USCA4 Appeal: 26-1473

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No. 26-1473

IN THE UNITED STATES COURT OF APPEALS

FOR THE FOURTH CIRCUIT

––––––––––––––––––––––––––––––––––––––––––––

CAREFIRST OF MARYLAND, INC.; GROUP HOSPITALIZATION

AND MEDICAL SERVICES, INC.; CAREFIRST BLUECHOICE, INC.,

on behalf of themselves and all others similarly situated,

Plaintiffs-Appellees,

AMGEN INC.; IMMUNEX CORPORATION;

AMGEN MANUFACTURING LIMITED LLC,

Defendants-Appellants.

–––––––––––––––––––––––––––––––––––––––––––––

On Appeal from the United States District Court for the

Eastern District of Virginia

No. 2:24-cv-00484 (Hon. Arenda L. Wright Allen)

–––––––––––––––––––––––––––––––––––––––––––––

BRIEF OF THE FEDERAL TRADE COMMISSION

AS AMICUS CURIAE IN SUPPORT OF NEITHER PARTY

–––––––––––––––––––––––––––––––––––––––––––––

LUCAS CROSLOW

General Counsel

H. THOMAS BYRON III

Deputy General Counsel

Of Counsel:

DANIEL W. BUTRYMOWICZ

ANUPAMA SAWKAR

Attorneys

FEDERAL TRADE COMMISSION

Washington, D.C. 20580

ROBERT A. SILVERSTEIN

Attorney

FEDERAL TRADE COMMISSION

600 Pennsylvania Ave. NW

Washington, D.C. 20580

(202) 325-2488

rsilverstein@ftc.gov

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TABLE OF CONTENTS

TABLE OF AUTHORITIES .................................................................................... ii

INTRODUCTION AND SUMMARY ......................................................................1

INTEREST OF AMICUS CURIAE ..........................................................................3

BACKGROUND .......................................................................................................4

ARGUMENT .............................................................................................................6

I. Acquisitions of Patent Applications Are Not Immune from Antitrust

Scrutiny. .................................................................................................................7

Pending Patent Applications, Like Issued Patents, Raise

Competitive Concerns. ..........................................................................8

Acquiring a patent application can constitute anticompetitive

conduct. .......................................................................................8

Amgen’s attempts to distinguish patent applications from

patents fall short..........................................................................13

Recognizing Liability Here Will Not Stifle Innovation. .....................16

II. Amgen’s Acquisition Is Not Protected under Noerr-Pennington. ................18

Noerr-Pennington Protects the Enforcement of Patents Through

Litigation, But Not the Underlying Acquisition of Patents or

Patent Applications. ............................................................................19

Noerr-Pennington does not protect commercial transactions

distinct from petitioning............................................................19

Breaking with the above precedent would cause serious and

far-reaching practical problems. ...............................................23

Amgen confuses antitrust violations with injury. .....................25

The Noerr-Pennington Doctrine Does Not Categorically

Immunize the Acquisition of Rights to a Patent Application. ............26

CONCLUSION ........................................................................................................30

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TABLE OF AUTHORITIES

CASES

A.D. Bedell Wholesale Co. v. Philip Morris Inc.,

263 F.3d 239 (3d Cir. 2001) ..............................................................................21

Allied Tube & Conduit Corp. v. Indian Head, Inc.,

486 U.S. 492 (1988) .................................................................................... 19, 24

Amphastar Pharms., Inc. v. Momenta Pharms., Inc.,

850 F.3d 52 (1st Cir. 2017) ......................................................................... 20, 21

Aronson v. Quick Point Pencil,

440 U.S. 257 (1979) ...........................................................................................17

Aspen Skiing Co. v. Aspen Highlands Skiing Corp.,

472 U.S. 585 (1985) .............................................................................................7

Atl. Richfield Co. v. USA Petroleum Co.,

495 U.S. 328 (1990) ...........................................................................................25

Baltimore Scrap Corp. v. David J. Joseph Co.,

237 F.3d 394 (4th Cir. 2001) ...................................................................... 27, 28

California v. Am. Stores Co.,

495 U.S. 271 (1990) ...........................................................................................26

Clipper Exxpress v. Rocky Mountain Motor Tariff Bureau, Inc.,

690 F.2d 1240 (9th Cir. 1982) ...........................................................................20

Coastal States Mktg., Inc. v. Hunt,

694 F.2d 1358 (5th Cir. 1983) ...........................................................................27

Columbia Steel Casting Co., Inc. v. Portland Gen. Elec. Co.,

111 F.3d 1427 (9th Cir. 1996) ...........................................................................21

Duke Energy Carolinas, LLC v. NTE Carolinas II, LLC,

111 F.4th 337 (4th Cir. 2024) ..............................................................................7

E. R.R. Presidents Conf. v. Noerr Motor Freight, Inc.,

365 U.S. 127 (1961) ...........................................................................................18

FTC v. AbbVie, Inc.,

976 F.3d 327 (3d Cir. 2020) ................................................................................3

FTC v. Actavis, Inc.,

570 U.S. 136 (2013)................................................................................ 3, 14, 25

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FTC v. Edwards Lifesciences Corp.,

No. 25-2569, 2026 WL 228723 (D.D.C. Jan. 28, 2026) ...................... 14, 15, 29

FTC v. Facebook, Inc.,

581 F. Supp. 3d 34 (D.D.C. 2022) .......................................................................5

FTC v. Superior Ct. Trial Laws. Ass’n,

493 U.S. 411 (1990) ...........................................................................................19

Fuel Automation Station, LLC v. Energera Inc.,

119 F.4th 1214 (10th Cir. 2024) ..........................................................................5

Grp. Life & Health Ins. Co. v. Royal Drug Co.,

440 U.S. 205 (1979) ...................................................................................... 2, 22

Handgards, Inc. v. Ethicon, Inc.,

601 F.2d 986 (9th Cir. 1979) .............................................................................24

Hartford-Empire Co. v. United States,

323 U.S. 386 (1945) .............................................................................................8

In re Cipro Cases I & II,

61 Cal. 4th 116 (2015) .......................................................................................14

In re Oetiker,

977 F.2d 1443 (Fed. Cir. 1992) .........................................................................16

Mayor of Baltimore v. AbbVie Inc.,

42 F.4th 709 (7th Cir. 2022) ..............................................................................23

McGuire Oil Co. v. Mapco, Inc.,

958 F.2d 1552 (11th Cir. 1992) .........................................................................22

Navient Sols., LLC v. Lohman,

136 F.4th 518 (4th Cir. 2025) ............................................................... 26, 27, 29

Octane Fitness, LLC v. ICON Health & Fitness, Inc.,

572 U.S. 545 (2014) ...........................................................................................18

Premier Elec. Const. Co. v. Nat’l Elec. Contractors Ass’n, Inc.,

814 F.2d 358 (7th Cir. 1987) .............................................................................22

PrimeTime 24 Joint Venture v. Nat’l Broad. Co., Inc.,

219 F.3d 92 (2d Cir. 2000) ................................................................................20

SCM Corp. v. Xerox Corp.,

645 F.2d 1195 (2d Cir. 1981) ..............................................................................7

Sosa v. DIRECTV, Inc.,

437 F.3d 923 (9th Cir. 2006) .............................................................................27

iii

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United Mine Workers v. Pennington,

381 U.S. 657 (1965) .................................................................................... 19, 20

United States v. Microsoft Corp.,

253 F.3d 34 (D.C. Cir. 2001) .............................................................................14

United States v. Singer Mfg. Co.,

374 U.S. 174 (1963) .............................................................................................8

Waugh Chapel S., LLC v. United Food & Com. Workers Union Loc. 27,

728 F.3d 354 (4th Cir. 2013) .............................................................................18

STATUTES

15 U.S.C. § 1 ..............................................................................................................9

15 U.S.C. § 2 ..............................................................................................................9

15 U.S.C. § 15 ............................................................................................................9

15 U.S.C. § 18a ..........................................................................................................5

15 U.S.C. §§ 41 et seq................................................................................................3

35 U.S.C. § 102 ........................................................................................................16

35 U.S.C. § 120 ........................................................................................................11

35 U.S.C. § 131 ........................................................................................................16

35 U.S.C. § 151 ........................................................................................................16

OTHER AUTHORITIES

Amphastar Pharms., Inc. v. Momenta Pharms., Inc.,

No. 16-2113, Doc. 00117081683 (1st Cir. Nov. 7, 2016) ...................................3

Commission Opinion,

In re Illumina, Inc., FTC Dkt. No. 9401, (Apr. 3, 2023) ...................................15

Decision & Order,

In re AbbVie Inc, FTC Dkt. No. C-4713 (Sept. 4, 2020)...................................15

Decision & Order,

In re Elanco Animal Health Inc., FTC Dkt. No. C-4725

(Sept. 11, 2020) ..................................................................................................15

Donald S. Chisum, Chisum on Patents § 13.01 (vol. 4A 2026) ..............................11

Erik Hovenkamp & Herbert Hovenkamp, Buying Monopoly:

Antitrust Limits on Damages for Externally Acquired

Patents, 25 Tex. Intell. Prop. L.J. 39 (2017) .............................................. 17, 18

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FTC Office of Policy Planning, Enforcement Perspectives on

the Noerr-Pennington Doctrine: An FTC Staff Report

(2006) ...................................................................................................................3

FTC Office of Policy Planning, Report of the State Action Task

Force (Sept. 2003) ...............................................................................................3

FTC, The Evolving IP Marketplace: Aligning Patent Notice and

Remedies with Competition (Mar. 2011) .................................................... 10, 13

FTC, To Promote Innovation: The Proper Balance of

Competition and Patent Law and Policy (Oct. 2003) .......................................12

Initial Decision,

In re Illumina, Inc., FTC Dkt. No. 9401 (Sept. 9, 2022) ...................................15

Intell. Ventures I LLC v. Cap. One Fin. Corp.,

No. 18-1367 (Fed. Cir. May 11, 2018), Dkt. 41 ..................................................3

Mark A. Lemley & Kimberly A. Moore, Ending Abuse of

Patent Continuations,

84 B.U. L. Rev. 63 (2004) .................................................................... 10, 12, 13

Mark A. Lemley and Carl Shapiro, Probabilistic Patents,

19 J. of Econ. Persps. 75 (2005) ........................................................................14

Phillip E. Areeda & Herbert Hovenkamp, Antitrust Law (2025) ..............................8

Tun-Jen Chiang, Fixing Patent Boundaries,

108 Mich. L. Rev. 523 (2010) .................................................................... 10, 13

U.S. DOJ & FTC, Antitrust Guidelines for the Licensing of

Intellectual Property (Jan. 12, 2017) ............................................................ 3, 16

REGULATIONS

16 C.F.R. § 801.2 .......................................................................................................6

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INTRODUCTION AND SUMMARY

Most acquisitions and licensing arrangements for patent rights or patent

applications simply transfer rights from one party to another without changing

overall competitive conditions. But courts have long recognized that acquiring a

patent can violate the antitrust laws if it increases the purchaser’s market power.

This concern is particularly acute when an acquisition or license transfers rights

between actual or potential competitors with intellectual property (“IP”) covering

the same product. The Federal Trade Commission (“FTC”) and Department of

Justice (“DOJ”) routinely review acquisitions of, or exclusive licenses to, patents

and patent applications to screen for such anticompetitive effects.

This interlocutory appeal threatens to upend that long-settled framework.

Defendants Amgen, Inc., Immunex Corporation, and Amgen Manufacturing

Limited LLC (collectively, “Amgen”) acquired exclusive rights to patents and

patent applications from a potential competitor, extending Amgen’s monopoly on

the drug Enbrel (etanercept) by fifteen years. The district court correctly rejected

Amgen’s arguments that (1) acquisitions of patent applications—as opposed to

issued patents—should be per se legal under the antitrust laws, and (2) this private

commercial transaction should be shielded under the Noerr-Pennington doctrine

because Amgen subsequently prosecuted the patent applications and sued in court

to enjoin competitors from the market.

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“It is well settled that exemptions from the antitrust laws are to be narrowly

construed.” Grp. Life & Health Ins. Co. v. Royal Drug Co., 440 U.S. 205, 231

(1979). Amgen’s novel and sweeping arguments find no support in case law and, if

accepted, would pose a substantial threat to competition.

First, acquisitions of patent applications are not categorically immune from

antitrust scrutiny. The acquisition of IP rights indisputably can constitute

anticompetitive conduct. And there is no meaningful antitrust distinction between

the acquisition of a patent and the acquisition of a patent application: both can

allow monopolists to maintain their monopoly power through some basis other

than competition on the merits. In fact, some aspects of patent applications create

anticompetitive concerns that issued patents do not; they give a monopolist more

flexibility to seek to tailor the exclusionary scope of the patent to increase its

monopoly.

Second, the acquisition of a patent application is not protected under NoerrPennington. Amgen’s acquisition was a private commercial transaction, and any

subsequent petitioning of the U.S. Patent and Trademark Office (“USPTO”) or the

district court was a separate step that merely maximized the value of the assets it

acquired. While Noerr-Pennington may protect Amgen’s petitioning activity, that

protection does not attach to prior conduct that maintains monopoly power through

anticompetitive means.

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INTEREST OF AMICUS CURIAE

The FTC promotes competition and protects consumer welfare through

enforcement of the federal antitrust laws. See 15 U.S.C. §§ 41 et seq. In that

capacity, it has issued staff reports addressing the appropriate scope and likely

impact of antitrust exemptions such as Noerr-Pennington,1 and has filed amicus

curiae briefs in similar cases.2

The FTC also reviews patent acquisitions and exclusive patent licenses

under the Hart-Scott-Rodino (HSR) Act, which requires companies to provide

advance notice of large mergers and acquisitions. The FTC has issued guidance

and brought cases related to the intersection of patents and the enforcement of

antitrust laws.3

See, e.g., FTC Office of Policy Planning, Enforcement Perspectives on the NoerrPennington Doctrine: An FTC Staff Report (2006), https://tinyurl.com/43erfw7p;

FTC Office of Policy Planning, Report of the State Action Task Force (Sept. 2003),

https://tinyurl.com/ysvjmxrt.

See, e.g., Intell. Ventures I LLC v. Cap. One Fin. Corp., No. 18-1367 (Fed. Cir.

May 11, 2018), Dkt. 41; Amphastar Pharms., Inc. v. Momenta Pharms., Inc., No.

16-2113, Doc. 00117081683 (1st Cir. Nov. 7, 2016).

See, e.g., U.S. DOJ & FTC, Antitrust Guidelines for the Licensing of Intellectual

Property (Jan. 12, 2017), https://www.justice.gov/atr/IPguidelines/dl; FTC v.

Actavis, Inc., 570 U.S. 136 (2013); FTC v. AbbVie, Inc., 976 F.3d 327 (3d Cir.

2020).

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BACKGROUND

This case concerns Amgen’s patent rights for its biologic drug Enbrel.

Immunex Corporation (“Immunex”) obtained a series of patents covering Enbrel’s

active ingredient, etanercept. JA0241–0242. In 1998, Immunex launched Enbrel in

the United States to treat inflammatory diseases like rheumatoid arthritis. JA0242.

F. Hoffman-La Roche (“Roche”), however, had already described etanercept

in its own patent applications, which predated Immunex’s applications; as a result,

Roche had a priority right to the technology Immunex used to create the drug.

JA0237–0240, JA0243. Immunex obtained a non-exclusive license to the relevant

patents from Roche. JA0238–0239, JA0243. Roche retained the ability to

commercialize its own version of the drug or license the patents to another

company seeking to develop a competing version. JA0223–0224.

Enbrel proved to be a blockbuster drug. JA0244-0245. In large part due to

Enbrel’s commercial success, Amgen acquired Immunex. JA0246–0247. Amgen

promptly took over marketing Enbrel, with the key patents for the drug set to

expire in 2012. JA0250–0251.

Seeking to extend its exclusivity beyond 2012, Amgen restructured

Immunex’s 1998 license agreement with Roche.4 JA0251. Under the 2004

The restructuring deal was submitted to the FTC, which granted early termination

of the HSR waiting period. Early termination merely reflects that “neither [the FTC

(Continued…)

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restructured agreement, Amgen obtained exclusive rights to the etanercept patent

family—including control over the prosecution of two pending Roche patent

applications—as well as the ability to sue companies seeking to market etanercept

biosimilars.5 JA0252–0253.

Those two pending patent applications proved critical to Amgen extending

its monopoly over Enbrel. The USPTO issued the patents in 2011 and 2012, giving

Amgen exclusive rights to patents covering Enbrel through 2029. JA0257–0258.

Amgen then used those issued patents to block its competitors from marketing

Enbrel biosimilars, obtaining permanent injunctions against two firms (Sandoz and

Bioepsis). JA0259, JA0261, JA0211–0214, JA0216–0217. The injunctions

terminate upon the expiration of both patents, on April 24, 2029—seventeen years

after Amgen’s initial Enbrel patents expired in 2012. JA0250, JA0261.

CareFirst filed a class action alleging that the acquisition of these patent

applications constituted anticompetitive conduct that maintained Amgen’s

monopoly in violation of Section 2 of the Sherman Act. JA0279–0282. In moving

nor DOJ] intends to take any action” during the waiting period. 15 U.S.C.

§ 18a(b)(2). It is not a determination of legality, does not constitute an

endorsement of the transaction, and does not preclude later antitrust scrutiny. See

FTC v. Facebook, Inc., 581 F. Supp. 3d 34, 57 (D.D.C. 2022).

A patent family is a group of related patents and applications that claim priority

to the same application and generally share the same specification. See Fuel

Automation Station, LLC v. Energera Inc., 119 F.4th 1214, 1228 (10th Cir. 2024).

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to dismiss, Amgen argued that its private transaction obtaining exclusive rights to

Roche’s patent applications was immune from antitrust scrutiny under NoerrPennington because it later obtained injunctions enforcing the issued patents.

JA0451–0455. The district court disagreed, concluding that although the later

litigation was protected by Noerr-Pennington, the overall scheme—beginning with

the acquisition of Roche’s patent rights—remained actionable. JA0039. The

district court further rejected Amgen’s separate contention that the acquisition of

pending patent applications cannot constitute anticompetitive conduct as a matter

of law. JA0030–0035. It then certified both questions for interlocutory appeal

under 28 U.S.C. § 1292(b). JA0522.

ARGUMENT

Amgen seeks a sweeping rule that would prevent antitrust scrutiny of private

commercial agreements acquiring the rights to patent applications.6 First, Amgen

argues categorically that the acquisition of patent applications cannot violate the

antitrust laws. Second, Amgen argues that the acquisition of a patent application is

For simplicity, this brief refers to the 2004 exclusive license as an acquisition,

reflecting Amgen’s exclusive control over prosecution of the applications and its

ability to enforce the resulting patents. Amgen does not argue for purposes of this

case that its exclusive licensing agreement should be treated any differently than an

acquisition of a patent application. See also 16 C.F.R. § 801.2(g) (explaining that

an exclusive patent license is substantively the same as a purchase).

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immune from liability under Noerr-Pennington. Neither argument accords with

legal precedent or economic reality.

ACQUISITIONS OF PATENT APPLICATIONS ARE NOT IMMUNE FROM

ANTITRUST SCRUTINY.

A monopolization claim requires allegations that the defendant willfully

acquired or maintained monopoly power “through anticompetitive conduct, as

opposed to gaining its monopoly status ‘as a consequence of a superior product,

business acumen, or historic accident.’” Duke Energy Carolinas, LLC v. NTE

Carolinas II, LLC, 111 F.4th 337, 353 (4th Cir. 2024) (quoting United States v.

Grinnell Corp., 384 U.S. 563, 571 (1966)).7 It is well settled that acquiring patent

rights can constitute anticompetitive conduct. As Amgen itself acknowledges,

“Patent acquisitions are not immune from the antitrust laws.” SCM Corp. v. Xerox

Corp., 645 F.2d 1195, 1205 (2d Cir. 1981); see Amgen Br. 42. Where a monopolist

acquires “exclusive rights in related patents,” that acquisition “should

presumptively be a § 2 ‘exclusionary practice’ … if the effect of the acquisition is

to give the acquirer an exclusive right in them and this serves to increase or

prolong the monopolist’s market power.” Phillip E. Areeda & Herbert Hovenkamp,

The term “anticompetitive conduct” in monopolization cases is often used

synonymously with another term of art—“exclusionary conduct”—which the

Supreme Court has defined as behavior that “(1) tends to impair the opportunities

of rivals” and “(2) either does not further competition on the merits or does so in

an unnecessarily restrictive way.” Aspen Skiing Co. v. Aspen Highlands Skiing

Corp., 472 U.S. 585, 605 n.32 (1985) (cleaned up).

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Antitrust Law ¶ 707 (2025). This principle is equally true where the acquisition of a

patent application is concerned, for the reasons discussed below.

Pending Patent Applications, Like Issued Patents, Raise

Competitive Concerns.

1. Acquiring a patent application can constitute anticompetitive conduct.

Whether a monopolist acquires either a patent application or an issued

patent, that transaction can amount to anticompetitive conduct that violates the

antitrust laws.

Nothing about the antitrust laws or the nature of patent applications warrants

different treatment for applications. The Supreme Court indicated as much in

United States v. Singer Mfg. Co., 374 U.S. 174, 189 (1963). Singer engaged in a

series of transactions—including acquiring both issued patents and pending patent

applications—to exclude competition in the sewing machine market. In recounting

Singer’s course of conduct, the Court noted evidence that Singer believed it could

“rewrite the claims” of the pending application “before the patent … issued” to

“make it stronger than it now is.” Id. at 182. The Court found an illegal Section 1

conspiracy, concluding that the Sherman Act “imposes strict limitations on the

concerted activities in which patent owners may lawfully engage.” Id. at 197.

Nowhere in its analysis did the Court distinguish pending applications from issued

patents. See also Hartford-Empire Co. v. United States, 323 U.S. 386, 395 (1945)

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(defendants used “purchases of [patent] applications and patents” in violation of

the Sherman Act).

Nor should it have. To hold otherwise would make a mockery of Section 2.

Indeed, under Amgen’s framing, a monopolist would enjoy total immunity if it

bought its rivals’ assets and squelched competition a single day before patent

issuance. But the very next day, that same conduct—with materially

indistinguishable competitive consequences—would be subject to treble damages

and, potentially, criminal sanctions. 15 U.S.C. §§ 1, 2, 15.

To be sure, a patent application is different from an issued patent. It carries

some uncertainty about the scope of any eventual patent, as well as the risk that no

patent issues. But a patent application can also confer unique strategic advantages

that can, in some circumstances, lead to more anticompetitive harm than acquiring

an issued patent. Control of a patent application allows the holder to leverage:

(1) prosecution control, (2) priority date, (3) continuation practice, and

(4) competitive uncertainty for rivals. These advantages allow a monopolist who

purchases a patent application broad opportunities to increase its monopoly.8

Many competitive strengths of patent applications relate to their prosecution. As

explained in Part II, though this subsequent prosecution is itself protected by

Noerr-Pennington, that immunity does not extend to an anticompetitive

acquisition. The petitioning only occurs after the commercial transaction has taken

place, and serves as one means of maximizing the transaction’s value.

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a) Prosecution Control

A patent applicant has the unique ability to manipulate, expand, or pivot its

patent claims over time, long after the application is first filed. In controlling an

application’s prosecution, the applicant can effectively paralyze the competitive

landscape.

When a patent application is filed, it includes a “specification” that can stake

out broad conceptual territory—often far broader than any single invention. The

specification concludes with a set of “claims” that describes the particular scope of

the exclusivity sought. See Tun-Jen Chiang, Fixing Patent Boundaries, 108 Mich.

L. Rev. 523, 527 (2010). The applicant is free to later “amend or insert claims

intended to cover a competitor’s product the applicant’s attorney has learned about

during the prosecution of a patent application.”9 The party controlling prosecution

can tweak the application’s claims, cancel existing claims, or even add entirely

new claims to the application. Mark A. Lemley & Kimberly A. Moore, Ending

Abuse of Patent Continuations, 84 B.U. L. Rev. 63, 64 (2004). That ability to take

affirmative steps to adjust the scope of the patent application’s claims is a strategic

advantage that can allow a monopolist to seek to tailor the patent to exclude

competitors’ later scientific developments and extend its monopoly.

FTC, The Evolving IP Marketplace: Aligning Patent Notice and Remedies with

Competition (Mar. 2011) at 87 & n.92 (citation omitted),

https://tinyurl.com/3z75u72y.

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This case illustrates the significance of prosecution control. Immunex

initially took a non-exclusive license to Roche’s IP—even though Roche did not

yet have patents covering Enbrel—because Roche’s original patent application

specification described etanercept, leaving open the possibility that future claims

might cover Enbrel. Amgen Br. 4–5; JA0006–0007. Then Amgen, despite already

having a non-exclusive license that ensured it could sell Enbrel without infringing

Roche’s IP rights, paid Roche to restructure the deal so that it acquired exclusive

control over two pending applications. Amgen used that exclusive control to

change the claims in Roche’s patent applications, ensuring the USPTO would issue

patents tailored to Enbrel. JA0257–0258. Those patents ultimately secured Amgen

years of further market exclusivity.

b) Priority Date

The date a patent application is filed becomes the “priority” date that gives it

precedence over subsequent filings. Prior art (e.g., scientific publications,

competing patents) can only defeat a claim’s patentability if it predates that priority

date. Critically, subsequent applications in the same patent family inherit the

priority date of the initial application. See 35 U.S.C. § 120; see also Donald S.

Chisum, Chisum on Patents § 13.01 (vol. 4A 2026). The priority date of the

original application anchors every patent claim pursued in that application or in

any related continuation application—regardless of how many years later a

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continuation application is filed or how different the eventual claims look from

what was originally sought. Thus, when Amgen acquired control over Roche’s

applications in 2004, it inherited the applications’ earlier priority date. JA0251.

That priority date meant Amgen could pursue patent claims based on Roche’s

specification, shielded from the intervening fifteen years of scientific development

that might otherwise have constituted prior art.

c) Continuation Practice

Control of a pending application also provides the ability to file continuation

applications—new patent applications that claim the benefit of an earlier “parent”

application’s priority date and disclosure, and must be filed while the parent

application remains pending. Lemley & Moore at 66. Because a continuation

application is treated as a new application, prosecution begins again—giving the

applicant another opportunity to shape its claims in response to developments in

the marketplace since the parent was filed.

The FTC has recognized that applicants may keep applications pending,

monitor market developments, and modify their claims to capture additional

subject matter, including competitors’ products. FTC, To Promote Innovation: The

Proper Balance of Competition and Patent Law and Policy, Ch. 4(II)(C)(1) (Oct.

2003). That conduct, in turn, allows an applicant to expand a patent family over

time, adopt new claiming strategies as markets evolve, and potentially build a

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dense set of related patents that deters or delays rivals. See Lemley & Moore at 71–

83 (describing the “pernicious consequences” of continuation applications). By

comparison, an issued patent offers something far less dynamic: a fixed set of

rights based on the claims already allowed.

d) Competitive Uncertainty

The foregoing aspects of patent applications can create anticompetitive

effects through the uncertainty they generate. Because the scope of a pending

application’s claims remains unsettled—and may expand or shift through

continuation filings—competitors cannot reliably design around claims that are

still evolving. This strategic uncertainty can delay or deter investment, product

development, and market entry even before any patent issues. See The Evolving IP

Marketplace at 87–89; Chiang at 525–26, 533–34, 536–37.

Taken together, these competitive advantages reinforce one another.

Prosecution control shapes the application’s claims; priority date anchors those

claims to an earlier moment in time; continuation practice allows new claims to be

pursued indefinitely from that anchoring date; and the resulting uncertainty can

effectively constrain rivals even before any patent issues.

2. Amgen’s attempts to distinguish patent applications from patents fall

short.

First, Amgen contends (Br. 41) that patent applications are not exclusionary

because of their probabilistic nature, emphasizing that a patent application may not

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ultimately issue. But even issued patents carry with them uncertainty. See Actavis,

570 U.S. at 147 (“[T]o refer … simply to what the holder of a valid patent could do

does not by itself answer the antitrust question. The patent here may or may not be

valid, and may or may not be infringed.”). Indeed, patents themselves “are in a

sense probabilistic, rather than ironclad: they grant their holders a potential but not

certain right to exclude.” In re Cipro Cases I & II (2015) 61 Cal. 4th 116, 143.

Patents are therefore best understood as conferring not the right to exclude “but

rather a right to try to exclude.” Mark A. Lemley and Carl Shapiro, Probabilistic

Patents, 19 J. of Econ. Persps. 75, 76 (2005) (explaining that the “risk that a patent

will be declared invalid is substantial,” as “[r]oughly half of all litigated patents are

found to be invalid”).

This type of uncertainty is also commonplace in antitrust enforcement,

which routinely addresses—and condemns—conduct on the basis of potential or

probabilistic future harms. In United States v. Microsoft Corp., 253 F.3d 34, 79

(D.C. Cir. 2001), the D.C. Circuit explained that uncertain conduct could violate

Section 2 where it appeared “reasonably capable of contributing significantly to a

defendant’s continued monopoly power.” And earlier this year in FTC v. Edwards

Lifesciences Corp., No. 25-2569, 2026 WL 228723 (D.D.C. Jan. 28, 2026), a court

enjoined the merger of two companies that owned pre-commercialization medical

devices. Even though FDA approval of the pending applications for each medical

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device—like USPTO approval of a pending patent application—was “not a

certainty,” id. at *32, the merger of ownership for two pre-approval devices was

“likely to lessen competition substantially,” id. at *29.

The FTC undertakes that same analysis in reviewing a firm’s IP in the

context of a merger. In In re Illumina, Inc., FTC Dkt. No. 9401, the FTC found that

Illumina’s acquisition of GRAIL was anticompetitive in part because Illumina’s

hundreds of issued patents and pending applications discouraged developers from

adopting competing sequencing platforms, and at least one emerging competitor

identified IP risk as a barrier to commercialization.10 Likewise, the FTC’s consent

orders routinely define “patent(s)” to include pending applications because those

applications can support future patent claims capable of undermining divested

assets or recreating the harms the order is designed to prevent.11

Second, Amgen argues that patent applications should be treated differently

from the patents that eventually issue because applications are “nothing more than

requests for exclusionary rights.” Amgen Br. 39. But a patent application is not a

See Initial Decision (Sept. 9, 2022), https://tinyurl.com/3wuakewe (Finding of

Fact ¶¶ 9, 599); see also Commission Opinion (Apr. 3, 2023) at 7–9 (citing IDF

¶¶ 664, 666, 697–98), https://tinyurl.com/3z88vn9f.

See, e.g., Decision & Order, In re Elanco Animal Health Inc., FTC Dkt. No. C4725 (Sept. 11, 2020) at § NN, https://tinyurl.com/35a7a8ys; Decision & Order, In

re AbbVie Inc., FTC Dkt. No. C-4713 (Sept. 4, 2020) at § NN,

https://tinyurl.com/ykbctzce.

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hollow supplication—it is an inchoate property right, as the Patent Act evinces.

Congress has made clear that an applicant is entitled to a patent unless the USPTO

can prove unpatentability. See 35 U.S.C. §§ 102 (“entitled to a patent unless”), 131

(USPTO “shall issue” a patent if the applicant is entitled), 151 (same); see also In

re Oetiker, 977 F.2d 1443, 1445 (Fed. Cir. 1992) (the patent examiner—not the

applicant—bears the initial burden of dislodging applicant’s entitlement to a

patent). A patent application and an issued patent are thus best understood as

points on a single statutory continuum: one at an earlier stage on that continuum,

conferring a legally protected expectation of issuance, and one fully matured.

Recognizing Liability Here Will Not Stifle Innovation.

Amgen warns (Br. 54–56) that innovation will suffer if the Court recognizes

that pending applications can pose anticompetitive concerns. That alarmism is

unfounded.

The FTC recognizes that IP licensing can often be procompetitive. See U.S.

DOJ & FTC, Antitrust Guidelines §§ 2.0, 2.3, 3.1. Most licenses are non-exclusive

and, barring unusual circumstances, are unlikely to present antitrust concerns. Id. at

§ 4.1.2. Exclusive licenses, however, warrant antitrust scrutiny where they threaten

to reduce competition—usually because the parties are competitors or potential

competitors. Id. Subjecting this narrow category of deals to antitrust scrutiny adds

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no new compliance burden, since transactions that meet HSR reporting thresholds

are already reviewed by the FTC and DOJ.

Amgen also mischaracterizes its cited authority by equating an innovator’s

licensing of an application to a non-competitor (which generally promotes

commercialization and competition) with a competitor’s exclusive licensing to a

monopolist (which stifles both). See Amgen Br. 55–56. Aronson v. Quick Point

Pencil, 440 U.S. 257, 261–62 (1979), for example, is inapposite because the

Supreme Court there endorsed an inventor licensing her own application to a noncompetitor to enable commercialization of her invention (a procompetitive

outcome). See Amgen Br. 55. Amgen’s reliance on the Hovenkamp Buying

Monopoly article undermines its own argument. Id. That article explains that while

most patent assignments are procompetitive because they facilitate

commercialization, acquisitions by a dominant firm of “substitute patents from

external patentees” can “impede product market rivals by limiting their access to

important technological inputs.” Erik Hovenkamp & Herbert Hovenkamp, Buying

Monopoly: Antitrust Limits on Damages for Externally Acquired Patents, 25 Tex.

Intell. Prop. L.J. 39, 39 (2017). The authors stress that the Patent Act never

justifies “the acquisition of individual patent rights into portfolios that dominate a

market, something that … the antitrust laws rightfully prohibit.” Id. They therefore

propose that where a dominant firm acquires patents in its own technology market,

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“its acquisition be limited to a nonexclusive license,” because limiting dominant

firms to nonexclusive rights “will tend to increase innovation by discouraging

systematic monopoly in technology markets.” Id. at 40 (emphasis added). In short,

that article warns against precisely what occurred here: exclusive acquisitions by

monopolists.

II.

AMGEN’S ACQUISITION IS NOT PROTECTED UNDER NOERR-PENNINGTON.

The district court properly concluded that Amgen’s acquisition of patent

applications is not protected from the antitrust laws merely because Amgen later

prosecuted those applications and enforced the issued patents through litigation.

Under Noerr-Pennington, “defendants are immune from antitrust liability for

engaging in conduct (including litigation) aimed at influencing decisionmaking by

the government.” Octane Fitness, LLC v. ICON Health & Fitness, Inc., 572 U.S.

545, 556 (2014) (citing E. R.R. Presidents Conf. v. Noerr Motor Freight, Inc., 365

U.S. 127 (1961); United Mine Workers v. Pennington, 381 U.S. 657 (1965)).

Noerr-Pennington “safeguards the First Amendment right to ‘petition the

government for a redress of grievances,’ by immunizing citizens from the liability

that may attend the exercise of that right.” Waugh Chapel S., LLC v. United Food

& Com. Workers Union Loc. 27, 728 F.3d 354, 362 (4th Cir. 2013) (internal

citation omitted). Thus, legitimate petitioning activity, even when “intended to

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eliminate competition,” “is not illegal, either standing alone or as part of a broader

scheme itself violative of the [antitrust laws].” Pennington, 381 U.S. at 670.

Noerr-Pennington immunity is not boundless, however. The doctrine

extends only to petitioning activity and restraints that are “‘incidental’ to a valid

effort to influence governmental action.” Allied Tube & Conduit Corp. v. Indian

Head, Inc., 486 U.S. 492, 499 (1988) (quoting Noerr, 365 U.S. at 143). The

Supreme Court has repeatedly cautioned against an “absolutist” approach,

underscoring that Noerr-Pennington “does not extend to ‘every concerted effort

that is genuinely intended to influence governmental action.’” FTC v. Superior Ct.

Trial Laws. Ass’n, 493 U.S. 411, 425 (1990) (quoting Allied Tube, 486 U.S. at

503). Amgen’s arguments represent precisely the kind of Noerr-Pennington

absolutism the Supreme Court has rejected.

Noerr-Pennington Protects the Enforcement of Patents Through

Litigation, But Not the Underlying Acquisition of Patents or

Patent Applications.

1. Noerr-Pennington does not protect commercial transactions distinct

from petitioning.

This Court should make clear that Noerr-Pennington does not preclude

antitrust liability for acquiring patent rights where a monopolist later sues to

enforce those rights in court. A wealth of case law supports this proposition. To

start, the Supreme Court suggested as much in Pennington itself. 381 U.S. at 670.

The Court stated that petitioning activity was not illegal, “either standing alone or

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as part of a broader scheme itself violative of the Sherman Act.” Id. (emphasis

added). Thus, Noerr-Pennington protects petitioning, but non-petitioning aspects

of the same anticompetitive scheme may remain “violative of the Sherman Act.”

See also Clipper Exxpress v. Rocky Mountain Motor Tariff Bureau, Inc., 690 F.2d

1240, 1265 (9th Cir. 1982) (explaining Pennington provides immunity only for

“the narrow petitioning activity”).

The Second Circuit addressed this issue directly in PrimeTime 24 Joint

Venture v. National Broadcasting. Co., 219 F.3d 92 (2d Cir. 2000). There, a

satellite operator alleged that network broadcasters engaged in a concerted refusal

to negotiate copyright licenses in violation of the Sherman Act. Id. at 97. The

broadcasters argued that this alleged agreement was protected from antitrust

scrutiny because they subsequently filed copyright-infringement lawsuits. Id. at

102. The Second Circuit rejected that argument, explaining that “copyright holders

may not agree to limit their individual freedom of action in licensing future rights

to such an infringer before, during, or after the lawsuit.” Id. at 103. “Such an

agreement would, absent litigation, violate the Sherman Act, and cannot be

immunized by the existence of a common lawsuit.” Id. (internal citation omitted).

Likewise, in Amphastar Pharmaceuticals, Inc. v. Momenta

Pharmaceuticals, Inc., 850 F.3d 52, 57 (1st Cir. 2017), the First Circuit held that

“[t]he mere existence of a lawsuit does not retroactively immunize prior anti-

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competitive conduct.” The plaintiff there alleged that defendants did not disclose to

a standard-setting organization that a pending patent application covered their

proposed method for testing a generic drug. Id. at 54. The defendants subsequently

obtained a preliminary injunction against the plaintiff for patent infringement. Id.

The First Circuit reversed the district court’s dismissal of the plaintiff’s Sherman

Act claims, which had reasoned that the defendants’ conduct was immunized under

Noerr-Pennington. Id. at 56. That “the alleged damages are based, in part, on a

lawsuit seeking an injunction does not ‘defeat the antitrust claim based on conduct

before the standard-setting organization.’” Id. at 57 (citation omitted). Amgen tries

to carve out “an exception” for Amphastar by noting the alleged underlying

antitrust violation was rooted in fraud. See Amgen Br. 26 n.11. But that fact had no

bearing on the court’s analysis and offers no basis to distinguish Amphastar.

Other circuits have held similarly. See A.D. Bedell Wholesale Co. v. Philip

Morris Inc., 263 F.3d 239, 251 (3d Cir. 2001) (“Private parties cannot immunize

an anticompetitive agreement merely by subsequently requesting legislative

approval.”); Columbia Steel Casting Co., Inc. v. Portland Gen. Elec. Co., 111 F.3d

1427, 1446 (9th Cir. 1996) (finding Noerr-Pennington inapplicable where utility

companies obtained order from state agency adopting anticompetitive contract, as

the defendant “is not being held liable for filing the application” but instead “is

being held liable for agreeing … to replace competition with area monopolies”);

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Premier Elec. Const. Co. v. Nat’l Elec. Contractors Ass’n, Inc., 814 F.2d 358, 376

(7th Cir. 1987) (holding Noerr-Pennington did not immunize underlying pricefixing contract that defendants sought to enforce in court).

These cases confirm that, while the act of bringing an infringement lawsuit

is itself protected by Noerr-Pennington, the lawsuit does not shield prior

anticompetitive conduct from antitrust liability. Stretching the boundaries of

Noerr-Pennington to immunize the entire course of conduct would run counter to

the Court’s directive that antitrust exemptions be narrowly construed. See Grp. Life

& Health Ins. Co., 440 U.S. at 231.

Thus, if Amgen maintained its monopoly through an unlawful acquisition of

patent rights (including the rights to pending patent applications), it violated the

antitrust laws—regardless of whether it later filed infringement claims to enforce

its patent rights. See JA0130 (alleging the acquisition violated the antitrust laws).12

Indeed, Amgen would have committed the same alleged violation even if it had

acquired the rights and “left them in a drawer” (Amgen Br. 50); the unlawfulness

of Amgen’s acquisition does not hinge on the subsequent infringement litigation.

Cf. McGuire Oil Co. v. Mapco, Inc., 958 F.2d 1552, 1561 (11th Cir. 1992) (Noerr-

Because CareFirst has challenged the alleged antitrust violation, not the validity

of the patents litigated in the Federal Circuit, Amgen’s concerns that CareFirst’s

claims amount to a “collateral attack” (Br. 27–28) are unfounded.

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Pennington immunity applied where defendants did not “allege any facts

independent of plaintiffs’ pre-litigative [threat of litigation] and litigative activities

to establish that a conspiracy in violation of the Sherman Act took place”).

For that reason, Amgen’s primary authority, Mayor of Baltimore v. AbbVie

Inc., 42 F.4th 709, 711 (7th Cir. 2022), is not “highly analogous to this case.”

Amgen Br. 48–49. The Seventh Circuit did not address acquisitions at all. The

defendant there “obtained” patents through its “successful petition[ing]”—

prosecuting its patent applications before the USPTO—and later “invok[ed]” the

issued patents in litigation. Mayor, 42 F.4th at 711–13. The court observed that the

claim in that case was based on a “concern about the successful outcome of [a

defendant’s] petitioning” the USPTO; the dicta about “costs on rivals” “imposed

by the process of petitioning” is thus irrelevant to this case. Id. at 714. The Seventh

Circuit recognized that Noerr-Pennington protected the act of filing and

prosecuting patent applications; it said nothing about an underlying commercial

transaction to acquire exclusive rights to patent applications.

2. Breaking with the above precedent would cause serious and farreaching practical problems.

To extend Noerr-Pennington here would suppress competition without

serving any of the doctrine’s purposes. And the risks of that extension are both

clear and far-reaching.

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Under Amgen’s view, any anticompetitive scheme could be insulated from

antitrust enforcement so long as the monopolist later engaged in some form of

petitioning. The acquisition of an issued patent—which Amgen concedes is

generally subject to antitrust review (Br. 42)—would be shielded if it was later

enforced via petitioning the courts. Such an outcome is contrary to established

precedent. See Handgards, Inc. v. Ethicon, Inc., 601 F.2d 986, 994 (9th Cir. 1979).

Similarly, if a participant in a price-fixing conspiracy sues a defector for breach of

contract, the underlying conspiracy remains illegal. See Allied Tube, 486 U.S. at

503 (not all conduct aimed to influence government action is protected, as

otherwise “competitors would be free to enter into horizontal price agreements as

long as they wished to propose that price as an appropriate level for governmental

ratemaking or price supports”).

Indeed, Amgen’s approach would create an arbitrary regime in which the

antitrust legality of an agreement depended on whether it later led to a lawsuit. A

patent or patent application acquisition would be protected if the acquirer sued

someone for infringement, but unprotected if competitors opted to avoid the

market entirely. A price-fixing agreement would be protected if the participants

petitioned the government to endorse the price, but not otherwise. Worse, NoerrPennington protection would change over time: an acquisition of patents or patent

applications that violated the antitrust laws would be illegal until the acquirer

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brought an enforcement suit, at which point it would retroactively be protected.

The scope of antitrust liability should not be so easily manipulated.

3. Amgen confuses antitrust violations with injury.

Amgen’s argument also muddles an important distinction between two

disparate legal concepts: antitrust violations and private plaintiff antitrust injury.

Amgen’s brief nominally frames its Noerr-Pennington causation arguments in

terms of private plaintiff antitrust injury, rather than substantive antitrust liability.

But in substance, Amgen contends Noerr-Pennington immunizes them from

liability. See Amgen Br. 29–30 (arguing “causation of injury from anticompetitive

conduct is an element of antitrust liability”). That is wrong.

As the Supreme Court has explained, “[P]roof of a[n antitrust] violation and

of antitrust injury are distinct matters that must be shown independently.” Atl.

Richfield Co. v. USA Petroleum Co., 495 U.S. 328, 344 (1990) (citation omitted).

All antitrust plaintiffs, private and public, must establish that the antitrust laws

have been violated because the challenged conduct can have an anticompetitive

effect. Actavis, 570 U.S. at 159. But only a private plaintiff must make an

additional showing that it suffered an antitrust injury (actual or threatened) caused

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by the anticompetitive conduct. See California v. Am. Stores Co., 495 U.S. 271,

295–96 (1990).13

Amgen’s subsequent petitioning does not protect its broader course of

allegedly anticompetitive conduct under Noerr-Pennington. That is so regardless

of whether CareFirst can make a showing of private injury.

The Noerr-Pennington Doctrine Does Not Categorically

Immunize the Acquisition of Rights to a Patent Application.

Amgen separately contends that the acquisition of exclusive rights to patent

applications is categorically protected under Noerr-Pennington because it is

conduct “incidental to petitioning.” Amgen Br. 44. Amgen reasons that because its

deal with Roche was “preliminary” to its subsequent petition to the USPTO,

seeking issuance of the patents, there is “simply no way to disentangle” the two. Id.

at 45–46. This proposed categorical protection is as brazen as it is wrong.

The acquisition of a patent application is a far cry from what courts

traditionally understand as “incidental.” Courts have extended Noerr-Pennington

protection beyond the specific petitioning activity only when necessary to provide

“adequate ‘breathing space’ to the right of petition.” Navient Sols., LLC v. Lohman,

136 F.4th 518, 525 (4th Cir. 2025) (quoting Sosa v. DIRECTV, Inc., 437 F.3d 923,

932 (9th Cir. 2006)). As Amgen acknowledges (Br. 46), that has traditionally been

The FTC takes no position on the requirements for private plaintiff injury.

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necessary only for a narrow category of pre-litigation conduct that has no

independent commercial significance apart from the petition it supports—e.g., the

threat of litigation, offer of settlement, or third-party litigation funding. See Sosa,

437 F.3d at 937; Coastal States Mktg., Inc. v. Hunt, 694 F.2d 1358, 1367–68 (5th

Cir. 1983); Baltimore Scrap Corp. v. David J. Joseph Co., 237 F.3d 394, 401 (4th

Cir. 2001).14

Those limited instances warranted protection under Noerr-Pennington

because the conduct was in service of, and derived its significance from, the

forthcoming petition. The unifying principle is that the conduct exists solely to

initiate, settle, or facilitate a petition—in other words, the conduct is subordinate to

the petitioning.

Amgen’s argument flips that concept on its head. Here, Amgen engaged in a

standalone commercial transaction to acquire an asset that extended its market

power. Petitioning the USPTO was a distinct subsequent step that helped maximize

the financial value of its acquisition. If anything, Amgen’s petitioning is

incidental—and subordinate—to the commercial transaction. It would blink reality

This Court has not yet addressed the scope of “incidental.” See Navient Sols.,

136 F.4th at 525 (leaving “analyzing the exact bounds of Noerr-Pennington

immunity for another day”).

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to suggest that Amgen’s true aspiration was to petition the USPTO, with its

acquisition of the assets a mere expedient towards this ultimate goal.

And critically, even if Amgen never petitioned the USPTO, its acquisition

would retain value separate from any petitioning opportunity. An application’s

owner could sell its rights, license them, or use its ownership strategically to

influence market-entry decisions. See supra Part I.A. By contrast, third-party

litigation funding derives its value strictly from the petitioning activity it supports.

That is why this Court in Baltimore Scrap analogized it to the aid a non-party

provides when filing an amicus brief: both are derivative of and inseparable from

protected petitioning by another party. 237 F.3d at 401. Amgen’s acquisition of

patent applications, by contrast, is distinct from the prosecution of those

applications; it is neither coextensive with nor derivative of petitioning.

Amgen is thus wrong to argue that categorical Noerr-Pennington immunity

for acquisitions of patent applications is necessary to avoid chilling USPTO

petitioning. Amgen Br. 45. Rather, applying the antitrust laws to such transactions

will chill private commercial transactions that increase market power—precisely

the types of agreements the antitrust laws were enacted to prevent.

By way of analogy, consider a hotelier who maintains his monopoly by

purchasing a property to build another hotel. That property has squatters, and the

seller has already initiated eviction proceedings. After purchasing the property, the

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hotelier takes over the squatter eviction proceedings—an act of petitioning. It

would be nonsensical to suggest that the hotelier’s property purchase was merely

“incidental” to removing the squatters. The petitioning is simply a separate step

necessary to maximize the value of the acquired property right. Enforcing the

antitrust laws would not deter the hotelier from evicting squatters; it would only

deter the hotelier from seeking to maintain his monopoly through unlawful land

purchases. The same is true here.

Finally, while Amgen argues that its proposed carveout would be limited to

the acquisition of patent applications, its logic necessarily sweeps far beyond this

case, effectively pulling any standalone commercial transaction under NoerrPennington’s penumbra where petitioning is a foreseeable subsequent step. For

example, the acquisition of a medical device in the FDA approval process would

be incidental to the “petitioning” of seeking approval. Contra Edwards

Lifesciences, 2026 WL 228723 at *46 (acquisition of medical device undergoing

FDA approval process enjoined). Treating these private commercial transactions as

“incidental” would thus impermissibly expand Noerr-Pennington far beyond its

“breathing space,” Navient Sols., 136 F.4th at 525 (cleaned up), rendering the

antitrust laws ineffectual.

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CONCLUSION

The Court should hold (1) that the acquisition of a patent application can

constitute exclusionary conduct under the antitrust laws; and (2) that the presence

of petitioning activity in an overall course of anticompetitive conduct does not

shield the non-petitioning activity from the antitrust laws.

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August 14, 2026

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Respectfully submitted,

LUCAS CROSLOW

General Counsel

H. THOMAS BYRON III

Deputy General Counsel

/s/ Robert A. Silverstein

ROBERT A. SILVERSTEIN

Attorney

Of Counsel:

DANIEL W. BUTRYMOWICZ

ANUPAMA SAWKAR

Attorneys

FEDERAL TRADE COMMISSION

600 Pennsylvania Ave. NW

Washington, D.C. 20580

(202) 325-2488

rsilverstein@ftc.gov

FEDERAL TRADE COMMISSION

Washington, D.C. 20580

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CERTIFICATE OF SERVICE

I hereby certify that on August 14, 2026, I caused the foregoing to be

electronically filed with the Clerk of the Court for the United States Court of

Appeals for the Fourth Circuit by using the appellate CM/ECF system. The

participants in the case are registered CM/ECF users and service will be

accomplished by the appellate CM/ECF system.

Dated: August 14, 2026

/s/ Robert A. Silverstein

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CERTIFICATE OF COMPLIANCE

This brief complies with the length limits of Federal Rule of Appellate

Procedure 29(a)(5). The brief is 6,469 words, excluding the portions exempted by

Rule 32(f). The brief’s typeface and type style comply with Rule 32(a)(5) and (6).

Dated: August 14, 2026

/s/ Robert A. Silverstein

This is a copy of a public record, reproduced as it was published. It is not legal advice, and it may not be the version a court would rely on. Check the official source before you cite it.