Amicus Curiae Brief — Laboratory Corporation of America Holdings, dba Labcorp, Petitioner v. Luke Davis, et al.

No. 24-304

In the

Supreme Court of the United States

LABORATORY CORPORATION OF AMERICA

HOLDINGS, DBA LABCORP,

Petitioner,

v.

LUKE DAVIS, et al.,

Respondents.

On Writ of Certiorari to the

United States Court of A ppeals for the Ninth Circuit

BRIEF OF PROFESSORS WILLIAM B.

RUBENSTEIN AND ARTHUR R. MILLER

AS AMICI CURIAE IN SUPPORT OF

NEITHER PARTY

William B. Rubenstein

Counsel of Record

1545 Massachusetts Avenue

Cambridge, MA 02138

(617) 496-7320

rubenstein@law.harvard.edu

Counsel for Amici Curiae

120299

A

(800) 274-3321 • (800) 359-6859

i

TABLE OF CONTENTS

Page

TABLE OF CONTENTS . . . . . . . . . . . . . . . . . . . . . . . . . . i

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

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

SUMMARY OF ARGUMENT . . . . . . . . . . . . . . . . . . . . 2

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

I.

Class Members Can Neither Borrow

Standing From One Another Nor Destroy

One Another’s Standing . . . . . . . . . . . . . . . . . . . . 6

II. The Predominance Issue Is Not One of

Quantity but Ease of Removal . . . . . . . . . . . . . . 14

III. Defendants’ Interests Are More Mixed Than

Petitioner Portrays . . . . . . . . . . . . . . . . . . . . . . . . 17

CONCLUSION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

ii

TABLE OF CITED AUTHORITIES

Page

CASES:

Alexander v. C.R. Bard, Inc.,

No. 12-cv-5187, 2014 WL 12602871

(N.D. Tex. Feb. 26, 2014) . . . . . . . . . . . . . . . . . . . . . . 12

Amchem Prods., Inc. v. Windsor,

521 U.S. 591 (1997) . . . . . . . . . . . . . . . . . . . 5, 14, 19, 20

Boyd v. Seterus, Inc.,

No. CV-17-76-GW, 2017 WL 8110070

(C.D. Cal. Mar. 30, 2017) . . . . . . . . . . . . . . . . . . . . . . . 12

Charlatan v. Clayton Cnty. Gov’t,

No. 19-CV-00199, 2020 WL 9598956 (M.D. Ga.

Nov. 23, 2020), report and recommendation

adopted, No. 19-CV-00199, 2021 WL 1976631

(M.D. Ga. Apr. 20, 2021) . . . . . . . . . . . . . . . . . . . . . . . 12

In re Asacol Antitrust Litig.,

907 F.3d 42 (1st Cir. 2018) . . . . . . . . . . . . . . . . . . . . . 15

In re Deepwater Horizon,

744 F.3d 370 (5th Cir. 2014) . . . . . . . . . . . . . . . . . . . . 19

In re Hyundai & Kia Fuel Econ. Litig.,

926 F.3d 539 (9th Cir. 2019) . . . . . . . . . . . . . . . . . . . . 20

In re Literary Works in Elec. Databases

Copyright Litig.,

509 F.3d 116 (2d Cir. 2007) . . . . . . . . . . . . . . . . . . . . . 18

iii

Cited Authorities

Page

In re Nexium Antitrust Litig.,

777 F.3d 9 (1st Cir. 2015) . . . . . . . . . . . . . . . . . . . . . . 15

In re: Oil Spill by the Oil Rig “Deepwater Horizon”

in the Gulf of Mexico, on April 20, 2010,

910 F. Supp. 2d 891 (E.D. La. 2012) (appendix B),

aff’d sub nom. In re Deepwater Horizon,

739 F.3d 790 (5th Cir. 2014) . . . . . . . . . . . . . . . . . . . . 19

In re Rail Freight Fuel Surcharge Antitrust Litig.,

934 F.3d 619 (D.C. Cir. 2019) . . . . . . . . . . . . . . . . . . . 15

In re S. Cent. States Bakery Prods. Antitrust Litig.,

86 F.R.D. 407 (M.D. La. 1980) . . . . . . . . . . . . . . . . . . 17

In re Visa Check/MasterMoney Antitrust Litig.,

280 F.3d 124 (2d Cir. 2001) . . . . . . . . . . . . . . . . . . . . . 16

Lewis v. Casey,

518 U.S. 343 (1996) . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

Microsoft Corp. v. Baker,

582 U.S. 23 (2017) . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

Mullaney v. Anderson,

342 U.S. 415 (1952) . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

O’Shea v. Littleton,

414 U.S. 488 (1974) . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

Reed Elsevier, Inc. v. Muchnick,

559 U.S. 154 (2010) . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

iv

Cited Authorities

Page

Sierra Club v. Morton,

405 U.S. 727 (1972) . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

Simon v. E. Ky. Welfare Rts. Org.,

426 U.S. 26 (1976) . . . . . . . . . . . . . . . . . . . . . . . . . . . 2, 7

Soc’y of Eur. Stage Authors & Composers v.

WCAU Broad. Co.,

1 F.R.D. 264 (E.D. Pa. 1940) . . . . . . . . . . . . . . . . . . . 10

Spokeo, Inc. v. Robins,

578 U.S. 330 (2016) . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

TransUnion LLC v. Ramirez,

594 U.S. 413 (2021) . . . . . . . . . . . . . . . . . . . . . . . 5, 6, 14

Tyson Foods, Inc. v. Bouaphakeo,

577 U.S. 442 (2016) . . . . . . . . . . . . . . . . . . . . . . . . . 6, 14

Uniloc 2017, LLC v. Google LLC,

No. 18-cv-00496, 2019 WL 6006228 (E.D. Tex.

Aug. 16, 2019), report and recommendation

adopted, No. 18-cv-00496, 2019 WL 6002210

(E.D. Tex. Sept. 10, 2019) . . . . . . . . . . . . . . . . . . . . . . 12

Wal-Mart Stores, Inc. v. Dukes,

564 U.S. 338 (2011) . . . . . . . . . . . . . . . . . . . . . . . . . 3, 13

Warth v. Seldin,

422 U.S. 490 (1975) . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

v

Cited Authorities

Page

STATUTES AND OTHER AUTHORITIES:

U.S. Const. art. III . . . . . . . . . . . . . . . . . . . . . 2-6, 13-16, 21

28 U.S.C. § 2072(b) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

Fed. R. Civ. P. 13 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

Fed. R. Civ. P. 14 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

Fed. R. Civ. P. 17 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

Fed. R. Civ. P. 18 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2, 7

Fed. R. Civ. P. 19 . . . . . . . . . . . . . . . . . . . . . . . . . . . 9, 10, 12

Fed. R. Civ. P. 20 . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2, 7, 10

Fed. R. Civ. P. 21 . . . . . . . . . . . . . . . . . . . . . . . . 3, 7, 9-13, 16

Fed. R. Civ. P. 21 advisory committee’s note . . . . . . . . . 9

Fed. R. Civ. P. 23 . . . . . . . . . . . 1-4, 6, 7, 9-11, 13-16, 19, 20

Fed. R. Eq. 43 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9, 11

Fed. R. Eq. 44 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

vi

Cited Authorities

Page

Henry Greening & J. C. Perkins, Chitty’s

Treatise on Pleading and Parties to Actions,

with a Second Volume Containing Modern

Precedents of Pleadings, and Practical Notes

(Springfield, G. & C. Merriam 1882) . . . . . . . . . . . . . .8

Geoffrey C. Hazard, Jr., Indispensable Party:

The Historical Original of a Procedural

Phantom, 61 Colum. L. Rev. 1254 (1961) . . . . . . . . . . 9

James Love Hopkins, The New Federal Equity

Rules (8th ed. 1933) . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

Pr o c e d u r a l G ui d a n c e fo r C l a ss Ac ti o n

Settlements, U.S. Dist. Ct., N. Dist. of

Cal. (last modified Sept. 5, 2024), https://

w w w.cand.uscourts.gov/forms/proceduralguidance-for-class-action-settlements/ . . . . . . . . . . 18

Morris A. Ratner, Class Conflicts, 92 Wash. L.

Rev. 785 (2017) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

D. Theodore Rave, Closure Provisions in MDL

Settlements, 85 Fordham L. Rev. 2175 (2017) . . . . . 17

Barbara J. Rothstein & Thomas E. Willging,

Managing Class Action Litigation: A Pocket

Guide for Judges (3d ed. 2010) . . . . . . . . . . . . . . . . . 18

William B. Rubenstein, Newberg and Rubenstein

on Class Actions (6th ed. 2022) . . . . . . . . . . 3, 4, 11, 20

vii

Cited Authorities

Page

Charles Silver, “We’re Scared to Death”: Class

Certification and Blackmail, 78 N.Y.U. L. Rev.

1357 (2003) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

Edson R. Sunderland, Joinder of Actions,

18 Mich. L. Rev. 571 (1920) . . . . . . . . . . . . . . . . . . . . . 8

Charles Alan Wright, Arthur R. Miller, Mary Kay

Kane, & Howard M. Erichson, Federal Practice

and Procedure (3d ed. 2024) . . . . . . . . . . . . . . . 8-10, 12

Stephen C. Yeazell, From Medieval Group

Litigation to the Modern Class Action (1987) . . . . . 9

1

INTEREST OF AMICI CURIAE1

Amicus William B. Rubenstein is the Bruce Bromley

Professor of Law at Harvard Law School. Since 2008,

Professor Rubenstein has been the sole author of the

leading treatise on class action law in the United States,

now called Newberg and Rubenstein on Class Actions.

Amicus Arthur R. Miller is a University Professor

and Warren E. Burger Professor of Constitutional Law

and Courts at New York University Law School. From

1986–2007, Professor Miller was the Bruce Bromley

Professor of Law at Harvard Law School. Professor Miller

assisted in the drafting of the 1966 amendments to the

Federal Rules of Civil Procedure, which introduced the

modern version of Rule 23. For more than half a century,

Professor Miller has been the co-author of Wright &

Miller’s Federal Practice and Procedure, the leading

treatise on civil procedure, criminal procedure, and

evidence, in the United States.

Amici respectfully submit this brief to identify

several issues missing from consideration in the lower

court decisions and present party submissions to date,

specifically: (1) the history underlying the joinder-based

nature of the question presented; (2) the proper focus of the

predominance inquiry; and (3) a broader understanding

of how defendants’ interests in the specificity of class

definitions may vary from certification to settlement. The

Pursuant to Supreme Court Rule 37.6, amici certify that no

counsel for a party authored this brief in whole or in part, and no

person or entity other than amici made a monetary contribution to

fund the preparation or submission of this brief.

1

2

brief is meant solely to assist the Court in its consideration

of the issue presented and amici take no position on the

outcome of this particular case.

Amici submit this brief in their individual capacities as

scholars and teachers and not on behalf of The Presidents

and Fellows of Harvard College or New York University.

SUMMARY OF ARGUMENT

Amici make three points in this brief.

1. This Court has long held that a named plaintiff

must have Article III standing and that Rule 23 does not

enable the named plaintiff to borrow standing from the

other class members. Simon v. E. Ky. Welfare Rts. Org.,

426 U.S. 26, 40 n.20 (1976) (“That a suit may be a class

action . . . adds nothing to the question of standing . . . .”).

But, as a joinder device, Rule 23 also cannot destroy

standing. If the claims of some but not all members of a

proposed class meet the requirements of Article III, the

presence of non-justiciable claims within the class does not

destroy the justiciability of the live claims, cf. 28 U.S.C.

§ 2072(b) (procedural rules cannot “abridge, enlarge or

modify any substantive right”), and should not artificially

impede the capacity of those claims to proceed.

Courts are routinely faced with the proposed joinder

of live and non-justiciable claims or parties under other

joinder rules. A party may propose the joinder of live and

non-justiciable claims under Rule 18 and/or the joinder

of parties with and without standing under Rule 20.

In both situations, upon a proper motion (or on its own

initiative), the court dismisses the non-justiciable claims

and/or parties lacking standing – and the remaining joined

3

claims or parties proceed without them. Fed. R. Civ. P.

21 (“Misjoinder of parties is not a ground for dismissing

an action.”). Equity developed this approach to temper

the disproportionate consequences of misjoinder at the

common law – where misjoinder, regardless of the extent

of the defect or merit of the underlying claim, required

dismissal – and this approach has been embedded in the

Federal Rules of Civil Procedure since their inception in

1938.

This point supports the conclusion that the question

presented is a question of joinder, not justiciability, and

is best resolved using the many tools of Rule 23, not the

blunt force of Article III. The only reason the question

presented would speak to Article III itself is if standing

were analyzed on a class basis. But it is not: this Court’s

holdings have interpreted Rule 23(b)(3) classes to consist of

a bundle of individual claims, not a single classwide claim.

Wal-Mart Stores, Inc. v. Dukes, 564 U.S. 338, 363 (2011)

(describing a Rule 23(b)(3) class as consisting of “each

class member’s individualized claim for money”). As such,

the presence of the non-justiciable claims in the bundle

calls for their excision – as in the misjoinder situations

noted above – but does not lead to the conclusion that the

“class lacks standing.” That statement is inapposite to the

bundle of sticks conception of the class.

2. The Rule 23 issue that is raised is whether

identification and excision of the non-justiciable claims

is, in a given case, such an individualized undertaking

that it trumps the efficiency gains of proceeding in the

aggregate. This is another application of the predominance

and superiority prongs of Rule 23, no different in kind than

their application to affirmative defenses, counterclaims,

statutes of limitations, etc. See William B. Rubenstein,

4

2 Newberg and Rubenstein on Class Actions §§ 4:55 to

4:57 (6th ed. 2022) (hereinafter Newberg and Rubenstein

on Class Actions). The fact that a court would be applying

the predominance and superiority prongs to standing

does not transform that Rule 23 analysis into an Article

III question.

The Rule 23 analysis might merge into the Article

III analysis if, in all circumstances, excision of the nonjusticiable claims would be so onerous as to render common

issues non-predominant. Petitioner asserts that this will

“inevitably” be the case in the presence of “appreciable

numbers” of individualized inquiries. Pet’r Br. 48 (“Rule

23(b)(3) does not allow a court to certify a class where

individual questions predominate, which will inevitably

be the case when appreciable numbers of individualized

inquiries into standing are required.”) (emphasis added).

The lower courts have similarly used the quantity of

problematic claims within the class as a proxy for whether

common issues predominate.

But that proxy is imperfect: the issue for predominance

purposes is the ease of excision, not the number to be

excised. Often the class can be re-defined, and even a

large tranche of claims may be removable with a simple

edit. In other cases, identification and excision may be

mechanistically accomplished. The variations are many,

and the district courts are best suited to work out breaking

points in actual cases.

3. Petitioner frames the question presented in

terms of the – again – supposedly inevitable adverse

consequences to defendants when a court certifies a large

class before trial. Id. at 3 (“Once a class has been certified,

the next step is usually settlement, not trial. And that

5

likelihood becomes a near inevitability where a massive

class hazards colossal liability.”) (emphasis added). This

framing implies that overly large classes always harm

defendants, but in fact defendants may well prefer

overly large classes when class certification is sought in

conjunction with a welcomed settlement.

Defendants often take advantage of the class action

device as a litigation closure mechanism when facing

lawsuits in which liability is widespread and virtually

unavoidable – crashes, derailments, environmental spills.

The goal is to terminate all potential litigation, and

defendants accordingly support enormous settlement

classes encompassing significant numbers of potentially

non-justiciable claims. Indeed, it is not immediately obvious

whether plaintiffs seeking pre-settlement certification, or

defendants seeking a closure of their liability, are more

likely to propose bloated classes.

If the Court remains committed to the principle

that the class certification requirements are no different

at settlement than before, except for the issue of trial

manageability, Amchem Prods., Inc. v. Windsor, 521

U.S. 591, 620–21 (1997), a broad Article III ruling in this

matter would have negative consequences for defendants

seeking the safety of a class action settlement embodied

in a final judgment, as it would curtail the breadth of

releases permissible for that purpose.

***

In sum, the question presented is distinct from

related questions the Court addressed in prior cases.

In TransUnion LLC v. Ramirez, the Court held that,

“Every class member must have Article III standing

6

in order to recover individual damages,” 594 U.S. 413,

431 (2021), explaining that, “Article III does not give

federal courts the power to order relief to any uninjured

plaintiff, class action or not.” Id. (quoting Tyson Foods,

Inc. v. Bouaphakeo, 577 U.S. 442, 466 (2016) (Roberts,

C.J., concurring)). In so concluding, the Court also noted

that it was not addressing “the distinct question whether

every class member must demonstrate standing before

a court certifies a class.” Id. at 431 n.4. Both the holding

and footnote in TransUnion focused directly on Article

III, while the question presented in this case – “Whether

a federal court may certify a class action pursuant to

Federal Rule of Civil Procedure 23(b)(3) when some

members of the proposed class lack any Article III injury.”

– focuses directly on the joinder device. It accordingly

frames a question addressed by nearly a millennium of

joinder jurisprudence.

ARGUMENT

I.

Class Members Can Neither Borrow Standing From

One Another Nor Destroy One Another’s Standing.

The modern version of Rule 23 went into effect in

1966. Shortly thereafter, this Court held that, in general,

plaintiffs must have individual standing in order to bring

claims that might also redound to the benefit of a larger

group. Sierra Club v. Morton, 405 U.S. 727, 734–35 (1972)

(“[T]he ‘injury in fact’ test requires more than an injury

to a cognizable interest. It requires that the party seeking

review be himself among the injured.”). Two years later, in

the class context, the Court held that “if none of the named

plaintiffs purporting to represent a class establishes the

requisite of a case or controversy with the defendants, none

may seek relief on behalf of himself or any other member

7

of the class.” O’Shea v. Littleton, 414 U.S. 488, 494 (1974).

And the following year, the Court rounded out this trilogy

by holding that putative class representatives “must allege

and show that they personally have been injured, not that

injury has been suffered by other, unidentified members

of the class to which they belong and which they purport

to represent.” Warth v. Seldin, 422 U.S. 490, 502 (1975).

Summarizing this body of law nearly 50 years ago, the

Court wrote, “That a suit may be a class action . . . adds

nothing to the question of standing . . . .” Simon, 426 U.S.

at 40 n.20; see also Spokeo, Inc. v. Robins, 578 U.S. 330,

338 n.6 (2016). The law is therefore clear that a joinder

device – such as Rule 23 – cannot generate standing that

does not exist.

What has received less attention in the present debate,

but is equally pertinent, is that a joinder device also cannot

destroy a live claim. Federal courts deploy this principle in

applying other joinder rules (Rule 13 (counterclaims and

crossclaims), Rule 14 (third party claims), Rule 18 (claim

joinder), and Rule 20 (party joinder)). If a non-justiciable

claim or a party lacking standing is joined with a live

claim or party, the former is dismissed and the latter

proceeds without it; so too, a claim or party that would

destroy diversity jurisdiction is simply dismissed so as to

enable a case to proceed in federal court. This approach

is captured in Rule 21’s edict that “[m]isjoinder of parties

is not a ground for dismissing an action,” Fed. R. Civ. P.

21; rather, the Rule elegantly commands that the court

simply “drop” misjoined parties, id.

At common law, misjoinder was a “fatal defect”

authorizing dismissal, regardless of the strength of the

underlying claims or the extent of the misjoinder problem.

8

7 Charles Alan Wright, Arthur R. Miller, Mary Kay Kane,

& Howard M. Erichson, Federal Practice and Procedure

§ 1681 (3d ed. 2024) (“Except in cases involving joinder

of defendants in tort actions, misjoinder and nonjoinder

of parties were fatal defects in actions at common law; a

pleading that revealed a joinder defect was subject to attack

by general demurrer, motion in arrest of judgment, writ

of error, nonsuit, or plea in abatement.”); see also Henry

Greening & J. C. Perkins, Chitty’s Treatise on Pleading

and Parties to Actions, with a Second Volume Containing

Modern Precedents of Pleadings, and Practical Notes 228

(Springfield, G. & C. Merriam 1882) (“The consequences

of a misjoinder are more important than the circumstance

of a particular count being defective; for in the case of

misjoinder, however perfect the counts may respectively

be in themselves, the declaration will be bad on a general

demurrer, or in arrest of judgment, or upon error . . . .”)

(footnote omitted).

Capturing the gravity of the common law approach,

Professor Sunderland noted that, “The perils of misjoinder

were inherent risks which had to be patiently endured by

the people, like the perils of war and contagious disease.”

Edson R. Sunderland, Joinder of Actions, 18 Mich. L. Rev.

571, 575 (1920). Of course, “the severity of the penalties for

these mistakes naturally suggested the question, whether

they were not too heavy.” Id. at 573.

As was so often the case, equity came to the rescue.

It did so by developing rules that “generally allowed [a]

plaintiff to amend the complaint to correct a defect in

parties [such that] an action could proceed on its merits

despite an initial misjoinder or nonjoinder whenever the

error could be corrected without adversely affecting the

9

parties to the action.” Wright, Miller, Kane, & Erichson,

supra, § 1681 (citing Fed. R. Eq. 43–44).

The party joinder issue in group litigation generally

concerned nonjoinder given that a decree might impact

the interests of missing parties. See generally Stephen C.

Yeazell, From Medieval Group Litigation to the Modern

Class Action (1987). The recurring question was whether

equity could proceed in the absence of these parties,

with related inquiries into whether missing parties were

“necessary” or “indispensable.” Geoffrey C. Hazard,

Jr., Indispensable Party: The Historical Original of a

Procedural Phantom, 61 Colum. L. Rev. 1254, 1254–55

(1961). These concerns haunted equity for centuries, but

they were effectively ushered offstage for money damage

class actions in 1966, when Rule 23(b)(3) became an

opt-out, rather than an opt-in, mechanism. That change

transformed problems of nonjoinder into questions of

misjoinder, with equity’s apprehensions about crafting

careful decrees giving way to contemporary concerns

about drafting careful class definitions. Thus, although

the question presented in this matter arises in the context

of group litigation, its over-inclusion concern finds more

resonance in the history of misjoinder at common law than

in the history of group litigation in the equity courts.

With the merger of law and equity in 1938, all of these

issues found new homes in the federal rules: indispensable

parties and group litigation in Rules 19 and 23 and equity’s

approach to misjoinder in Rule 21. See Fed. R. Civ. P. 21

advisory committee’s note (“See also [former] Equity

Rules 43 (Defect of Parties–Resisting Objection) and 44

(Defect of Parties–Tardy Objection)”); Wright, Miller,

Kane, & Erichson, supra, § 1681 (“Federal Rule of Civil

10

Procedure 21 was derived from the federal equity rules

and the English rules of practice existing at the time the

Federal Rules of Civil Procedure were adopted.”).

Rule 21’s goal was precisely to avoid inflexible and

formalistic approaches to party joinder. Soc’y of Eur. Stage

Authors & Composers v. WCAU Broad. Co., 1 F.R.D. 264,

266 (E.D. Pa. 1940) (“Rules 17, 19, 20 and 21, relating to

Parties, evidence the general purpose of the new Rules to

eliminate the old restrictive and inflexible rules of joinder

designed for a day when formalism was the vogue and to

allow joinder of interested parties liberally to the end

that an unnecessary multiplicity of actions thus might be

avoided.”). “By providing for the dropping and adding of

parties on terms that are just, Rule 21 furthers the policy

of the federal rules to continue and to determine an action

on its merits whenever that can be done without prejudice

to the parties.” Wright, Miller, Kane, & Erichson, supra,

§ 1681.

The letter of Rule 21 is applicable to class actions,

id. at § 1682 (“The scope of application of Federal Rule

of Civil Procedure 21 is extremely broad and covers any

civil action in the federal courts.”), but the Rule itself is

rarely referenced in this context, for its spirit is captured

directly by Rule 23(c)(1)(C). That provision states:

An order that grants or denies class certification

may be altered or amended before final

judgment.

Fed. R. Civ. P. 23(c)(1)(C). As such, it is a direct descendent

of the English equity courts’ approach to misjoinder:

11

Any application to add or strike out or substitute

a plaintiff or defendant may be made to the

court or a judge at any time before trial by

motion or summons, or at the trial of the action

in a summary manner.

Fed. R. Eq. 43 (1912) (repealed 1938), reprinted in James

Love Hopkins, The New Federal Equity Rules 248 (8th

ed. 1933) (editor’s note quoting Order XVI, Rule 12).

In fact, Rule 23 is even more liberal than equity

had been: [1] it does not require an “application” for the

court to alter the class, and [2] it expands the time frame

for correcting misjoinder all the way to final judgment.

What this lineage – and the clear texts of Rule 21 and

Rule 23 – teaches is that a court may pare down a class

that is proposed for certification, or even one that has

been certified, so as to “drop” any class members who

lack standing should non-justiciable claims find their way

into the mix. See 3 Newberg and Rubenstein on Class

Actions § 7:27 (“[C]ourts in every circuit have held, when

a class definition is not acceptable, judicial discretion can

be utilized to save the lawsuit from dismissal. Indeed,

several circuits have held that a court should alter the

class definition in lieu of rejecting class certification, if

possible. This discretion extends to creating sub-classes,

as well as to modifying an approved class.”) (footnotes

omitted). In short, neither dismissal, nor rejection of class

certification, are proper consequences of misjoinder – nor

have they been since before the Civil War.

That conclusion is not altered by the fact that the

joinder problem in this matter is one of justiciability.

This Court itself has employed Rule 21 to fix a standing

problem – through substitution of a real party in interest

12

for its agent – in a case pending before it. Mullaney v.

Anderson, 342 U.S. 415, 417 (1952) (Frankfurter, J.). The

Court did so because “[t]o dismiss the present petition and

require the new plaintiffs to start over in the District Court

would entail needless waste and runs counter to effective

judicial administration.” Id. The Court noted that “Rule 21

will rarely come into play at this stage of a litigation,” id.,

but lower federal courts regularly employ Rule 21 to drop

joined parties who lack standing, see, e.g., Charlatan v.

Clayton Cnty. Gov’t, No. 19-CV-00199, 2020 WL 9598956,

at *1 (M.D. Ga. Nov. 23, 2020) (recommending that plaintiff

who “failed to establish that she has standing to prosecute

this action” be dropped), report and recommendation

adopted, No. 19-CV-00199, 2021 WL 1976631 (M.D. Ga.

Apr. 20, 2021); Uniloc 2017, LLC v. Google LLC, No. 18-cv00496, 2019 WL 6006228, at *1 (E.D. Tex. Aug. 16, 2019)

(same), report and recommendation adopted, No. 18-cv00496, 2019 WL 6002210 (E.D. Tex. Sept. 10, 2019); Boyd

v. Seterus, Inc., No. CV-17-76-GW, 2017 WL 8110070, at *3

(C.D. Cal. Mar. 30, 2017) (adopting tentative ruling that

plaintiff who lacked standing would be dismissed under

Rule 21); Alexander v. C.R. Bard, Inc., No. 12-cv-5187, 2014

WL 12602871, at *8 (N.D. Tex. Feb. 26, 2014) (employing

Rule 21 to substitute real party in interest for plaintiff who

lacked standing rather than granting summary judgment).

Rule 21 performs the same function in the area of

subject matter jurisdiction, enabling a court to reject

claims or parties that would destroy diversity without

requiring dismissal of the entire action. Wright, Miller,

Kane, & Erichson, supra, § 1685 (“Courts frequently

employ Federal Rule of Civil Procedure 21 to preserve

diversity jurisdiction over a case by dropping a nondiverse

party if the party’s presence in the action is not required

under Federal Rule of Civil Procedure 19.”).

13

Rule 23(c)(1)(C) enables federal courts to approach

standing-related misjoinder in class actions in precisely

the same manner, “dropping” the non-justiciable claims of

absent class members who lack standing, while permitting

the justiciable claims to proceed in the class form assuming

the other requirements of certification are met. Claims

found to be nonjusticiable as the case progresses can also

be dropped after certification, as the assessment of both

justiciability and the contours of the class are dynamic,

not static, processes.

The federal courts’ approach to misjoinder accordingly

belies the Petitioner’s argument that, “ARTICLE III

PROHIBITS CERTIFICATION OF A PROPOSED

RULE 23(B)(3) CLASS THAT CONTAINS UNINJURED

MEMBERS.” Pet’r Br. 15. The only way that statement

would make sense would be if standing in a class suit

were dispensed in bulk, rather than class member by

class member, such that the presence of a single nonjusticiable claim spoiled the whole bunch. But this

Court has repeatedly held the opposite, noting both that

“standing is not dispensed in gross,” Lewis v. Casey, 518

U.S. 343, 358 n.6 (1996), and that Rule 23(b)(3) claims are

“individualized monetary claims,” Dukes, 564 U.S. at 362.

It follows that there is no such thing as “class standing,”

only the standing of each individual claimant within the

class. Accordingly, a court can survey the Rule 23(b)

(3) class just as it would a multi-party joinder situation

under Rule 21, identifying the justiciability of claims and

“dropping” the non-justiciable ones from the class.

In sum, given that joinder rules cannot create or

destroy standing, a class action court can no more assert

jurisdiction over non-justiciable claims than a non-class

14

court can. But the remedy for the misjoinder of such claims

and parties is, as in the non-class context, the dismissal

of those claims and/or parties, not a refusal to let the live

claims proceed. A bloated class definition should neither

cause an in terrorem effect on defendants nor occasion for

plaintiffs the death knell of an otherwise viable class suit.

Microsoft Corp. v. Baker, 582 U.S. 23, 29 (2017) (noting

relationship between the death knell and in terrorem

problems).

To permit trial courts to work out the Article

III implications of class definitions using the tools of

certification, and Rule 23(c)(1)(C) thereafter, is consistent

with the Court’s prior holdings. Amchem held that

capturing the proper contours of a class may not be a single

fixed decision, stating that “when a case is litigated, [the

trial court can] adjust the class [definition], informed by

the proceedings as they unfold.” Amchem, 521 U.S. at 620

(citing Fed. R. Civ. P. 23(c)–(d)). In turn, TransUnion and

Tyson safeguard Article III at judgment. Together, the

Court’s precedents support the conclusion that judgment

is the appropriate time to require final assessments of

standing; while some such assessments may be clear and

executable at certification, not all standing questions

should be prematurely force-fit into the class certification

analysis, when much may still remain unknown about the

merits of each stick within the bundle.

II. The Predominance Issue Is Not One of Quantity

but Ease of Removal.

Once the standing issue is properly viewed as a

problem of misjoinder, with the remedy being to drop the

misjoined, the issue a court faces is whether the process of

15

removing non-justiciable claims/class members is feasible

within the mechanics of Rule 23. If the excision of the bad

claims/parties will entail myriad individual assessments,

non-common issues will predominate, and the efficiency

gains of the class suit will be lost. Fed. R. Civ. P. 23(b)(3)

(demanding that common issues predominate and that

the class mechanism be a superior means of adjudication).

Petitioner asserts that the predominance inquiry

should turn on number, arguing that if an “appreciable

number” of putative class members plausibly lack standing,

the quantity of individual inquiries will necessarily

render common issues non-predominant. Pet’r Br. 37–48.

Lower court decisions have similarly used the number

of plausible class members lacking antitrust injury as

a proxy for when common issues will not predominate in

that context. See, e.g., In re Rail Freight Fuel Surcharge

Antitrust Litig., 934 F.3d 619, 627 (D.C. Cir. 2019)

(finding that “the need . . . for at least 2,037 individual

determinations of [antitrust] injury” for the uninjured

class members justifies “denying class certification on the

ground that common issues do not predominate”); In re

Asacol Antitrust Litig., 907 F.3d 42, 53–54 (1st Cir. 2018)

(reversing the district court’s class certification in which

“thousands . . . suffered no [antitrust] injury,” as “[t]he

need to identify those individuals will predominate”); In

re Nexium Antitrust Litig., 777 F.3d 9, 21 (1st Cir. 2015)

(“We do not think the need for individual determinations

or inquiry [of antitrust injury] for a de minimus number of

uninjured members at later stages of the litigation defeats

class certification.”). 2

Petitioner relies on some of these antitrust injury cases in

its predominance argument about Article III injury. Pet’r Br. 41

(citing Asacol, 907 F.3d 42, and Rail Freight, 934 F.3d 619). The

predominance question may be similar across the domains, but

2

16

But this presumption that the number of uninjured

class members determines the predominance question

is not quite right. The question for predominance is not

quantity but the method for excising the uninjured. Even

if many putative class members have non-justiciable

claims, so long as the method of removing them from the

class is straightforward, that excision will be mechanical

and common issues may still predominate. There are

numerous mechanisms for excision: the court or class

proponents could redefine the class to encompass only live

claims; the inquiry that would be needed to separate the

wheat from the chaff could be so mechanistic that even

applying it to a large class would not be inefficient; or, as

some lower courts presume, the quantity of non-live claims

might be so small that even individualized inquiries would

not overwhelm the efficiencies of the class suit.

This means that if the Court were to adopt the paring

approach of Rule 21, it should direct lower courts to

focus on whether the process of excluding non-justiciable

claims will overwhelm the efficiencies of proceeding in the

aggregate – and not to use the sheer number of plausibly

non-justiciable claims as a proxy for that consideration.

See In re Visa Check/MasterMoney Antitrust Litig., 280

F.3d 124, 140–41 (2d Cir. 2001) (Sotomayor, J.) (holding

that “failure to certify an action under Rule 23(b)(3) on the

sole ground that it would be unmanageable is disfavored

and should be the exception rather than the rule” and

identifying “a number of management tools available to

a district court to address any individualized damages

issues that might arise in a class action, including: (1)

the issues are not fully transposable since Article III injury is a

jurisdictional question, while antitrust injury is a merits inquiry.

17

bifurcating liability and damage trials with the same

or different juries; (2) appointing a magistrate judge

or special master to preside over individual damages

proceedings; (3) decertifying the class after the liability

trial and providing notice to class members concerning

how they may proceed to prove damages; (4) creating

subclasses; or (5) altering or amending the class”) (cleaned

up) (quoting In re S. Cent. States Bakery Prods. Antitrust

Litig., 86 F.R.D. 407, 423 (M.D. La. 1980)).

III. Defendants’ Interests Are More Mixed Than

Petitioner Portrays.

Petitioner proposes that certifying a class encompassing

both live and non-justiciable claims artificially bloats the

class size, pressuring settlements out of proportion to

harm. Pet’r Br. 3, 32-33. Although that portrayal of these

dynamics may or may not be accurate – scholars have

challenged the argument, see, e.g., Charles Silver, “We’re

Scared to Death”: Class Certification and Blackmail, 78

N.Y.U. L. Rev. 1357, 1385–1429 (2003) – the proposition is

focused on contested class certification motions decided

before trial.

When liability is more likely – crashes, derailments,

environmental spills, diesel emissions fraud – defendants

often embrace the class mechanism because (short of

bankruptcy) only a class action judgment can provide near

total closure. See D. Theodore Rave, Closure Provisions

in MDL Settlements, 85 Fordham L. Rev. 2175, 2187–88

(2017) (“A class action settlement increases closure by

shifting from an opt-in model to an opt-out model. Instead

of individual claimants needing to affirmatively sign on to

the settlement, all claimants within the class definition

18

are automatically bound by the settlement unless they

opt out.”) (emphasis added). But, in seeking that closure,

frequently characterized as “global peace,” Reed Elsevier,

Inc. v. Muchnick, 559 U.S. 154, 159 (2010) (noting goal of

class action settlement was “to achieve a global peace in

the publishing industry”) (quoting In re Literary Works

in Elec. Databases Copyright Litig., 509 F.3d 116, 119

(2d Cir. 2007)), settling defendants have an interest in

maximizing the breadth of the class, lest future litigation

seep through the seams of the settlement.

The Federal Judicial Center, in advising federal

judges what to look for when reviewing a proposed class

action settlement, goes so far as to state that, “A natural

impulse on the part of settling parties is to attempt

to expand the class and release claims of those on the

periphery of the class . . . .” Barbara J. Rothstein &

Thomas E. Willging, Managing Class Action Litigation:

A Pocket Guide for Judges 22 (3d ed. 2010) (emphasis

added). Similarly, the U.S. District Court for the

Northern District of California’s Procedural Guidance

for Class Action Settlements (an influential guidepost

for judges throughout the country) directs litigants as

to what information to provide in conjunction with a

motion seeking preliminary approval of a settlement;

the first such direction requires the motion to identify

“[a]ny differences between the settlement class and the

class proposed in the operative complaint (or, if a class

has been certified, the certified class) and an explanation

as to why the differences are appropriate.” Procedural

Guidance for Class Action Settlements, U.S. Dist. Ct.,

N. Dist. of Cal. (last modified Sept. 5, 2024), https://www.

cand.uscourts.gov/forms/procedural-guidance-for-classaction-settlements/.

19

In their “natural” expansion toward “global” peace,

settlement classes may exceed the bounds of actual harm.

In the cases arising out of the 2010 BP oil spill in the

Gulf of Mexico, for instance, the defendants negotiated

a settlement class definition that encompassed all of the

citizens of three states and many of the citizens of two

other states – or nearly one in five Americans – if impacted

by the spill. In re: Oil Spill by the Oil Rig “Deepwater

Horizon” in the Gulf of Mexico, on April 20, 2010, 910

F. Supp. 2d 891, 965–68 (E.D. La. 2012) (appendix B),

aff’d sub nom. In re Deepwater Horizon, 739 F.3d 790

(5th Cir. 2014). Not surprisingly, questions subsequently

arose about whether the claims administrator was paying

out monies to uninjured parties, see In re Deepwater

Horizon, 744 F.3d 370, 373 (5th Cir. 2014), with the Fifth

Circuit chiding the defendants in concluding that, “There

is nothing fundamentally unreasonable about what BP

accepted but now wishes it had not,” id. at 377.

This Court itself recognized the “natural” expansion

of settlement classes 15 years before the BP settlement

– and warned courts to guard against this problem.

Specifically, in holding that that the requirements for

certifying a class in conjunction with a settlement are

the same as the requirements of pre-settlement class

certification (except manageability). Amchem, 521 U.S.

at 620–21, the Court focused on definitional overbreadth,

writing:

Confronted with a request for settlement-only

class certification, a district court need not

inquire whether the case, if tried, would present

intractable management problems, see Fed.

Rule Civ. Proc. 23(b)(3)(D), for the proposal is

that there be no trial. But other specifications of

20

the Rule—those designed to protect absentees

by blocking unwar ranted or overbroad

class definitions—demand undiluted, even

heightened, attention in the settlement context.

Id. at 620 (emphasis added).

The Court expressed concern about overbroad

settlement class definitions because, as noted above, “a

court asked to certify a settlement class will lack the

opportunity, present when a case is litigated, to adjust

the class, informed by the proceedings as they unfold.” Id.

(citing Fed. R. Civ. P. 23(c)–(d)); see also In re Hyundai

& Kia Fuel Econ. Litig., 926 F.3d 539, 558 (9th Cir. 2019)

(“The adversarial nature of a trial ensures that class

definitions will be tested and allows the district court

‘to adjust the class, informed by the proceedings as they

unfold.’ A settlement lacks these safeguards.”) (citation

omitted) (quoting Amchem, 521 U.S. at 620).

If the Court were to hold that classes cannot, as a

constitutional matter, be certified if they contain nonjusticiable claims – and if the lower courts actually

followed the Amchem principle3 – settlement classes would

Morris A. Ratner, Class Conflicts, 92 Wash. L. Rev. 785, 860

(2017) (“If judges are confident they have helped to achieve a just

class settlement that they view as their only viable endgame, and

if a strict reading of Amchem disrupts that settlement, odds are

that judges will read the strictness out of the decision. And so they

have.”); cf. 2 Newberg and Rubenstein on Class Actions § 4:63 (“[M]

any courts have held that individualized issues may bar certification

for adjudication because of predominance-related manageability

concerns but that these same problems do not bar certification for

settlement. Courts therefore regularly certify settlement classes

that might not have been certifiable for trial purposes because of

manageability concerns.”) (footnote omitted).

3

21

have to be narrower than is common, and the closure that

the defendants would obtain would be more modest than

their desires at that point.

Amici are indifferent to these dynamics, and perhaps

the Court should be as well. But Petitioner presents its

case in terms of fairness to defendants. When the full

range of situations and dynamics in which overly broad

classes might be proposed and approved are brought

into focus, however, it becomes far less clear that a broad

Article III–based decision would inevitably be defendantfriendly.

CONCLUSION

The Court’s decision in this matter may benefit from

consideration of (1) the history underlying the joinderbased nature of the question presented; (2) the fact that

ease, rather than quantity per se, is the proper focus of

the predominance inquiry; and (3) the shifting interests of

defendants with respect to certification of broad classes.

Respectfully submitted,

William B. Rubenstein

Counsel of Record

1545 Massachusetts Avenue

Cambridge, MA 02138

(617) 496-7320

rubenstein@law.harvard.edu

Counsel for Amici Curiae

March 12, 2025