Astrazeneca AB v. Hanmi USA, Inc.: Construing “Alkaline Salts”

Category: Claim Construction  
By: Christian Hannon, Contributor 
TitleAstrazeneca AB v. Hanmi USA, Inc., No. 2013-1490 (Fed. Cir. Dec. 19, 2013) (non-precedential).
IssueThis appeal presents a single issue: whether the written description limits "alkaline salt" in [ AstraZeneca AB's U.S. Patent No. 5,714,504] to certain specifically named salts [found in the disclosures of AstraZeneca's patents]. Astrazeneca AB at *2 (text added).
HoldingWe hold that [the written description limits "alkaline salt" in the '504 patent to certain specifically named salts].The written description describes the invention clearly and narrowly as including only those salts and AstraZeneca points to nothing in the intrinsic record that is sufficient to overcome that disclaimer. Id. at *2 (text added).

Procedural HistoryThe district court [...] conclud[ed] that the written description defines the invention as limited to the disclosed salts. And because the court held that [AstraZeneca AB's U.S. Patent No. 5,877,192] incorporates the '504 patent's disclosure, it construed "pharmaceutically aceptable salt" [from the '192 patent] the same way. After the district court denied AstraZeneca's motion for reconsideration, the parties consented to the entry of a final judgment that the Hanmi product does not infringe under the district court's claim construction. Hanmi stipulated that both patents are valid and enforceable. AstraZeneca timely appealed. Astrazeneca AB at *4-5 (internal citations omitted, text added).
Legal Reasoning (Dyk, Moore, Taranto)
Asserted Patent Subject MatterAstraZeneca sells Nexium (R), a product whose active ingredient is the magnesium (MG2+) salt of esomeprazole, magnesium being one [of] AstraZeneca's origina[ly] [disclosed] six cations [that were disclosed by AstraZeneca to make the claimed esomeprazole]. In December 2010, Hanmi filed an application with the Food and Drug Administration [...] seeking approval to sell a product that contains the strontium (SR2+) salt of esomeprazole, strontium not being one of AstraZeneca's original six cations. On February 9, 2011, AstraZeneca filed suit, alleging that Hanmi's proposed product infringed the claims of the '504 and '192 patents under 35 U.S.C. § 271(e)(2)(A). Astrazeneca AB at *4 (text added, text deleted).
Construing "Alkaline Salts"
Clear disclaimer in written description limits claim scopeBecause the written description of the '504 patent contains a clear disclaimer of any salt except those using six enumerated cations, we agree with the district court that "alkaline salt" is limited to the Na+, MG2+, Li+, K+, Ca2+, and N+(R)4 salts of the now-claimed enantiomer of omeprazole. Astrazeneca AB at *5.
Clear disclaimer in written description limits claim scopeBy conspicuously choosing only certain members of the class, and using the language it did, AstraZeneca conveyed a clear and definitive meaning that it was disclaiming other members of the class--like Hanmi's chosen strontium, another metal from Group IIA, immediately below calcuim in the Periodic Table. Id. at *7.
Claims must be read in view of the specificationWhen AstraZeneca filed the application that issued as the '504 patent, the language of the claims aligned perfectly with the written description's clear langauge about the scope of the "present invention": the broadest of the claims were limited in terms to salts using the six identified cations, combined with either one of the two omeprazole enantiomers. Id. at *8.
We therefore conclude that the district court's construction of "alkaline salt" was correct, and we affirm the judgment of noninfringement based on that construction." Astrazeneca AB at *5.
Image Attribution Statement: U.S. Pat. 5,714,504. 
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