Amicus Curiae Brief — MSN Pharmaceuticals, Inc., et al., Petitioners v. Novartis Pharmaceuticals Corporation

No. 25-225

IN THE

MSN PHARMACEUTICALS, INC., ET AL.,

Petitioners,

v.

NOVARTIS PHARMACEUTICALS CORPORATION,

Respondent.

ON PETITION FOR A WRIT OF CERTIORARI

TO THE UNITED STATES COURT OF APPEALS

FOR THE FEDERAL CIRCUIT

BRIEF OF BIOPHORE PHARMA INC.; NATCO PHARMA

INC.; DEVA HOLDING A/S

AS AMICUS CURIAE IN SUPPORT OF PETITIONERS

SHASHANK UPADHYE

Counsel of Record

UPADHYE TANG LLP

109 Symonds Dr. #174

Hinsdale, IL 60522

(312) 327-3326

shashank@ipfdalaw.com

Counsel for Amicus Curiae

October 8, 2025

i

TABLE OF CONTENTS

Page

INTEREST OF AMICI CURIAE ................................ 1

INTRODUCTION & SUMMARY OF THE

ARGUMENT ............................................................... 1

ARGUMENT ............................................................... 4

I.

If An Invention Is Described By The Claims,

Then That Invention Must, Under Section

112, Be Described In The Patent

Specification. .................................................. 4

A. Inventions are Described the Claims. .... 4

B. The Claimed Invention Must Comply

With Section 112(a) ................................. 5

II. If One Cannot Expressly Claim The After

Arising Technology Because It Runs Afoul

With Section 112(a), Then Axiomatically It

Runs Afoul With Section 112(a) For

Infringement Purposes. ................................. 7

III. To The Extent An Intra-Circuit Split Exists,

This Court Should Resolve This Split. ........... 9

CONCLUSION .......................................................... 12

ii

TABLE OF AUTHORITIES

Page(s)

Cases

Amgen Inc. v. Hoechst Marion Roussel,

Inc.,

314 F.3d 1313 (Fed. Cir. 2003) .............................. 8

Amgen Inc. v. Sanofi,

598 U.S. 594 (2023) .......................................... 5, 10

Bilski v. Kappos,

561 U.S. 593 (2010) .............................................. 11

Chiron Corp. v. Genentech, Inc.,

363 F.3d 1247 (Fed. Cir. 2004) .............................. 9

Festo Corp. v. Shoketsu Kinzoku Kogyo

Kabushiki Co., Ltd.,

535 U.S. 722 (2002) ............................................ 6, 7

Grant v. Raymond,

31 U.S. 218 (1832) .................................................. 6

In re Hogan,

559 F.2d 595 (C.C.P.A. 1977)........................... 9, 10

Innogenetics, N.V. v. Abbott Lab’ys,

512 F.3d 1363 (Fed. Cir. 2008) .............................. 9

Nautilus, Inc. v. Biosig Instruments,

Inc.,

572 U.S. 898 (2014) .............................................. 10

iii

Plant Genetic Sys., N.V. v. DeKalb

Genetics Corp.,

315 F.3d 1335 (Fed. Cir. 2003) .............................. 9

SAS Institute, Inc. v. Iancu,

584 U.S. 357 (2018) ................................................ 8

United States v. Dubilier Condenser

Corp.,

289 U.S. 178 (1933) ................................................ 6

Univ. of Rochester v. G.D. Searle & Co.,

Inc.,

358 F.3d 916 (Fed. Cir. 2004) ................................ 5

Whittemore v. Cutter,

29 F. Cas. 1120 (C.C.D. Mass. 1813) ..................... 6

Statutes

35 U.S.C. §112 ............................................... 3, 4, 9, 10

35 U.S.C. §112(a) ............................................... 5, 7, 12

35 U.S.C. §112(b) ......................................................... 4

Hatch Waxman Act ..................................................... 2

Patent Act of 1870, § 26, 16 Stat. 201 ...................... 11

Other Authorities

Shashank Upadhye, Generic

Pharmaceutical Patent and FDA

Law (Westlaw 2024–25 ed.) ................................... 2

iv

Shashank Upadhye, The Perils of Broad

Patent Claims: From Issuance to

Invalidity, Upadhye Tang LLP (July

1, 2025), https://ipfdalaw.com/theperils-of-broad-patent-claims-fromissuance-to-invalidity/............................................ 8

INTEREST OF AMICUS CURIAE1

The amicus are generic pharmaceutical companies

that seek FDA approval for and market generic drug

products in the U.S. They are: Biophore Pharma Inc.;

Natco Pharma Inc.; and Deva Holding A/S. They have

an interest in ensuring that patent laws are robust

enough to facilitate the Constitutional requirement of

promoting the progress of industry. But underlying

the promotion of industry, is that the patent laws

must be fair; that is fairly construed to promote

competition. As generic drug companies are often

defendants in patent infringement suits, much

litigation surrounds the proper and fair interpretation

of the patent laws.

INTRODUCTION &

SUMMARY OF THE ARGUMENT

This case presents the Court with an opportunity

to clarify some fundamental principles of patent law,

with respect to the “written description” and

enablement requirements. Particularly, this case

concerns statutory interpretation, not technical or

scientific issues.

This brief explains the plain problem that needs

resolving. The following facts are not in dispute.

Novartis obtained FDA approval, on 07 July 2015, to

1 Under this Court’s Rule 37.2, amicus states that counsel of

record for all parties received notice of amicus’s intent to file this

brief more than ten days before the brief’s due date. And under

this Court’s Rule 37.6, amicus states that no counsel for a party

authored this brief in whole or in part, that no such counsel or

party made a monetary contribution intended to fund the brief’s

preparation or submission, and that no person other than amicus

and its counsel made such a monetary contribution.

2

market Entresto®, which is a complex of the

molecules: sacubitril and valsartan. The underlying

patent, the U.S. Patent No. 8,101,659 (“the ’659

patent”) claims a combination of the molecules. The

‘659 patent was filed (as a patent application) and

issued long before the FDA approved Entresto. It is

undisputed that after the ‘659 patent was filed,

Novartis then discovered that the two molecules could

be put together in a complex. By being in a complex,

the molecules, are in a sense, joined together. It would

be akin to two people almost holding hands versus

they are clasping each other’s hands. Once they are

actually holding hands, the hands are joined together.

The ’659 patent was listed in the FDA’s Orange Book

on 06 Aug. 2015.

Now

because

Entresto

was,

per

FDA

characterization, a complex of the two molecules,

generic companies that file the generic drug dossier

(called the ANDA), must have the same molecules in

the same structure. Hence MSN’s proposed generic

version must also be a complex. Again, there is no

dispute that MSN’s proposed generic version of

Entresto is a complex. If it were not, then FDA could

not approve MSN’s generic version.

MSN filed its generic drug dossier seeking

approval of its generic version. As is typical in the socalled Hatch Waxman Act ¶ IV Certification context,

MSN filed a Paragraph IV certification against the

’659 patent. Thereafter, Novartis sued MSN (among

others) for patent infringement under the Hatch

Waxman Act. The basic background of the Hatch

Waxman Act scheme is described in Shashank

Upadhye, Generic Pharmaceutical Patent and FDA, §

1:3, Legal aspects of the generic drug development

3

pathway for judges and lawyers (Westlaw 2024–25

ed.).

Novartis argued at trial during the so-called claim

construction process that the claim language of

“combination” in the ‘659 patent had to include a

complex because that would be the only way to

ensnare the MSN generic drug complex. Getting that

claim construction would make MSN liable for patent

infringement.

Be careful what you wish for, for it might come

true. The district court noted that by arguing for the

broad claim construction to ensnare an infringer, that

might lead to patent invalidity because of a lack of

written description under 35 U.S.C. §112. This was

because the “complex” of the molecules was not

described in the ’659 patent specification. Nor could it.

The complex was not discovered until years later so it

could not have been described in the ’659 patent

specification. Accordingly, the trial court invalidated

the relevant claims. It said that later-arising

technology could not be described in an earlier

specification and thus could not support the claim the

claim that encompassed later-arising technology.

The Federal Circuit reversed. Because neither

party appealed the actual claim construction, the

Court only dealt with the invalidity issue. The Court

stated that for the purposes of invalidity, after-arising

technology could not be encompassed within the

claim. And because of that, the claim construction for

invalidity purposes excluded complexes. And when it

excluded complexes, there was no need to describe

something that was not required to be described. The

Court, therefore, reversed the invalidity decision.

The problem with this construct is that case law

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squarely states that claims are to be construed the

same for infringement and for invalidity. The Court’s

ruling creates an unfair situation: for infringement a

patentee can ask the court for a broader claim

construction to ensnare the infringer through later

developed technology, but then not suffer the

consequence that such technology need not be

described in the specification.

During the underlying litigation, the ‘659 patent

expired due to its natural patent expiration. Novartis,

therefore, enjoyed the full term (including any

relevant term extensions) for the ‘659 patent. This

expiration does not moot this case because MSN

launched its generic version in the interim and could

be on the hook for monetary patent damages.

Accordingly, this Court should grant the Petition

to clarify the case law that after-arising technology, if

used for infringement purposes, then must also be

considered for invalidity purposes. By granting the

Petition, it can clarify that the In Re Hogan-Entresto

theory is not the law and should be rejected.

ARGUMENT

I.

If An Invention Is Described By The

Claims, Then That Invention Must, Under

Section 112, Be Described In The Patent

Specification.

A.

Inventions are Described the Claims.

The current patent statute, 35 U.S.C. §112(b),

requires that the invention be claimed. Indeed,

§ 112(b) requires that the claims identify what the

inventor regards as his invention. Accordingly, there

is no doubt that Novartis had to include claims to the

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invention, and that invention must be what it

regarded as its invention.

B.

The Claimed Invention Must Comply

With Section 112(a)

Even though the applicant has claimed an

invention, it is not done. The invention claimed must

also comply with the requirements of 35 U.S.C.

§ 112(a). Here, the statute commands that there must

be a written description and enablement of the

invention. And the statute commands the level of

detail required: in full, clear, concise, and exact terms.

Accordingly, scant details or missing details are not

enough. Rather, there must be a full description.

Now for after arising technology, this is where it

fails. One cannot fully, clearly, concisely, nor exactly

define what is not yet even known or discovered. The

Federal Circuit stated that the “written description

requirement serves a teaching function, as a “quid pro

quo” in which the public is given meaningful

disclosure in exchange for being excluded from

practicing the invention for a limited period of time.”

Univ. of Rochester v. G.D. Searle & Co., Inc., 358 F.3d

916, 922 (Fed. Cir. 2004). And in that case, the patent

claims directed to COX–2 inhibitors were invalidated

for lack of adequate written description because the

existence

of

such

inhibitors

was

merely

“hypothesized”; no such inhibitors were yet known

and none were described in the patent). Id. at 918,

923. Allowing yet-to-be-discovered after-arising

technology to be swept up into a claim for

infringement purposes denies the quid pro quo

requirement that the public be educated on that. That

is, how can after-arising technology be dedicated to

the public upon patent expiration if that technology is

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not even fully described in the patent specification?

Amgen Inc. v. Sanofi, 598 U.S. 594, 605 (2023) (“So

today, just as in 1790, the law secures for the public

its benefit of the patent bargain by ensuring that,

upon the expiration of [the patent], the knowledge of

the invention inures to the people, who are thus

enabled without restriction to practice it. United

States v. Dubilier Condenser Corp., 289 U.S. 178, 187

(1933); see also Grant v. Raymond, 31 U.S. 218, 219

(Marshall, C. J.) (“This is necessary in order to give

the public, after the privilege shall expire, the

advantage for which the privilege is allowed, and is

the foundation of the power to issue a patent.”);

Whittemore v. Cutter, 29 F. Cas. 1120, 1122 (No.

17,600) (C.C.D. Mass. 1813) (Story, J.) (“If therefore

[the disclosure] be so obscure, loose, and imperfect,

that this cannot be done, it is defrauding the public of

all the consideration, upon which the monopoly is

granted.”) (cleaned up).

This Court reaffirmed this principle in Festo.

There the Court reaffirmed that patent holders are

supposed to know what they own; and competitors are

entitled to know what patentees do not own. And this

comes from a full description of the invention that the

patentee knows what he owns. Festo Corp. v. Shoketsu

Kinzoku Kogyo Kabushiki Co., Ltd., 535 U.S. 722, 731

(2002) (“A patent holder should know what he owns,

and the public should know what he does not. For this

reason, the patent laws require inventors to describe

their work in full, clear, concise, and exact terms as

part of the delicate balance the law attempts to

maintain between inventors, who rely on the promise

of the law to bring the invention forth, and the public,

which should be encouraged to pursue innovations,

7

creations, and new ideas beyond the inventor's

exclusive rights.”) (cleaned up).

A patent applicant is not penalized by this

understanding. There is nothing unfair about this.

For if the applicant (or another applicant) should

invent or discover after-arising technology, nothing

stops the applicant from filing a new patent

application on that after arising technology and

obtaining new and presumably longer-term patent

protection (assuming the other aspects of the patent

laws are met). Indeed, Novartis obtained two patents

to the complex as U.S. Patent Nos.: 8,877,938; and

9,388,134.

II.

If One Cannot Expressly Claim The After

Arising Technology Because It Runs Afoul

With Section 112(a), Then Axiomatically It

Runs Afoul With Section 112(a) For

Infringement Purposes.

Suppose Novartis during the patent application

process expressly tried to claim the “complex”. That

claim would have certainly been rejected for a lack of

written description.

Now, does it make sense that a patentee can assert

a specific after-arising technological species for

infringement purposes, and win the infringement

side, yet not have been allowed that claim during the

application process? No, it does not make sense, and

it is unfair. This understanding would not provide any

notice to any competitor about what activities it might

undertake, as being in-bounds or out-of-bounds. Festo,

535 U.S. at 730–731 (“The monopoly is a property

right; and like any property right, its boundaries

should be clear. This clarity is essential to promote

8

progress”). And given that many of these claim

construction and invalidity decisions are based on

questions of law, or mixed questions of law and fact, it

would ultimately be up to the Federal Circuit panel to

decide these questions. That is, no question can be

settled until the Federal Circuit panel says so. This

will cost competitors years of litigation and millions of

dollars. Generic drug companies, who are defendants

in these pharma patent cases, seek to bring cheaper

versions of the drugs to the market for patient and

payor benefit. The millions of dollars spent and time

lost affect competition and prices. And if this is a

question of policy about fair notice to competitors

versus rewards for inventors, Congress is best suited

to resolve this. SAS Institute, Inc. v. Iancu, 584 U.S.

357, 368 (2018) (“Policy arguments are properly

addressed to Congress, not this Court. It is Congress's

job to enact policy and it is this Court's job to follow

the policy Congress has prescribed.”).

That after-arising technology can also be used for

infringement purposes (to ensnare the competitor) but

survive invalidity, upends the precedent that claims

are to be construed the same for infringement and

invalidity. Amgen Inc. v. Hoechst Marion Roussel,

Inc., 314 F.3d 1313, 1330 (Fed. Cir. 2003) (“It is

axiomatic that claims are construed the same way for

both invalidity and infringement.”).

Also, the situation of after arising technology being

used for infringement purposes but suffering

invalidity is a patentee’s own fault. It is the patentee

that argues, in the scope of litigation, that it needs a

broader claim construction to ensnare the competitor

for infringement purposes. See Shashank Upadhye,

The Perils of Broad Patent Claims: From Issuance to

9

Invalidity, Upadhye Tang LLP (July 1, 2025),

https://ipfdalaw.com/the-perils-of-broad-patentclaims-from-issuance-to-invalidity/ (“Patent owners

often advocate for broad interpretations of claim

terms in order to capture the accused product. But in

doing so, they may find themselves hoisted by their

own petard. … In their quest for litigation advantage,

patent owners may stretch claim scope just far enough

to capture the target and right into the jaws of

invalidity. The very arguments used to broaden the

claim for infringement purposes become the rope by

which the claim is hanged under §112.”).

III.

To The Extent An Intra-Circuit Split

Exists, This Court Should Resolve This

Split.

In some decisions, including In re Entresto, the

Federal Circuit has held that after-arising technology

may never invalidate a patent. See, e.g., Plant Genetic

Sys., N.V. v. DeKalb Genetics Corp., 315 F.3d 1335,

1340 (Fed. Cir. 2003) (holding that “one [can]not use

a later-existing state of the art to invalidate a patent

that was enabled for what it claimed at the time of

filing”); In re Hogan, 559 F.2d 595, 604 (C.C.P.A.

1977) (“It is quite another thing, however, to utilize

the patenting or publication of later existing

improvements to ʻreach back’ and preclude or

invalidate a patent on the underlying invention.”).

Other Federal Circuit decisions cast doubt on the

premise that after-arising technology is necessarily

unclaimed and thus may never expose a patent’s

invalidity. See, e.g., Innogenetics, N.V. v. Abbott

Lab’ys, 512 F.3d 1363, 1371–72 (Fed. Cir. 2008) (“Our

case law allows for after-arising technology to be

captured within the literal scope of valid claims that

10

are drafted broadly enough.”); Chiron Corp. v.

Genentech, Inc., 363 F.3d 1247, 1255 (Fed. Cir. 2004)

(“[T]he Chiron scientists, by definition, could not have

possession of, and disclose, the subject matter of

chimeric antibodies that did not even exist at the time

of the 1984 application. Thus, axiomatically, Chiron

cannot satisfy the written description requirement for

the new matter …”).

To the extent that In Re Hogan still represents

good law, it is not being followed by later Federal

Circuit panels. Because Federal Circuit panels are not

applying its case law consistently, patentees can and

are gaming the system. Gaming the system: (i) creates

uncertainty for industry; (ii) unpredictability because

the outcome can be Federal Circuit panel dependent;

and (iii) ultimately the U.S. public is deprived of lowcost generic drugs.

This Court has not reviewed the patent law

“written description” requirement under § 112,

though it has reviewed Federal Circuit decisions

involving the “enablement” requirement in Amgen

and the “definiteness” requirement in Nautilus. And

in both cases, this Court recognized the centuries long

history of the written description requirement.

Indeed, in Nautilus, this Court recognized that the

full written description was the basis of the patent

right; even before the statutes were amended to

include the claims. See Nautilus, Inc. v. Biosig

Instruments, Inc., 572 U.S. 898, 902 (2014) (“Under

early patent practice in the United States, we have

recounted, it was the written specification that

represented the key to the patent. Eventually,

however, patent applicants began to set out the

invention’s scope in a separate section known as the

11

‘claim.’ The Patent Act of 1870 expressly conditioned

the receipt of a patent on the inventor's inclusion of

one or more such claims, described with particularity

and distinctness. See Act of July 8, 1870, § 26, 16 Stat.

201 (to obtain a patent, the inventor must particularly

point out and distinctly claim the part, improvement,

or combination which [the inventor] claims as his

invention or discovery).”) (cleaned up).

This Court recognized that in “the area of patents,

it is especially important that the law remain stable

and clear.” Bilski v. Kappos, 561 U.S. 593, 613 (2010).

Thus, this Petition may be used to clarify the scope of

after-arising technology, by overruling the HoganEntresto line of cases, reaffirming that patent

specifications require a full written description of the

invention as claimed, and reaffirming that the scope

of the invention that forms the basis for infringement

must parallel the scope of the claims for invalidity

purposes.

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CONCLUSION

The Court should grant the petition for writ of

certiorari to clarify that after-arising technology

cannot be used for infringement purposes to ensnare

a competitor yet not be used for §112(a)’s compliance

with written description or enablement.

Respectfully submitted,

Shashank Upadhye

Counsel of Record

Upadhye Tang LLP

109 Symonds Dr. #174

Hinsdale, IL 60522

(312) 327-3326

shashank@ipfdalaw.com

Counsel for Amicus Curiae

October 8, 2025