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Proving Prior Invention Does Not Require That the Prior Inventor Appreciated the Subject Matter Using the Same Words of the Claim

December 01, 2011

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Last Month at the Federal Circuit - January 2012

Judges: Rader, Dyk, Linn (author)

[Appealed from: E.D. Pa., Judge Yohn]

In Teva Pharmaceutical Industries Ltd. v. AstraZeneca Pharmaceuticals LP, No. 11-1091 (Fed. Cir. Dec. 1, 2011), the Federal Circuit affirmed the district court’s grant of SJ of invalidity of certain claims of Teva Pharmaceutical Industries Ltd.’s (“Teva”) U.S. Patent No. RE39,502 (“the ’502 patent”) based on AstraZeneca Pharmaceuticals LP’s (“AstraZeneca”) prior invention under 35 U.S.C. § 102(g)(2).

AstraZeneca manufactures and sells the drug CRESTOR®, which is a statin (rosuvastatin calcium) formulation for the treatment of dyslipidemia. Because statins are inherently unstable compounds, they must be manufactured in stabilized formulations. Therefore, AstraZeneca designed the CRESTOR® composition with the stabilizer tribasic calcium phosphate. CRESTOR® also contains crospovidone, which AstraZeneca included as a disintegrant.

Teva sued AstraZeneca for infringing several claims of the ’502 patent by manufacturing and selling CRESTOR®. The asserted claims are directed to statin formulations stabilized exclusively by an amido-group containing polymeric compound (“AGCP compound”) or by an amino-group containing polymeric compound. Teva asserted that it had conceived and reduced to practice its claimed invention by December 1, 1999.

It was uncontested that AstraZeneca intended to use tribasic calcium phosphate, which is not an AGCP compound, as the stabilizer in its formulation, and it did not appreciate, prior to December 1, 1999, the alleged stabilizing effect of crospovidone, an AGCP compound, in CRESTOR®. It was also undisputed that AstraZeneca manufactured multiple batches of rosuvastatin calcium with the same ingredients in substantially the same amounts as its CRESTOR® composition beginning in mid-1999 and publicly disclosed the ingredients and quantities for its rosuvastatin formulation.

Based on these facts, AstraZeneca moved for SJ of invalidity under 35 U.S.C. § 102(g)(2), alleging prior invention of the subject matter of Teva’s asserted claims. For the limited purpose of advancing its SJ motion, AstraZeneca conceded infringement of Teva’s claims. The district court granted AstraZeneca’s motion and held the asserted claims invalid in light of AstraZeneca’s prior invention. Teva appealed.

The Federal Circuit noted that it was undisputed for purposes of the appeal that the CRESTOR® composition fell within the scope of the asserted claims because AstraZeneca conceded infringement and Teva maintained its infringement allegation upon which the suit was based. It was also undisputed that AstraZeneca’s conception and reduction to practice of CRESTOR® occurred prior to Teva’s conception of the claimed subject matter, and that AstraZeneca did not appreciate the alleged stabilizing effect of crospovidone in its CRESTOR® composition. Therefore, the only question before the Court was whether, as a matter of law, AstraZeneca had to appreciate that crospovidone stabilized the drug in order to prove prior invention under § 102(g)(2).

The Federal Circuit rejected Teva’s argument that, to prove prior invention, AstraZeneca had to show that it appreciated that the amount of crospovidone in its earlier composition had a stabilizing effect. Relying on Dow Chemical Co. v. Astro-Valcour, Inc., 267 F.3d 1334 (Fed. Cir. 2001); Mycogen Plant Sciences v. Monsanto Co., 243 F.3d 1316 (Fed. Cir. 2001); and Invitrogen Corp. v. Clontech Laboratories, Inc., 429 F.3d 1052 (Fed. Cir. 2005), the Court stated that the party asserting prior invention must prove that it appreciated what it had made, but the prior inventor did not need to know everything about how or why its invention worked and did not need to “conceive of its invention using the same words as the patentee would later use to claim it.” Slip op. at 11. Thus, because AstraZeneca had conceded infringement (such that the amount of crospovidone fell within the claimed “stabilizing effective amount”), the Federal Circuit held that AstraZeneca only had to appreciate (1) that the composition it asserted as its prior invention was stable, and (2) what the components of the composition were. It did not need to appreciate which component was responsible for the stabilization. Because AstraZeneca had the requisite appreciation, the Court rejected Teva’s argument regarding crospovidone’s alleged stabilizing effect.

Second, the Federal Circuit dismissed Teva’s argument that the district court incorrectly applied the doctrine of inherent anticipation in the § 102(g)(2) context, because Teva’s infringement allegations and AstraZeneca’s limited concession of infringement removed any factual dispute about whether or not the prior art includes a certain claim limitation (expressly or inherently).

Finally, the Court rejected Teva’s argument that AstraZeneca suppressed or concealed its prior invention by not disclosing that crospovidone had a stabilizing effect because, as noted above, AstraZeneca did not need to appreciate this supposed property of crospovidone.

Accordingly, the Federal Circuit affirmed the district court’s grant of SJ under 35 U.S.C. § 102(g)(2) invalidating the asserted claims of the ’502 patent.

Summary authored by Daniel A. Lev, Ph.D., Esq.