Hain Celestial Group, Inc. v. Palmquist

A
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T H E S U P R E M E C O U R T
February 24, 2026
REBECCA A. WOMELDORF
reporter of decisions
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421
Syllabus
HAIN CELESTIAL GROUP, INC., et al. v.
P
ALMQUIST, individually and as next
friend of E. P., a minor, et al.
certiorari to the united states court of appeals for
the fth circuit
No. 24–724. Argued November 4, 2025—Decided February 24, 2026
Respondents Sarah and Grant Palmquist fed their child E. P. baby food
that was made by petitioner Hain Celestial Group, Inc., and that they
purchased from petitioner Whole Foods Market, Inc. When E. P. was
2½ years old, he began exhibiting serious developmental disorders and
was diagnosed with a range of physical and mental conditions that some
doctors attributed to heavy-metal poisoning. In 2021, a subcommittee
of the U. S. House of Representatives released a staff report fnding that
certain baby foods, including Hain's, contained elevated levels of toxic
heavy metals. Following the report's release, the Palmquists sued both
Hain and Whole Foods in Texas state court, alleging state-law product
liability and negligence claims against Hain, and state-law breach-of-
warranty and negligence claims against Whole Foods. Hain, a Dela-
ware corporation with a principal place of business in New York, re-
moved the case to federal court based on diversity of citizenship, but
confronted a problem: Federal courts may exercise diversity jurisdiction
only when no adverse party is from the same State, but Whole Foods
and the Palmquists are all Texas citizens. As a result, the District
Court lacked jurisdiction as the case stood upon removal. Hain sought
to cure this problem by arguing in its notice of removal that Whole
Foods had been improperly joined in the lawsuit and should be dis-
missed, which would have established complete diversity between Hain
and the Palmquists. The District Court agreed with Hain, dismissed
Whole Foods, and denied the Palmquists' motion to remand. The case
then went to trial against Hain alone in federal court. The District
Court granted Hain's motion for judgment as a matter of law on all
claims, explaining that the Palmquists had failed to present suffcient
evidence to prove causation. On appeal, the Fifth Circuit reversed the
District Court's improper-joinder decision and dismissal of Whole Foods.
Because Whole Foods had been improperly dismissed, the Fifth Circuit
concluded that the District Court lacked diversity jurisdiction, that the
District Court's judgment had to be vacated, and that the case had to
be remanded to state court. This Court granted certiorari to resolve a

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422 HAIN
CELESTIAL GROUP, INC. v. PALMQUIST
Syllabus
divide among the Courts of Appeals on whether vacatur is required in
these
circumstances.
Held: Because the District Court's erroneous dismissal of Whole Foods did
not cure the jurisdictional defect that existed when this case was re-
moved to federal court, the Fifth Circuit correctly vacated the judgment
in Hain's favor. Pp. 427–434.
(a) Federal courts are courts of limited jurisdiction, and a federal
court of appeals must “satisfy itself not only of its own jurisdiction, but
also of that of the lower courts in a cause under review.” Mitchell v.
Maurer, 293 U. S. 237, 244. In most cases, federal appellate courts as-
sess the district court's jurisdiction based on “the state of facts that
existed at the time of fling.” Grupo Datafux v. Atlas Global Group,
L. P., 541 U. S. 567, 571. If the court of appeals concludes that the
district court lacked jurisdiction over the case when it was fled in or
removed to federal court, then the court of appeals typically must vacate
any judgment on the merits.
One exception to this general rule is relevant here: If a district court
cures a jurisdictional defect before fnal judgment, then the court of
appeals is not required to vacate that judgment even if, at some earlier
point in the case, the district court lacked jurisdiction. The Court dis-
cussed this exception in Caterpillar Inc. v. Lewis, 519 U. S. 61, in which
the nondiverse defendant was fully dismissed with all of the parties'
consent through a partial fnal judgment under Federal Rule of Civil
Procedure 54(b), leaving behind a completely diverse set of parties be-
fore trial commenced. In those circumstances, the Court held that the
jurisdictional defect had been cured and the verdict could stand despite
the District Court's earlier “statutory misstep” in denying the motion to
remand. Id., at 73. On the other hand, the Court stated, had the juris-
dictional defect not been cured and instead “lingered through judgment,”
then vacatur would have been required. Id., at 76–77. Pp. 428–430.
(b) The core dispute in this case is whether Whole Foods's erroneous
dismissal before fnal judgment cured the jurisdictional defect that ex-
isted at the time of removal. It did not. The District Court's dismissal
of Whole Foods as improperly joined was both erroneous and “[i]nterloc-
utory,” meaning it did “not dispose of the whole case” and “merge[d]
into the fnal judgment” for “revie[w] on appeal.” Dupree v. Younger,
598 U. S. 729, 734, 735. When the Fifth Circuit reversed the District
Court's error, it restored Whole Foods to the case and thus destroyed
complete diversity. As a result, the jurisdictional defect “lingered
through judgment” uncured and the judgment “must be vacated.” Cat-
erpillar, 519 U. S., at 77.

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423
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Hain argues that the correctness of the District Court's dismissal is
irrele
vant because the parties were completely diverse by the time of
fnal judgment, but the Court has never held that a district court can
create jurisdiction through its own mistakes. A rule to the contrary
would permit courts to enlarge their jurisdiction beyond the limits Con-
gress imposed. Hain also appeals to effciency, arguing that it would
be wasteful to send this case back to state court for a new trial. The
“considerations of fnality, effciency, and economy” recognized in Cater-
pillar, 519 U. S., at 75, however, were relevant only to excusing noncom-
pliance with the removal statute's requirement of complete diversity at
the time of removal after a jurisdictional defect has been properly and
fnally cured. As to the jurisdictional requirement itself, Caterpillar
held that an uncured jurisdictional defect means that “the judgment
must be vacated.” Id., at 76–77. Pp. 430–432.
(c) Finally, Hain argues that Whole Foods should now be dismissed
under Federal Rule of Civil Procedure 21, which permits a federal court
to “add or drop a party” “on just terms.” In Newman-Green, Inc. v.
Al fonzo-Larrain, 490 U. S. 826, 833, 837–838, the Court held that courts
may use Rule 21 “to dismiss a dispensable nondiverse party” in appro-
priate circumstances, but must “carefully consider whether the dis-
missal . . . will prejudice any of the parties in the litigation.” This case
is unlike Newman-Green, in which the plaintiff sought the dismissal,
because here a defendant is seeking dismissal of another, nondiverse
defendant. The identity of the party asking for the dismissal is impor-
tant because “[t]he plaintiff is `the master of the complaint,' ” and gener-
ally has the right to choose whether to proceed in federal or state court.
Royal Canin U. S. A., Inc. v. Wullschleger, 604 U. S. 22, 35. Hain's pro-
posed use of Rule 21 would force the Palmquists to litigate this case in
federal court against their wishes and despite their right to control the
forum for this case. See Atlantic Marine Constr. Co. v. United States
Dist. Court for Western Dist. of Tex., 571 U. S. 49, 63. The Palmquists
exercised their right to choose a state forum by purposefully and prop-
erly joining a nondiverse defendant against whom they could not pro-
ceed in federal court, and diligently asserted that right by promptly
moving to remand the case to state court. Rule 21 does not permit a
court or a defendant to override their choice in these circumstances.
Pp. 432–433.
103 F. 4th 294, affrmed and remanded.
Sotomayor, J., delivered the opinion for a unanimous Court. Thomas,
J., fled a concurring opinion, post, p. 434.

424 HAIN
CELESTIAL GROUP, INC. v. PALMQUIST
Opinion of the Court
Sarah E. Harrington argued the cause for petitioners.
W
ith her on the briefs were Paul W. Schmidt, Michael X.
Imbroscio, Abby C. Wright, Nicole M. Antoine, Matthew C.
Quallen, Bradley E. Chambers, Kristine L. Roberts, Brian
M. Ballay, and Alexandra B. Rychlak.
Russell S. Post argued the cause for respondents. With
him on the brief were Owen J. McGovern and David C.
Frederick.*
Justice Sotomayor delivered the opinion of the Court.
Federal courts are courts of limited jurisdiction and gener-
ally can resolve only the cases that Congress grants them
power to hear. One class of cases over which Congress has
given federal courts jurisdiction is “diversity” cases between
“citizens of different States.” 28 U. S. C. § 1332(a).
If a federal court of appeals fnds that a district court
lacked jurisdiction over a case (for example, because the par-
ties turned out not to be from different States), then the
district court's judgment on the merits must be vacated. A
district court's judgment can stand, however, if the district
court “cured” the jurisdictional defect before entering fnal
judgment, such as by properly dismissing a nondiverse party
from the case.
This case asks whether a district court's erroneous dis-
missal of a nondiverse party before fnal judgment can cure
a jurisdictional defect that existed when the case was re-
moved to federal court. The Fifth Circuit held that it can-
*Briefs of amici curiae urging reversal were fled for the National Asso-
ciation of Manufacturers et al. by Jaime A. Santos, Rohiniyurie Tashima,
Jennifer B. Dickey, and Erica Klenicki; for the Product Liability Advi-
sory Council, Inc., by Nicole Saharsky and Minh Nguyen-Dang; and for
the Washington Legal Foundation by Cory L. Andrews and Zac Morgan.
Lawrence S. Ebner fled a brief for the Atlantic Legal Foundation as ami-
cus curiae urging vacatur and remand.
Briefs of amici curiae urging affrmance were fled for the American
Association for Justice by Deepak Gupta and Jonathan E. Taylor; and for
Civil Procedure Professors by David Freeman Engstrom, pro se.
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Opinion of the Court
not, and this Court agrees. In these circumstances, the dis-
tr
ict court's fnal judgment must be vacated for lack of
jurisdiction.
I
Respondents Sarah Palmquist and Grant Palmquist have
a young son, E. P., who was born in 2014. For the frst two
years of E. P.'s life, the Palmquists fed him baby food that
was made by petitioner Hain Celestial Group, Inc., and that
they purchased from petitioner Whole Foods Market, Inc.
At frst, E. P.'s development progressed ordinarily, and he
was a healthy child. Things changed when E. P. was 2½
years old. He began exhibiting serious developmental dis-
orders and was diagnosed with a range of physical and men-
tal conditions. After identifying high levels of arsenic, lead,
and mercury in E. P.'s blood tests, some doctors attributed
these conditions to heavy-metal poisoning. In 2021, years
after E. P.'s diagnosis, a subcommittee of the U. S. House of
Representatives Committee on Oversight and Reform re-
leased a staff report fnding that certain baby foods, includ-
ing Hain's, contained elevated levels of toxic heavy metals.
See Staff Report, Subcommittee on Economic and Consumer
Policy, Baby Foods Are Tainted With Dangerous Levels of
Arsenic, Lead, Cadmium, and Mercury 2–4 (Feb. 4, 2021).
Following the report's release, the Palmquists sued both
Hain and Whole Foods in Texas state court. As to Hain, the
Palmquists alleged state-law product liability and negligence
claims. As to Whole Foods, the Palmquists alleged state-
law breach of warranty and negligence claims based on
Whole Foods's alleged misrepresentation of Hain's products
as safe for consumption.
Hain removed the case to federal court based on the par-
ties' diversity of citizenship. At the time of removal, how-
ever, Hain confronted a problem. Generally, 28 U. S. C.
§ 1332(a) allows federal courts to exercise jurisdiction only
when the parties are completely diverse, which means that
no adverse party is from the same State, and the amount in
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426 HAIN
CELESTIAL GROUP, INC. v. PALMQUIST
Opinion of the Court
controversy exceeds $75,000. Lincoln Property Co. v.
Roch
e, 546 U. S. 81, 89 (2005). As the case stood upon re-
moval, though, this requirement was not met. The Palm-
quists were Texas citizens. Hain was a Delaware corpora-
tion with a principal place of business in New York, and so
was both a Delaware and New York citizen. Whole Foods,
however, was headquartered in Texas and so was, like the
Palmquists, a Texas citizen. Because Whole Foods and the
Palmquists were all Texas citizens, the parties were not com-
pletely diverse.
Hain nevertheless argued in its notice of removal that re-
moval was proper because Whole Foods had been improperly
joined and should be dismissed, which would leave only par-
ties who were completely diverse in federal court. The
Palmquists disagreed, argued that Whole Foods was prop-
erly joined, and moved to remand the case to state court
given the lack of diversity jurisdiction.
1
The District Court sided with Hain. Under Fifth Circuit
precedent, which was not disputed here, a defendant is im-
properly joined if the plaintiff fails to “state a claim for relief
that is facially plausible” against the defendant. 103 F. 4th
294, 304 (2024); see Smallwood v. Illinois Central R. Co., 385
F. 3d 568, 573 (2004) (en banc). Applying that test, the Dis-
trict Court concluded that the Palmquists had not alleged a
plausible claim against Whole Foods. It thus dismissed
Whole Foods and denied the Palmquists' motion to remand.
The Palmquists then went to trial against Hain in federal
court. After the Palmquists rested their case, Hain moved
for judgment as a matter of law on all claims. The District
Court granted that motion in full, explaining that the Palm-
quists had failed to present suffcient evidence to the jury to
prove that “the ingestion of heavy metals can cause the
array of symptoms that [E. P.] suffers from, much less any
1
Improper joinder is also often referred to as “fraudulent joinder.” Be-
cause there are no allegations of fraud by the Palmquists in this case, the
Court uses the term “improper joinder.”

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evidence of at what level those metals would have to be in-
gested
to bring about those symptoms.” 103 F. 4th, at 300.
The Palmquists appealed that judgment along with the Dis-
trict Court's improper-joinder decision that had dismissed
Whole Foods.
The Fifth Circuit reversed the improper-joinder decision
and vacated the District Court's judgment. The Court of
Appeals held that Whole Foods was properly joined because
the Palmquists had plausibly alleged that Whole Foods had
violated state law by misrepresenting Hain's products as
safe. Given that Whole Foods had been erroneously dis-
missed, the action was not diverse. The Court of Appeals
then concluded that the District Court lacked jurisdiction
and that the judgment in Hain's favor had to be vacated.
The Fifth Circuit denied en banc review.
Hain and Whole Foods fled a timely petition for certiorari
seeking review of the Fifth Circuit's holding that the District
Court's judgment must be vacated. One other Court of Ap-
peals has held that vacatur is not required in these circum-
stances, while another agrees with the Fifth Circuit and has
held that it is.
2
The Court granted certiorari to resolve the
divide among the Courts of Appeals. See 604 U. S. 1267
(2025).
II
It is important to emphasize at the outset “two `givens' in
this case.” Caterpillar Inc. v. Lewis, 519 U. S. 61, 70 (1996).
First, no party asks this Court to revisit the Fifth Circuit's
holding that the District Court's improper-joinder decision
was incorrect and that Whole Foods should not have been
dismissed. See Brief for Petitioners 7, n. 1. Second, no
party disputes that, had the District Court performed the
joinder analysis correctly when the case was initially re-
2
Compare Junk v. Terminix Int'l Co., 628 F. 3d 439, 447, 450–451 (CA8
2010), with Henderson v. Washington Nat. Ins. Co., 454 F. 3d 1278, 1284–
1285 (CA11 2006).

428 HAIN
CELESTIAL GROUP, INC. v. PALMQUIST
Opinion of the Court
moved, it would have lacked jurisdiction and would have
been
required to remand the case to state court. See 28
U. S. C. §§ 1332(a), 1447(c). What remains for this Court to
decide is whether the District Court, having erroneously dis-
missed Whole Foods, had jurisdiction to enter a fnal judg-
ment as to Hain. It did not.
A
Federal courts “are all of limited jurisdiction, and their
proceedings are erroneous, if the jurisdiction be not shown
upon them.” Kempe's Lessee v. Kennedy, 5 Cranch 173, 185
(1809) (Marshall, C. J.). Because of this limitation on federal
courts' authority, a federal court of appeals must “satisfy it-
self not only of its own jurisdiction, but also of that of the
lower courts in a cause under review.” Mitchell v. Maurer,
293 U. S. 237, 244 (1934). In most cases, federal appellate
courts assess the district court's jurisdiction based on “the
state of facts that existed at the time of fling.” Grupo Da-
tafux v. Atlas Global Group, L. P., 541 U. S. 567, 571 (2004).
If the court of appeals concludes that the district court
lacked jurisdiction over the case when it was fled in or re-
moved to federal court, then the court of appeals typically
must vacate any judgment on the merits. See Williams v.
Zbaraz, 448 U. S. 358, 368 (1980); American Fire & Casualty
Co. v. Finn, 341 U. S. 6, 17–18 (1951).
There is, however, one exception to the general rule rele-
vant to this case. If a district court “cures” a jurisdictional
defect prior to fnal judgment, then the court of appeals is
not required to vacate that judgment even if, at some earlier
point in the case, the district court lacked jurisdiction.
The Court discussed this exception in Caterpillar Inc. v.
Lewis, 519 U. S. 61. In Caterpillar, Lewis was a citizen of
Kentucky who brought a product-liability suit in state court
against Caterpillar, a Delaware- and Illinois-based equip-
ment manufacturer, and Whayne Supply, a Kentucky com-
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Opinion of the Court
pany that serviced Caterpillar equipment. Id., at 64–65.
Lew
is's insurer (a Massachusetts corporation) intervened as
a plaintiff and asserted claims against both Whayne and Cat-
erpillar. Id., at 65. At that point, complete diversity was
lacking, as there was one plaintiff (Lewis) and one defendant
(Whayne) from Kentucky.
Lewis then settled his claims against Whayne. Ibid.
Caterpillar, thinking that the settlement would result in
Whayne's dismissal from the case, promptly removed the
case to federal court. Ibid. Lewis moved to remand,
pointing out that Whayne was still in the case because the
insurer had not settled its claim against Whayne. Id., at
65–66. Without addressing Lewis's argument, the District
Court erroneously denied the motion to remand, keeping the
case in federal court. Id., at 66. Whayne eventually set-
tled with the insurer and was voluntarily dismissed from the
case via a partial fnal judgment under Federal Rule of Civil
Procedure 54(b). See App. A to Brief for Respondents. That
dismissal left three completely diverse parties in the case:
Lewis (from Kentucky), the insurer (from Massachusetts),
and Caterpillar (from Delaware and Illinois).
The case then went to trial, at which Caterpillar prevailed.
519 U. S., at 66–67. Lewis appealed, and the Sixth Circuit
vacated the verdict. It held that the District Court should
have remanded the case because, at the time of removal,
complete diversity did not exist. Id., at 67.
This Court reversed. It held that, because Whayne had
been fully dismissed, “the jurisdictional defect [had been]
cured, i. e., complete diversity [had been] established before
the trial commenced.” Id., at 73. Because “considerations
of fnality, effciency, and economy become overwhelming ”
after “a diversity case has been tried in federal court,” the
Court held that the verdict could stand despite the District
Court's “statutory misstep” in denying the motion to re-
mand. Id., at 73, 75, 77. On the other hand, the Court
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430 HAIN
CELESTIAL GROUP, INC. v. PALMQUIST
Opinion of the Court
stated, had the jurisdictional defect not been cured and in-
stead
“lingered through judgment,” then vacatur would have
been required. Id., at 76–77.
B
The core dispute in this case is whether Whole Foods's
erroneous dismissal before fnal judgment cured the jurisdic-
tional defect that existed at the time of removal. It did not.
Because the jurisdictional defect lingered through judgment,
the judgment “must be vacated.” Id., at 77.
When Hain removed this case to federal court, the District
Court was required to determine whether it had jurisdiction
by ensuring that none of the plaintiffs was from the same
State as any of the defendants. Because Whole Foods (a
defendant) and the Palmquists (the plaintiffs) were all Texas
citizens, the District Court lacked jurisdiction. It then tried
to cure that jurisdictional defect by dismissing Whole Foods
as improperly joined.
That dismissal, the Fifth Circuit held, was erroneous. It
was also “[i]nterlocutory,” meaning that it did “not dispose
of the whole case.” Dupree v. Younger, 598 U. S. 729, 734
(2023). The “ `general rule' ” is that parties cannot immedi-
ately appeal interlocutory orders and must instead wait until
the end of the case, when those orders “merge into the fnal
judgment” and are “reviewable on appeal” from that judg-
ment. Id., at 735 (quoting Quackenbush v. Allstate Ins. Co.,
517 U. S. 706, 712 (1996)). Under that general rule, once
the District Court entered fnal judgment in Hain's favor,
the court's earlier jurisdictional holding merged into the
judgment and was reviewable by the Court of Appeals as
part of the Palmquists' post-trial appeal.
On appeal, the question before the Court of Appeals was
whether the District Court had correctly dismissed Whole
Foods at the outset. If it had, then this case would be more
like Caterpillar, where the District Court correctly and f-
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Opinion of the Court
nally dismissed Whayne with the parties' consent and left
beh
ind a completely diverse set of parties.
Whole Foods, however, was not dismissed correctly, and
the interlocutory nature of that dismissal meant that it was
reversible on appeal from the fnal judgment in Hain's favor.
Whole Foods thus was only temporarily and erroneously re-
moved from the case; it was not “gone for good.” Royal
Canin U. S. A., Inc. v. Wullschleger, 604 U. S. 22, 33 (2025).
When the Fifth Circuit reversed the District Court's error,
it restored Whole Foods to the case and correctly held that
the jurisdictional defect had not been cured. That meant
that the defect “lingered through judgment” and that the
District Court's judgment therefore “must be vacated.”
Caterpillar, 519 U. S., at 77.
In Hain's view, the correctness of the District Court's dis-
missal is irrelevant because, like in Caterpillar, the parties
were completely diverse by the time of fnal judgment.
Hain is mistaken. This Court has never held that a district
court can create jurisdiction through its own mistakes. A
rule to the contrary would permit courts to enlarge their
jurisdiction beyond the limits Congress imposed. Cf. Kok-
konen v. Guardian Life Ins. Co. of America, 511 U. S. 375,
377 (1994) (“Federal courts . . . possess only that power au-
thorized by Constitution and statute, which is not to be ex-
panded by judicial decree” (citations omitted)).
Hain also appeals to effciency, arguing that it would be
wasteful to send this case back to state court for a new trial.
This argument also fails. To be sure, Caterpillar recog-
nized that “considerations of fnality, effciency, and economy
become overwhelming ” after “a diversity case has been tried
in federal court.” 519 U. S., at 75. Those considerations,
however, were relevant only to excusing noncompliance with
the removal statute's requirement “that there be complete
diversity at the time of removal” after a jurisdictional defect
had been properly and fnally cured. Grupo Datafux, 541

432 HAIN
CELESTIAL GROUP, INC. v. PALMQUIST
Opinion of the Court
U. S., at 574. As to the jurisdictional requirement itself,
C
aterpillar held that an uncured jurisdictional defect means
that “the judgment must be vacated,” 519 U. S., at 76–77,
regardless of how effcient it might be to leave the judgment
in place. That the parties may need to litigate a new trial
in state court does not change the jurisdictional analysis or
make the District Court's error an effective cure.
3
III
As a fallback, Hain argues that, even if the jurisdictional
defect was not cured, Whole Foods should now be dismissed
under Federal Rule of Civil Procedure 21. That Rule per-
mits a federal court “on its own” to “add or drop a party”
“on just terms.” This argument is unavailing.
4
In Newman-Green, Inc. v. Alfonzo-Larrain, 490 U. S. 826
(1989), this Court held that, in appropriate circumstances,
courts may use Rule 21 “to dismiss a dispensable nondiverse
party.” Id., at 833, 837. To do so, courts must “carefully
consider whether the dismissal of a nondiverse party will
prejudice any of the parties in the litigation,” as “[i]t may be
that the presence of the nondiverse party produced a tactical
advantage for one party or another.” Id., at 838.
3
Other procedural mechanisms may be available to reduce wasteful liti-
gation. For instance, both partial fnal judgment under Federal Rule of
Civil Procedure 54(b) and certifcation under 28 U. S. C. § 1292(b) allow
district courts to certify matters for early appeal. Those procedures
could help resolve any uncertainty over whether a nondiverse party
should remain in the case at the time of removal and avoid the need to
wait until a post-trial appeal. See Tr. of Oral Arg. 20–23, 34–36.
4
The Palmquists contend the Rule 21 argument was forfeited, but it is
fairly included within the question presented, was raised in the petition for
certiorari, and was pressed before the Fifth Circuit. See Pet. for Cert. i,
22–24 (arguing that “appellate courts . . . ha[ve] dismissed dispensable
nondiverse parties in order to preserve jurisdiction as to diverse parties”
and citing Newman-Green, Inc. v. Al fonzo-Larrain, 490 U. S. 826, 834–836
(1989)); Brief for Whole Foods in No. 23–40197 (CA5), p. 16; see also this
Court's Rule 14.1(a).
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This case is very different from Newman-Green. Here,
the
defendants are seeking dismissal of a nondiverse defend-
ant, whereas in Newman-Green, the plaintiff sought the dis-
missal. Id., at 829. The identity of the party asking for the
dismissal is important because “[t]he plaintiff is `the master
of the complaint,' ” and generally has the right to choose
whether to proceed in federal or state court. Royal Canin,
604 U. S., at 35. Dismissing a nondiverse party with the
plaintiff 's consent is consistent with that right, as is a plain-
tiff 's ability to amend the complaint to “bring the suit either
newly within or newly outside a federal court's jurisdiction.”
Id., at 35–36.
Hain's proposed use of Rule 21, however, would force the
Palmquists to litigate this case in federal court against their
wishes and despite their right to control the forum for this
case. Hain cites no cases in which a court used Rule 21,
over the plaintiff 's consistent objections, to dismiss a prop-
erly joined defendant to preserve jurisdiction over an incor-
rectly removed case that never should have been in federal
court. That lack of authority is not surprising. The preju-
dice to the plaintiff in such circumstances is clear, for “plain-
tiffs are ordinarily allowed to select whatever forum they
consider most advantageous.” Atlantic Marine Constr. Co.
v. United States Dist. Court for Western Dist. of Tex., 571
U. S. 49, 63 (2013). The Palmquists exercised their right to
choose a state forum by purposefully and properly joining a
nondiverse defendant against whom they could not proceed
in federal court, and diligently asserted that right by
promptly moving to remand the case to state court. The
decision to structure their case in this way was the Palm-
quists' to make; Rule 21 does not permit a court or a defend-
ant to override their choice in these circumstances.
5
5
Some courts have used Rule 21 to dismiss nondiverse parties joined
after the case was properly removed to federal court. See, e. g., Gorfnkle
v. U. S. Airways, Inc., 431 F. 3d 19, 21–23 (CA1 2005). Because Whole
Foods was named in the original state-court complaint in this case, the
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434 HAIN
CELESTIAL GROUP, INC. v. PALMQUIST
Thomas, J., concurring
IV
The
District Court's erroneous dismissal of Whole Foods
did not cure the jurisdictional defect that existed when this
case was improperly removed to federal court. The Court
of Appeals therefore correctly vacated the judgment in
Hain's favor. The judgment of the Court of Appeals is af-
frmed, and the case is remanded for further proceedings
consistent with this opinion.
It is so ordered.
Justice Thomas, concurring.
I join the Court's opinion in full. I write separately to
note my skepticism of the doctrine of “improper joinder,”
which the District Court invoked to dismiss Whole Foods in
this case. The doctrine appears to allow federal courts to
enlarge their jurisdiction by assessing the merits of claims
over which they lack jurisdiction.
“Federal courts are courts of limited jurisdiction.” Kok-
konen v. Guardian Life Ins. Co. of America, 511 U. S. 375,
377 (1994). As “an essential ingredient of separation and
equilibration of powers,” the Constitution gives Congress
broad power over the scope of federal courts' jurisdiction.
Steel Co. v. Citizens for Better Environment, 523 U. S. 83,
101 (1998). “When we assume jurisdiction too hastily, we risk
aggrandizing ourselves at the expense of the political
branches.” Monsalvo Velazquez v. Bondi, 604 U. S. 712, 737
(2025) (Thomas, J., dissenting). Accordingly, if a federal
court determines that it lacks jurisdiction in a case, “the only
function remaining to the court is that of announcing the fact
and dismissing the cause.” Ex parte McCardle, 7 Wall. 506,
514 (1869).
Court expresses no view on whether using Rule 21 to dismiss a nondiverse
party added after a proper removal is appropriate. The Court also ex-
presses no view as to Rule 21's role in cases originally fled by plaintiffs
in federal court. See, e. g., Publicker Industries, Inc. v. Roman Ceramics
Corp., 603 F. 2d 1065, 1067, 1069 (CA3 1979).
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435
Thomas, J., concurring
Federal courts therefore “must determine that they have
jur
isdiction before proceeding to the merits.” Lance v. Cof-
fman, 549 U. S. 437, 439 (2007) (per curiam). “The require-
ment that jurisdiction be established as a threshold matter
spring[s] from the nature and limits of the judicial power of
the United States and is infexible and without exception.”
Steel Co., 523 U. S., at 94–95 (internal quotation marks omit-
ted). “For a court to pronounce upon” the merits “when it
has no jurisdiction to do so is, by very defnition, for a court
to act ultra vires.” Id., at 101–102.
In this case, federal jurisdiction was based on diversity of
citizenship. The removing defendant, Hain Celestial Group,
invoked federal jurisdiction under 28 U. S. C. § 1332(a), which
gives district courts jurisdiction over “civil actions where
the matter in controversy exceeds the sum or value of
$75,000 . . . and is between . . . citizens of different States.”
This Court has always interpreted § 1332(a)'s language “to
require `complete diversity,' ” meaning that a federal court
can exercise jurisdiction only if no plaintiff shares state citi-
zenship with any defendant. Carden v. Arkoma Associates,
494 U. S. 185, 187 (1990) (citing Strawbridge v. Curtiss, 3
Cranch 267 (1806)).
Although the parties in this case were not completely di-
verse, the District Court exercised jurisdiction based on the
doctrine of “improper joinder.” Under that doctrine, fed-
eral courts exercise jurisdiction over cases that originally
involved nondiverse defendants by frst deeming the claims
against those nondiverse defendants suffciently weak on the
merits and then dismissing them. See, e. g., International
Energy Ventures Mgmt., L.L.C. v. United Energy Group,
Ltd., 818 F. 3d 193, 205–209 (CA5 2016). Here, the Palm-
quists, Texas citizens, sued both an out-of-state defendant,
Hain Celestial Group, and a Texas defendant, Whole Foods.
The District Court therefore lacked jurisdiction over the
case when it was removed to federal court. The District
Court nonetheless proceeded to dismiss Whole Foods based
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436 HAIN
CELESTIAL GROUP, INC. v. PALMQUIST
Thomas, J., concurring
on its merits assessment that there was not a “reasonable
basis
to predict that [the Palmquists] could recover from
Whole Foods” under Texas products-liability law. App. to
Pet. for Cert. 25a–26a. After dismissing Whole Foods, it
adjudicated the claims against Hain Celestial on the merits.
The Fifth Circuit vacated that merits judgment for lack of
jurisdiction, but not because it thought that conducting an
improper-joinder inquiry was inappropriate. 103 F. 4th 294,
302–307 (2024). It simply thought that the Palmquists pos-
sibly stated meritorious claims against Whole Foods under
Texas law. See id., at 305–307. It reaffrmed that the
improper-joinder doctrine allows federal courts to engage in
a “Rule 12(b)(6)-type analysis” of claims against nondiverse
defendants, albeit with legal ambiguities resolved in the
plaintiffs' favor. Id., at 306. Federal Rule of Civil Proce-
dure 12(b)(6) dismissals, of course, are merits determina-
tions. See Federated Department Stores, Inc. v. Moitie, 452
U. S. 394, 399, n. 3 (1981).
Other federal courts adopt a similar approach to dismiss
claims against nondiverse parties. See, e. g., Johnson v.
Midwest Div.-RBH, LLC, 88 F. 4th 731, 735–736 (CA8 2023);
Jerome-Duncan, Inc. v. Auto-By-Tel, L. L. C., 176 F. 3d 904,
907–909 (CA6 1999); Legg v. Wyeth, 428 F. 3d 1317, 1324,
1320–1325 (CA11 2005). Courts justify this approach based
on a group of this Court's early-20th-century precedents that
recognized a doctrine called fraudulent joinder. See, e. g.,
Alabama Great Southern R. Co. v. Thompson, 200 U. S. 206,
217 (1906).*
*Many Circuits still use the “fraudulent joinder” term today, even when
they engage in the same merits analysis that the Fifth Circuit more accu-
rately calls improper joinder. See, e. g., Johnson, 88 F. 4th, at 735–736
(holding that “joinder . . . was fraudulent” because state-law claim was
unlikely to succeed on the merits); Jerome-Duncan, Inc., 176 F. 3d, at 907–
909 (affrming “fraudulent joinder” dismissal because of weakness of claim
under state law); Cline v. Dart Transit Co., 804 Fed. Appx. 307, 312 (CA6
2020) (holding that “fraudulent joinder occurred” because plaintiff lacked
“a colorable cause of action”).
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437
Thomas, J., concurring
But this Court's precedents do not support the lower
cour
ts' more recent approach. As I read them, this Court's
“fraudulent joinder” precedents concerned only whether the
plaintiff avoided federal diversity jurisdiction by bad faith or
actual fraud—such as lying about a party's conduct or citi-
zenship. See Alabama Great Southern R. Co., 200 U. S., at
218 (asking whether the plaintiff “attempt[ed] to commit a
fraud upon the jurisdiction of the Federal courts”); Illinois
Central R. Co. v. Sheegog, 215 U. S. 308, 316 (1909) (asking
whether a claim was “fraudulent and false”); Mecom v. Fitz-
simmons Drilling Co., 284 U. S. 183, 190 (1931) (asking
whether the plaintiff committed “actual fraud”). These
precedents were limited to cases of “extreme abuse.” Mur-
riel-Don Coal Co. v. Aspen Ins. UK Ltd., 790 F. Supp. 2d
590, 596 (ED Ky. 2011) (Thapar, J.). Unlike the lower courts'
more recent decisions, they did not appear to turn on the
strength of the claims on the merits.
Federal courts sitting in diversity likely cannot dismiss
nondiverse parties based on their view of the merits of the
claims against those parties. Doing so appears unfaithful to
Congress's limits on our diversity jurisdiction and inconsist-
ent with this Court's precedents. As Judge Thapar has put
it, the improper-joinder doctrine “requires federal courts to
exercise jurisdiction where none exists over questions of
state law that the state courts are better suited to address
themselves.” Id., at 597. In a future case where the issue
is briefed and squarely presented, this Court should consider
the propriety of the improper-joinder doctrine.
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Reporter’s Note
The attached opinion has been revised to refect the usual publication
and citation style of the United States Reports. The revised pagination
makes available the offcial United States Reports citation in advance of
publication. The syllabus has been prepared by the Reporter of Decisions
for the convenience of the reader and constitutes no part of the opinion of
the Court. A list of counsel who argued or fled briefs in this case, and
who were members of the bar of this Court at the time this case was
argued, has been inserted following the syllabus. Other revisions may
include adjustments to formatting, captions, citation form, and any errant
punctuation. The following additional edits were made:
None