Royal Canin U. S. A. v. Wullschleger

P R E L I M I N A R Y P R I N T
Volume 604 U. S. Part 1
Pages 22–44
OFFICIAL REPORTS
OF
T H E S U P R E M E C O U R T
January 15, 2025
REBECCA A. WOMELDORF
reporter of decisions
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22 OCTOBER
TERM, 2024
Syllabus
ROYAL CANIN U. S. A., INC., et al. v.
WUL
LSCHLEGER et al.
certiorari to the united states court of appeals for
the eighth circuit
No. 23–677. Argued October 7, 2024—Decided January 15, 2025
Respondent Anastasia Wullschleger sued petitioner Royal Canin U. S. A.,
Inc., in state court, alleging that Royal Canin had engaged in deceptive
marketing practices. Her original complaint asserted claims based on
both federal and state law. Royal Canin removed the case to federal
court under 28 U. S. C. § 1441(a). That removal was premised on Wull-
schleger's federal claim, which gave rise to federal-question jurisdiction
and also allowed the federal court to exercise supplemental jurisdiction
over Wullschleger's factually intertwined state claims. §§ 1331, 1367.
But federal court is not where Wullschleger wanted the case to be re-
solved. So she amended her complaint, deleting every mention of fed-
eral law, and petitioned the District Court for a remand to state court.
The District Court denied Wullschleger's request, but the Eighth Cir-
cuit reversed. In the Eighth Circuit's view, Wullschleger's amendment
had eliminated any basis for federal-question jurisdiction. And without
a federal question, the court concluded, there was no possibility of sup-
plemental jurisdiction over Wullschleger's state-law claims.
Held: When a plaintiff amends her complaint to delete the federal-law
claims that enabled removal to federal court, leaving only state-law
claims behind, the federal court loses supplemental jurisdiction over the
state claims, and the case must be remanded to state court. Pp. 30–44.
(a) Under the text of § 1367, the supplemental-jurisdiction statute, a
post-removal amendment to a complaint that eliminates any basis for
federal-question jurisdiction also divests a federal court of supplemental
jurisdiction over remaining state-law claims. Subsection (a) states that
“in any civil action of which the district courts have original jurisdiction,
the district courts shall have supplemental jurisdiction over all other
claims that are so related to claims in the action within such original
jurisdiction that they form part of the same case or controversy.” The
statute thus confers supplemental jurisdiction over state-law claims
sharing a suffcient factual relationship with the federal claims in a case.
And in Rockwell Int'l Corp. v. United States, 549 U. S. 457, 473–474,
this Court held that “when a plaintiff fles a complaint in federal court
and then voluntarily amends the complaint, courts look to the amended

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as: 604 U. S. 22 (2025)
23
Syllabus
complaint to determine jurisdiction.” So under § 1367(a), when the
plai
ntiff in an original case amends her complaint to withdraw the fed-
eral claims, leaving only state claims behind, she divests the federal
court of supplemental jurisdiction. And the result must be the same
in a removed case, because nothing in § 1367(a)'s text distinguishes
between cases removed to federal court and cases originally fled
there.
The exclusion from § 1367(a) of such post-amendment state-law claims
is refected in the text of § 1367(c). Subsection (c) provides that a dis-
trict court “may decline to exercise supplemental jurisdiction” over
state-law claims covered by § 1367(a)'s jurisdictional grant in three spe-
cifc situations where the state-law claims overshadow the federal claims
in a case. If § 1367(a)'s grant of jurisdiction included the leftover state
claims in an amended complaint, they too would have appeared on
§ 1367(c)'s list: Even more than the claims addressed there, they are ill-
suited to federal adjudication. That § 1367(c) makes no mention of such
claims demonstrates that § 1367(a) does not extend to them.
That result accords with Congress's usual view of how amended plead-
ings can affect jurisdiction. On that view, apparent in varied federal
statutes, an amendment can wipe the jurisdictional slate clean, giving
rise to a new analysis with a different conclusion. E. g., § 1653 (“[d]efec-
tive allegations of jurisdiction may be amended” so a case can come
within a federal court's jurisdiction); § 1446(b)(3) (even “if the case
stated by the initial pleading is not removable,” the defendant can re-
move the case after receiving “an amended pleading ” establishing a
basis for federal jurisdiction); § 1332(d)(7) (similar). And just the same
here: Section 1367 contemplates that when an amended complaint is
fled, the jurisdictional basis for the suit is reviewed anew. Pp. 31–34.
(b) That reading of § 1367 also parallels a slew of other procedural
rules linking jurisdiction to the amended, rather than initial, complaint.
In deciding which substantive claims to bring against which defendants,
a plaintiff can establish—or not—the basis for a federal court's subject-
matter jurisdiction. And her control over those matters extends be-
yond the time her frst complaint is fled. If a plaintiff amends her
complaint, the new pleading supersedes the old one and can bring the
suit either newly within or newly outside a federal court's jurisdiction.
Thus, as Rockwell explained, if “a plaintiff fles a complaint in federal
court and later voluntarily amends the complaint” to “withdraw[ ]” the
allegations supporting federal jurisdiction, that amendment “will defeat
jurisdiction” unless the withdrawn allegations were “replaced by oth-
ers” giving the court adjudicatory power. 549 U. S., at 473–474.

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YAL CANIN U. S. A., INC. v. WULLSCHLEGER
Syllabus
Rockwell's rule has a host of variations in both original and removed
federa
l cases. Adding federal claims can create original jurisdiction
where it once was wanting. See, e. g., ConnectU LLC v. Zuckerberg,
522 F. 3d 82, 91. And an amendment can either destroy or create juris-
diction in an original diversity case. See Owen Equipment & Erection
Co. v. Kroger, 437 U. S. 365, 374–377; Newman-Green, Inc. v. Al fonzo-
Larrain, 490 U. S. 826, 832–833. Similarly, if removing a case was im-
proper because the initial complaint did not contain a federal claim, the
plaintiff 's later assertion of such a claim establishes jurisdiction going
forward. See Pegram v. Herdrich, 530 U. S. 211, 215–216, and n. 2.
And by the same token, amending a complaint in a removed case to join
a non-diverse party destroys diversity jurisdiction, and the federal court
must remand the case to state court. See § 1447(e). In removed and
original cases alike, the rule that jurisdiction follows the operative
pleading ensures that the case, as it will actually be litigated, merits a
federal forum. Pp. 34–39.
(c) Royal Canin contends that this Court has twice before reached
the opposite conclusion—frst, in Carnegie-Mellon Univ. v. Cohill, 484
U. S. 343, and next in Rockwell, in a footnote. But in each case, the
relied-on passage is extraneous to the Court's holding and reasoning,
and so cannot bear the weight of Royal Canin's argument. The footnote
in Rockwell does state the rule Royal Canin propounds: “[W]hen a de-
fendant removes a case to federal court based on the presence of a fed-
eral claim,” it says, “an amendment eliminating the original basis for
federal jurisdiction generally does not defeat jurisdiction.” 549 U. S.,
at 474, n. 6. But Rockwell was an original federal case, not a removed
one, so its drive-by assertion of a jurisdictional rule for removed cases
was entirely outside the issue being decided. That dictum cannot over-
come the Court's analysis here or Rockwell's own core insight that fed-
eral courts “look to the amended complaint to determine jurisdiction.”
Id., at 474. Pp. 39–44.
75 F. 4th 918, affrmed.
Kagan, J., delivered the opinion for a unanimous Court.
Katherine B. Wellington argued the cause for petitioners.
With her on the briefs were Neal Kumar Katyal, Nathaniel
A. G. Zelinsky, Christopher M. Curran, Stephen D. Raber,
and Charles L. McCloud.
Ashley Keller argued the cause for respondents. With
her on the brief were Noah Heinz, Edward J. Coyne III,

Cite
as: 604 U. S. 22 (2025)
25
Opinion of the Court
Christopher S. Edwards, Michael L. McGlamry, Kimberly
J
. Johnson, and James P. Frickleton.*
Justice Kagan delivered the opinion of the Court.
If a complaint fled in state court asserts federal-law
claims, the defendant may remove the case to federal court.
See 28 U. S. C. § 1441(a). And if the complaint also asserts
state-law claims arising out of the same facts, the federal
court may adjudicate those claims too, in the exercise of what
is called supplemental jurisdiction. See § 1367.
This case presents a further question: What happens if,
after removal, the plaintiff amends her complaint to delete
all the federal-law claims, leaving nothing but state-law
claims behind? May the federal court still adjudicate the
now purely state-law suit? We hold that it may not. When
an amendment excises the federal-law claims that enabled
removal, the federal court loses its supplemental jurisdiction
*Briefs of amici curiae urging reversal were fled for the Chamber of
Commerce of the United States of America by William M. Jay, Benjamin
Hayes, and Jonathan D. Urick; for the DRI–Center for Law and Public
Policy by Mary Massaron; and for State Chambers of Commerce by Eric
Mahr, Claire L. Leonard, and Scott A. Eisman. Scott Dodson fled a
brief for the Center for Litigation and Courts as amicus curiae urging
vacatur.
A brief of amici curiae urging affrmance was fled for the State of
Tennessee et al. by Jonathan Skrmetti, Attorney General of Tennessee, J.
Matthew Rice, Solicitor General, and Matthew D. Cloutier, Assistant So-
licitor General, and by the Attorneys General for their respective States
as follows: Treg Taylor of Alaska, William Tong of Connecticut, Kathy
Jennings of Delaware, Ashley Moody of Florida, Kris W. Kobach of Kan-
sas, Liz Murrill of Louisiana, Dana Nessel of Michigan, Keith Ellison of
Minnesota, Lynn Fitch of Mississippi, Andrew Bailey of Missouri, Austin
Knudsen of Montana, Michael T. Hilgers of Nebraska, Matthew J. Platkin
of New Jersey, Raúl Torrez of New Mexico, Drew H. Wrigley of North
Dakota, Dave Yost of Ohio, Alan Wilson of South Carolina, Marty J.
Jackley of South Dakota, Ken Paxton of Texas, Sean D. Reyes of Utah,
and Jason Miyares of Virginia.
Thomas Fuller Ogden, pro se, fled a brief as amicus curiae.
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26 RO
YAL CANIN U. S. A., INC. v. WULLSCHLEGER
Opinion of the Court
over the related state-law claims. The case must therefore
retur
n to state court.
I
A
“Federal courts,” we have often explained, “are courts of
limited jurisdiction.” E. g., Kokkonen v. Guardian Life Ins.
Co. of America, 511 U. S. 375, 377 (1994). Limited frst by
the Constitution, to only the kinds of “Cases” and “Contro-
versies” listed in Article III. And for all lower federal
courts, limited as well by statute. Congress determines,
through its grants of jurisdiction, which suits those courts
can resolve. So, for example, Congress has always given
federal courts power to decide “diversity” cases, between
“citizens of different States” whose dispute involves more
than a stated sum (the so-called amount-in-controversy).
§ 1332(a). And of special importance here, Congress has
long conferred jurisdiction on federal courts to resolve cases
“arising under” federal law. § 1331.
“Arising under” jurisdiction—more often known as
federal-question jurisdiction—enables federal courts to de-
cide cases founded on federal law. A suit most typically falls
within that statutory grant “when federal law creates the
cause of action asserted.” Gunn v. Minton, 568 U. S. 251,
257 (2013). On rare occasions, the grant also covers a suit
containing state-law claims alone, because one or more of
them “necessarily raise[s]” a “substantial” and “actually dis-
puted” federal question. Id., at 258. Either way, the deter-
mination of jurisdiction is based only on the allegations in
the plaintiff 's “well-pleaded complaint”—not on any issue the
defendant may raise. Franchise Tax Bd. of Cal. v. Con-
struction Laborers Vacation Trust for Southern Cal., 463
U. S. 1, 9–10 (1983). That longstanding rule makes the com-
plaint—the plaintiff 's own claims and allegations—the key
to “arising under” jurisdiction. If the complaint presents no
federal question, a federal court may not hear the suit.
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Opinion of the Court
But if a complaint includes the requisite federal question,
a
federal court often has power to decide state-law questions
too. Suppose a complaint with two claims—one based on
federal, the other on state, law. This Court held in Mine
Workers v. Gibbs, 383 U. S. 715, 725 (1966), that a federal
court may exercise supplemental jurisdiction over the state
claim so long as it “derive[s] from” the same “nucleus of oper-
ative fact” as the federal one. The Gibbs Court reasoned
that when the two claims are so closely related, they make
up “but one constitutional `case' ”; and the Court presumed
that Congress wanted in that situation to confer jurisdiction
up to the Constitution's limit. Ibid. (quoting U. S. Const.,
Art. III, § 2, cl. 1); see Exxon Mobil Corp. v. Allapattah
Services, Inc., 545 U. S. 546, 553 (2005). Congress later con-
frmed that view, generally codifying Gibbs's supplemental-
jurisdiction rule in 28 U. S. C. § 1367 (whose text we will soon
consider, see infra, at 31–32). Under that statute, as under
Gibbs, jurisdiction over a federal-law claim brings with it
supplemental jurisdiction over a state-law claim arising from
the same facts. That derivative jurisdiction, though, is to
some extent discretionary; § 1367 spells out circumstances,
again derived from Gibbs, in which a federal court may de-
cline to hear a state claim falling within the statute's bounds.
See § 1367(c); Gibbs, 383 U. S., at 726–727.
And yet one more preparatory point: If a statute confers
federal jurisdiction over a suit, not only the plaintiff but also
the defendant can get it into federal court. Take the “aris-
ing under” statute: It grants federal district courts “origi-
nal jurisdiction” over cases presenting a federal question.
§ 1331; see § 1332 (similarly providing “original jurisdiction”
over diversity suits). The plaintiff may avail herself of that
jurisdiction (and of the opportunity § 1367 affords to add sup-
plemental state claims); but she also may fle her suit in state
court. If she takes the latter route, another statute then
gives the defendant an option. Because the case falls within
the federal courts' “original jurisdiction,” the defendant may
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28 RO
YAL CANIN U. S. A., INC. v. WULLSCHLEGER
Opinion of the Court
“remove[ ]” it from state to federal court. § 1441(a). And
there
the case (including supplemental state claims) usually
remains. Except that “[i]f at any time before fnal judgment
it appears that the district court lacks subject matter juris-
diction,” the case must be “remanded” to state court.
§ 1447(c). That is because, to return to where we started,
federal courts are courts of limited jurisdiction: When they
do not have (or no longer have) authorization to resolve a
suit, they must hand it over.
B
Before raising issues demanding a jurisdictional primer,
this case was all about the marketing of dog food. Peti-
tioner Royal Canin U. S. A., Inc., manufactures a brand of
dog food available only with a veterinarian's prescription—
and thus sold at a premium price. Respondent Anastasia
Wullschleger purchased the food, thinking it contained medi-
cation not found in off-the-shelf products. She later learned
it did not. Her suit, initially fled in a Missouri state court,
contends that Royal Canin's dog food is ordinary dog food:
The company sells the product with a prescription not be-
cause its ingredients make that necessary, but solely to fool
consumers into paying a jacked-up price. Her original com-
plaint asserted claims under the Missouri Merchandising
Practices Act and state antitrust law. It also alleged viola-
tions of the Federal Food, Drug, and Cosmetic Act (FDCA),
21 U. S. C. § 301 et seq.
And so began the procedural back-and-forth that eventu-
ally landed Wullschleger's case in this Court. Royal Canin
went frst: It removed the case to federal court based on the
asserted violations of the FDCA.
1
That removal properly
1
That frst step provoked an earlier jurisdictional battle, resolved in
favor of allowing removal and not at issue here. The dispute arose be-
cause Wullschleger's complaint alleged the FDCA violations not as inde-
pendent federal claims, but instead in support of her state claims. Did
the complaint, then, contain the needed federal question? The Court of

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Opinion of the Court
brought to the District Court not only Wullschleger's FDCA
clai
ms, but also her factually intertwined state-law claims.
The parties were thus set to litigate the entire suit in federal
court. But that is not where Wullschleger wanted the case
to be resolved. So she countered Royal Canin's move: She
amended her complaint to delete its every mention of the
FDCA, leaving her state claims to stand on their own. And
with that amended, all-state-law complaint in hand, she peti-
tioned the District Court to remand the case to state court.
Although the District Court denied Wullschleger's re-
quest, the Court of Appeals for the Eighth Circuit reversed
that decision and ordered a remand. See 75 F. 4th 918, 924
(2023).
2
In the Eighth Circuit's view, Wullschleger's amend-
ment had eliminated any basis for federal jurisdiction. An
amended complaint, the court reasoned, “[supersedes] an
original complaint and renders the original complaint with-
out legal effect.” Id., at 922 (alteration in original). And
noth i ng i n the amended complai nt suppor ted federa l-
question jurisdiction: It was, after all, now based entirely on
state law. Nor could the District Court now exercise sup-
plemental jurisdiction over Wullschleger's state-law claims.
“[T]he possibility of supplemental jurisdiction,” the court
reasoned, “vanished right alongside the once-present federal
questions.” Id., at 924. And that analysis held good even
though it was Royal Canin, rather than Wullschleger, that
Appeals held that it did because the meaning of the referenced FDCA
provisions was thoroughly embedded in, and integral to the success of,
Wu l lsch leger 's state-law clai ms. See Wullschl eger v. Ro ya l Can in
U. S. A., Inc., 953 F. 3d 519, 522 (CA8 2020) (citing Gunn v. Minton, 568
U. S. 251, 258 (2013)); see supra, at 26. We here treat that fnding of
federal-question jurisdiction as a given. And for ease of exposition, we
take a slight liberty throughout this opinion, referring to the original com-
plaint's FDCA allegations simply as federal claims.
2
Because the denial of a remand request is not immediately appealable,
see Caterpillar Inc. v. Lewis, 519 U. S. 61, 74 (1996), the issue reached the
Court of Appeals only after the District Court dismissed Wullschleger's
amended complaint on the merits.
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YAL CANIN U. S. A., INC. v. WULLSCHLEGER
Opinion of the Court
had brought the suit to the District Court: “It makes no dif-
ference
,” the Eighth Circuit stated, that the case “end[ed] up
in federal court through removal.” Id., at 922.
Other Courts of Appeals have reached the opposite conclu-
sion, holding that a post-removal amendment cannot divest
a federal court of jurisdiction.
3
On that view, “[t]he exist-
ence of subject matter jurisdiction is determined by examin-
ing the complaint as it existed at the time of removal.”
Harper v. AutoAlliance Int'l, Inc., 392 F. 3d 195, 210 (CA6
2004). So the District Court here would have retained sup-
plemental jurisdiction over Wullschleger's state-law claims
even after she amended her complaint to delete all her
federal-law ones.
We granted certiorari to resolve the Circuit split, 601 U. S.
1167 (2024), and we now affrm the decision below.
II
When a plaintiff amends her complaint following her suit's
removal, a federal court's jurisdiction depends on what the
new complaint says. If (as here) the plaintiff eliminates the
federal-law claims that enabled removal, leaving only state-
law claims behind, the court's power to decide the dispute
dissolves. With the loss of federal-question jurisdiction, the
court loses as well its supplemental jurisdiction over the
state claims. That conclusion fts the text of § 1367, govern-
ing supplemental jurisdiction. And it accords with a bevy
of rules hinging federal jurisdiction on the allegations made
in an amended complaint, because that complaint has become
the operative one. Royal Canin argues that our precedent
makes an exception for when an amendment follows a law-
3
Ching v. Mitre Corp., 921 F. 2d 11, 13 (CA1 1990); Collura v. Philadel-
phia, 590 Fed. Appx. 180, 184 (CA3 2014) (per curiam); Harless v. CSX
Hotels, Inc., 389 F. 3d 444, 448 (CA4 2004); Harper v. AutoAlliance Int'l,
Inc., 392 F. 3d 195, 210–211 (CA6 2004); Behlen v. Merrill Lynch, 311 F. 3d
1087, 1095 (CA11 2002).
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Opinion of the Court
suit's removal, but that is to read two bits of gratuitous lan-
g
uage for a good deal more than they are worth.
A
Begin with § 1367, entitled “Supplemental jurisdiction.”
Subsection (a) states the basic rule:
“Except as provided in subsections (b) and (c) or as ex-
pressly provided otherwise by Federal statute, in any
civil action of which the district courts have original ju-
risdiction, the district courts shall have supplemental ju-
risdiction over all other claims that are so related to
claims in the action within such original jurisdiction that
they form part of the same case or controversy under
Article III of the United States Constitution.”
The subsection thus takes as its starting point claims within
a federal district court's original jurisdiction—because, say,
they turn on federal law. See § 1331. It then confers au-
thority on the court to decide certain “other” claims in the
same suit, involving only state law. That added authority—
the court's supplemental jurisdiction—extends to claims “so
related to” the claims supporting original jurisdiction as to
form “part of the same [constitutional] case.” And that
needed relationship, Gibbs explains, is one of fact: The fed-
eral court has supplemental jurisdiction over state-law
claims sharing a “common nucleus of operative fact” with the
federal-law ones. 383 U. S., at 725; see supra, at 27.
Skip down a bit and subsection (c) explains that the supple-
mental jurisdiction just conferred is in some measure discre-
tionary. That subsection provides that a district court “may
decline to exercise supplemental jurisdiction” in three spe-
cifc situations: (1) if the supplemental claim “raises a novel
or complex issue of State law”; (2) if the supplemental claim
“substantially predominates” over the claims within the
court's original jurisdiction; and (3) if the district court “has
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32 RO
YAL CANIN U. S. A., INC. v. WULLSCHLEGER
Opinion of the Court
dismissed all claims over which it has original jurisdiction.”
4
In
all those contexts, federal law is not where the real action
is. So although supplemental jurisdiction persists, the dis-
trict court need not exercise it: Instead, the court may (and
indeed, ordinarily should) kick the case to state court. See
Gibbs, 383 U. S., at 726–727.
In addressing the text of § 1367, Royal Canin argues pri-
marily from the frst subsection's grant of jurisdiction. The
language there is “broad,” the company says: Section 1367(a)
grants “supplemental jurisdiction over `all other claims'
within the case or controversy, unless Congress `expressly
provided otherwise.' ” Reply Brief 2 (emphasis in original).
And Congress did not expressly provide that an amendment
deleting federal claims eliminates supplemental jurisdiction.
See id., at 4–5. The upshot, Royal Canin says, is the rule it
espouses: The amendment of a complaint following removal
of a suit to federal court cannot divest that court of supple-
mental jurisdiction.
But that positi on founders on an undisputed poi nt:
Nothing in § 1367's text—including in the text Royal Canin
highlights—distinguishes between cases removed to federal
court and cases originally fled there. See Tr. of Oral Arg.
7–8. Whatever that text says about removed cases, it also
says about original ones, and vice versa. That means if (as
Royal Canin urges) § 1367(a)'s language prevents an amend-
ment from ousting supplemental jurisdiction in removed
cases, then so too it does in original ones. But here is the
rub: In original cases, this Court has already reached the
opposite conclusion. The pertinent rule comes from Rock-
well Int'l Corp. v. United States, 549 U. S. 457, 473–474
(2007): “[W]hen a plaintiff fles a complaint in federal court
and then voluntarily amends the complaint, courts look to
the amended complaint to determine jurisdiction.” So when
4
A fourth, more general provision, which neither party thinks relevant
here, allows a court to decline supplemental jurisdiction “in exceptional
circumstances,” for “other compelling reasons.” 28 U. S. C. § 1367(c)(4).
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Opinion of the Court
the plaintiff in an original case amends her complaint to
w
ithdraw the federal claims, leaving only state claims be-
hind, she divests the federal court of adjudicatory power.
See ibid. Royal Canin concedes that result, as it must.
See Tr. of Oral Arg. 6–7. The position it adopts—applying
only in removed cases—is indeed designed not to collide with
Rockwell's ruling. But once § 1367(a) is taken as consistent
with Rockwell, it cannot say what the company posits.
Under that provision—as under Rockwell—an amendment
excising all federal claims divests a court of supplemental
jurisdiction over the remaining state claims in an original
case. And if in an original case, then also in a removed
case—because, again, § 1367(a) draws no distinction between
the two.
The exclusion from § 1367(a) of such post-amendment
state-law claims is refected in the text of § 1367(c). Recall
that § 1367(c) describes three contexts in which state-law
claims, though covered by § 1367(a)'s jurisdictional grant,
are often better given to state courts. See supra, at 31–32.
If § 1367(a)'s grant included the leftover state claims in
an amended complaint, they too would have appeared on
§ 1367(c)'s list: Even more than the claims addressed there,
they are ill-suited to federal adjudication. The leftover
state claims, after all, are now the entirety of the plaintiff 's
suit. Federa l clai ms are not just subordi nate, as i n
§§ 1367(c)(1) and (2), but gone. And gone for good as well.
When federal claims are dismissed by the district court,
as in § 1367(c)(3), an appellate court may yet revive them;
but that cannot happen when the plaintiff has excised them
through a proper amendment. So, again, it follows: If
§ 1367(a) conferred supplemental jurisdiction over the claims
here, § 1367(c) would make that jurisdiction discretionary.
That § 1367(c) does not do so—that even while it addresses,
for example, dismissals of federal claims, it makes no mention
of amendments deleting them—shows that § 1367(a) does not
extend so far. Or otherwise said, there is no discretion to
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YAL CANIN U. S. A., INC. v. WULLSCHLEGER
Opinion of the Court
decline supplemental jurisdiction here because there is no
supplement
al jurisdiction at all. Once the plaintiff has
ditched all claims involving federal questions, the leftover
state claims are supplemental to nothing—and § 1367(a) does
not authorize a federal court to resolve them.
That result accords with Congress's usual view of how
amended pleadings can affect jurisdiction. On that view, ap-
parent in varied federal statutes, an amendment can wipe
the jurisdictional slate clean, giving rise to a new analysis
with a different conclusion. Consider 28 U. S. C. § 1653: It
states broadly that, in both trial and appellate courts, “[d]e-
fective allegations of jurisdiction may be amended” to ensure
that a case can go forward. So a case falling outside the
federal court's jurisdiction can come within it by virtue of an
amendment. Or take the statute laying out procedures for
removal. It provides that even “if the case stated by the
initial pleading is not removable,” an amendment may make
it so: The defendant can remove the case after receiving
“an amended pleading ” establishing that the case is newly
subject to federal jurisdiction. § 1446(b)(3); see § 1332(d)(7)
(similarly providing that an “amended complaint” in a pro-
posed class action may create “[f]ederal jurisdiction”). In
such statutes, Congress conceives of amendments as having
the potential to alter jurisdiction. And just the same here.
Section 1367 contemplates that when an amended complaint
is fled, the jurisdictional basis for the suit is reviewed anew.
If nothing in the amended complaint now falls “within [the
federal court's] original jurisdiction,” then neither does any-
thing fall within the court's “supplemental jurisdiction.”
§ 1367(a). In the superseding pleading, the state-law claims
are just state-law claims, outside § 1367(a)'s purview.
B
That reading of § 1367 also parallels a slew of other,
mainly judge-made procedural rules linking jurisdiction to
the amended, rather than initial, complaint. In multiple

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contexts—involving both cases brought in federal court and
cases
removed there—courts conceive of amendments to
pleadings as potentially jurisdiction-changing events. The
amended complaint becomes the operative one; and in taking
the place of what has come before, it can either create or
destroy jurisdiction. Section 1367, as laid out above, fts
hand in glove with—indeed, embodies—that familiar ap-
proach. A post-removal amendment can divest a federal
court of its supplemental jurisdiction because—as the usual
procedural principle holds—jurisdiction follows from (and
only from) the operative pleading.
Begin from the beginning: The plaintiff is “the master of
the complaint,” and therefore controls much about her suit.
Caterpillar Inc. v. Williams, 482 U. S. 386, 398–399 (1987).
She gets to determine which substantive claims to bring
agai nst wh ich defendants. And i n so doi ng, she can
establish—or not—the basis for a federal court's subject-
matter jurisdiction. She may, for example, name only de-
fendants who come from a different State, or instead add one
from her own State and thereby destroy diversity of citizen-
ship. See § 1332(a). Or in cases like this one, she may
decide to plead federal-law claims, or instead to allege
state-law claims alone and thus ensure a state forum. See
§ 1331; supra, at 26 (describing the well-pleaded complaint
rule).
And the plaintiff 's control over those matters extends be-
yond the time her frst complaint is fled. If a plaintiff
amends her complaint, the new pleading “supersedes” the old
one: The “original pleading no longer performs any function
in the case.” 6 C. Wright, A. Miller, & M. Kane, Federal
Practice and Procedure § 1476, pp. 636–637 (3d ed. 2010). Or
as we put the matter over a century ago: “When a petition
is amended,” the “cause proceeds on the amended petition.”
Washer v. Bullitt County, 110 U. S. 558, 562 (1884). So
changes in parties, or changes in claims, effectively remake
the suit. And that includes its jurisdictional basis: The re-

36 RO
YAL CANIN U. S. A., INC. v. WULLSCHLEGER
Opinion of the Court
confguration accomplished by an amendment may bring the
suit
either newly within or newly outside a federal court's
jurisdiction.
That idea is the one Rockwell invoked, as earlier noted.
See supra, at 32–33. Recall the situation there considered:
“[A] plaintiff fles a complaint in federal court and later vol-
untarily amends the complaint” to “withdraw[ ]” the allega-
tions supporting federal jurisdiction. Rockwell, 549 U. S.,
at 473–474. Should the suit proceed? “[C]ourts,” Rockwell
replied, “look to the amended complaint to determine juris-
diction.” Id., at 474. That complaint is now the operative
one; the old complaint has become irrelevant. So unless
the withdrawn allegations were “replaced by others” giving
the court adjudicatory power, the plaintiff 's amendment
“will defeat jurisdiction.” Id., at 473. Or more specifcally:
If a plaintiff fles a suit in federal court based on federal
claims and later scraps those claims, the federal court can-
not go forward with a now all-state-claim suit. See id.,
at 473–474.
5
That rule for original federal cases has a host of variations,
each tying jurisdiction to an amended pleading. If, as Rock-
well spelled out, eliminating federal claims in such a suit can
destroy federal jurisdiction, the opposite is also true: Adding
federal claims can create federal jurisdiction where it once
was wanting. See, e. g., ConnectU LLC v. Zuckerberg, 522
F. 3d 82, 91 (CA1 2008) (holding that an amended complaint,
which “replaced the original complaint lock, stock, and bar-
5
The Rockwell Court distinguished its rule from another, operating in
diversity cases, which evaluates a party's citizenship (e. g., whether the
defendant is in fact from New York) at the time a suit is brought, and
never again later. See 549 U. S., at 473 (citing, e. g., Anderson v. Watt,
138 U. S. 694, 701 (1891)). That so-called time-of-fling rule, Rockwell
explained, concerns only the actual “state of things” relevant to ju-
risdiction—meaning, the facts on the ground, rather than (as addressed
here) the claims and parties that the plaintiff includes in a complaint. 549
U. S., at 473; see 75 F. 4th 918, 922–923 (CA8 2023) (case below) (discussing
that distinction).
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rel,” conferred jurisdiction). And so too, an amendment can
either
destroy or create jurisdiction in an original diversity
case. The addition of a non-diverse party in such a case typ-
ically destroys diversity jurisdiction, requiring the case's dis-
missal. See Owen Equipment & Erection Co. v. Kroger, 437
U. S. 365, 374–377 (1978) (stating that an amendment assert-
ing claims against a non-diverse party “destroy[s]” complete
diversity “just as surely as” joining that party in the frst
instance); see also, e. g., American Fiber & Finishing, Inc.
v. Tyco Healthcare Group, LP, 362 F. 3d 136, 139 (CA1 2004).
6
Conversely, the eliminati on of a non-diverse defendant
by way of amendment ensures that a case can proceed in
federal court, though it could not have done so before. See
Newman-Green, Inc. v. Alfonzo-Larrain, 490 U. S. 826,
832–833 (1989). In short, the rule in original cases that ju-
risdiction follows the amended (i. e., now operative) pleading
applies across the board.
And still more: Similar rules have long applied in the re-
moval context. Not across the board, of course, else this
case would not have arisen: The very issue here is whether,
in a removed case (as in an original one), an amended com-
plaint dropping federal claims destroys jurisdiction. But in
two of the other situations discussed above, the rule in re-
moved cases is the same as the rule in original ones.
7
First,
in removed cases too, amending a complaint to add a federal
claim creates federal jurisdiction when it did not previously
exist. So even if removing a case was improper because the
initial complaint did not contain a federal claim, the plain-
6
That general rule does not apply when an amendment merely substi-
tutes a successor-in-interest for the frst-named defendant. In that situa-
tion, the former steps into the latter's shoes, and the diversity jurisdiction
founded on the initial complaint thus continues. See Freeport-McMoRan
Inc. v. K N Energy, Inc., 498 U. S. 426, 428–429 (1991) (per curiam).
7
To our knowledge, no appellate decision addresses whether in the fnal
situation discussed—when an amendment eliminates a non-diverse
party—the rule in removed cases similarly follows the rule in original
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38 RO
YAL CANIN U. S. A., INC. v. WULLSCHLEGER
Opinion of the Court
tiff 's later assertion of such a claim establishes jurisdiction
goi
ng forward. See Pegram v. Herdrich, 530 U. S. 211, 215–
216, and n. 2 (2000); Bernstein v. Lind-Waldock & Co., 738
F. 2d 179, 185–186 (CA7 1984) (Posner, J.). The federal court
can thus resolve both the newly added federal-law claim and
the now supplemental state-law ones. See id., at 186–187.
And second, in removed cases too, amending a complaint to
join a non-diverse party destroys diversity jurisdiction. So
if such a joinder occurs after removal, the federal court must
remand the case to the state court it began in. See § 1447(e);
Powerex Corp. v. Reliant Energy Services, Inc., 551 U. S.
224, 231–232 (2007). Once again, federal jurisdiction—or its
absence—follows from the amended complaint.
8
The uniformity of that principle, as between original and
removed cases, is not surprising. The appropriateness of
federal jurisdiction—or the lack thereof—does not depend on
whether the plaintiff frst fled suit in federal or state court.
8
Royal Canin offers up something of an exception: In both original and
removed cases, an amendment reducing the alleged amount-in-controversy
to below the statutory threshold—like a post-fling development that
makes recovering the needed amount impossible—will usually not destroy
diversity jurisdiction. See St. Paul Mercury Indemnity Co. v. Red Cab
Co., 303 U. S. 283, 289, 292 (1938); Brief for Petitioners 20. But that rule
is inapposite here, by virtue of its subject and function alike. First, the
rule more concerns a fact on the ground—that is, the value of a suit—than
it does the plaintiff 's selection of claims and parties. So this Court has
viewed it as analogous to the time-of-fling rule applying to citizenship,
which also assesses a factual issue relevant to jurisdiction only at the suit's
outset. See St. Paul Mercury, 303 U. S., at 294–295; Rosado v. Wyman,
397 U. S. 397, 405, n. 6 (1970); supra, at 36, n. 5. Second, the rule responds
to the diffculties of assessing a suit's value and the likelihood that the
calculation will change over the course of litigation. Especially given that
the alleged amount-in-controversy does not cap damages, “constant litiga-
tion” over the matter, having the potential to alter a court's jurisdiction,
“would be wasteful.” Grupo Datafux v. Atlas Global Group, L. P., 541
U. S. 567, 580–581 (2004) (making the same point about changes in citizen-
ship). But as all the examples given above show, we have never held
such a concern to limit the effect of the plaintiff 's decision, as the master
of her complaint, to add or subtract claims or parties.
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Rather, it depends, in either event, on the substance of the
suit
—the legal basis of the claims (federal or state?) and the
citizenship of the parties (diverse or not?). (That focus on
substance is indeed why original jurisdiction and removal
jurisdiction generally mirror each other in scope. See
§ 1441(a).) So in a removed no less than in an original case,
the rule that jurisdiction follows the operative pleading
serves a critical function. It too ensures that the case, as it
will actually be litigated, merits a federal forum.
And with all that recognized, the answer to the disputed
question here becomes yet more certain: On top of § 1367,
a panoply of procedural rules shows that a post-removal
amendment excising all federal claims destroys federal juris-
diction. Under those rules, the presence of jurisdiction, in
removed as in original cases, hinges on the amended, now
operative pleading. By adding or subtracting claims or par-
ties, and thus reframing the suit, that pleading can alter a
federal court's authority. And so it is here. When a plain-
tiff, after removal, cuts out all her federal-law claims,
federal-question jurisdiction dissolves. And with any fed-
eral anchor gone, supplemental jurisdiction over the residual
state claims disappears as well. The operative pleading no
longer supports federal jurisdiction, and the federal court
must remand the case to the state court where it started.
C
Royal Canin contends that this Court has twice before
reached the opposite conclusion—frst, in Carnegie-Mellon
Univ. v. Cohill, 484 U. S. 343 (1988), and next in Rockwell, in
a footnote to the analysis we have related above. See supra,
at 32–33, 36. But in each case, the relied-on passage is ex-
traneous to the Court's holding and reasoning, and so cannot
bear the weight of Royal Canin's argument.
Begin with Cohill, which shares the procedural posture of
this case but asked and answered a different question.
There, as here, the plaintiff fled a suit in state court, assert-
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40 RO
YAL CANIN U. S. A., INC. v. WULLSCHLEGER
Opinion of the Court
ing both federal and state claims; the defendant removed the
suit
to federal court; and the plaintiff then dropped her fed-
eral claim and sought a remand. The District Court granted
that request over the defendant's objection. But in oppos-
ing that ruling, the defendant did not argue (à la Royal
Canin) that the court should have held on to the case.
Rather, the defendant urged that the court should have dis-
missed the case outright instead of remanding it. (The dif-
ference mattered because the statute of limitations had by
then expired, and a dismissal would have ended the suit.)
The disputed issue was thus not about keeping the case in
federal court, but about two different ways of expelling it.
Or as Cohill put it: The question “present[ed] is whether the
District Court could relinquish jurisdiction over the case
only by dismissing it without prejudice or whether the Dis-
trict Court could relinquish jurisdiction over the case by re-
manding it to state court as well.” 484 U. S., at 351. We
held that the federal court could remand as well as dismiss,
even though no statute then authorized the former action.
Id., at 357; see § 1447(c) (now flling that vacuum). Our rea-
soning, in that pre-§ 1367 era, focused on the values served
by supplemental jurisdiction, as set out in Gibbs. “[E]con-
omy, convenience, fairness, and comity,” we stated, “sup-
port[ ] giving a district court discretion to remand when
the exercise of [supplemental] jurisdiction is inappropriate.”
Cohill, 484 U. S., at 351. So when a plaintiff cuts her federal
claims, the court should have a choice about how best to get
rid of the case.
In one spot, though, the Cohill Court intimated a view on
whether the District Court also had discretion to retain the
suit. The sentence, pressed by Royal Canin, comes just be-
fore the Court's statement of the question presented, quoted
above. See Br ief for Petiti oners 10 –11, 19. It reads:
“When the single federal-law claim in the action was elimi-
nated at an early stage of the litigation, the District Court
had a powerful reason to choose not to continue to exercise

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jurisdiction.” Cohill, 484 U. S., at 351. In using the word
“choose
,” Cohill suggested that the court, though having
strong cause to dismiss or remand, likewise had authority to
decide the case.
But that slender (and somewhat backhanded) dictum can-
not make us stop in our tracks. Nowhere did Cohill analyze
why a federal court could retain jurisdiction once an amend-
ment excised all federal-law claims. Cohill simply supposed
the court could and asserted as much, without pausing to
consider the matter. And that lack of scrutiny refected the
issue's lack of importance—not in today's case of course, but
in that earlier one. As just explained, the District Court in
Cohill never thought to exercise jurisdiction after the
amendment; the issue in dispute was only how to get rid of
the action. So Cohill's view about keeping jurisdiction was
gratuitous, and no sooner noted than dropped. It supported
neither the decision's result nor its values-based reasoning.
And anyway, our own analysis is based mainly on legal au-
thorities post-dating Cohill—most notably, § 1367 and our
Rockwell decision. See supra, at 30–34, 36. Those later
materials supersede whatever Cohill presumed about exer-
cising federal jurisdiction in a case like this one. So by vir-
tue of both what it decided and when it arose, Cohill does
not matter to the question before us.
That leaves the Rockwell footnote Royal Canin cites. As
earlier explained, the body of Rockwell examines what hap-
pens in an original case when a plaintiff amends a complaint
to expunge federal claims. See supra, at 32–33, 36. The
federal court, Rockwell held, loses jurisdiction. See 549
U. S., at 473–474. But in a two-sentence footnote, the Rock-
well Court said that the opposite rule applies in removed
cases. “[W]hen a defendant removes a case to federal court
based on the presence of a federal claim,” the footnote stated,
“an amendment eliminating the original basis for federal ju-
risdiction generally does not defeat jurisdiction.” Id., at
474, n. 6. That is because “removal cases raise forum-
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42 RO
YAL CANIN U. S. A., INC. v. WULLSCHLEGER
Opinion of the Court
manipulation concerns that simply do not exist when it is the
pl
aintiff who chooses a federal forum and then pleads away
jurisdiction through amendment.” Ibid. (emphasis in origi-
nal). The footnote thus sets out exactly the rule Royal Canin
wants—and, in so doing, gives the company its best argument.
But still, the footnote is dictum, and does not control the
outcome here. Rockwell was an original federal case, not a
removed one. So the footnote's assertion of a special rule
for removed cases was outside the issue being decided—or
more colloquially put, beside the point. The statement had
no bearing on the Court's conclusion about jurisdiction in
original cases. Nor did it relate to the rationale supporting
that result. And to top it off, the footnote was itself barely
reasoned.
9
This Court has often stated that “drive-by juris-
dictional rulings”—asserting or denying jurisdiction “with-
out elaboration,” or analysis of whether anything “turn[ed]
on” the ruling—should be accorded “no precedential effect.”
Wilkins v. United States, 598 U. S. 152, 160 (2023) (quoting
Arbaugh v. Y & H Corp., 546 U. S. 500, 511, 512 (2006); alter-
ation in original; Henderson v. Shinseki, 562 U. S. 428, 437
(2011)). The admonition goes double for throwaway foot-
9
The footnote's cursory reference to “forum-manipulation concerns” fails
on multiple levels. First, and most practically, plaintiffs can usually
forum shop without any resort to amendments. Except when a statute
of limitations has expired, a plaintiff need only voluntarily dismiss her
federal suit and fle a new state-claim-only action in state court. So the
forum-manipulation beneft of the Rockwell footnote's approach to re-
moved federal-question cases is likely quite marginal. Second, that ap-
proach conficts with the one taken in the most comparable situation: when
in a removed diversity case, a plaintiff seeks a remand to state court by
means of adding a non-diverse party. As noted earlier, the rule in that
context is the standard one: Jurisdiction follows the amended pleading—
regardless of any (probably minor) forum-manipulation concerns. See
§ 1447(e); supra, at 38. Third and most important, those policy-based con-
cerns, even if signifcant, cannot trump a federal statute. And as we else-
where discuss—including in the next paragraph—§ 1367 offers no basis for
treating original and removed cases differently, as the Rockwell footnote
proposes. See supra, at 32–33.
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notes about jurisdictional issues neither raised in nor con-
ceivably
relevant to a case. We therefore need not follow
the Rockwell footnote just because it exists; our adherence
instead depends on whether it withstands analysis.
10
And it does not, for all the reasons already given. A
recap here fttingly begins with Rockwell's own core insight,
which points the opposite way. Federal courts, Rockwell
stated, “look to the amended complaint to determine juris-
diction.” 549 U. S., at 474. That rule, as earlier described,
explains a host of jurisdictional outcomes. See supra, at 35–
38. It operates in federal-question cases and diversity
cases, both to destroy and to create jurisdiction. And it can-
not give way, in a case like this one, just because the case
was removed from state to federal court. When, as here, a
complaint asserts both federal and state claims, and an
amendment strips out the federal ones, a district court's ju-
risdiction depends on § 1367. And § 1367, as earlier shown,
makes no distinction between cases beginning in federal
court and cases removed there. See supra, at 32–33. If in
the former the amendment “defeat[s] jurisdiction,” as Rock-
well rightly held, 549 U. S., at 473, then so too in the latter.
Regardless of removal, the plaintiff 's excision of her federal-
law claims deprives the district court of its authority to de-
cide the state-law claims remaining.
III
For those reasons, the District Court here should have re-
manded Wullschleger's suit to state court. The earliest ver-
sion of that suit contained federal-law claims and therefore
was properly removed to federal court. The additional
state-law claims were suffciently related to the federal ones
10
It is of course a much different thing for this Court to reach that
conclusion than for a lower court to do so. We do not at all fault any
court that relied on the Rockwell footnote to fnd jurisdiction in a case like
this one. Courts that did so simply took us at our word, in a way both
understandable and appropriate.
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Opinion of the Court
to come within that court's supplemental jurisdiction. But
when
Wullschleger amended her complaint, the jurisdic-
tional analysis also changed. Her deletion of all federal
claims deprived the District Court of federal-question juris-
diction. And once that was gone, the court's supplemental
jurisdiction over the state claims dissolved too. Wull-
schleger had reconfgured her suit to make it only about
state law. And so the suit became one for a state court.
We accordingly affrm the judgment of the Court of Ap-
peals for the Eighth Circuit.
It is so ordered.
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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