NOTE: This disposition is nonprecedential.

United States Court of Appeals 

for the Federal Circuit ______________________ 

ASTRAZENECA AB, AKTIEBOLAGET HASSLE,

ASTRAZENECA LP, KBI INC., AND KBI-E INC.,

Plaintiffs-Appellants,

v.

HANMI USA, INC., HANMI PHARMACEUTICAL 

CO., LTD., HANMI FINE CHEMICAL CO., LTD.,

AND HANMI HOLDINGS CO., LTD.,

Defendants-Appellees.

______________________ 

2013-1490

______________________ 

Appeal from the United States District Court for the 

District of New Jersey in No. 11-CV-0760, Judge Joel A. 

Pisano.

______________________ 

Decided: December 19, 2013

______________________ 

JAY I. ALEXANDER, Covington & Burling LLP, of 

Washington, DC, argued for plaintiffs-appellants. With 

him on the brief were EINAR STOLE and ERIC R.

SONNENSCHEIN. Of counsel on the brief were HENRY J.

RENK, BRUCE C. HAAS, and JOSHUA I. ROTHMAN, Fitzpatrick, Cella, Harper & Scinto, of New York, New York. 
2 ASTRAZENECA AB v. HANMI USA, INC. 

BLAIR M. JACOBS, McDermott Will & Emery, LLP, of 

Washington, DC, argued for defendants-appellees. With 

him on the brief were CHRISTOPHER G. PAULRAJ and 

PATRICK J. STAFFORD. Of counsel on the brief were MARK 

BOLAND, MICHAEL R. DZWONCZYK, and RENITA S.

RATHINAM, Sughrue Mion, PLLC, of Washington, DC. 

______________________ 

Before DYK, MOORE, and TARANTO, Circuit Judges. 

TARANTO, Circuit Judge. 

Plaintiffs AstraZeneca AB, Aktiebolaget Hassle, 

AstraZeneca LP, KBI Inc., and KBI-E Inc. (collectively, 

AstraZeneca) sued Defendants Hanmi USA, Inc., Hanmi 

Pharmaceutical Co., Ltd., Hanmi Fine Chemical Co., Ltd., 

and Hanmi Science Co., Ltd., formerly Hanmi Holdings 

Co., Ltd. (collectively, Hanmi). Invoking 35 U.S.C. 

§ 271(e)(2), AstraZeneca alleged that a drug Hanmi 

proposed to market falls within claims of U.S. Patent Nos. 

5,714,504 and 5,877,192. After the district court construed the claim terms “alkaline salt” in the ’504 patent 

and “pharmaceutically acceptable salt” in the ’192 patent, 

the parties consented to the entry of a final judgment of 

noninfringement based on the constructions. 

This appeal presents a single issue: whether the written description limits “alkaline salt” in the ’504 patent to 

certain specifically named salts. We hold that it does. 

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. 

BACKGROUND

Omeprazole is an “effective gastric acid secretion inhibitor[], and [is] useful as [an] antiulcer agent[].” ’504 

patent, col. 1, lines 22-23. Two distinct molecules have 

omeprazole’s molecular formula and sequence of bonded 
ASTRAZENECA AB v. HANMI USA, INC. 3

atoms. These “enantiomers” of omeprazole are mirrorimages, which cannot be superimposed on each other. A 

mixture of the enantiomers in equal amounts is a “racemate” of omeprazole (or “racemic” omeprazole). 

Creating a salt out of omeprazole can enhance stability during storage and transportation, a useful property in 

pharmaceutical compounds. See J.A. 5442 (describing the 

increased stability of certain salts of the racemate). Salts 

are chemical compounds composed of two oppositely 

charged ions: one positive (the cation) and the other 

negative (the anion). In an omeprazole salt, the omeprazole molecule is the anion. Several cations have proved 

suitable for omeprazole, including the metals from Groups 

IA and IIA of the Periodic Table. J.A. 5259. 

AstraZeneca discovered that certain salts of an 

omeprazole enantiomer, as opposed to the racemate, have

“improved pharmacokinetic and metabolic properties 

which will give an improved therapeutic profile such as a 

lower degree of interindividual variation.” ’504 patent, 

col. 1, lines 51-54. Its original application for the ’504 

patent, filed in 1995 as a continuation-in-part of a 1994 

application, described and claimed particular salts, defined by six identified cations: Na+, Mg2+, Li+, K+, Ca2+, or 

N+(R)4, where R is an alkyl with one to four carbons. Id. 

col. 1, line 1, to col. 6, line 35; J.A. 82-85. (The last formula denotes a class of ammonium cations, but for present 

purposes we may refer to it with the singular “cation”—

making six cations in all.) 

During prosecution, AstraZeneca conducted experiments that led it to conclude that one of the two enantiomers gave particularly good results. J.A. 312-25. The 

preferred enantiomer is known as “(-)-omeprazole” or “(S) 

omeprazole,” sometimes written as “esomeprazole.” In 

early 1997, in response to the Examiner’s rejection of 

original claims, AstraZeneca filed amended claims to 

focus on that enantiomer. J.A. 121, 296-309; see also ’192 
4 ASTRAZENECA AB v. HANMI USA, INC. 

patent, col. 2, lines 28-34 (continuation-in-part filed in 

April 1997, stating: “[O]ne of the enantiomers of omeprazole . . . is hereby claimed to be an improved alternative to 

omeprazole in the treatment of gastric acid related diseases resulting in higher dose efficiency and in less interindividual variation in plasma levels.”). The new claims, 

now at issue, are all limited to pharmaceutical compounds 

that contain certain esomeprazole salts as an active 

ingredient; but the independent claims no longer expressly refer to the originally identified six cations, instead

claiming an “alkaline salt” or “pharmaceutically acceptable salt.” See ’504 patent, col. 14, lines 5-49; ’192 patent, 

col. 7, line 17, to col. 8, line 54. 

AstraZeneca sells Nexium®, a product whose active 

ingredient is the magnesium (Mg2+) salt of esomeprazole, 

magnesium being one AstraZeneca’s original six cations. 

In December 2010, Hanmi filed an application with the 

Food and Drug Administration under 21 U.S.C. 

§ 355(b)(2) seeking approval to sell a product that contains the strontium (Sr2+) salt of esomeprazole, strontium 

not being one of AstraZeneca’s original six cations. The

application certified that the ’504 and ’192 patents are 

invalid or would not be infringed by Hanmi’s proposed 

product. 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). 

On December 12, 2012, the district court construed

the term “alkaline salt” in the ’504 patent and “pharmaceutically acceptable salt” in the ’192 patent. AstraZeneca 

argued that both terms have the same broad meaning: 

any “basic” salt of esomeprazole that is suitable for use in 

a pharmaceutical formulation. Hanmi argued that both 

terms are limited to the disclosed “Na+, Mg2+, Li+, K+, Ca2+

or N+(R)4 salts of the single enantiomers of omeprazole.” 

’504 patent, col. 2, lines 42-44. The district court agreed 

with Hanmi, concluding that the written description
ASTRAZENECA AB v. HANMI USA, INC. 5

defines the invention as limited to the disclosed salts. 

AstraZeneca AB v. Hanmi USA, Inc., No. 11-CV-0760, 

2012 WL 6203602, at *3-4 (D.N.J. Dec. 12, 2012). And

because the court held that the ’192 patent incorporates 

the ’504 patent’s disclosure, it construed “pharmaceutically acceptable salt” the same way. Id. at *6-7. 

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. Consent 

Order and Final Judgment, AstraZeneca AB v. Hanmi 

USA, Inc., No. 11-CV-0760, Dkt. No. 338 (D.N.J. June 3, 

2013). Hanmi stipulated that both patents are valid and 

enforceable. Id. AstraZeneca timely appealed, and we 

have jurisdiction under 28 U.S.C. § 1295(a)(1).

DISCUSSION

The only issue on appeal is the proper construction of 

the claim term “alkaline salt,” a question that we decide 

de novo. E.g., Cybor Corp. v. FAS Techs., Inc., 138 F.3d 

1448, 1454-56 (Fed. Cir. 1998). Because 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.1

Independent claim 1 of the ’504 patent claims 

[a] pharmaceutical formulation for oral administration comprising a pure solid state alkaline 

1 AstraZeneca agrees that the salt limitations in 

both patents should be construed the same way. Br. of 

Appellant at 8. Like the district court, therefore, we focus 

on the ’504 patent.

 
6 ASTRAZENECA AB v. HANMI USA, INC. 

salt of the (-)-enantiomer of [omeprazole] and a 

pharmaceutically acceptable carrier. 

Id., col. 14, lines 6-10; see also id., col. 14, lines 21-26 

(independent claim 6, a method of administering “a pure 

solid state alkaline salt of the (-)-enantiomer of [omeprazole]”); id., col. 14, lines 27-34 (independent claim 7). It is 

undisputed that the term “alkaline salt,” on its face and 

outside the context of the ’504 patent, would not be limited to the six cations named in the district court’s claim 

construction. But we agree with the district court that 

this is a patent in which the written description, by clear 

disclaimer, limits the claim scope to those cations.

The first sentence of the Detailed Description declares: 

The present invention refers to the new Na+, 

Mg2+, Li+, K+, Ca2+ or N+(R)4 salts of the single enantiomers of omeprazole, where R is an alkyl with 

1-4 carbon atoms, i.e. Na+, Mg2+, Li+, K+, Ca2+ or 

N+(R)4 salts of (+)-[omeprazole] and 

(-)-[omeprazole], where R is an alkyl with 1-4 carbon atoms. 

Id., col. 2, lines 42-49. That language clearly defines “the 

present invention” not as salts of omeprazole, or salts of 

single enantiomers of omeprazole, but as a particular set 

of “new” salts of enantiomers of omeprazole, limited to the 

six named cations. The Abstract, though not grammatically a sentence, confirms the limiting disclaimer by 

identifying what AstraZeneca said was “novel”: “The novel 

optically pure compounds Na+, Mg2+, Li+, K+, Ca2+ or 

N+(R)4 salts of (+)-[omeprazole] or (-)-[omeprazole], in 

particular sodium and magnesium salt form thereof . . .” 

Id., Abstract. 

Those statements clearly confine the invention to the 

six identified cations, disclaiming anything else. See, e.g., 

Verizon Servs. Corp. v. Vonage Holdings Corp., 503 F.3d 
ASTRAZENECA AB v. HANMI USA, INC. 7

1295, 1308 (Fed. Cir. 2007); Honeywell Int’l, Inc. v. ITT 

Indus., 452 F.3d 1312, 1318-19 (Fed. Cir. 2006); SciMed 

Life Sys., Inc. v. Advanced Cardiovascular Sys., Inc., 242 

F.3d 1337, 1340-45 (Fed. Cir. 2001). The very specificity 

and origin of the list of cations for salts confirm the plain 

meaning of the disclaimer language. AstraZeneca’s 

expert attested that a skilled artisan would presumptively 

understand that all of the metals of Periodic Table Groups 

IA and IIA, plus ammonium as an “honorary” member of 

those Groups for these purposes, would be suitable for 

forming a salt with the negatively charged enantiomer. 

J.A. 5354. AstraZeneca chose only certain members of 

that presumptively suitable class: the first five of the six 

cations are metals in Groups IA and IIA, and the sixth is 

ammonium. By 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 calcium in the Periodic Table. 

AstraZeneca advances three arguments for concluding 

otherwise. These arguments do not suffice to overcome 

the clear disclaimer language of the written description.

First, AstraZeneca asserts that one passage in the 

written description shows an intent to cover salts other 

than those of the listed six cations. The sentence AstraZeneca relies on reads: “Alkaline salts of the single enantiomers of the invention are, as mentioned above, beside 

the sodium salts . . . and the magnesium salts . . . , exemplified by their salts with Li+, K+, Ca2+ or N+(R)4, where R 

is an alkyl with 1-4 C-atoms.” ’504 patent, col. 5, lines 7-

11. AstraZeneca reads the “exemplified” language to 

mean that all six of the cations identified in column 2 are 

just examples of a broader group that is the invention.

But the sentence does not say that. The “exemplified” 

language applies directly to only four of the six cations 
8 ASTRAZENECA AB v. HANMI USA, INC. 

and is not preceded by the word “also” or any other language that might have more affirmatively suggested an 

intent to treat all six identified cations as merely exemplary. The context is also important: the sentence comes 

after two paragraphs describing the salts from Periodic 

Table Group IA (involving sodium) and the salts from 

Group IIA (involving magnesium) and says that it is just 

repeating information that was “mentioned above.” In 

context, we think that the AstraZeneca-highlighted 

sentence is best read as summarizing the two preceding 

paragraphs, neither of which suggests that the invention 

is a broader class of salts than the group identified in 

column 2. This sentence does not negate the clear disclaimer language quoted above.

AstraZeneca next turns to the prosecution history, but 

it too does not overcome the clear disclaimer language in 

the patent. When AstraZeneca filed the application that 

issued as the ’504 patent, the language of the claims 

aligned perfectly with the written description’s clear 

language 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. J.A. 82. After the Examiner rejected those claims for anticipation and obviousness, 

J.A. 117-18, AstraZeneca shifted the focus to unexpected 

benefits achieved by using the (-)-enantiomer rather than 

the (+)-enantiomer. Whereas the original claims and 

written description treated the two enantiomers with 

parity, AstraZeneca now distinguished the prior art by 

amending the claims to cover only esomeprazole, which it 

argued “unexpectedly exhibits a different and more advantageous pharmacokinetic profile than the racemic 

mixture or the (+)-enantiomer of omeprazole.” J.A. 300. 

To support that assertion, AstraZeneca submitted clinical 

studies that, it explained to the Examiner, “involved both 

the monovalent sodium salt and the divalent magnesium 

salt of the (-)-enantiomer of omeprazole, thus supporting 
ASTRAZENECA AB v. HANMI USA, INC. 9

the full scope of the genus of alkaline salts disclosed in the 

application and as claimed herein.” Id. (emphasis added). 

AstraZeneca relies on the italicized language to argue 

for a broadening that overcame the disclaimer in the 

patent itself. But we think that AstraZeneca is making 

more of this passage than the language supports. In the 

context of an amendment that otherwise narrowed the 

rejected claims, and a written description that so clearly 

limited the invention to the identified salts, the statement 

on which AstraZeneca relies is, at a minimum, not clear 

enough to overcome the limitation. 

Neither this statement nor anything else in the prosecution history states that there is a substantial expansion 

being undertaken. The prosecution history does not 

mention, or include data for, any salt beyond the salts 

identified in the written description. And contrary to 

AstraZeneca’s contention, the reference to “the full scope 

of the genus of alkaline salts . . . as claimed” does not 

establish a disclaimer-overriding expansion to a wide 

class of alkaline salts beyond the alkaline salts identified 

in column 2. For one thing, the term “genus” can refer 

simply to an enumerated collection, without an independently unifying characteristic of the collection’s members—as when “genus” is used for a Markush-type claim

that recites a group whose members may have nothing in 

common but their membership in the group. See, e.g., Eli 

Lilly & Co. v. Teva Parenteral Meds., Inc., 689 F.3d 1368, 

1373 (Fed. Cir. 2012) (“generic, Markush-style claims”); 

Merck & Co. v. Mylan Pharms., Inc., 190 F.3d 1335, 1340

(Fed. Cir. 1999) (“Markush genus”); Abbott Labs. v. Baxter

Pharm. Prods., Inc., 334 F.3d 1274, 1280 (Fed. Cir. 2003) 

(“‘A Markush group is a sort of homemade generic expression . . .’”). In any event, the full language at issue refers 

to the “genus of alkaline salts disclosed in the application 

and as claimed herein.” (Emphasis added.) That language is naturally understood to limit the genus being 

described to the particular salts “disclosed in the applica-
10 ASTRAZENECA AB v. HANMI USA, INC. 

tion,” i.e., those based on the six enumerated cations. It 

certainly is not clear in conveying a broader meaning.

Finally, AstraZeneca presses an argument based on

claim differentiation, noting that each independent claim 

reciting an “alkaline salt” has a dependent claim that 

differs only by the addition of “wherein the alkaline salt is 

a Na+, Mg2+, Li+, K+, Ca2+ or N+(R)4 salt.” See ’504 patent, 

col. 14, lines 14-15; id., col. 14, lines 48-49. But “the 

doctrine of claim differentiation does not . . . override 

clear statements of scope in the specification.” The Toro 

Co. v. White Consol. Indus., Inc., 199 F.3d 1295, 1302 

(Fed. Cir. 1999). Here, what otherwise might be an 

inference from differences in claim language cannot 

override the unmistakable limitation of “alkaline salt” set 

out in the written description. 

CONCLUSION

 The written description of the ’504 patent contains a 

clear disclaimer of claim scope, and no other aspect of the 

intrinsic record clearly points the other way. 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. 

AFFIRMED