Merck Sharp & Dohme B.v., Merck Sharp & Dohme, LLC v. Aurobindo Pharma USA, Inc., Aurobindo Pharma Ltd., Usv Private Limited, Gland Pharma…

United States Court of Appeals
for the Federal Circuit
______________________
MERCK SHARP & DOHME B.V., MERCK SHARP &
DOHME, LLC,
Plaintiffs-Appellees
v.
AUROBINDO PHARMA USA, INC., AUROBINDO
PHARMA LTD., USV PRIVATE LIMITED, GLAND
PHARMA LIMITED, MANKIND PHARMA LTD.,
LIFESTAR PHARMA LLC, FRESENIUS KABI USA,
LLC, DR. REDDY'S LABORATORIES, INC., DR.
REDDY'S LABORATORIES, LTD., SUN
PHARMACEUTICAL INDUSTRIES, INC., SUN
PHARMACEUTICAL INDUSTRIES LIMITED,
SANDOZ INC., LEK PHARMACEUTICALS, D.D.,
MYLAN API US LLC, MYLAN PHARMACEUTICALS
INC., MYLAN INC., EUGIA PHARMA SPECIALTIES
LIMITED,
Defendants-Appellants
LUPIN LTD., LUPIN PHARMACEUTICALS, INC.,
LUPIN INC., TEVA PHARMACEUTICALS USA,
INC.,
Defendants
______________________
2023-2254
______________________
Appeal from the United States District Court for the
District of New Jersey in Nos. 2:20-cv-02576-CCC-LDW,
2:20-cv-02750-CCC-MF, 2:20-cv-02751-CCC-MF, 2:20-cv-
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MERCK SHARP & DOHME B. V. v. AUROBINDO PHARMA USA, INC. 2
02786-CCC-MF, 2:20-cv-02787-CCC-MF, 2:20-cv-02892-
CCC-MF, 2:20-cv-02909-CCC-MF, 2:20-cv-02964-CCC-MF,
2:20-cv-03007-CCC-MF, 2:20-cv-03068-CCC-MF, 2:20-cv-
03072-CCC-MF, 2:20-cv-03112-CCC-MF, 2:20-cv-03117-
CCC-MF, 2:20-cv-03270-CCC-MF, 2:20-cv-03314-CCC-MF,
2:20-cv-03795-CCC-MF, Judge Claire C. Cecchi.
______________________
Decided: March 13, 2025
______________________
D AVID M. K RINSKY , Williams & Connolly LLP, Wash-
ington, DC, argued for plaintiffs-appellees. Also repre-
sented by S TANLEY E. F ISHER, SHAUN P ATRICK MAHAFFY ,
ASHWIN SHANDILYA; S HAYNA S. COOK, ALAN ERNST
L ITTMANN, D OUG J. WINNARD, Goldman Ismail Tomaselli
Brennan & Baum LLP, Chicago, IL; SARAH G EERS , Jones
Day, New York, NY; ANTHONY I NSOGNA, San Diego, CA;
ANDREA WEISS J EFFRIES , Los Angeles, CA.
ERIC T HOMAS WERLINGER , Katten Muchin Rosenman
LLP, Washington, DC, argued for all defendants-appel-
lants. Defendants-appellants Mylan API US LLC, Mylan
Pharmaceuticals Inc., Mylan Inc. also represented by
T IMOTHY H. G RAY ; J OSEPH J ANUSZ, J ITENDRA MALIK, Char-
lotte, NC; D EEPRO MUKERJEE , L ANCE S ODERSTROM , New
York, NY BRIAN S ODIKOFF , Chicago, IL; MATTHEW
G REINERT , Mylan, Canonsburg, PA.
MAUREEN D ONOVAN Q UELER , Office of the Solicitor,
United States Patent and Trademark Office, Alexandria,
VA, argued for amicus curiae Coke Morgan Stewart. Also
represented by SARAH E. CRAVEN, AMY J. N ELSON,
F ARHEENA Y ASMEEN RASHEED.
T IMOTHY H. K RATZ, Kratz & Barry LLP, Atlanta, GA,
for defendants-appellants Aurobindo Pharma USA, Inc.,
Aurobindo Pharma Ltd., Eugia Pharma Specialties
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MERCK SHARP & DOHME B. V. v. AUROBINDO PHARMA USA, INC. 3
Limited. Also represented by G EORGE BARRY , III; MICHAEL
P ATRICK H OGAN, Philadelphia, PA; R T OUHEY MYER, Wil-
mington, DE.
ROBERT F LORENCE, Parker Poe Adams & Bernstein
LLP, Atlanta, GA, for defendant-appellant USV Private
Limited. Also represented by T ASNEEM D HARAMSI, Green-
ville, SC; ELIZABETH CROMPTON, Washington, DC.
I MRON T. ALY , ArentFox Schiff LLP, Chicago, IL, for de-
fendant-appellant Gland Pharma Limited. Also repre-
sented by K EVIN MICHAEL N ELSON; MATTHEW T HOMAS
WILKERSON.
D MITRY SHELHOFF , Shelhoff Canfield & Chin LLC,
Short Hills, NJ, for defendants-appellants Mankind
Pharma Ltd., Lifestar Pharma LLC. Also represented by
K ENNETH C ANFIELD; J ULIA S. K IM , EDWARD D. P ERGAMENT ,
Pergament & Cepeda LLP, Florham Park, NJ.
BRIAN T IMOTHY B URGESS , Goodwin Procter LLP, Wash-
ington, DC, for defendants-appellants Fresenius Kabi
USA, LLC, Dr. Reddy's Laboratories, Inc., Dr. Reddy's La-
boratories, Ltd., Sandoz Inc., Lek Pharmaceuticals, d.d.
Also represented by N ATASHA ELISE D AUGHTREY , Los An-
geles, CA; WILLIAM EVANS , ROBERT F REDERICKSON, III,
EMILY L. RAPALINO, D ARYL L. WIESEN, Boston, MA.
CHARLES B. K LEIN, Winston & Strawn LLP, Washing-
ton, DC, for defendants-appellants Sun Pharmaceutical In-
dustries, Inc., Sun Pharmaceutical Industries Limited.
Also represented by JOVIAL W ONG.
______________________
Before D YK, MAYER , and REYNA, Circuit Judges.
D YK, Circuit Judge.
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MERCK SHARP & DOHME B. V. v. AUROBINDO PHARMA USA, INC. 4
This case concerns patent term extensions (“PTEs”) for
reissued patents under the Hatch-Waxman Act. The
Hatch-Waxman Act provides a process for extending pa-
tent terms by up to five years to compensate patent owners
for time lost during the lengthy regulatory review of new
drug applications. See 35 U.S.C. § 156. The formula for
calculating PTE is set forth in subsection 156(c), which pro-
vides that “[t]he term of a patent . . . shall be extended by
the time equal to the regulatory review period . . . oc-
cur[ring] after the date the patent is issued.” Id. § 156(c)
(emphasis added). The sole issue on appeal is whether PTE
for a reissued patent should be calculated based on the is-
sue date of the original patent or the reissued patent; in
other words, whether the reference to “the patent” in sub-
section 156(c) is to the original patent or the reissued pa-
tent. Using the issue date of the reissued patent would
usually result in shorter PTE because review that occurs
before the issue date does not affect PTE.
Here, the United States Patent and Trademark Office
(“PTO”) granted an application for a five-year PTE for a re-
issued patent, U.S. Patent No. RE44,733 (the
“RE’733 patent”), based on the issue date of the original pa-
tent, U.S. Patent No. 6,670,340 (the “’340 patent). We hold
that, in the context of reissued patents, the reference to
“the patent” in subsection 156(c) is to the original patent.
Here, the ’340 patent included claims directed to the active
ingredient for a drug product (and the RE’733 patent re-
tained those same claims). Under these circumstances, the
RE’733 patent was entitled to a five-year PTE based on the
’340 patent’s issue date, since regulatory review effectively
prevented the patent owner from enforcing the patent dur-
ing that period. We thus affirm the district court’s holding
that the PTO correctly calculated the RE’733 patent’s PTE.
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MERCK SHARP & DOHME B. V. v. AUROBINDO PHARMA USA, INC. 5
BACKGROUND
I
The material facts of this case are not in dispute.
Plaintiff-Appellee Merck1 owned the ’340 patent, which is-
sued on December 30, 2003. The ’340 patent was directed
to a class of 6-mercapto-cyclodextrin derivatives. Claim 4
is exemplary:
A 6-mercapto-cyclodextrin derivative according to
claim 1 selected from the group consisting of:
6-per-deoxy-6-per-(2-carboxyethyl)thio-γ-cy-
clodextrin;
6-per-deoxy-6-per-(3-carboxypropyl)thio-γ-cy-
clodextrin;
6-per-deoxy-6-per-(4-carboxyphenyl)thio-γ-cy-
clodextrin;
6-per-deoxy-6-per-(4-carboxyphenylme-
thyl)thio-γ-cyclodextrin;
6-per-deoxy-6-per-(2-carboxypropyl)thio-γ-cy-
clodextrin; and
6-per-deoxy-6-per-(2-sulfoethyl)thio-γ-cy-
clodextrin;
or a pharmaceutically acceptable salt thereof.
’340 patent, col. 20 ll. 51–64 (emphasis added). On
April 13, 2004, four months after the ’340 patent issued,
Merck applied to the Food and Drug Administration
(“FDA”) for approval of 6-per-deoxy-6-per-(2-carboxy-
ethyl)thio-γ-cyclodextrin (“sugammadex”). Sugammadex
1 Throughout this opinion, “Merck” refers to Merck
Sharp & Dohme B.V. and Merck Sharpe & Dohme LLC as
well as their predecessors-in-interest.
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MERCK SHARP & DOHME B. V. v. AUROBINDO PHARMA USA, INC. 6
is the active ingredient in BRIDION®, a drug that is ad-
ministered as an intravenous injection to reverse neuro-
muscular blockade, a form of paralysis induced by
rocuronium bromide and vecuronium bromide in certain
types of surgery.
While regulatory review was pending, Merck filed an
application with the PTO to reissue the ’340 patent. The
reissue application retained the original claims of the
’340 patent and included narrower claims directed specifi-
cally to sugammadex.2 On January 28, 2014, the ’340 pa-
tent was reissued as the RE’733 patent, retaining the
’340 patent’s original claims and adding twelve additional,
narrower claims relating to sugammadex. Claim 21 is ex-
emplary of the new claims:
A method for reversal of drug-induced neuromus-
cular block in a subject, which comprises parenter-
ally administering to said subject an effective
amount of 6-per-deoxy-6-per-(2-carboxyethyl)thio-
γ-cyclodextrin, sodium salt.
RE’733 patent, col. 22 ll. 29–32. None of the ’340 patent’s
nine original claims was cancelled.
The regulatory review process continued until Decem-
ber 15, 2015, when sugammadex was approved. Merck
thus could not market sugammadex for nearly twelve years
of the ’340 patent’s original term, which was set to expire
on January 27, 2021.3 On February 10, 2016, Merck filed
2 Merck filed this application after this court clari-
fied that the addition of narrower claims may constitute a
proper basis for seeking reissue, see In re Tanaka, 640 F.3d
1246, 1251 (Fed. Cir. 2011).
3 The ’340 patent’s application filing date was No-
vember 23, 2000, corresponding to an original expiration
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MERCK SHARP & DOHME B. V. v. AUROBINDO PHARMA USA, INC. 7
a PTE application for the RE’733 patent, seeking the max-
imum five-year PTE based on the ’340 patent’s original is-
sue date. On February 4, 2020, the PTO granted a five-
year PTE to the RE’733 patent based on the ’340 patent’s
original issue date: “Since the regulatory review period for
BRIDION® began on April 13, 2004, which is after the De-
cember 30, 2003[,] date of issuance for the ’340 patent, the
entire regulatory review period has been considered in the
above determination of the [PTE] length[.]” J.A. 6815. The
RE’733 patent’s expiration date was accordingly shifted
from January 27, 2021, to January 27, 2026.
II
From January to March 2020, after the RE’733 patent
reissued and around the time the FDA granted Merck’s
PTE application, Defendants-Appellants (collectively “Au-
robindo”)4 filed Abbreviated New Drug Applications (“AN-
DAs”) with the FDA to obtain approval to sell generic
versions of BRIDION®. Aurobindo submitted a Para-
graph IV certification under 21 U.S.C.
date, without any extensions or adjustments, of Novem-
ber 23, 2020. The patent received sixty-five days of patent
term adjustment under 35 U.S.C. § 154(b) and was thus set
to expire on January 27, 2021.
4 Separate suits were brought against the other ap-
pellants in the same district: Aurobindo Pharma USA, Inc.,
Aurobindo Pharma, Ltd., and Eugia Pharma Specialties
Ltd.; Gland Pharma Ltd.; Mankind Pharma Ltd. and
Lifestar Pharma LLC; Mylan API US LLC, Mylan Phar-
maceuticals Inc., and Mylan Inc.; Sandoz Inc., and Lek
Pharmaceuticals d.d.; Sun Pharmaceutical Industries, Inc.
and Sun Pharmaceutical Industries Ltd.; Fresenius Kabi
USA, LLC; Dr. Reddy’s Laboratories, Inc., and Dr. Reddy’s
Laboratories, Ltd.; and USV Private Ltd. These cases were
consolidated.
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MERCK SHARP & DOHME B. V. v. AUROBINDO PHARMA USA, INC. 8
§ 355(j)(2)(A)(vii)(IV) as to the RE’733 patent. A Para-
graph IV certification allows an ANDA applicant to certify,
to the best of its knowledge, that a patent that claims the
brand-name drug or use for such drug is “invalid or will not
be infringed by the manufacture, use, or sale of the new
drug for which the application is submitted.” Id. In accord-
ance with the patent statute, 35 U.S.C. § 271(e)(2)(A),
Merck treated this filing as an act of infringement and
brought suit.
At trial, Aurobindo argued that the RE’733 patent was
not entitled to a five-year PTE and had therefore expired.
It argued that the PTO erred in calculating the
RE’733 patent’s PTE based on the ’340 patent’s original is-
sue date, urging that the plain text of subsection 156(c) re-
quired the PTO to calculate PTE based on the issue date of
“the patent” for which PTE was sought: the RE’733 patent.
According to Aurobindo, the RE’733 patent was only enti-
tled to a 686-day PTE (corresponding to an expiration date
of December 14, 2022), since “only 686 days of the 4,265-
day regulatory review period for BRIDION ® ‘occur[red] af-
ter the date the [RE’733] patent . . . issued.’” Defendants’
Opening Brief on Their Patent Term Extension Invalidity
Defense at 11, In re Sugammadex, 2023 WL 3966146
(D.N.J. June 13, 2023) (No. 20-cv-2576) (alterations in
original) (quoting 35 U.S.C. § 156(c)).
The district court disagreed, finding that Aurobindo’s
construction of subsection 156(c) would undermine the
purpose of the Hatch-Waxman Act. The district court con-
cluded that section 156 should be read in light of 35 U.S.C.
§§ 251, 252, and that “the patent” in subsection 156(c)
must refer to the original patent, not the reissued patent.
See In re Sugammadex, No. 20-cv-2576, 2023 WL 3966146,
at *15–16 (D.N.J. June 13, 2023). Based on this
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MERCK SHARP & DOHME B. V. v. AUROBINDO PHARMA USA, INC. 9
construction, the district court held that the RE’733 patent
was entitled to a five-year PTE.5
Aurobindo appealed. We have jurisdiction pursuant to
28 U.S.C. § 1295(a)(1). On January 19, 2024, the PTO filed
an amicus brief in support of affirmance. We invited the
PTO to present oral argument.
D ISCUSSION
Statutory construction is a question of law that is re-
viewed de novo. Hawkins v. United States, 469 F.3d 993,
1000 (Fed. Cir. 2006). Statutory construction begins “with
the language of the statute itself,” United States v. Ron
Pair Enters., Inc., 489 U.S. 235, 241 (1989), bearing in
mind that “[s]tatutory language cannot be construed in a
vacuum,” Sturgeon v. Frost, 577 U.S. 424, 438 (2016) (in-
ternal citation and quotation marks omitted). The “[i]nter-
pretation of a word or phrase depends upon reading the
whole statutory text, considering the purpose and context.”
Dolan v. U.S. Postal Serv., 546 U.S. 481, 486 (2006).
The question on appeal is not, as the parties sometimes
suggest, the meaning of the term “issue.” Aurobindo is
clearly correct that the date the reissued patent issues is
the date of reissue (here, January 28, 2014). Rather, this
5 The district court held a one-day bench trial in
which expert witnesses testified as to the practices of the
PTO in granting PTEs for reissued patents for the purpose
of establishing an agency practice that may be entitled to
deference. Sugammadex, 2023 WL 3966146, at *2. This
was improper, since agency practice is determined by ex-
amining agency orders, not by the testimony of expert wit-
nesses. Rumsfeld v. United Techs. Corp., 315 F.3d 1361,
1369 (Fed. Cir. 2003). This error has no impact on this ap-
peal.
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MERCK SHARP & DOHME B. V. v. AUROBINDO PHARMA USA, INC. 10
case requires us to determine the meaning of the term “the
patent” as used in subsection 156(c):
The term of a patent eligible for extension under
subsection (a) shall be extended by the time equal
to the regulatory review period for the approved
product which period occurs after the date the pa-
tent is issued[.]
35 U.S.C. § 156(c) (emphasis added).
Aurobindo argues that, under the text’s plain meaning,
“the patent” refers to the reissued patent, since “the ‘patent
eligible for extension’ is the [reissued] patent.” Appellant’s
Br. 23 (quoting 35 U.S.C. § 156(c)). This is because “the
reissue[d] patent is distinct from the original patent[,]
[and] the latter ceases to exist on the date the former is
issued.” Id. at 27 (emphasis removed). Merck urges the
opposite interpretation, arguing that subsection 156(c)’s
“text, together with other patent statutes and the history
of patent reissue, demonstrate that [subs]ection 156(c) re-
fers to the original issue date.” Appellee’s Br. 17 (emphasis
removed). We agree with Merck that the reference to “the
patent” in subsection 156(c) refers to the original patent di-
rected to a drug product.6
As the PTO points out, the language of subsec-
tion 156(c) standing alone is ambiguous. It is unclear
whether “the patent” refers to the original or reissued pa-
tent. Because “[w]e cannot say that [this language] is alto-
gether free of ambiguity,” we “consider statutory text and
context together.” Caraco Pharm. Lab’ys, Ltd. v. Novo
6 PTE is available for patents that contain drug
product claims, method of using drug product claims, and
method of manufacturing drug product claims. 35 U.S.C.
§ 156(b). This opinion collectively refers to these claims as
claims “directed to a drug product.”
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MERCK SHARP & DOHME B. V. v. AUROBINDO PHARMA USA, INC. 11
Nordisk A/S, 566 U.S. 399, 412 (2012); accord Chapman v.
Hous. Welfare Rights Org., 441 U.S. 600, 608 (1979). The
Supreme Court in Caraco provided important guidance for
interpreting another provision of the Hatch-Waxman Act
where, as here, the plain text of the statute was ambiguous.
In Caraco, the Court considered the meaning of a pro-
vision authorizing an ANDA applicant sued for patent in-
fringement to bring a counterclaim “on the ground that the
patent does not claim . . . an approved method of using the
drug.” 566 U.S. at 413 (alteration in original) (quoting 21
U.S.C. § 355(j)(5)(C)(ii)(I)). The patentee urged that “not
an” meant “not any,” such that an ANDA applicant could
only bring this challenge if the patent did not claim any
approved method of using the drug at all. See id. The
ANDA applicant urged that “not an” meant “not a particu-
lar one,” such that this challenge was available if the pa-
tent did not claim one of the methods of use for which the
ANDA applicant sought to market the drug. See id. Rec-
ognizing that the meaning of “not an” was ambiguous, the
Court looked to the broader “statutory context,” explaining
that “Congress understood[] [that] a single drug may have
multiple methods of use” and concluded that “[t]he statu-
tory scheme . . . contemplates that one patented use will
not foreclose marketing a generic drug for other unpat-
ented ones.” Id. at 414–15. The Court concluded that “not
an” must refer to “not a particular one” as suggested by the
ANDA applicant because “[w]ithin [the Hatch-Waxman
Act’s] framework, the counterclaim naturally functions to
challenge the brand’s assertion of rights over whichever
discrete use (or uses) the generic company wishes to pur-
sue.” Id. at 415. This was “because Congress meant (as it
usually does) for the provision it enacted to fit within the
statutory scheme.” Id. at 416.
So, too, here, we must interpret the term “the patent”
with reference to “the specific context in which that lan-
guage is used, and the broader context of the statute as a
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MERCK SHARP & DOHME B. V. v. AUROBINDO PHARMA USA, INC. 12
whole.” Robinson v. Shell Oil Co., 519 U.S. 337, 341 (1997);
see also Dep’t of Homeland Sec. v. MacLean, 574 U.S. 383,
393 (2015) (rejecting an interpretation that “could defeat
the purpose of the . . . statute”); Centripetal Networks, Inc.
v. Cisco Sys., Inc., 38 F.4th 1025, 1031 (Fed. Cir. 2022) (ex-
plaining that in interpreting a statute, we “look to the pro-
visions of the whole law, and [] its object and policy”
(quoting Dole v. United Steelworkers of Am., 494 U.S. 26,
35 (1990)).
While Congress does not appear to have contemplated
the situation presented by reissued patents in drafting sec-
tion 156, the purpose of the section is clear: to compensate
pharmaceutical companies for the effective truncation of
their patent terms while waiting for regulatory approval of
new drug applications. See H.R. Rep. No. 98-857, pt. 1,
at 15 (1984) (stating that the purpose of PTE is to “create
a new incentive for increased expenditures for research
and development,” where “[t]he incentive is the restoration
of some of the time lost on patent life while the patent is
awaiting pre-market approval” (emphasis added)); Drug
Price Competition and Patent Term Restoration Act of
1984: Hearing on S. 2748 Before the S. Comm. on Lab. &
Hum. Res. of the U.S. Senate at 2, 98th Cong. 1102 (1984)
(statement of Sen. Orrin Hatch) (“The added research and
development will flow from added patent protection which
will compensate the research drug companies for the years
of exclusive marketing time under their patents lost be-
cause of the lengthy FDA testing and review period.”).
We have recognized that the purpose of the Hatch-
Waxman Act is to “provid[e] patent holders with limited
extensions of patent term in order to recover a portion of
the market exclusivity lost during the lengthy process of
development and FDA review.” Glaxo, Inc. v. Novopharm,
Ltd., 110 F.3d 1562, 1568 (Fed. Cir. 1997); see also Merck
& Co. v. Hi-Tech Pharmacal Co., 482 F.3d 1317, 1323
(Fed. Cir. 2007); PhotoCure ASA v. Kappos, 603 F.3d 1372,
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MERCK SHARP & DOHME B. V. v. AUROBINDO PHARMA USA, INC. 13
1374 (Fed. Cir. 2010). In particular, “[t]he statute contem-
plates a patentee receiving time lost in its patent term by
reason of FDA delay, and the statute should be liberally
interpreted to achieve this end.” Merck & Co. v. Kessler,
80 F.3d 1543, 1552 (Fed. Cir. 1996).
We conclude that, in the context of reissued patents,
the Hatch-Waxman Act contemplates PTE for those pa-
tents and only those patents with claims directed to drug
products whose period of exclusivity was delayed by FDA
review.7 That purpose applies in this case, since constru-
ing “the patent” in subsection 156(c) as the original patent
compensates Merck for the period of exclusivity lost due to
regulatory delay. On the other hand, Aurobindo’s construc-
tion denies Merck compensation for all but a small period
of the delay. There is no reason why the Hatch-Waxman
Act’s purpose would be served by disabling extensions of
the unexpired term solely based on a patent holder’s deci-
sion to seek reissue, and Aurobindo offers none.8
Aurobindo, however, urges that “the patent” cannot re-
fer to the original patent because the original patent is
7 We note that the Hatch-Waxman Act was passed
prior to the Uruguay Round Agreements Act, so the pa-
tent’s expiration date was based on the issue date rather
than the filing date. This does not change our analysis,
since any period of regulatory review that occurs after the
patent’s issue date still disables the patent owner from
commercially marketing the drug product during the life-
time of the patent.
8 At oral argument, when asked why Congress would
intend for a patent owner to lose PTE simply by seeking
reissue, counsel for the defendants replied: “If the text is
plain that’s it. There might be policy reasons for why the
statute might have been written differently, but that is for
Congress to determine.” Oral Arg. at 2:01–08.
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MERCK SHARP & DOHME B. V. v. AUROBINDO PHARMA USA, INC. 14
“dead” upon reissue. Appellant’s Br. 26 (quoting Seattle
Box Co. v. Indus. Crating & Packing, 731 F.2d 818, 827
(Fed. Cir. 1984)); see also Eby v. King, 158 U.S. 366, 373
(1895) (holding that a patent owner may not rely on the
original patent after the reissued patent is declared void
because the original patent “is extinguished” (quoting Peck
v. Collins, 103 U.S. 660, 664 (1880)); Moffitt v. Garr,
66 U.S. 273, 282–83 (1861) (holding that a suit for infringe-
ment of the original patent brought before the issuance of
the reissued patent must “fail” because “[a] surrender of
the patent [for reissue] . . . extinguishes the patent”). But
whether the holder of the reissued patent has an enforcea-
ble right in the original patent’s claims is irrelevant, since
the reissued patent inherits “the unexpired part of the term
of the original patent,” 35 U.S.C. § 251(a), which now un-
ambiguously “begin[s] on the date on which the patent is-
sues and end[s] 20 years from the date on which the
application for the patent was filed,” id. § 154(a)(2), subject
to patent term adjustment (not at issue in this case). Sec-
tion 156 is designed to extend the term of the original pa-
tent, not to make the original patent enforceable after
reissue. We have explained that a “reissue patent does not
simply replace an original patent nunc pro tunc.” Intel
Corp. v. Negotiated Data Sols., Inc., 703 F.3d 1360, 1364
(Fed. Cir. 2012). We accordingly conclude that Aurobindo’s
argument is foreclosed by the both the purpose of sec-
tion 156 and related statutory context.
The only construction that comports with the purpose
of the Hatch-Waxman Act is one that extends PTE to pa-
tent owners who were actually disabled from benefiting
from patent protection during the pendency of regulatory
review. We thus conclude that, in the context of reissued
patents, “the patent” in subsection 156(c) refers to the orig-
inal patent. A reissued patent is entitled to PTE based on
the original patent’s issue date where, as here, the original
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MERCK SHARP & DOHME B. V. v. AUROBINDO PHARMA USA, INC. 15
patent included the same claims directed to a drug product
subject to FDA review.9
9 We do not find the parties’ reliance on section 251
to be helpful, since it does not shed any light on the mean-
ing of the term “the patent.” We are also not persuaded by
Merck’s reliance on language in section 252 providing that
that “every reissued patent shall have the same effect and
operation in law, on the trial of actions for causes thereaf-
ter arising, as if the same had been originally granted in
such amended form.” According to Merck, the “point of this
clause” is to “backdat[e] reissued patents to the original pa-
tent date for assessing litigation defenses.” Appellee’s
Br. 31.
While we agree that section 252 applies to assessing
litigation defenses, we think the more plausible reading of
section 252 is to backdate reissued patents to the original
priority dates and critical dates of the original patents for
the purpose of assessing defenses such as anticipation and
obviousness. See Fresenius USA, Inc. v. Baxter Int’l, Inc.,
721 F.3d 1330, 1337 (Fed. Cir. 2013) (“[T]his change was
meant ‘simply to correct an almost unbelievable and ineq-
uitable situation. . . . [that] if a patentee applies for a reis-
sue, no matter for what purpose, all rights he had in and
under the original patent are forfeited ab initio upon the
grant of the reissue.’” (quoting S. Rep. No. 71-567, at 1)).
Merck’s reliance on language that provides that reis-
sued claims that are “substantially identical” to the claims
in an originally patent “shall . . . have effect continuously
from the date of the original patent” is similarly misplaced.
The purpose of this provision is to clarify that a patent
owner cannot enforce reissued claims before the reissued
patent issues unless those claims are substantially identi-
cal to the original patent’s claims. See Seattle Box,
731 F.2d at 827 (“Congress, in this statute, has explicitly
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MERCK SHARP & DOHME B. V. v. AUROBINDO PHARMA USA, INC. 16
Our reading of subsection 156(c) is further confirmed
by other statutory provisions of the Patent Act. Subsec-
tion 156(a) provides that “the term of a patent . . . shall be
extended . . . from the original expiration date of the pa-
tent.” 35 U.S.C § 156(a) (emphasis added). The most nat-
ural reading of this language is that “the patent” must be
the original patent, since the “original expiration date” is
tied to the filing date of the original patent, not the reissued
patent. Subsection 154(a)(2) now provides that a patent’s
term “begin[s] on the date on which the patent issues and
end[s] 20 years from the date on which the application for
the patent was filed.” The reference to “the patent” here
must be to the original patent, not the reissued patent,
which inherits the original patent term.10
While not binding, we note that the PTO has also re-
vised its Manual of Patent Examining Procedure in a man-
ner that substantially tracks with our analysis as applied
in this case. It has been revised to provide that “[w]ith re-
spect to calculating the amount of extension to which the
reissued patent is entitled to receive, so long as the original
patent claimed the approved product and the reissued pa-
tent claims the approved product, the original patent grant
date would be used to calculate the extension to which the
reissued patent would be entitled.” MPEP § 2766. This
limited claim continuity to claims in the reissued patent
identical to claims in the original patent.”) We find no ba-
sis to conclude that Congress intended for this provision to
apply outside the context of backdating priority dates.
10 If the original patent included claims directed to a
drug product subject to regulatory review and the patent
owner subsequently cancels those claims, section 156 of
course would not apply, whether the cancellation occurred
before or after regulatory review. This is because cancelled
claims are treated as void ab initio. Fresenius, 721 F.3d
at 1346.
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MERCK SHARP & DOHME B. V. v. AUROBINDO PHARMA USA, INC. 17
comports with the statutory scheme of the Hatch-Waxman
Act, which is to award PTE only in those circumstances in
which the patent owner is prevented from enjoying patent
protection because of the pendency of regulatory review.11
CONCLUSION
We conclude that in the context of reissued patents,
“the patent” in subsection 156(c) refers to the original pa-
tent that includes claims that are directed to a drug prod-
uct. Because the ’340 patent included claims directed to
sugammadex and was issued before FDA approval of
BRIDION®, we agree with the district court that the
RE’733 reissue patent was entitled to the five-year PTE
based on the ’340 patent’s issue date.
AFFIRMED
11 Difficult questions arise in cases where the original
patent did not include any claims directed to the drug prod-
uct and was later reissued to include broader claims di-
rected to such products. In such cases, a patent owner may
or may not have had the opportunity to enforce the patent
during review depending on whether the reissued patent
was issued before or after regulatory review. Those ques-
tions are not presented by this case.
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