unit dose, containing one or more pharmaceutically acceptable excipients, the improvement which comprises: spray-dried lactose as the preponderant excipient in said composition, being present therein at about not less that [sic] seventy percent (70%) by weight of the final composition." '163 patent, col. 4, ll. 17-24.
Claim 2 more particularly claims micronized glyburide of a specific surface area, see id. at ll. 25-27, while claims 3 and 4 more particularly claim combinations of excipients to be used with micronized glyburide, see id. at ll. 28-33.
Mylan, a generic drug manufacturer, devised several micronized glyburide compositions, all of which use anhydrous lactose as the principal excipient; they contain no spray-dried lactose. Mylan filed an Abbreviated New Drug Application ("ANDA") with the Food and Drug Administration seeking approval to sell 1.5 mg and 3.0 mg micronized glyburide tablets before the expiration of the '163 patent. Mylan filed a supplement to the ANDA seeking approval for a 6.0 mg tablet as well. Pursuant to 21 U.S.C. § 355(j)(2)(B)(ii), on August 30, 1996, Mylan sent Upjohn a "Notice of Paragraph IV Certification" notifying Upjohn of its submission of an ANDA for the 1.5 and 3.0 mg tablets and explaining why its tablets did not infringe the claims of the '163 patent. On December 31, 1996, Mylan sent Upjohn a similar notification letter regarding its supplemental ANDA for the 6.0 mg tablets.
Upjohn sued Mylan in the district court alleging that Mylan's filing of the ANDA with respect to the 1.5, 3.0, and 6.0 mg compositions constituted infringement of claims 1 through 4 of the '163 patent under 35 U.S.C. § 271(e)(2). Conceding a lack of literal infringement, Upjohn alleged that Mylan's micronized glyburide compositions infringe under the doctrine of equivalents because "anhydrous lactose" is the equivalent of "spray-dried lactose." Mylan moved for summary judgment, arguing that Mylan did not infringe because of prosecution history estoppel, and alternatively, that Upjohn was collaterally estopped by the judgment of invalidity and unenforceability in Upjohn Co. v. MOVA Pharmaceutical Corp., 48 USPQ2d 1357 (D.P.R. 1998).
As to infringement under the doctrine of equivalents, the district court observed that throughout the prosecution of the '163 patent, Upjohn emphasized the "criticality" of using spray-dried lactose as the principal excipient in its micronized glyburide formulations. See Mylan, 5 F. Supp. 2d at 403, 46 USPQ2d at 1835. The court indicated that Upjohn relied on the spray-dried lactose limitation to obtain issuance of the claims and argued to the Board of Patent Appeals and Interferences (the "Board") that if spray-dried lactose were not used, the advantages of the invention would not be realized. See id. The court reasoned that "[a] reasonable competitor could have concluded that Upjohn had relinquished any interpretation of its claim that would cover glyburide compositions containing nonspray-dried lactose instead of spray-dried lactose." Id. The court thus held that based on assertions made during prosecution of the application, Upjohn was barred from relying on the doctrine of equivalents by prosecution history estoppel. See id. at 404, 46 USPQ2d at 1835.
As an alternative basis for summary judgment, the district court held that Upjohn was collaterally estopped by the judgment of invalidity and unenforceability in MOVA under Blonder-Tongue Laboratories, Inc. v. University of Illinois Foundation, 402 U.S. 313, 169 USPQ 513 (1971). See Mylan, 5 F. Supp. 2d at 407, 46 USPQ2d at 1838; *fn1 see also MOVA, 48 USPQ2d at 1360-62 (denying Upjohn's motion for judgment as a matter of law (JMOL)/new trial and upholding, inter alia, the jury verdicts that 1) claims 1 and 3 of the '163 patent were invalid as obvious and 2) the patent was unenforceable due to inequitable conduct). Upjohn appealed both the prosecution history estoppel and collateral estoppel rulings to this court. We have jurisdiction pursuant to 28 U.S.C. § 1295(a)(1) (1994).