Amicus Curiae Brief — HMTX Industries, LLC, et al., Petitioners v. United States, et al.

No. 25-1012

In the Supreme Court of the United States

HMTX INDUSTRIES, LLC, ET AL., PETITIONERS

v.

UNITED STATES, ET AL.

ON PETITION FOR A WRIT OF CERTIORARI

TO THE UNITED STATES COURT OF APPEALS

FOR THE FEDERAL CIRCUIT

BRIEF OF AMICI CURIAE

THE AMERICAN APPAREL & FOOTWEAR

ASSOCIATION, THE CONSUMER

TECHNOLOGY ASSOCIATION, THE

NATIONAL RETAIL FEDERATION, AND THE

RETAIL LITIGATION CENTER, INC.

IN SUPPORT OF PETITIONERS

JOSEPH R. PALMORE

Counsel of Record

ALISON H. HUNG

MORRISON & FOERSTER LLP

2100 L Street NW

Washington, DC 20037

(202) 887-6940

JPalmore@mofo.com

Counsel for Amici Curiae

MARCH 2026

TABLE OF CONTENTS

TABLE OF AUTHORITIES ................................... iii

INTERESTS OF AMICI CURIAE ........................... 1

INTRODUCTION AND SUMMARY OF

ARGUMENT .................................................... 2

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

I.

USTR EXCEEDED ITS STATUTORY

AUTHORITY TO “MODIFY” A SECTION

301 ACTION..................................................... 4

II.

WERE THERE ANY DOUBT ON THE

SCOPE OF USTR’S MODIFICATION

AUTHORITY, THE MAJOR QUESTIONS

DOCTRINE DISPELS IT ................................ 6

A.

This Use of Section 307 Authority Is

Unprecedented And Transformative ....... 7

B.

The Lists 3 And 4A Actions Are Of Vast

Economic And Political Significance

And Have Harmed U.S. Businesses And

Consumers ................................................ 9

C.

USTR Cannot Identify The Clear

Congressional Authorization Needed To

Sustain Lists 3 And 4A .......................... 12

III. ALLOWING USTR TO DRAMATICALLY

EXPAND TARIFF ACTIONS USING

SECTION 307 WOULD IMPERMISSIBLY

CIRCUMVENT SECTION 301’S ROBUST

PROCEDURAL REQUIREMENTS .............. 13

A.

Congress Conditioned USTR’s

Authority To Act Under Section 301 On

Strict Procedural Prerequisites ............. 13

ii

B.

USTR Should Not Be Permitted To Use

Section 307’s Streamlined Modifications

Process To Bypass Section 301’s

Congressionally Imposed Procedural

Safeguards .............................................. 17

C.

This Case Highlights The Inadequacy

Of Section 307 As A Vehicle For

Sweeping Tariff Authority ..................... 19

IV. AFTER LEARNING RESOURCES, THE

QUESTION PRESENTED HAS BECOME

EVEN MORE IMPORTANT ......................... 23

CONCLUSION ....................................................... 26

iii

TABLE OF AUTHORITIES

Cases

Alabama Ass’n of Realtors v. Dep’t of

Health & Hum. Servs.,

594 U.S. 758 (2021) ................................................9

Biden v. Nebraska,

600 U.S. 477 (2023) ................................ 5, 6, 7, 8, 9

FDA v. Brown & Williamson Tobacco

Corp.,

529 U.S. 120 (2000) ................................................6

Learning Res., Inc. v. Trump,

146 S. Ct. 628 (2026) .................. 2, 3, 5, 7, 8, 9, 12,

13, 14, 18, 19, 21

MCI Telecomms. Corp. v. AT&T Co.,

512 U.S. 218 (1994) ................................................5

Util. Air Reg. Grp. v. EPA,

573 U.S. 302 (2014) ................................................7

West Virginia v. EPA,

597 U.S. 697 (2022) .................................... 6, 7, 8, 9

Statutes

19 U.S.C. § 2411 .............................................. 4, 14, 17

19 U.S.C. § 2412 ........................................................14

19 U.S.C. § 2413 ........................................................14

19 U.S.C § 2414 ...................................................14, 17

19 U.S.C § 2417 .....................................................4, 17

iv

Regulatory Materials

Determination of Action to Increase

Duties on Certain Products of

Ukraine Pursuant to Section 301(b),

67 Fed. Reg. 120 (Jan. 2, 2002) ...........................15

Determination of Action to Suspend

GSP Benefits Under Section 301(b),

66 Fed. Reg. 42,246 (Aug. 10, 2001) ....................15

Extension of Public Comment Period,

83 Fed. Reg. 38,760 (Aug. 7, 2018) ......................20

Initiation of Section 301 Investigation,

89 Fed. Reg. 101,088 (Dec. 13, 2024) ..................16

Initiation of Section 302 Investigation,

66 Fed. Reg. 18,346 (Apr. 6, 2001) ......................14

Notice of Action,

90 Fed. Reg. 57,807 (Dec. 12, 2025) ..............16, 17

Notice of Action and Request for Public

Comment Concerning Proposed

Determination of Action Pursuant

to Section 301,

83 Fed. Reg. 28,710 (June 20, 2018) ...................19

Notice of Action Pursuant to Section

301,

83 Fed. Reg. 40,823 (Aug. 16, 2018) ....................20

Notice of Determination and Request

for Comments Concerning Action

Pursuant to Section 301,

90 Fed. Reg. 48,511 (Oct. 23, 2025) .....................16

v

Notice of Determination and Request

for Public Comment Concerning

Proposed Determination of Action

Pursuant to Section 301,

83 Fed. Reg. 14,906 (Apr. 6, 2018) ......................19

Notice of Modification of Section 301

Action,

83 Fed. Reg. 47,974 (Sep. 21, 2018) .......... 5, 20, 22

Notice of Modification of Section 301

Action,

84 Fed. Reg. 20,459 (May 9, 2019) ......................20

Notice of Modification of Section 301

Action,

84 Fed. Reg. 43,304 (Aug. 20, 2019) .......... 5, 20, 22

Notice of Modification of Section 301

Action,

84 Fed. Reg. 45,821 (Aug. 30, 2019) ....................21

Notice of Modification of Section 301

Action,

84 Fed. Reg. 69,447 (Dec. 18, 2019) ....................22

Notice of Rescheduling in the Section

302 Investigation,

66 Fed. Reg. 48,898 (Sept. 24, 2001) ...................15

Request for Comments Concerning

Proposed Modification,

84 Fed. Reg. 22,564 (May 17, 2019) ..............20, 21

Request for Comments Concerning

Proposed Modification of Action

Pursuant to Section 301,

83 Fed. Reg. 33,608 (July 17, 2018) ......................4

vi

Other Authorities

Mary Amiti, Stephen J. Redding &

David E. Weinstein, The Impact of

the 2018 Tariffs on Prices and

Welfare, J. Econ. Persps., Fall 2019 ....................10

Consumer Tech. Ass’n, Analysis of

Section 301 Tariff Impacts on

Imports of Consumer Technology

Products (2022) ....................................................11

Aaron Flaaen & Justin Pierce,

Disentangling the Effects of the

2018-2019 Tariffs on a Globally

Connected U.S. Manufacturing

Sector, Fin. & Econ. Discussion

Series 2019-086 (Dec. 23, 2019) ..........................10

Gary Clyde Hufbauer, Megan Hogan &

Yilin Wang, For Inflation Relief, the

United States Should Look to Trade

Liberalization, Peterson Inst. For

Int'l Econ. (Mar. 2022) .........................................12

Tyler Kendall & Courtney

Subramanian, US Trade Probes Will

Conclude Within Five Months, Greer

Says, Bloomberg (Mar. 3, 2026) ..........................24

Dan Mangan, Trump Administration

Launces Section 301 Trade Probes

into Mexico, China, EU, Others,

CNBC (Mar. 11, 2026) .........................................25

Office of the United States Trade

Representative, 2022 Special 301

Report (2022) ........................................................12

vii

Office of the United States Trade

Representative, Findings of the

Investigation into China’s Acts,

Policies, and Practices Related to

Technology Transfer, Intellectual

Property, and Innovation Under

Section 301 of the Trade Act of 1974

(2018) ....................................................................19

Office of the United States Trade

Representative, Section 301 Docket

(USTR 2018-0026) ...............................................20

Office of the United States Trade

Representative, Section 301 Docket

(USTR 2019-0004) ...............................................20

Office of the United States Trade

Representative, Section 301

Investigation: Report on

Nicaragua's Acts, Policies, and

Practices Related to Labor Rights,

Human Rights and Fundamental

Freedoms, and the Rule of Law (Oct.

20, 2025) ...............................................................16

Press Release, Office of the United

States Trade Representative,

Ambassador Greer Issues Statement

on Supreme Court IEEPA Decision

(Feb. 20, 2026)................................................23, 24

Press Release, Office of the United

States Trade Representative,

Statement by U.S. Trade

Representative Robert Lighthizer on

Section 301 Action (July 10, 2018) ......................21

viii

Press Release, Office of the United

States Trade Representative, USTR

Initiates 60 Section 301

Investigations Relating to Failures

to Take Action on Forced Labor

(Mar. 12, 2026) .....................................................25

Press Release, Office of the United

States Trade Representative, USTR

Initiates Section 301 Investigations

Relating to Structural Excess

Capacity and Production in

Manufacturing Sectors (Mar. 11,

2026) .....................................................................25

Kara M. Reynolds, Costs of Trade Wars:

The Distributional Consequences of

US Section 301 Tariffs Against

China (Am. Univ. Dep’t of Econ.,

Working Paper No. 2022-02, 2021) .....................11

Squawk Box, Watch CNBC’s Full

Interview with Treasury Secretary

Scott Bessent (CNBC, Mar. 4, 2026)....................24

Kate Sullivan, Supreme Court Axes

Tariffs; Trump Responds With New

Rate, Bloomberg (Feb. 20, 2026) .........................23

U.S. Int’l Trade Comm’n, Economic

Impact of Section 232 and 301

Tariffs on U.S. Industries (2023) ........................10

White House, Fact Sheet: President

Donald J. Trump Imposes a

Temporary Import Duty to Address

Fundamental International Payment

Problems (Feb. 20, 2026) .....................................24

INTERESTS OF AMICI CURIAE1

Amici curiae, the American Apparel & Footwear

Association (“AAFA”), the Consumer Technology

Association (“CTA”), the National Retail Federation

(“NRF”), and the Retail Litigation Center, Inc.

(“RLC”), are trade associations whose members have

been harmed by the tariffs at issue here. AAFA; CTA;

NRF; RLC’s affiliate, the Retail Industry Leaders

Association (“RILA”); and the associations’ individual

members submitted comments to the United States

Trade Representative in the Lists 3 and 4

proceedings.

Pursuant to Rule 37.6, amici state that no counsel or

party authored this brief in whole or in part and that no person

other than amici or their counsel made a monetary contribution

to its preparation or submission. Counsel of record for all parties

received notice of this brief at least 10 days before its due date.

1

2

INTRODUCTION AND

SUMMARY OF ARGUMENT

When Congress has delegated its tariff powers,

it has done so in confined situations, subject to strict

constraints. As this Court recently observed, the

tariff provisions of Title 19 of the United States Code

set caps on tariff rates, limit tariffs’ duration, or

condition the imposition of tariffs by the executive on

satisfaction of demanding procedural requirements.

Learning Res., Inc. v. Trump, 146 S. Ct. 628, 639

(2026) (opinion of Roberts, C.J.); see id. at 676-77

(Kagan, J., concurring in part and concurring in the

judgment).

Here, the United States Trade Representative

(“USTR”) sought to evade these congressionally

imposed limits, and the Federal Circuit allowed it to

do so.

Initially, USTR conducted a lengthy

investigation under Section 301 of the Trade Act of

1974 into China’s unfair trade practices and, as a

result, imposed tariffs on $50 billion in Chinese goods

(Lists 1 and 2). However, over a few months in 2018

and 2019, as part of an accelerating trade dispute

with China, USTR purported to exercise its authority

under Section 307 to “modify” its initial Section 301

action and go much further.

These purported

“modifications” were tariffs on another $500 billion

worth of Chinese goods (Lists 3 and 4), reflecting a

ten-fold increase in the initial tariffs.

In imposing the Lists 3 and 4A tariffs, USTR far

exceeded the modest authority Congress granted it

under Section 307. That provision allows USTR

merely to “modify” an action taken under Section 301,

such as by making incremental adjustments to it. It

3

does not authorize USTR to impose massive new

tariffs while skipping over Section 301’s robust

procedural requirements. That is true under a

straightforward statutory construction of the word

“modify.” And it becomes even more true when

applying the major questions doctrine. USTR’s

sweeping assertion of such modification authority is

unprecedented, and the economic significance of these

tariffs is undeniable. If Congress had meant to

delegate to USTR such unbounded power in Section

307, it would have done so clearly.

Amici wish to emphasize the vital importance of

this issue and its far-reaching consequences. The

Lists 3 and 4A tariffs have cost U.S. businesses and

consumers billions of dollars, snarled supply chains,

and hurt employment in multiple sectors. Instead of

instituting these expanded tariffs using Section 301’s

robust process—as Congress had intended—USTR

instead relied on Section 307’s severely truncated

process to vastly increase the tariffs. The Federal

Circuit blessed an interpretation of the statute

allowing USTR to do precisely that—and virtually

ensuring that it will do so again. On the Federal

Circuit’s reading, USTR could bypass the tight

restraints on its Section 301 authority by first

imposing a modest tariff under Section 301, then

ratcheting up the tariff 1,000-fold under Section

307—at any time and for virtually any reason. The

word “modify” in Section 307 “cannot bear such

weight.” Id. at 637.

After Learning Resources, this case has become

even more important.

The Administration has

already stated its intention to fall back on other tariff

statutes, including Section 301 (and by extension

4

Section 307), to effectively reimpose the sweeping

International Emergency Economic Powers Act

(“IEEPA”) tariffs this Court invalidated. In fact,

USTR has already initiated new Section 301

investigations into dozens of countries and declared

that it intends to complete them within five months.

Under the Federal Circuit’s decision here, USTR

could then use Section 307 to repeatedly increase

tariff rates set through the Section 301 process and

extend them to additional imports—unrestrained by

meaningful process or deliberation. The Executive

should not be permitted to exercise such an

extraordinary delegation of Congress’s core taxation

authority without this Court’s review.

ARGUMENT

I.

USTR

EXCEEDED ITS

STATUTORY

AUTHORITY TO “MODIFY” A SECTION

301 ACTION

Section 301 permits USTR to take “appropriate”

action if it determines, after investigation and

consultation, that a foreign country has engaged in

unfair trade practices. 19 U.S.C. § 2411(b). Section

307 in turn permits USTR to “modify or terminate” an

action taken under Section 301 if certain conditions

are met. Id. § 2417(a)(1).

After China retaliated against the Lists 1 and 2

tariffs USTR had previously imposed under Section

301 on $50 billion worth of Chinese goods, USTR

invoked its authority under Section 307 to “modify”

its initial action. Request for Comments Concerning

Proposed Modification of Action Pursuant to Section

301, 83 Fed. Reg. 33,608, 33,609 (July 17, 2018). The

resulting Lists 3 and 4A tariffs were massive—

5

covering $500 billion in goods and virtually all

imports of Chinese products. Notice of Modification

of Section 301 Action, 83 Fed. Reg. 47,974 (Sep. 21,

2018); Notice of Modification of Section 301 Action, 84

Fed. Reg. 43,304 (Aug. 20, 2019).

Those actions exceeded USTR’s limited

modification authority under Section 307. This Court

has made clear that “statutory permission to ‘modify’

does not authorize ‘basic and fundamental changes in

the scheme’ designed by Congress.”

Biden v.

Nebraska, 600 U.S. 477, 494 (2023) (quoting MCI

Telecomms. Corp. v. AT&T Co., 512 U.S. 218, 225

(1994)). The word “‘modify’ connotes ‘increment or

limitation’” and “must be read to mean ‘to change

moderately or in minor fashion.’” Ibid. (quoting MCI,

512 U.S. at 225).

Here, USTR’s Lists 3 and 4A actions were

anything

but

“minor,”

“moderate[],”

or

“increment[al].”

Ibid.

Rather, the purported

“modifications” were breathtaking in scope: they

reflected a ten-fold increase in the original Section

301 action, sweeping in essentially all Chinese

products. Indeed, as explained below, the Lists 3 and

4A tariffs have had a major (and negative) impact on

the American economy. Infra pp. 9-12. By upholding

this use of Section 307, the Federal Circuit essentially

endorsed USTR’s assertion of the power to impose

tariffs on imports “of any product, at any rate, for any

amount of time.” Learning Res., 146 S. Ct. at 637.

Just as the words “regulate” and “importation” could

not support the President’s assertion of unlimited

power to impose IEEPA tariffs, the word “modify” in

Section 307 “cannot bear such weight.” Ibid.

6

II.

WERE THERE ANY DOUBT ON THE

SCOPE OF USTR’S MODIFICATION

AUTHORITY, THE MAJOR QUESTIONS

DOCTRINE DISPELS IT

Even if the statutory construction question were

close, the major questions doctrine would easily tip

the scales against USTR’s position.

This Court has explained that there are “cases in

which the ‘history and the breadth of the authority

that [the agency] has asserted,’ and the ‘economic and

political significance’ of that assertion, provide a

‘reason to hesitate before concluding that Congress’

meant to confer such authority.” West Virginia v.

EPA, 597 U.S. 697, 721 (2022) (alteration in original)

(quoting FDA v. Brown & Williamson Tobacco Corp.,

529 U.S. 120, 159-60 (2000)).

Because

“[e]xtraordinary grants of regulatory authority are

rarely accomplished through modest words, vague

terms, or subtle devices,” this Court “presume[s] that

Congress intends to make major policy decisions

itself, not leave those decisions to agencies.” Id. at

723 (internal quotation marks omitted). Thus, the

Court will “typically greet assertions of extravagant

statutory power over the national economy with

skepticism.” Id. at 724 (internal quotation marks

omitted).

To overcome this skepticism, the agency must

“point to ‘clear congressional authorization’ to justify”

the authority it claims. Biden, 600 U.S. at 506

(quoting West Virginia, 597 U.S. at 723). “Oblique,”

“elliptical,” or “cryptic” words do not suffice. West

Virginia, 597 U.S. at 721, 723.

7

As several Justices recently noted, “[t]hese

considerations apply with particular force where, as

here, the purported delegation involves the core

congressional power of the purse.” Learning Res., 146

S. Ct. at 639 (opinion of Roberts, C.J.). If Congress

were to relinquish its “most complete and effectual

weapon” to another branch, “a reasonable interpreter

would expect it to do so clearly.” Ibid. (internal

quotation marks omitted).

Here, the major questions doctrine confirms that

USTR statutorily overreached. First, as USTR itself

admitted, these tariff actions are unprecedented:

USTR has never invoked Section 307 to expand a

trade action—let alone to this massive degree. C.A.

App. 9778 n.6. Second, as in this Court’s past major

questions cases and Learning Resources, these

challenged actions implicate questions of deep

“economic and political significance.” Learning Res.,

146 S. Ct. at 641 (opinion of Roberts, C.J.) (internal

quotation marks omitted). The tariffs affect virtually

all Chinese imports; they have cost American

businesses billions of dollars, disrupted supply

chains, and raised prices for consumers. Third, USTR

cannot identify in Section 307 “clear congressional

authorization” for such action. Ibid.

A.

This Use of Section 307 Authority Is

Unprecedented And Transformative

In case after case, this Court has declined to

uphold executive assertions of “unheralded” power

over “a significant portion of the American economy.”

West Virginia, 597 U.S. at 722 (quoting Util. Air Reg.

Grp. v. EPA, 573 U.S. 302, 324 (2014)). In Biden v.

Nebraska, for example, the Court declined to read

8

congressional authorization to “‘waive or modify’

existing statutory or regulatory provisions applicable

to financial assistance programs” to encompass the

authority to cancel $430 billion in student loans. 600

U.S. at 494. The Court observed that the Executive

had “never previously claimed powers of this

magnitude” under the statute at issue. Id. at 501.

And in Learning Resources, several Justices

admonished that “[t]he lack of historical precedent for

the IEEPA tariffs, coupled with the breadth of

authority that the President now claims, is a telling

indication that the tariffs extend beyond the

President’s legitimate reach.” 146 S. Ct. at 641

(opinion of Roberts, C.J.) (internal quotation marks

omitted).

Similarly, the “unprecedented nature” and scope

of the authority asserted here should give this Court

“reason to hesitate” before finding the congressional

grant of authority claimed. West Virginia, 597 U.S. at

721.

USTR has never used its Section 307

modification authority to expand a trade action—let

alone by multiple orders of magnitude. In its

contemporaneous internal deliberations, USTR

admitted it was “not aware of prior investigations

where a Trade Representative was called upon to use

Section 307 modification authority to increase the

level of trade action in order to achieve the statutory

goal of obtaining the elimination of harmful policies

covered by the investigation.” C.A. App. 5922. And

in the proceedings below, USTR conceded it has

previously invoked Section 307(a)(1)(C) only “to

reduce, terminate or delay section 301 actions.” C.A.

App. 9778 n.6. For a statute that has been in effect in

its current form for over a quarter century, this

9

historical practice is “telling.” Learning Res., 146 S.

Ct. at 640-41 (opinion of Roberts, C.J.).

Congressional practice confirms the unheralded

nature of the power asserted. As six Justices noted,

“[w]hat Congress has never done in a tariff provision

is *** conferred power on the President to impose a

tariff of any amount, for any time, on only his own

say-so.” Id. at 677 (Kagan, J., concurring in part and

concurring in the judgment); see id. at 639 (opinion of

Roberts, C.J.) (“When Congress has delegated its

tariff powers, it has done so in explicit terms, and

subject to strict limits.”). Yet that is what USTR

effectively claims Congress did here by granting it

boundless “modification” authority.

B.

The Lists 3 And 4A Actions Are Of Vast

Economic And Political Significance

And Have Harmed U.S. Businesses And

Consumers

The “economic and political significance” of the

Lists 3 and 4A tariffs is “staggering by any measure.”

Biden, 600 U.S. at 502 (internal quotation marks

omitted). Lists 3 and 4A covered $500 billion in goods,

representing virtually all Chinese imports. This

Court has applied the major questions doctrine in

cases with “$430 billion,” “nearly $50 billion,” and

“billions of dollars in compliance costs” at stake.

Learning Res., 146 S. Ct. at 641 (opinion of Roberts,

C.J.) (citing Biden, 600 U.S. at 483; Alabama Ass’n of

Realtors v. Dep’t of Health & Hum. Servs., 594 U.S.

758, 764 (2021); and West Virginia, 597 U.S. at 714,

respectively). The stakes here fall comfortably in that

ballpark.

10

When USTR proposed Lists 3 and 4A, numerous

commenters, including amici, their members, and

other businesses, warned that the tariffs would

damage the U.S. economy. They warned that the

tariffs would snarl supply chains, C.A. App. 7396, and

force U.S. businesses either to raise prices or to

absorb the additional costs, C.A. App. 5465. They also

explained that “tariffs simply act as a hidden,

regressive tax on U.S. consumers,” C.A. App. 5467,

disproportionately burdening middle- and low-income

families, C.A. App. 7396.

USTR nonetheless charged ahead, and

commenters’ fears became reality. As the United

States International Trade Commission explained in

a March 2023 report, “the cost of section 301 tariffs

have been borne almost entirely by U.S. importers.” 2

Another study found that, by December 2018, the

2018 tariffs had already cost U.S. importers and

consumers “$3.2 billion per month in added tax costs

and another $1.4 billion per month in deadweight

welfare (efficiency) losses.”3 And a Federal Reserve

study found that exposure to the tariffs has harmed

overall manufacturing employment and resulted in

rising input costs.4

2 U.S. Int’l Trade Comm’n, Economic Impact of Section 232

and 301 Tariffs on U.S. Industries at 145 (2023),

https://www.usitc.gov/publications/332/pub5405.pdf.

3 Mary Amiti, Stephen J. Redding & David E. Weinstein,

The Impact of the 2018 Tariffs on Prices and Welfare, J. Econ.

Persps., Fall 2019, at 187, 188-89, https://www.aeaweb.org/

articles/pdf/doi/10.1257/jep.33.4.187.

4 Aaron Flaaen & Justin Pierce, Disentangling the Effects

of the 2018-2019 Tariffs on a Globally Connected U.S.

11

These negative effects have been felt by U.S.

businesses across many sectors. Amicus Consumer

Technology Association, for example, observed in July

2022 that “[m]ost of the tech products that have faced

the highest Section 301 tariffs are on List 3”5 and that

consumer technology manufacturing jobs had

performed “much worse” since the tariffs were

imposed.6

At that time, consumer technology

companies had paid an estimated $40 billion in

Section 307 tariffs, diverting funds from research and

development or job creation.7

The tariffs also have harmed U.S. consumers.

One study found that the tariffs had cost the average

U.S. household “at least $160 per year” and

disproportionately burdened low-income consumers,

families with young children, and women.8 Another

analysis found that trade liberalization “could deliver

a one-time reduction in consumer price index (CPI)

Manufacturing Sector 3, Fin. & Econ. Discussion Series 2019086 (Dec. 23, 2019), https://doi.org/10.17016/FEDS.2019.086.

Consumer Tech. Ass’n, Analysis of Section 301 Tariff

Impacts on Imports of Consumer Technology Products 9 (2022),

https://www.wita.org/wp-content/uploads/2022/08/CTA_Section301-Tariff-Whitepaper.pdf.

5

6 See id. at 15.

7 Id. at 2.

Kara M. Reynolds, Costs of Trade Wars: The

Distributional Consequences of US Section 301 Tariffs Against

China 1 (Am. Univ. Dep’t of Econ., Working Paper No. 2022-02,

2021),

https://edspace.american.edu/reynolds/wp-content/

uploads/sites/1780/2021/06/DistributionalCosts.pdf.

8

12

inflation of around 1.3 percentage points,” amounting

to relief of “$797 per US household.”9

Nor have the Section 307 tariffs been effective in

eliminating forced technology transfers and creating

a level playing field for IP protection and

enforcement—the practices the original Section 301

tariffs had targeted in the first place. Despite the

tariffs, USTR subsequently noted only minimal

progress on these issues, while highlighting

continuing concerns about China’s unfair trade

practices.10

C.

USTR Cannot Identify The Clear

Congressional Authorization Needed

To Sustain Lists 3 And 4A

USTR also cannot “point to clear congressional

authorization” to justify its “extraordinary” use of

Section 307. Learning Res., 146 S. Ct. at 642 (opinion

of Roberts, C.J.) (citation omitted).

As shown above, Section 307’s authority to

“modify” a Section 301 action does not grant USTR

the power to escalate that action into a full-blown

trade war. Supra pp. 4-5. Rather, and as USTR’s

historical practice confirms, the word “modify” in

Section 307 is naturally understood as a grant of

cabined authority to make modest adjustments to an

9 Gary Clyde Hufbauer, Megan Hogan & Yilin Wang, For

Inflation Relief, the United States Should Look to Trade

Liberalization 1, Peterson Inst. For Int’l Econ. (Mar. 2022),

https://www.piie.com/sites/default/files/documents/pb22-4.pdf.

See USTR, 2022 Special 301 Report 44-53 (2022),

https://ustr.gov/sites/default/files/IssueAreas/IP/2022%20Specia

l%20301%20Report.pdf.

10

13

initial Section 301 action. Had Congress truly

intended to convey in Section 307 such extraordinary

power, “it would have done so expressly.” Learning

Res., 146 S. Ct. at 642.

III. ALLOWING USTR TO DRAMATICALLY

EXPAND

TARIFF

ACTIONS

USING

SECTION 307 WOULD IMPERMISSIBLY

CIRCUMVENT SECTION 301’S ROBUST

PROCEDURAL REQUIREMENTS

Section 307 lacks not only the clear

congressional authorization required to justify the

power claimed but also the rigorous procedural

conditions attached to other statutory provisions

granting executive tariff authority, including Section

301. The rushed Lists 3 and 4A process here

illustrates that difference and confirms that Congress

did not intend Section 307 to authorize the

unbounded authority USTR asserts.

Amici do not challenge USTR’s authority to

impose tariffs under Section 301. In fact, the business

community at times may support certain Section 301

actions—so long as USTR faithfully complies with all

the procedural safeguards Congress imposed. What

amici object to here is USTR’s unprecedented use of

Section 307 to explode a trade action and circumvent

Section 301’s guardrails.

A.

Congress

Conditioned

USTR’s

Authority To Act Under Section 301 On

Strict Procedural Prerequisites

As several Justices recently recognized, Title

19’s tariff provisions are “carefully confined.”

Learning Res., 146 S. Ct. at 677 (Kagan, J., concurring

14

in part and concurring in the judgment). “[I]n each

and every instance” Congress has delegated that

authority, it has “imposed tight restraints on the

power given.” Ibid.; see id. at 639 (opinion of Roberts,

C.J.) (“When Congress has delegated its tariff powers,

it has done so in explicit terms, and subject to strict

limits.”). And for good reason: as discussed (supra

p. 7), a “reasonable interpreter” would expect

Congress to jealously guard its “most complete and

effectual weapon” and exercise caution in delegating

the “core congressional power of the purse.” Learning

Res., 146 S. Ct. at 639 (opinion of Roberts, C.J.)

(internal quotation marks omitted).

Turning to the provisions at issue here:

Congress permits USTR to impose tariffs under

Section 301(b), 19 U.S.C. § 2411(b), but only after

USTR has satisfied a series of “demanding procedural

prerequisites,” Learning Resources, 146 S. Ct. at 639

(opinion of Roberts, C.J.) (discussing, among other

provisions, Section 301). Those requirements include:

investigation, 19 U.S.C. § 2412; consultations with

the relevant country and interested parties, id.

§ 2413; written factual findings, id. § 2414(c); notice

and opportunities to comment, id. § 2414(b); and a

twelve-month deadline to determine “appropriate”

action, id. §§ 2411(b)(2), 2414(a)(2)(B).

Examining how two prior Section 301 processes

have unfolded demonstrates how demanding, timeintensive, and solicitous of public input these

congressionally imposed guardrails can be in practice.

Ukraine, 2001: In March 2001, USTR initiated

a Section 301 investigation into Ukraine’s trade

practices. Initiation of Section 302 Investigation, 66

15

Fed. Reg. 18,346, 18,346 (Apr. 6, 2001). USTR

conducted a public hearing and received comments on

the issues under investigation. Determination of

Action to Suspend GSP Benefits Under Section

301(b), 66 Fed. Reg. 42,246, 42,247 (Aug. 10, 2001).

USTR determined it would impose tariffs on

Ukrainian products and published a preliminary list

of products under consideration. Id. at 42,246-42,247.

It invited public comment on the proposed list, with

rebuttal comments due September 28, 2001. Id. at

42,247; Notice of Rescheduling in the Section 302

Investigation, 66 Fed. Reg. 48,898 (Sept. 24, 2001).

USTR later extended the investigation by three

months because “the development of the final product

list involved complex and complicated issues that

required additional time.” Determination of Action to

Increase Duties on Certain Products of Ukraine

Pursuant to Section 301(b), 67 Fed. Reg. 120, 120

(Jan. 2, 2002). On December 21, 2001, USTR

announced the final product list subject to tariffs.

Ibid. The final list was much shorter than the

proposed one: for example, titanium oxides, clothing,

iron, nonalloy steel, snow skis, and hockey equipment

were omitted from the final list.11 Over nine months

elapsed between USTR’s initiating the investigation

and finalizing the tariffs, and over three months

between the comment deadline on the proposed tariffs

and their finalization.

Contrast Determination of Action to Suspend GSP

Benefits Under Section 301(b), 66 Fed. Reg. at 42,248-42,250

(proposed tariff list), with Determination of Action to Increase

Duties on Ukraine Pursuant to Section 301(b), 67 Fed. Reg. at

121 (final tariff list).

11

16

Nicaragua, 2024-2025: In December 2024,

USTR initiated a Section 301 investigation into

Nicaragua’s policies “related to labor rights, human

rights, and the rule of law.” Initiation of Section 301

Investigation, 89 Fed. Reg. 101,088, 101,089 (Dec. 13,

2024).

Based on its investigation, review of

comments, and consideration of public hearing

testimony, USTR proposed, among other actions,

suspending an existing trade agreement’s benefits to

Nicaragua and “applying tariffs of up to 100 percent

on all Nicaraguan imports, immediately or phased in

over a period of time up to 12 months.” Notice of

Determination

and

Request

for

Comments

Concerning Action Pursuant to Section 301, 90 Fed.

Reg. 48,511, 48,512-48,513 (Oct. 23, 2025). USTR

also issued a comprehensive report on the

investigation12 and again requested comment, ibid.

In response, USTR received over 2,000 written

comments.

Commenters opposing the proposed

actions expressed concern about their broad scope,

asserting that they would hurt U.S. consumers and

workers and disrupt supply chains. Notice of Action,

90 Fed. Reg. 57,807, 57,808-57,809 (Dec. 12, 2025).

USTR’s final determination considered and

addressed “the many comments that expressed

concern regarding the possible impact and disruption

to U.S. interests of taking broad action.” Id. at 57,809.

On December 12, 2025, it announced a 15% tariff on

12 USTR, Section 301 Investigation:

Report on Nicaragua’s

Acts, Policies, and Practices Related to Labor Rights, Human

Rights and Fundamental Freedoms, and the Rule of Law (Oct.

20, 2025), https://ustr.gov/sites/default/files/files/Press/Releases/

2025/Nicaragua%20Section%20301%20Report_0.pdf.

17

all Nicaraguan goods not covered by the existing trade

agreement, phased-in over two years. Id. at 57,808.

“[L]imiting the tariffs to goods” not covered by the

trade agreement, USTR explained, “should limit the

impact on U.S. exports to Nicaragua and U.S.

companies producing in Nicaragua,” while still

putting pressure on Nicaragua to eliminate its

actionable policies. Ibid. And “the two-year phase-in

should provide companies with the time to shift

operations to other” countries. Ibid. It took USTR

twelve months after it initiated the investigation to

finalize these actions.

B.

USTR Should Not Be Permitted

To Use Section 307’s Streamlined

Modifications Process To Bypass

Section 301’s Congressionally Imposed

Procedural Safeguards

In comparison, the truncated process under

Section 307 carries limited procedural safeguards. It

requires no additional investigation or factfinding

before USTR may “modify” the original Section 301

action. See 19 U.S.C. § 2417(a). Under Section 307,

all USTR must do is “consult” with representatives of

the domestic industry affected and provide parties an

opportunity to comment. Id. § 2417(a)(2). And as

USTR stated below, while “an initial Section 301

action generally must be accompanied by a minimum

30-day notice period,” Congress “omitted any such

requirement” for a Section 307 modification. USTR

C.A. Br. 49-50 (citing 19 U.S.C. §§ 2411(b),

2414(b)(1)(A), 2417(a)(2)). This all makes sense if, as

USTR’s historical practice confirms, Congress

intended Section 307 to enable USTR only to modify—

18

namely, make modest adjustments to—an initial

Section 301 action.

But given that Congress conditioned USTR’s

authority to take an initial Section 301 action on strict

procedural requirements, it makes no sense for

Congress to have granted USTR “power to

unilaterally impose tariffs of unlimited amount,

duration, and scope” through USTR’s Section 307

modification authority, which is subject to far fewer

procedural requirements. Cf. Learning Res., 146 S.

Ct. at 646 (declining to read into IEEPA a grant of

such unlimited tariff authority). Yet that is what the

decision below, taken to its logical conclusion, says

Congress did. On the Federal Circuit’s reading,

USTR could first impose inconsequential tariffs under

Section 301, such that few would think to comment;

then, using Section 307, USTR could “modify” those

tariffs and increase them 1,000-fold. USTR would be

“unconstrained by the significant procedural

limitations” in Section 301 “and free to issue a

dizzying array of modifications at will.” Id. at 640

(opinion of Roberts, C.J.). And because Section 307—

unlike Section 301—requires so little process, affected

parties would have difficulty finding any basis to

challenge the purported “modifications,” however

baseless or unconstrained.

Thus, if left to stand, the decision below would

bless USTR’s end-run around Section 301’s important

procedural safeguards. Any Administration could

“escape the rigors” of Section 301 simply by citing

some

attenuated

connection

between

the

“modification” and the initial Section 301 action. Id.

at 677 (Kagan, J., concurring in part and concurring

in the judgment). USTR’s approach could also create

19

perverse incentives for businesses by forcing them to

challenge every Section 301 action, no matter how

insignificant, for fear that USTR would drastically

increase the actions later under Section 307. This

“gutting” of Title 19’s “carefully confined” tariff

scheme is not what Congress “could have meant to

accomplish” in granting USTR the limited authority

to modify an initial Section 301 action. Ibid.

C.

This Case Highlights The Inadequacy

Of Section 307 As A Vehicle For

Sweeping Tariff Authority

The experiences of the business community

(including amici’s members) with the Lists 3 and 4A

tariffs illustrate how inadequate the truncated

Section 307 process is for such sweeping actions.

In comparison, the Lists 1 and 2 process was

significantly more robust. After a seven-month

Section 301 investigation, USTR published a detailed,

almost 200-page factfinding report.13 It then issued

notice of its determination that the investigated

practices were actionable and requested public

comment on the proposed Lists 1 and 2. Notice of

Determination and Request for Public Comment

Concerning Proposed Determination of Action

Pursuant to Section 301, 83 Fed. Reg. 14,906, 14,90614,954 (Apr. 6, 2018). USTR published notice of final

List 1 on June 20, 2018, and final List 2 on August 16,

2018. Notice of Action and Request for Public

13 USTR, Findings of the Investigation into China’s Acts,

Policies, and Practices Related to Technology Transfer,

Intellectual Property, and Innovation Under Section 301 of the

Trade Act of 1974 (2018), https://ustr.gov/sites/default/files

/Section%20301%20FINAL.PDF.

20

Comment Concerning Proposed Determination of

Action Pursuant to Section 301, 83 Fed. Reg. 28,710,

28,711 (June 20, 2018); Notice of Action Pursuant to

Section 301, 83 Fed. Reg. 40,823, 40,823-40,824 (Aug.

16, 2018). List 1 was finalized ten months after the

Section 301 investigation was initiated; List 2 was

finalized twelve months after the investigation was

initiated.

The Lists 3 and 4A process took less than half

the time. When USTR proposed the tariffs, it received

around 9,000 comments, nearly all expressing serious

concerns about the proposed actions.14 But despite

the breathtaking scope of the proposed tariffs and the

volume of comments received, USTR rushed to impose

the final tariffs. The List 3 tariffs were finalized just

66 days after they were proposed and just eleven days

after written comments were due, Notice of

Modification of Section 301 Action, 83 Fed. Reg. at

47,974; Extension of Public Comment Period, 83 Fed.

Reg. 38,760, 38,761 (Aug. 7, 2018); the List 4 tariffs

just 95 days after they were proposed and just over a

month after comments were due, Notice of

Modification of Section 301 Action, 84 Fed. Reg. at

43,304; Request for Comments Concerning Proposed

Modification, 84 Fed. Reg. 22,564, 22,564 (May 17,

2019).

Eight months after finalizing List 3, and without

receiving any further comments, USTR increased the

See USTR, Section 301 Docket (USTR 2018-0026),

https://www.regulations.gov/docket/USTR-2018-0026

(last

visited Mar. 26, 2026), (List 3); USTR, Section 301 Docket (USTR

2019-0004),

https://www.regulations.gov/docket/USTR-20190004 (last visited Mar. 26, 2026) (List 4).

14

21

duty rate on List 3 products from 10% to 25%. Notice

of Modification of Section 301 Action, 84 Fed. Reg.

20,459, 20,459-20,460 (May 9, 2019). And just ten

days after finalizing List 4, and again without

receiving any further comments, USTR increased the

rate on List 4 products from 10% to 15%. Notice of

Modification of Section 301 Action, 84 Fed. Reg.

45,821 (Aug. 30, 2019).

These unilateral rate

adjustments illustrate USTR’s willingness to use

Section 307 to make significant decisions on little

more than a whim. Cf. Learning Res., 146 S. Ct. at

640 (opinion of Roberts, C.J.) (“On this reading, ***

the President is unconstrained by the significant

procedural limitations in other tariff statutes and free

to issue a dizzying array of modifications at will.”).

What is more, in imposing the Lists 3 and 4A

“modifications,” USTR explicitly relied on China’s

imposition of retaliatory tariffs on U.S. products—not

any increased burdens or restrictions arising from the

practices that USTR sought to address through its

initial Section 301 actions.15 This demonstrates

USTR’s willingness to invoke Section 307 on grounds

separate from the unfair trade practices that gave rise

to the initial Section 301 actions, further

Press Release, USTR, Statement by U.S. Trade

Representative Robert Lighthizer on Section 301 Action (July

10, 2018), https://ustr.gov/about-us/policy-offices/press-office/

pressreleases/2018/july/statement-us-trade-representative

(citing China’s “retaliation” in announcing the proposed List 3

tariffs); Requests for Comments Concerning Proposed

Modification, 84 Fed. Reg. at 22,564 (citing China’s “response to

the current action being taken in this investigation” in proposing

List 4 tariffs).

15

22

underscoring the unbounded nature of the Section

307 authority USTR claims.

In finalizing Lists 3 and 4A, USTR failed to

respond to a single comment, aside from conclusory

assertions that its determinations “take[] account of

the public comments.” Notice of Modification of

Section 301 Action, 84 Fed. Reg. at 43,305; see Notice

of Modification of Section 301 Action, 83 Fed. Reg. at

47,975 (claiming USTR had “carefully reviewed the

public comments”).16 USTR’s process in finalizing

Lists 3 and 4A was so inadequate that the Court of

International Trade (“CIT”), in its first opinion, found

that USTR’s failure to respond to comments violated

the Administrative Procedure Act. Pet. App. 88a-98a.

The CIT noted that “[t]he standard that an agency’s

response must meet is not particularly demanding.”

Pet. App. 88a (internal quotation marks omitted).

But it nonetheless concluded that USTR’s (lack of)

response to comments on proposed Lists 3 and 4A fell

short of even that low bar. On List 3, USTR “fail[ed]

to apprise the court of the rationale for the product

selection and how that rationale is responsive to the

comments.” Pet. App. 96a. On List 4A, USTR “failed

to connect the removal of subheadings to the

comments or address comments that, for example,

16 List 4 was implemented in two tranches, Lists 4A and

4B. Notice of Modification of Section 301 Action, 84 Fed. Reg. at

43,305.

List 4B’s imposition was eventually suspended

indefinitely in a trade deal with China. Notice of Modification of

Section 301 Action, 84 Fed. Reg. 69,447, 69,447 (Dec. 18, 2019).

23

urged the USTR to distinguish between parts and

finished goods.” Pet. App. 97a.17

IV. AFTER LEARNING RESOURCES, THE

QUESTION PRESENTED HAS BECOME

EVEN MORE IMPORTANT

As petitioners explain, the question presented

was important even before Learning Resources

because of the Lists 3 and 4A tariffs’ massive

economic impacts and the future ramifications of the

Federal Circuit’s decision. Pet. 30-33.

But this case has become even more important

after that decision because the Administration has

made clear that Section 301 will feature prominently

in its efforts to reimpose the sweeping tariffs this

Court invalidated. After Learning Resources, the

Administration confirmed it would fall back on

Section 301, among other tariff provisions, to “ensure

continuity” in achieving its trade goals.18 President

The CIT remanded to give USTR a second chance to

explain its decisions. Pet. App. 98a-102a. The CIT subsequently

found USTR’s explanation on remand adequate to support Lists

3 and 4, and the Federal Circuit affirmed that finding. Pet. App.

117a-136a (CIT); Pet. App. 30a-38a (Fed. Cir.). The Federal

Circuit’s blessing of USTR’s truncated and inadequate Section

307 process will increase businesses’ perverse incentives to

oppose even limited Section 301 actions out of fear they will later

be dramatically increased without meaningful opportunity for

input. See supra pp. 18-19.

17

Press Release, USTR, Ambassador Greer Issues

Statement on Supreme Court IEEPA Decision (Feb. 20, 2026),

https://ustr.gov/about/policy-offices/press-office/pressreleases/2026/february/ambassador-greer-issues-statementsupreme-court-ieepa-decision

[hereinafter

“USTR

Press

Release”]; see, e.g., Kate Sullivan, Supreme Court Axes Tariffs;

Trump Responds With New Rate, Bloomberg (Feb. 20, 2026),

18

24

Trump immediately imposed a temporary 10% global

import tariff, invoking his authority under a different

statute (Section 122), which caps tariffs’ duration at

150 days.19 USTR also vowed to “[i]nitiate several

investigations under Section 301” “on an accelerated

timeframe” to address allegedly unfair trade

practices.20 It stated that these investigations would

target “most major trading partners” and a broad set

of issues.21 USTR subsequently announced it would

complete the Section 301 investigations needed to

impose new tariffs “to replace the levies struck down

by the Supreme Court” “within five months.”22 The

Treasury Secretary confirmed that the Section 122

tariffs temporarily imposed by the President will

endure and expand once USTR completes its Section

301 investigations, expressing his “strong belief that

https://www.bloomberg.com/news/articles/2026-02-20/trump-tohold-press-briefing-following-court-s-tariff-ruling.

The White House, Fact Sheet: President Donald J.

Trump Imposes a Temporary Import Duty to Address

Fundamental International Payment Problems (Feb. 20, 2026),

https://www.whitehouse.gov/fact-sheets/2026/02/fact-sheetpresident-donald-j-trump-imposes-a-temporary-import-duty-toaddress-fundamental-international-payment-problems/.

19

20 USTR Press Release.

21 Ibid.

Tyler Kendall & Courtney Subramanian, US Trade

Probes Will Conclude Within Five Months, Greer Says,

Bloomberg (Mar. 3, 2026), https://www.bloomberg.com/news

/articles/2026-03-03/us-trade-probes-will-conclude-within-fivemonths-greer-says.

22

25

the tariff rates will be back to their old rate within

five months.”23

On March 11, USTR initiated a slew of Section

301 investigations into 16 countries.24 It added that

“there will be other Section 301 investigations on a

country-specific basis, or maybe other tools or

investigations that may come up.”25 The next day, it

initiated

additional

sweeping

Section

301

26

investigations into 60 more countries.

If the decision below is left uncorrected, nothing

would keep USTR from repeatedly following this

case’s playbook: initiate Section 301 investigations

into dozens of countries (as it already has done in its

effort to replicate the IEEPA tariffs), impose modest

tariffs under Section 301 on imports from those

Squawk Box, Watch CNBC’s Full Interview with

Treasury Secretary Scott Bessent, at 13:41-14:27 (CNBC, Mar. 4,

2026), https://www.cnbc.com/video/2026/03/04/watch-cnbcs-fullinterview-with-treasury-secretary-scott-bessent.html.

23

24 Press Release, USTR, USTR Initiates Section 301

Investigations Relating to Structural Excess Capacity and

Production in Manufacturing Sectors (Mar. 11, 2026),

https://ustr.gov/about/policy-offices/press-office/pressreleases/2026/march/ustr-initiates-section-301-investigationsrelating-structural-excess-capacity-and-production.

25 Dan Mangan, Trump Administration Launces Section

301 Trade Probes into Mexico, China, EU, Others, CNBC (Mar.

11,

2026),

https://www.cnbc.com/2026/03/11/trump-tradeinvestigations-ieepa-tariffs.html

Press Release, USTR, USTR Initiates 60 Section 301

Investigations Relating to Failures to Take Action on Forced

Labor (Mar. 12, 2026), https://ustr.gov/about/policy-offices/pressoffice/press-releases/2026/march/ustr-initiates-60-section-301investigations-relating-failures-take-action-forced-labor.

26

26

countries, then use Section 307 to expand those tariffs

ten-, 100-, or 1,000-fold while bypassing Section 301’s

strict prerequisites.

Given the new prominence of Section 301 (and,

by extension, Section 307), it is critical for this Court

to address the scope of USTR’s Section 307

modification authority and what, if any, limits it

imposes. This case provides an ideal vehicle for the

Court to do so.

CONCLUSION

The petition should be granted.

Respectfully submitted,

JOSEPH R. PALMORE

Counsel of Record

ALISON H. HUNG

MORRISON & FOERSTER LLP

2100 L Street NW

Washington, DC 20037

(202) 887-6940

JPalmore@mofo.com

Counsel for Amici Curiae

MARCH 2026