Cipla Ltd. v. Sunovion Pharmaceuticals Inc.

Filing 264

MEMORANDUM OPINION re claim construction. Signed by Judge Leonard P. Stark on 6/27/17. (ntl)

IN THE UNITED STATES DISTRICT COURT
FOR THE DISTRICT OF DELAWARE
CIPLA LTD.,
Plaintiff,
C.A. No. 15-424-LPS

v.
SUNOVION PHARMACEUTICALS INC.,
Defendant.

Mary B. Matterer and Richard K. Herrmann, MORRIS JAMES LLP, Wilmington, DE
Mitchell G. Stockwell, Anil H. Patel, and Joshua H. Lee, KILPATRICK TOWNSEND &
STOCKTON LLP, Atlanta, GA
Taylor H. Ludlam, KILPATRICK TOWNSEND & STOCKTON LLP, Raleigh, NC
Attorneys for Plaintiff.

Jack B. Blumenfeld, Karen Jacobs, Jennifer Ying, and Stephen J. Kraftschik, MORRIS,
NICHOLS, ARSHT & TUNNELL LLP, Wilmington, DE
David E. De Lorenzi, George Gould, Estelle Tsevdos, Wendy R. Stein, and Ankit D. Patel,
GIBBONS P.C., Newark, NJ
Attorneys for Defendant.

MEMORANDUM OPINION

June 27, 2017
Wilmington, Delaware

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S~ U.S. District Judg .
Plaintiff Cipla Ltd. ("Cipla") brought this patent infringement suit against Defendant
Sunovion Pharmaceuticals, Inc. ("Sunovion"), alleging that Sunovion' s Xopenex HFA® aerosol
inhaler infringes Cipla's U.S. Reissued Patent No. RE43,984 (the '"984 Reissue"). The asserted
patent describes and claims optically pure salbutamol salts of tartaric acid obtained by resolving a
racemic or otherwise optically impure mixture of salbutamol enantiomers with tartaric acid.
Presently before the Court is the issue of claim construction. The parties submitted technology
tutorials (see D.I. 89, 93), claim construction briefs (see D.I. 90, 94, 119, 146, 149), and expert
declarations (see D.I. 92, 96, 135-137). The Court held a claim construction hearing on May 1,
2017, at which both sides presented oral argument and expert testimony. (See D.I. 233 ("Tr."))

I.

LEGAL STANDARDS
The ultimate question of the proper construction of a patent is a question of law. See Teva

Pharm. USA, Inc. v. Sandoz, Inc., 135 S. Ct. 831, 837 (2015) (citing Markman v. Westview
Instruments, Inc., 517 U.S. 370, 388-91 (1996)). "It is a bedrock principle of patent law that the

claims of a patent define the invention to which the patentee is entitled the right to exclude."
Phillips v. AWH Corp., 415 F.3d 1303, 1312 (Fed. Cir. 2005) (internal quotation marks omitted).

"[T]here is no magic formula or catechism for conducting claim construction." Id. at 1324.
Instead, the court is free to attach the appropriate weight to appropriate sources "in light of the
statutes and policies that inform patent law." Id.
"[T]he words of a claim are generally given their ordinary and customary meaning ...
[which is] the meaning that the term would have to a person of ordinary skill in the art in
question at the time of the invention, i.e., as of the effective filing date of the patent application."
1

Id. at 1312-13 (internal citations and quotation marks omitted). "[T]he ordinary meaning of a
claim term is· its meaning to the ordinary artisan after reading the entire patent." Id. at 13 21
(internal quotation marks omitted). The patent specification "is always highly relevant to the
claim construction analysis.

Usua~ly,

it is dispositive; it is the single best guide to the meaning of

a disputed term." Vitronics Corp. v. Conceptronic, Inc., 90 F.3d 1576, 1582 (Fed. Cir. 1996).
While "the claims themselves provide substantial guidance as to the meaning of particular
claim terms," the context of the surrounding words of the claim also must be considered.
Phillips, 415 F.3d at 1314. Furthermore, "[o]ther claims of the patent in question, both asserted
and unasserted, can also be valuable sources of enlightenment ... [b]ecause claim terms are
normally used consistently throughout the patent .... " Id. (internal citation omitted).
It is likewise true that"[ d]ifferences among claims can also be a useful guide .... For

example, the presence of a dependent claim that adds a particular limitation gives rise to a
presumption that the limitation in question is not present in the independent claim." Id. at 131415 (internal citation omitted). This "presumption is especially strong when the limitation in
dispute is the only meaningful difference between an independent and dependent claim, and one
party is urging that the limitation in the dependent claim should be read into the independent
claim." SunRace Roots Enter. Co., Ltd. v. SRAM Corp., 336 F.3d 1298, 1303 (Fed. Cir. 2003).
It is also possible that "the specification may reveal a special definition given to a claim

term by the patentee that differs from the meaning it would otherwise possess. In such cases, the
inventor's lexicography governs." Phillips, 415 F.3d at 1316. It bears emphasis that "[e]ven
when the specification describes only a single embodiment, the claims of the patent will not be
read restrictively unless the patentee has demonstrated a clear intention to limit the claim scope
2

using words or expressions of manifest exclusion or restriction." Hill-Rom Servs., Inc. v. Stryker

Corp., 755 F.3d 1367, 1372 (Fed. Cir. 2014) (quoting Liebel-Flarsheim Co. v. Medrad, Inc., 358
F.3d 898, 906 (Fed. Cir. 2004)) (internal quotation marks omitted).
In addition to the specification, a court "should also consider the patent's prosecution
history, if it is in evidence." Markman v. Westview Instruments, Inc., 52 F.3d 967, 980 (Fed. Cir.
1995), aff'd, 517 U.S. 370 (1996). The prosecution history, which is "intrinsic evidence,".
"consists of the complete record of the proceedings before the PTO [Patent and Trademark'
Office] and includes the prior art cited during the examination of the patent." Phillips, 415 F.3d
at 131 7. "[T]he prosecution history can often inform the meaning of the claim language by
demonstrating how the inventor understood the invention and whether the inventor limited the
invention in the course of prosecution, making the claim scope narrower than it would otherwise
be." Id.
In some cases, "the district court will need to look beyond the patent's intrinsic evidence
and to consult extrinsic evidence in order to understand, for example, the background science or
the meaning of a term in the relevant art during the relevant time period." Teva, 135 S. Ct. at
841. Extrinsic evidence "consists of all evidence external to the patent and prosecution history,
including expert and inventor testimony, dictionaries, and learned treatises." Markman, 52 F.3d
at 980. For instance, technical dictionaries can assist the court in determining the meaning of a
term to those of skill in the relevant art because such dictionaries "endeavor to collect the
accepted meanings of terms used in various fields of science and technology." Phillips, 415 F.3d
at 1318. In addition, expert testimony can be useful "to ensure that the court's understanding of
the technical aspects of the patent is consistent with that of a person of skill in the art, or to
3

establish that a particular term in the patent or the prior art has a particular meaning in the
pertinent field." Id. Nonetheless, courts must not lose sight of the fact that "expert reports and
testimony [are] generated at the time of and for the purpose of litigation and thus can suffer from
bias that is not present in intrinsic evidence." Id. Overall, while extrinsic evidence "may be
useful" to the court, it is "less reliable" than intrinsic evidence, and its consideration "is unlikely
to result in a reliable interpretation of patent claim scope unless considered in the context of the
intrinsic evidence." Id. at 1318-19. Where the intrinsic record unambiguously describes the
scope of the patented invention, reliance on any extrinsic evidence is improper. See Pitney
Bowes, Inc. v. Hewlett-Packard Co., 182 F.3d 1298, 1308 (Fed. Cir. 1999) (citing Vitronics, 90
F.3d at 1583).
Finally, "[t]he construction that stays true to the claim language and most naturally aligns
with the patent's description of the invention will be, in the end, the correct construction."
Renishaw PLC v. Marposs Societa 'per Azioni, 158 F.3d 1243, 1250 (Fed. Cir. 1998). It follows
that "a claim interpretation that would exclude the inventor's device is rarely the correct
interpretation." Osram GmbH v. Int'! Trade Comm 'n, 505 F.3d 1351, 1358 (Fed. Cir. 2007)
(quoting Modine Mfg. Co. v. US. Int'! Trade Comm 'n, 75 F.3d 1545, 1550 (Fed. Cir. 1996)).

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II.

CONSTRUCTION OF DISPUTED TERMS
A.

"Levalbuterol L-tartrate" 1
"(R)-salbutamol-(L)-tartrate salt" 2

Cipla
"R-salbutamol salt of L-tartaric acid"
Sunovion
"A 1: 1 ratio of (R)-salbutamol cation and L-bitartrate monoanion" 3
Court
"R-salbutamol salt of L-tartaric acid"
The parties dispute whether the prosecution histories of the '984 Reissue and related
Cipla patents, which Sunovion characterizes as containing -a "long line of disclaimers" (D .I. 149
at 13), limit the scope of these terms to levalbuterol L-Bitartrate, the salt with a 1: 1 ratio of
levalbuterol cation and L-bitartrate monoanion. In Sunovion's view, "Cipla surrendered any
patent coverage to a tartrate salt made by using less than 1.0 mole equivalent of tartaric acid,"
and thereby surrendered any coverage over the 2: 1 variant of the compound, levalbuterol
hemitartrate. (Id.)
The Court finds that there is no "unambiguous disavowal that clearly and unmistakably
disclaims the plain meaning" of these claim terms. Biogen Idec, Inc. v. GlaxoSmithKline LLC,

This terin appears in claims 9 and 10 of the '984 ~eissue.

1

2

This term appears in claims 17 and 18 of the '984 Reissue. The parties agree that
Levalbuterol is another name for R-(-)-salbutamol, the compound's levorotatory enantiomer.
(See, e.g., D.I. 84-1 at 1 ("Levalbuterol L-tartrate ... is also known as R-salbutamol L-tartrate"))
3

Sunovion asks the Court to construe these same terms as-they appear in Sunovion's U.S.
Patent No. 7,256,310 (the "'3W patent")-which is not asserted i_n this case-as "[a] 2:1 ratio of
(R)-salbutamol cation and L-tartrate dianion." (D.I. 110-1 at 2 of 80 (emphasis added)) The ·
Court is not persuaded it is necessary or appropriate to do so.
5

713 F.3d 1090, 1098 (Fed. Cir. 2013) (internal quotation marks omitted).
Cipla, pointing to product labels and expert testimony, argues that "skilled artisans use the
term 'tartrate' to refer to both the 2:1 salt and the 1:1 salt." (D.I. 146 at 2 (citing D.I. 136 ~~ 1625)) The Court agrees that the "ordinary and customary" meaning of "Levalbuterol L-tartrate"
includes both the 2:1and1:1 forms. (See generally D.I. 147 Ex. A at 58-60 (Sunovion expert
testifying "there has been enormous sloppiness in the way in which the term 'tartrate' is used"))
Sunovion's principal contention is that Cipla made "repeated, clear, and unmistakable"
disclaimers in the prosecution histories by emphasizing use of a molar excess of tartaric acid to
salbutamol. (D.I. 149 at 16; see generally id. at 11-13, Table 1) To Sunovion, then, Cipla
"emphasized molar excess so many times and specifically disparaged the use of a molar
deficiency" that these claim terms "cannot be construed to ... include salts made by both a molar
excess and a molar deficiency," and therefore cannot cover both the 2: 1 and 1: 1 salts. (Id. at 15)4

4

The great majority of Sunovion's references to the intrinsic record refer not to the '984
Reissue's prosecution history, but instead to the prosecution history of its parent patent, U.S.
Patent No. 6,995,286 (the '"286 patent"), and of other related patents. (See, e.g., D.I. 149 at 1113, Table 1; D .I. 110-1 at 2-3) The '9 84 Reissue claims do not use the same claim terms as the
claims of the '286 patent. Hence, Cipla directs the Court to cases holding that "although a parent
patent's prosecution history may inform the claim construction of its descendant," the doctrine of
prosecution history disclaimer "generally does not apply when the claim term in the descendant
patent uses different language." Ventana Med. Sys., Inc. v. Biogenex Labs., Inc., 473 F.3d 1173,
1182 (Fed. Cir. 2006) (internal quotation marks omitted); see also Invitrogen Corp. v. Clontech
Labs., Inc., 429 F.3d 1052, 1078 (Fed. Cir. 2005) ("[T]he prosecution of one claim term in a
parent application will generally not limit different claim language in a continuation
application."); see also Regents of Univ. of Minnesota v. AGA Med. Corp., 717 F.3d 929, 943 n.8
(Fed. Cir. 2013) ("The sole exception is when the disclaimer is directed to the scope of the
invention as a whole, not a particular claim."). In response, Sunovion relies on Profoot, Inc. v.
Merck & Co., 663 F. App'x 928, 933 (Fed. Cir. 2016) (see Tr. at 89-91, 135-37; D.I. 216), where
the Federal Circuit observed that a parent patent's prosecution history "support[ed] the district
court's construction" of a claim term in a descendant patent. But Profoot stated that it was not
carrying forward any disclaimer that might appear in the parent's prosecution history, given the
differing claim language. Id. at 933 n.2.
6

But the doctrine of prosecution history disclaimer does not permit the Court to narrow the
ordinary meaning of a disputed claim term absent an "unambiguous disavowal[]," Grober v.

Mako Prods., Inc., 686 F.3d 1335, 1341 (Fed. Cir. 2012), and here Sunovion has identified no
such unambiguous disavowal.
Sunovion' s argument for finding a clear and unambiguous disclaimer essentially rests on
it proving that, at the pertinent time, a person of ordinary skill in the art ("POSA") would have

"expect[ed] a 1: 1 bitartrate salt to form from a resolution performed using a molar excess of
tartaric acid to resolution substrate." (D.I. 149 at 2 (citing, e.g., D.I. 96 ~~ 70-73; D.I. 137
~~

11-14; D.I. 150-1, Exs. A, B) (emphasis added)) But a general expectation is not enough.

Chemistry is an often unpredictable art. See Eisai Co. v. Dr. Reddy's Labs., Ltd., 533 F.3d 1353,
1359 (Fed. Cir. 2008); see also Sannofi-Synthelabo v. Apotex, Inc., 470 F.3d 1368, 1379 (Fed.
Cir. 2006) (referring to the "unpredictability of salt formation"). Neither the expert testimony
presented to the Court, nor the prosecution history, demonstrates that a POSA at the time of the
invention would have expected that the starting ratio would have automatically and unavoidably
produced a particular outcome. (See, e.g., Tr. ·at 87 (Sunovion expert testifying that "[y]ou

expect that using an excess, it's going to favor the one-to-one and disfavor the two-to-one")
(emphasis added); id. at 106 (counsel for Sunovion acknowledging that beginning "with a molar
deficiency ... is not the be all and end all of the conversation"); id. at 115 (Cipla expert
testifying that "one can[not] just base the product outcome [on] what the starting ratio is"); D.I.
147, Ex. A at 103 (Sunovion expert testifying that it is "possible to use [molar excess] and attain
some of the 2: 1 salt"); see also generally D.I. 146 at 5-6 (Cipla arguing persuasively, "[n]owhere
in the prosecution history did the applicants indicate or imply that the starting ratio of the

7

salbutamol and tartaric acid dictates the ratio of salbutamol cation and tartrate anion in the salt
that results from the process."))
Nor is the Court persuaded that the '984 Reissue's specification compels adoption of
Sunovion' s construction, even if Examples 1 and 6, along with Scheme A, apparently ·
contemplate a 1:1.(bitartrate) output. (See D.I. 149 at 5-7 (citing and summarizing expert
declaration and testimony))
Sunovion alternatively proposes a "compromise" construction that would read a process
limitation into the claims, requiring that the compound be produced from a molar excess of
tartaric acid, regardless of the resulting output. (See Tr. at 73) This argument largely rests on the
same purported prosecution history disclaimer as Sunovion's preferred construction and,·
therefore, fares no better.
Sunovion also emphasizes the '984 Reissue applicant's response to an obviousness
rejection over Deng, a prior art reference. There, Cipla told the Patent Office that, in contrast to
Deng, "the claimed tartrate salts ... were prepared using a molar excess of tartaric acid to

salbutamol." (D.I. 110-1 at A029-30) Cipla also represented that Deng "does not provide any
reasonable motivation for a skilled artisan to use a molar excess of tartaric acid to salbutamol
(which is against the teachings of Deng) because diastereoisomeric salt formation is
unpredictable ... and Deng teaches a molar excess of albuterol to the resolving agent(s).-" (Id. at
A030) Cipla was apparently seeking to distinguish Deng's use of "expensive" and single-use
tartaric acid derivatives and its formation of an "inclusion complex." (Id.) Cipla's statements
regarding its use of a molar excess appear to be tied to its explanations about the unpredictability
of "diastereoisomeric salt formation." (Id. at A030-31) Hence, it is not "clear that the process~'
8

limitation Sunovion insists be included in the Court's construction is "an essential part of the
claimed invention." Andersen Corp. v. Fiber Composites, LLC, 474 F.3d 1361, 1375 (Fed. Cir.
2007) (emphasis added). 5
Thus, the Court will adopt Cipla' s proposed construction of these claim terms.
B.

"pure and isolated" 6

Cipla
"A tartrate salt that is substantially free of any impurities"
Sunovion
"A resolution intermediate that is converted to (R) salbutamol substantially free of the (S)
enantiomer that may further optionally be converted to a pharmaceutically acceptable salt of
(R) salbutamol"
Court
"A tartrate salt that is substantially free of any impurities"
Sunovion, again pointing to the prosecution history, contends that Cipla is "estopped from
attempting to extend its claims to any salt that is not used as an intermediate in a resolution
method." (D.I. 94 at 15 (emphasis omitted)) Cipla responds that the '984 Reissue "was filed for
the purpose of obtaining product claims, as compared to the process claims of the original
patent," and that Sunovion "impermissibly seek[ s] to import process limitations into these
product claims." (D.I. 90 at 1) The Court agrees with Cipla that this claim term does not
exclude final products from the scope of the asserted claims.

5

Sunovion contends that the Court's adoption of Cipla's construction "would cause Cipla
to violate the rule ofrecapture." (D.I. 149 at 17 n.5) Generally, "[w]hether ... broadened claims
are invalidated by the recapture rule is an issue separate from construction." MBO Labs., Inc. v.
Becton, Dickinson & Co., 474 F.3d 1323, 1332 (Fed. Cir. 2007). The instant case is not one in
which "available techniques of construction yield two possible interpretations of a reissue claim,
only one of which includes previously surrendered matter." Id. at 1332 n.3.
6

This term appears in all asserted claims (9, 10, 17, and 18) of the '984 Reissue.
9

Cipla admits that it referred to its claimed salts as "intermediates" during prosecution.

(See D.I. 146 at 11-12; see also D.I. 110-1 at A052-53) But the applicant did not clearly and
unmistakably rely on that characterization in distinguishing Deng. (See generally D.I. 149 at 1920 (quoting D.I. 90 at 11)) When Cipla amended its claims to introduce the "pure and isolated"
language, it explicitly represented to the examiner that it was doing so to address the
"concern ... that optically pure (R)-salbutamol-(L)-tartrate salt and (S)-salbutamol-(D)-tartrate
salts could be inherently present in the resolution mixtures of Deng even if they ... cannot be
isolated in pure form." (D.I. 110-1 at A053)
Sunovion points to a later amendment in which Cipla again distinguished Deng on the
basis that "Deng fails to teach or suggest ... isolation of an (R)-salbutamol-L-tartrate salt as an
intermediate to making optically pure (R)-salbutamol." (D.I. 94 at 8 (quoting D.I. 110-1 at
A070)) Having considered the full context, the Court is not persuaded that there was a clear and
unmistakable disavowal of claim scope. (See, e.g., D.I. 110-1 at A071 ("Deng clearly states a
preference for choosing a particular resolving agent (i.e., D- for (R)-salbutamol and L- for (S)salbutamol), and that preference is diametrically opposed to what is disclosed in the present
application."); '984 Reissue at 8:56-59)
In sum, the Court does not view Cipla' s references to its salts as intermediates as a clear
and unmistakable disavowal with any relationship to the term "pure and isolated." Accordingly,
the Court will adopt Cipla' s proposed construction.

10

C.

"in crystalline form" 7

Cipla
Plain and ordinary meaning or
"Having the structure of a crystal"

Sunovion
Plain and ordinary meaning (in the '984 Reissue) and
.,

Having the structure of a crystal as specified therein (in the '310 patent)

Court
"having the structure of a crystal"
Sunovion contends that "no structure of any crystal was ever described in the '984
Reissue or related prosecution history" and that a person of ordinary skill in the art would
understand "any crystalline form claimed in the '984 Reissue to refer to a crystalline form of a
1:1 bitartrate salt," in contrast to Sunovion's '310 patent. (D.I. 149 at 21-22) Claim 10 of the
'984 Reissue was copied from the '310 patent, but the Patent Office did not declare an
interference. (See D.I. 110-1 at AOOl-02)
The Court has already rejected Sunovion's attempt to limit the scope_ of the asserted
claims to 1: 1 bitartrate salts. The Court further agrees with Cipla that "crystalline form" is a
known term in the art; the '984 Reissue's specification refers to tartrate salt "crystals" and
crystallization. (E.g., '984 Reissue at 6:35, 7:31) Construction of this term as used in the '984
Reissue is not controlled by how the term is used in Sunovion's '310 patent. Although Cipla
proposed an interference proceeding, no interference was ever declared. (See generally D.I. 1101 atAOOl-09)

7

This term appears in claim 10 of the '984 Reissue.
11

Accordingly, the Court will adopt Cipla's proposed construction.

D.

"pharmaceutically acceptable salt" 8

Cipla
No construction required
Sunovion
"A final product of the originally claimed processes, excluding an intermediate of a
levalbuterol salt, that is formed after a conversion step"
Court
No construction
Because this term does not appear in any claim of the '984 Reissue, the Court declines to
construe it. The Court is not persuaded by Sunovion's insistence that construction is required;
instead, construction of this term does not appear to be necessary to resolve any dispute between
the parties.

III.

CONCLUSION
The Court construes the disputed terms as explained above. An appropriate Order

follows.

8

This term appeared in original claim 8, which "forms no part of' the '984 Reissue. (See
'984 Reissue at 1:5-9; 8:16-19)
12