                                     PUBLISHED

                      UNITED STATES COURT OF APPEALS
                          FOR THE FOURTH CIRCUIT


                                      No. 17-1715


KRISTIANA TWEED BURRELL, individually and as Administratrix of the
Estate of Ariel Grace Burrell; TRAVIS BURRELL,

                    Plaintiffs - Appellants,

                                         v.

BAYER CORPORATION, an Indiana corporation; BAYER HEALTHCARE
LLC, a Delaware corporation; CHRISTOPHER FORD WILLIAMS; STACY D.
TRAVIS, Dr.; BILTMORE OB-GYN, P.A.; BAYER ESSURE INC., f/k/a
Conceptus, Inc., a Delaware corporation; BAYER HEALTHCARE
PHARMACEUTICALS, INC., a Delaware corporation,

                    Defendants - Appellees.


Appeal from the United States District Court for the Western District of North Carolina,
at Asheville. Max O. Cogburn, Jr., District Judge. (1:17-cv-00031-MOC-DCK)


Argued: October 30, 2018                                      Decided: March 14, 2019


Before FLOYD and HARRIS, Circuit Judges, and Donald C. COGGINS, Jr., United
States District Judge for the District of South Carolina, sitting by designation.


Vacated and remanded by published opinion. Judge Harris wrote the opinion, in which
Judge Floyd and Judge Coggins joined.


ARGUED: Tejinder Singh, GOLDSTEIN & RUSSELL, P.C., Washington, D.C., for
Appellants. Erika L. Maley, SIDLEY AUSTIN LLP, Washington, D.C., for Appellees.
ON BRIEF: George Fleming, Rand P. Nolen, Jessica Kasischke, Sylvia Davidow,
FLEMING, NOLEN & JEZ, L.L.P., Houston, Texas; Thomas C. Goldstein,
GOLDSTEIN & RUSSELL, P.C., Bethesda, Maryland, for Appellants. Jonathan F.
Cohn, Virginia A. Seitz, Christopher A. Eiswerth, Morgan Branch, SIDLEY AUSTIN
LLP, Washington, D.C., for Appellees.




                                      2
PAMELA HARRIS, Circuit Judge:

       Kristiana Tweed Burrell and her husband filed suit against Bayer in connection

with a female sterilization device known as Essure, alleging that Burrell suffered a

stillbirth and then underwent a hysterectomy due to complications from the device. The

Burrells commenced this action in North Carolina state court, seeking damages for

violations of North Carolina tort and products liability law.

       The issue we confront in this appeal is not the merits of the Burrells’ claims, but

whether those claims should be heard in state or federal court. According to Bayer, this

is a federal case:    Although the Burrells seek relief under state law, their claims

necessarily implicate significant questions regarding Bayer’s compliance with federal

regulations and thus give rise to federal question jurisdiction under 28 U.S.C. § 1331.

We disagree. As the Supreme Court has emphasized, § 1331 confers federal jurisdiction

over state-law causes of action only in a “special and small” class of cases. Empire

HealthChoice Assurance, Inc. v. McVeigh, 547 U.S. 677, 699 (2006).              Because the

Burrells’ state-law action against Bayer does not fall within that special class, it should be

decided by North Carolina’s courts. We therefore vacate the district court’s contrary

judgment and direct that the case be remanded to state court.



                                              I.

                                             A.

       The crux of Bayer’s argument for federal question jurisdiction is that because

Essure is regulated by the federal government, the Burrells’ suit regarding Essure will

                                              3
require the resolution of important federal-law questions. We begin by briefly describing

the federal laws and regulations that govern Essure, to provide necessary context for

Bayer’s position and the proceedings in this case.

       Essure is a permanent female contraceptive consisting of metal coils, known as

“micro-inserts,” inserted into a woman’s fallopian tubes.       Once released through a

disposable delivery system, the micro-inserts expand and anchor in the fallopian tubes,

causing fibrous tissue growth that blocks the tubes and prevents pregnancy.

       Essure is regulated by the Food and Drug Administration (“FDA”) as a Class III

medical device, under the 1976 Medical Device Amendments to the Federal Food, Drug,

and Cosmetic Act (“FDCA” or “Act”). Class III devices are subject to the most stringent

oversight under the Act, see 21 U.S.C. § 360c(a)(1)(C), and a novel Class III device like

Essure cannot be distributed until it receives premarket approval from the FDA, id.

§ 360e. Following premarket approval, a manufacturer cannot amend the device design

without FDA sign-off, can make only limited changes to the device’s labeling, and must

submit to the FDA information regarding adverse events related to the device, 1 among

other requirements. See id. §§ 360e(d)(5)(A)(i), 360i(a); 21 C.F.R. § 814.39(a), (d).




       1
          Specifically, a manufacturer like Bayer must report to the FDA any instance in
which its approved device “may have caused or contributed to a death or serious injury,”
and any malfunction that would “be likely to cause or contribute to a death or serious
injury if the malfunction were to recur.” 21 U.S.C. § 360i(a)(1)(A)–(B).


                                            4
       The Act does not establish a private right of action to enforce these requirements

under federal law. With respect to state-law remedies, the Act includes an express

preemption provision, prohibiting states from imposing requirements on premarket-

approved Class III medical devices – like Essure – that are “different from, or in addition

to” federal requirements. 21 U.S.C. § 360k(a). That leaves room, as the Supreme Court

has explained, for state-law remedies for violations of common-law duties that “parallel”

federal regulatory requirements. Medtronic, Inc. v. Lohr, 518 U.S. 470, 495 (1996); see

also Riegel v. Medtronic, Inc., 552 U.S. 312, 330 (2008). A claim that a Class III device

“violated state tort law notwithstanding compliance with the relevant federal

requirements” would be preempted under § 360k(a), because it seeks to impose

“addition[al]” state-law requirements on the federally-approved device. Riegel, 552 U.S.

at 330 (emphasis added). But a claim “premised on a violation of FDA regulations” is

not preempted, because “the state duties in such a case ‘parallel,’ rather than add to,

federal requirements.” Id. (emphasis added).

       Essure received premarket approval from the FDA in 2002. Accordingly, the

Burrells may proceed against Bayer under North Carolina law consistent with § 360k(a)

to the extent (and only to the extent) that the state-law duties on which they rely

“parallel” the federal requirements that apply to Essure. What relief is available under

North Carolina law is of course a question of state and not federal law.

                                            B.

       Kristiana Tweed Burrell received an Essure implantation in December 2013.

According to Burrell, tests performed in the ensuing months found that the device was

                                             5
causing only a partial blockage of her left fallopian tube, and thus failing to provide

contraceptive protection.

       On June 5, 2015, Burrell discovered that she was pregnant when she felt fetal

movement. Two days later, she experienced abdominal pain and vaginal bleeding, and

went into premature labor at home. Burrell was admitted to the hospital, where her baby

was delivered stillborn at an estimated 24 to 27 weeks. Burrell was diagnosed with

placental abruption, a serious pregnancy complication in which the placenta prematurely

separates from the uterus. Subsequent doctor visits confirmed that Burrell’s Essure

implant had failed and was eroding through the left fallopian tube. To remove the device,

Burrell then was required to undergo a total hysterectomy – that is, a surgical procedure

to remove her uterus.

       In December 2016, Burrell and her husband filed separate lawsuits in North

Carolina state court against the Bayer Corporation and related defendants (collectively,

“Bayer”). 2   The lawsuits, later consolidated, seek damages for personal injuries,

emotional distress, and wrongful death under various state-law causes of action, relying

primarily on four core allegations. First and most prominently, the Burrells allege that

Bayer failed to disclose to the medical community or the FDA numerous adverse events

similar to those they experienced, depriving them of proper warning about Essure’s risks.


       2
           The Burrells also sued the obstetrician-gynecologist and medical practice that
performed the implantation, alleging medical malpractice under North Carolina law. The
district court ultimately declined to exercise supplemental jurisdiction over that claim, so
it is not addressed or affected by our decision today.


                                             6
Second, they assert that Bayer failed to update its labeling and marketing materials to

reflect these risks, further depriving them of adequate warning. Third, they claim that

Bayer sold Essure implants with manufacturing defects, suggesting that one of these

defects may have been present in Burrell’s implant and caused her injuries. And fourth,

they allege that Bayer did not adequately train doctors, including Burrell’s obstetrician-

gynecologist, on the implantation procedure, despite informing the public otherwise.

       That conduct, according to the complaints, violated state law in multiple respects.

Specifically, the complaints assert the following causes of action against Bayer under

North Carolina law: that Bayer was negligent and breached its duty to warn the Burrells

of known dangers regarding Essure; that Essure was unreasonably dangerous in violation

of state products liability law; that Bayer breached both express and implied warranties;

and that Bayer engaged in fraud and unfair or deceptive trade practices. In anticipation of

a federal preemption defense, as outlined above, the complaints also allege that Bayer

violated numerous federal regulatory requirements that purportedly parallel Bayer’s

duties under state law.

                                             C.

       The jurisdictional question at issue in this appeal arose when Bayer removed the

Burrells’ actions to federal court, invoking 28 U.S.C. § 1441. Under that provision,

Bayer was entitled to remove the case only if the Burrells’ state-law claims could have

been brought in federal court originally, based on some independent source of federal

jurisdiction. See Merrell Dow Pharm. Inc. v. Thompson, 478 U.S. 804, 808 (1986).

Because the parties to this case are not diverse for purposes of diversity jurisdiction under

                                             7
28 U.S.C. § 1332, Bayer’s notice of removal identified one and only one basis for federal

jurisdiction: 28 U.S.C. § 1331, conferring what is known as federal question jurisdiction

over civil actions “arising under” federal law.

       Cases generally are deemed to “arise under” federal law when it is federal law, not

state law, that creates the cause of action. See Merrell Dow, 478 U.S. at 808. But Bayer

argued that the Burrells’ case falls within an exception to that general rule because their

state-law claims necessarily raise substantial federal-law questions.        The Burrells’

complaints, Bayer noted, contained multiple references to federal regulatory requirements

allegedly violated by Bayer.     And because the Burrells’ state-law claims would be

preempted unless Bayer had violated parallel federal duties, their right to relief

necessarily required resolution of those federal-law questions.      Moreover, given the

FDA’s extensive oversight of Essure, whether Bayer had lived up to its regulatory

obligations was a matter of sufficient federal importance that it warranted adjudication in

a federal forum.

       The district court agreed, denying the Burrells’ motion to remand the case to state

court and retaining jurisdiction under § 1331. The court began by laying out the “four-

part test” that governs whether a lawsuit based on state-law claims gives rise to federal

question jurisdiction: To come within § 1331, the case must feature a state-law claim that

(1) “necessarily raise[s]” a federal issue, and that federal issue must be “(2) actually

disputed, (3) substantial, and (4) capable of resolution in federal court without disrupting

the federal-state balance approved by Congress.” J.A. 1130 (quoting Gunn v. Minton,

568 U.S. 251, 258 (2013)).

                                             8
       As to the first two prongs – whether the Burrells’ state-law claims “necessarily

raise[]” disputed federal issues – the court essentially adopted Bayer’s argument. The

Burrells’ complaints, the court reasoned, are “replete with references to the FDA” and

allegations that Bayer failed to comply with its federal regulatory duties. J.A. 1131. As a

result of the Act’s express preemption provision, the court continued, the Burrells cannot

succeed on their state-law claims unless they can show that Bayer in fact deviated from

those federal requirements. “Accordingly, [the federal regulations governing Essure] are

implicated here and in dispute.” J.A. 1133.

       The court relied again on the Act’s preemptive effect under the latter two prongs

of the analysis. Because “state law is generally pre-empted” under § 360k(a), the court

determined, “[i]t does not upset the federal-state balance to allow [manufacturers of]

federally-approved medical devices to be sued . . . in federal court.” J.A. 1136. And

because what is at issue is “federal oversight of Class III medical device products,” the

district court further reasoned, the dispute as to federal law is “substantial.” Id.

       Having retained jurisdiction, the court two months later granted Bayer’s motion to

dismiss the Burrells’ case, largely on preemption grounds. See Burrell v. Bayer Corp.,

260 F. Supp. 3d 485 (W.D.N.C. 2017). The Burrells timely appealed, challenging both

the district court’s exercise of jurisdiction and the dismissal of their case on the merits.



                                              II.

       We begin and end with the district court’s jurisdictional holding. “Subject matter

jurisdiction defines a court’s power to adjudicate cases or controversies – its adjudicatory

                                               9
authority – and without it, a court can only decide that it does not have jurisdiction.”

United States v. Wilson, 699 F.3d 789, 793 (4th Cir. 2012). If the Burrells’ case “was not

properly removed, because it was not within the original jurisdiction of the United States

district courts,” then the district court was without jurisdiction to rule on its merits and

instead was required to remand the action to state court. Franchise Tax Bd. of Cal. v.

Constr. Laborers Vacation Trust, 463 U.S. 1, 8 (1983) (citing 28 U.S.C. § 1447(c)). We

review the district court’s jurisdictional holding de novo, Mulcahey v. Columbia Organic

Chems. Co., 29 F.3d 148, 151 (4th Cir. 1994), and conclude that it was in error.

Accordingly, this case must be remanded to state court for proceedings on the merits.

                                             A.

       Under 28 U.S.C. § 1331, federal courts have federal question jurisdiction over “all

civil actions arising under the Constitution, laws, or treaties of the United States.” In the

“vast majority of cases,” that means suits “in which federal law creates the cause of

action.” Merrell Dow, 478 U.S. at 808; see also Dixon v. Coburg Dairy, Inc., 369 F.3d

811, 816 (4th Cir. 2004) (en banc). This case is about the exception to that rule – the

“slim category” of cases, Gunn, 568 U.S. at 258, in which state law supplies the cause of

action but federal courts have jurisdiction under § 1331 because “the plaintiff’s right to

relief necessarily depends on resolution of a substantial question of federal law,”

Franchise Tax Bd., 463 U.S. at 28.

       As the Supreme Court has emphasized, courts are to be cautious in exercising

jurisdiction of this type, which lies at “the outer reaches of § 1331.” Merrell Dow, 478

U.S. at 810. The “mere presence of a federal issue in a state cause of action” is not

                                             10
enough to confer jurisdiction.      Id. at 813.     If it were, then innumerable claims

traditionally heard in state court would be funneled to federal court instead, raising

“serious federal-state conflicts.” Franchise Tax Bd., 463 U.S. at 10. To avoid those

conflicts and ensure that state-law claims only rarely give rise to § 1331 jurisdiction, the

Supreme Court has established the four-pronged test outlined by the district court in this

case: The federal question must be “necessarily raise[d]” and “actually disputed” by the

parties. Grable & Sons Metal Prods. v. Darue Eng’g & Mfg., 545 U.S. 308, 314 (2005).

It also must be “substantial,” id., meaning that its resolution is “importan[t] . . . to the

federal system as a whole,” Gunn, 568 U.S. at 260. And, finally, the federal system must

be able to hear the issue “without disturbing any congressionally approved balance of

federal and state judicial responsibilities.” Grable, 545 U.S. at 314.

       Applying those factors, a substantial majority of district courts to consider the

issue have held that state-law tort and products liability claims regarding medical devices

regulated by the FDA – including Bayer’s Essure – do not give rise to federal question

jurisdiction. Some have concluded that these state-law claims do not “necessarily raise”

federal-law questions. See, e.g., Sangimino v. Bayer Corp., No. 17-cv-01488-WHA,

2017 WL 2500904, at *3 (N.D. Cal. June 9, 2017) (involving Essure); Vieira v. Mentor

Worldwide, LLC, No. 2:18-cv-06502-AB, 2018 WL 4275998, at *5 (C.D. Cal. Sept. 7,

2018). Others have held that any federal issues that might be “necessarily raised” are not

“substantial” or cannot be heard in federal court without disrupting the proper federal-

state balance. See, e.g., Steed v. Bos. Sci. Corp., No. 4:17-cv-00824, 2017 WL 2984854,



                                             11
at *3 (N.D. Ohio July 12, 2017) (collecting cases); Waitz v. Yoon, No. 1:14-cv-2875-

MHC, 2015 WL 11511577, at *3 (N.D. Ga. June 30, 2015) (collecting cases).

       We agree with those courts. As the party seeking removal, Bayer bears the burden

of establishing federal jurisdiction, in a context in which we “strictly construe”

jurisdictional limits because of the “significant federalism concerns” that attend the

removal of cases from state court to federal court. Mulcahey, 29 F.3d at 151. We

question whether Bayer can establish that the Burrells’ state-law claims “necessarily

raise” federal-law issues under § 1331. And in any event, Bayer cannot establish that the

federal questions it identifies should be heard in federal rather than state court under the

third and fourth prongs of the § 1331 analysis.

                                             B.

       We start with the requirement that a plaintiff’s claims, though brought under state

law, “necessarily raise” federal-law questions. As we explain, the theory adopted by the

district court – that the Burrells’ state-law claims necessarily raise federal preemption

questions under § 360k(a) – is not a basis for § 1331 jurisdiction. Whether there might be

some other theory on which the Burrells’ complaints necessarily raise federal questions is

a closer question that we need not decide in this case.

                                             1.

       As described above, the district court agreed with Bayer that the “necessarily

raised” standard was satisfied here because the Burrells’ complaints allege numerous

violations of federal regulatory requirements that parallel state-law duties.        Under

§ 360k(a)’s express preemption provision, the court reasoned, the Burrells’ right to relief

                                             12
on their state-law claims turns on whether Bayer breached parallel federal requirements,

and so the question of Bayer’s compliance with federal law is necessarily implicated by

the Burrells’ action.

       On this point, Bayer and the district court are fundamentally mistaken. A federal

question is “necessarily raised” for purposes of § 1331 only if it is a “necessary element

of one of the well-pleaded state claims.” Franchise Tax Bd., 463 U.S. at 13. It is not

enough that federal law becomes relevant by virtue of a “defense . . . anticipated in the

plaintiff’s complaint.” Id. at 14; accord Pressl v. Appalachian Power Co., 842 F.3d 299,

302 (4th Cir. 2016). As the district court’s own reasoning makes clear, that is precisely

what is happening in this case: The complaints are “replete” with federal-law references

because the Burrells are anticipating a preemption defense by Bayer and explaining how

their state-law claims parallel federal standards and thus fall outside § 360k(a)’s express

preemption provision. That is not grounds for § 1331 jurisdiction: “[A] case may not be

removed to federal court [under § 1331] on the basis of a federal defense, including the

defense of preemption, even if the defense is anticipated in the plaintiff’s complaint, and

even if both parties admit that the defense is the only question truly at issue in the case.”

Pinney v. Nokia, Inc., 402 F.3d 430, 443 (4th Cir. 2005) (quoting Franchise Tax Bd., 463

U.S. at 14).

       We applied exactly that principle in Pinney, finding that § 1331 did not confer

federal question jurisdiction over state tort and products liability claims regarding a

wireless telephone subject to extensive federal regulation. 402 F.3d at 442–49. It did not

matter, we held, whether the plaintiffs’ state-law claims could be decided without

                                             13
resolving whether they were preempted by federal law. Id. at 446. Under the well-

pleaded complaint rule, we explained, our § 1331 inquiry is limited to the plaintiff’s

statement of his own claim; we do not consider affirmative defenses that might be

anticipated in the complaint. Id. at 443, 445–46; see also Flying Pigs, LLC v. RRAJ

Franchising, LLC, 757 F.3d 177, 181 (4th Cir. 2014) (“well-pleaded complaint rule”

confines § 1331 inquiry to the “plaintiff’s statement of his own claim . . . unaided by

anything alleged in anticipation or avoidance of defenses which it is thought the

defendant may interpose” (internal quotation marks omitted)). Because the elements of

the Pinney plaintiffs’ state-law claims could be established without resort to federal law,

the defendant’s preemption defense did not “necessarily” raise a federal-law question

cognizable under § 1331: A “lurking question of federal law” in the form of “the

affirmative defense of preemption . . . does not make the claims into ones arising under

federal law.” 402 F.3d at 446.

       The same rule applies here. As in Pinney, we look only to the necessary elements

of the Burrells’ causes of action to determine whether they raise federal questions under

§ 1331. And for most of their theories of liability, it is clear and undisputed that the

Burrells can establish all the necessary elements entirely independently of federal law.

One example will suffice: In North Carolina, a claim for inadequate warning is made out

if “the manufacturer or seller acted unreasonably in failing to provide such warning;” the

“failure to provide adequate warning or instruction was a proximate cause of the harm for

which damages are sought;” and either “the product, without an adequate warning or

instruction, created an unreasonably dangerous condition” or the manufacturer “failed to

                                            14
take reasonable steps to give adequate warning” after becoming aware “that the product

posed a substantial risk of harm to a reasonably foreseeable user.”               N.C. Gen.

Stat. § 99B-5(a). Each of those elements raises purely state-law questions; none requires

a showing that Bayer violated federal law. Cf. Pinney, 402 F.3d at 446–47 (analyzing

elements of plaintiffs’ causes of action).         Whether Bayer provided FDA-approved

warnings may be relevant to Bayer’s preemption defense – but, again, “a preemption

defense ‘that raises a federal question is inadequate to confer federal jurisdiction.’” Id. at

446 (quoting Merrell Dow, 478 U.S. at 808). 3

                                              2.

       In the face of this clear precedent, Bayer now advances a new rationale for treating

the Burrells’ state-law action as one that necessarily raises questions of federal law.

Among the Burrells’ many theories of recovery, Bayer argues, are a few in which

violations of federal law are alleged not in anticipation of a preemption defense, but as

actual predicates for state-law liability.   For one, Bayer emphasizes, the complaints

repeatedly assert Bayer’s alleged failure to report adverse events to the FDA – a duty


       3
          It is well established, of course, that preemption is an affirmative defense. The
burden of establishing preemption, in other words, is on the defendant; plaintiffs like the
Burrells are not required to establish, nor to allege in their complaints, that their claims
are not preempted. Great-W. Life & Annuity Ins. Co. v. Info. Sys. & Networks Corp., 523
F.3d 266, 270 (4th Cir. 2008); see also Metro. Life Ins. Co. v. Taylor, 481 U.S. 58, 63
(1987) (“Federal pre-emption is ordinarily a . . . defense to the plaintiff’s suit. As a
defense, it does not appear on the face of a well-pleaded complaint, and, therefore, does
not authorize removal to federal court.”). To the extent that Bayer or the district court
may be understood to suggest the opposite – that non-preemption is somehow an element
of the Burrells’ state-law causes of action – they are in error.


                                             15
created solely by federal law, according to Bayer – in connection with multiple causes of

action. And both parties focus on the complaints’ assertion that Bayer was negligent per

se – that is, that Bayer’s alleged violations of federal law in and of themselves establish

negligence under North Carolina tort law.         In instances like these, Bayer urges, a

violation of federal law becomes a “necessary element” of the plaintiffs’ own state-law

claims, satisfying the well-pleaded complaint rule and giving rise to federal question

jurisdiction under § 1331.

       We may assume for purposes of this appeal that the premise of Bayer’s argument

is correct, and that the assertions it has identified – including the “fraud on the FDA”

allegation – in fact turn on questions of federal law. 4 Even so, there is another hurdle for

Bayer: A federal question is not “necessarily” raised under § 1331 unless it is essential to

resolving a state-law claim, meaning that “every legal theory supporting the claim

requires the resolution of a federal issue.” Dixon, 369 F.3d at 816. If, on the other hand,

each of the Burrells’ claims is supported by a state-law theory that does not require

recourse to federal law, then that claim does not “arise under” federal law – even if the

Burrells have alleged an alternative federal-law theory that also could prove liability. See


       4
          The Burrells acknowledge that their negligence per se theory is predicated on
establishing violations of federal law. But it is less clear that the same is true of the
“fraud on the FDA” allegation. In Stengel v. Medtronic Inc., 704 F.3d 1224, 1232–33
(2013) (en banc), the Ninth Circuit considered very similar state-law tort claims
predicated on an alleged failure to report adverse events to the FDA, and concluded that
the plaintiffs’ claims were based on an independent state-law duty to warn that could be
satisfied by reports to the FDA, running parallel to the defendant’s duties under federal
law.


                                             16
Pressl, 842 F.3d at 304; Flying Pigs, 757 F.3d at 182. In other words, so long as “even

one theory” for each of the Burrells’ claims does not require “interpretation of federal

law,” resolution of the federal-law question is not necessary to the disposition of their

case. Pressl, 842 F.3d at 304.

       According to Bayer, the complaints’ allegations of negligence per se and fraud on

the FDA should be treated as distinct claims, each requiring resolution of federal-law

questions and thus satisfying the “necessarily raised” prong. But the Burrells see it

differently, insisting that allegations like negligence per se and fraud on the FDA are

merely alternative theories of liability, and that they can recover on each of their actual

claims – negligence, products liability, and the like – on an alternative state-law theory

that in no way implicates federal law. See In re Lipitor Antitrust Litig., 855 F.3d 126,

144–45 (3d Cir. 2017) (distinguishing between “claims” and “theories” for purposes of

“arising under” jurisdiction). For that reason, the Burrells urge, answers to federal-law

questions are not essential to any of their claims.

       Under the well-pleaded complaint rule, the Burrells are the “master[s] of the[ir]

claim,” Pinney, 402 F.3d at 442 (internal quotation marks omitted), entitled to structure

their complaint in the way they think most advantageous. And as the Burrells point out,

each of the assertions identified by Bayer is subsumed in their complaints under a cause

of action that also includes alternative state-law theories of liability. Faced with a similar

complaint in another Essure case, the court in Sangimino v. Bayer agreed with the

plaintiffs, holding that allegations in their complaint predicated on Bayer’s alleged failure

to follow FDA requirements were “alternative federal-law-based theories” for state-law

                                             17
claims that also were “supported by . . . independent” state-law theories. 2017 WL

2500904, at *2 (internal quotation marks omitted).          We took a similar approach in

Mulcahey v. Columbia Organic, treating an allegation of negligence per se based on a

violation of federal regulations as “only an alternative theory of liability” under the

plaintiffs’ negligence cause of action. 29 F.3d at 153. Because the plaintiffs “might still

be entitled to recover under an alternative” state-law theory, we held, § 1331 did not

confer federal question jurisdiction. Id.; see also In re Lipitor, 855 F.3d at 147 (rejecting

“divide-and-conquer approach to ‘arising under’ jurisdiction” that would treat alternative

theories or factual allegations as separate claims).

       At the same time, we think this question is not entirely free from doubt. The

distinction between a stand-alone claim and a theory of liability is not always clear. And

because that distinction may turn on the precise way in which a complaint is drafted,

there is no bright-line rule in the precedent to guide our analysis – nor a prospect that we

could provide one through a line-by-line parsing of these particular complaints.

Ultimately, we need not decide in this appeal whether the Burrells’ complaints assert any

distinct claim that can be resolved only by reference to federal law. Instead, for the

reasons we turn to now, we conclude that Bayer in any event cannot establish federal

question jurisdiction under the third and fourth prongs of the § 1331 analysis.

                                              C.

       Under the standard set out by the Supreme Court for identifying the narrow class

of state-law actions that will give rise to federal question jurisdiction, it is not enough that

a plaintiff’s state-law claim necessarily raises some contested federal issue. That federal

                                              18
issue also must be “substantial,” indicating a “serious federal interest” in sending the case

to a federal forum; and even if it is, exercising federal jurisdiction must be “consistent

with congressional judgment about the sound division of labor between state and federal

courts.” Grable, 545 U.S. at 313. Any doubt on that score is resolved against Bayer,

which bears the burden of establishing jurisdiction, especially given the significant

federalism implications of removing a state-law action from state court. See Mulcahey,

29 F.3d at 148 (“If federal jurisdiction is doubtful, a remand is necessary.”). We find that

Bayer cannot meet its burden under this part of the § 1331 inquiry.

                                              1.

       Our analysis is framed by two Supreme Court cases, one identifying the kind of

state-law action that will not give rise to jurisdiction under this standard, and one

identifying the kind of action that will. First, in Merrell Dow v. Thompson, the Supreme

Court held that § 1331 did not confer federal question jurisdiction over an action much

like this one, in which the plaintiffs alleged state-law products liability claims regarding a

pharmaceutical regulated under the FDCA – the same federal statute that governs Essure

– and incorporated the federal standard into a cause of action for negligence per se. 478

U.S. at 817. “[T]he mere presence of a federal issue in a state cause of action does not

automatically confer federal-question jurisdiction,” the Court explained. Id. at 813. The

Court found it highly significant that Congress had not provided a federal private cause of

action for FDCA violations, suggesting a congressional determination that the “presence

of the federal issue as an element of the state tort” is “insufficiently ‘substantial’ to confer

federal-question jurisdiction.” Id. at 814. An alleged “powerful federal interest” in

                                              19
uniform interpretation of the FDCA, a federal statute, did not change the Court’s

calculus; a need for uniformity is properly addressed through preemption, not by opening

the doors to federal jurisdiction. Id. at 815–16.

       In the second case, Grable & Sons v. Darue, the Supreme Court applied Merrell

Dow and this time found that a state quiet-title claim did present a removable federal

question under § 1331, where resolution of the claim depended on the interpretation of a

notice standard in federal tax law. 545 U.S. at 314–15. That federal question, the Court

held, was “sufficiently real and substantial” because it required establishing the meaning

of a federal statute. Id. at 316 (internal quotation marks omitted). And importantly,

because “it will be the rare state title case that raises” an interpretive question under

federal law, removing such cases to federal court “will portend only a microscopic effect

on the federal-state division of labor.” Id. at 315. That was to be contrasted, the Court

explained, with the state-law claims at issue in Merrell Dow: Because plaintiffs so

commonly incorporate an alleged violation of federal standards into “garden variety state

tort law” complaints regarding federally regulated products, a “general rule of exercising

federal jurisdiction” in those cases would “herald[] a potentially enormous shift of

traditionally state cases into federal courts.” Id. at 318–19.

                                              2.

       From those book-end cases – and subsequent Supreme Court decisions applying

them – we can derive most of the principles that govern this case. First, as Grable makes

clear, there is a high bar for treating a federal issue as sufficiently “substantial” under the

third prong of the § 1331 analysis. The “classic example,” according to Grable, is a

                                              20
federal question regarding the constitutionality or construction of a federal statute, id. at

312–13; in Grable itself, the question was whether “the action of a federal agency” was

“compatib[le] with a federal statute,” the resolution of which “would be controlling in

numerous other cases,” Empire HealthChoice, 547 U.S. at 700 (describing Grable). As a

practical matter, a “substantial” question generally will involve a “pure issue of law,”

rather than being “fact-bound and situation-specific,” id. at 700–01, because the crux of

what makes a question “substantial” for § 1331 purposes is that it is “importan[t] . . . to

the federal system as a whole,” and not just to the “particular parties in the immediate

suit,” Gunn, 568 U.S. at 260.

       The federal questions implicated by the Burrells’ assertions of negligence per se

and fraud on the FDA – assuming, as we do, that they are necessarily raised – bear none

of these hallmarks of “substantiality.” At bottom, what they require are fact-intensive

inquiries into Bayer’s compliance with certain FDA requirements: whether Bayer timely

notified the FDA of alleged adverse events concerning Essure, manufactured Burrell’s

implant consistent with the FDA-approved design, and properly disseminated FDA-

authorized labels and warnings. The Burrells do not allege, by contrast, that the Act is

unconstitutional in any of its relevant applications, or that the FDA has exceeded its

statutory authority or misapplied its own regulations in its oversight of Essure. Their

claims are purely “backward-looking,” id. at 261, limited to monetary relief for Bayer’s

alleged past non-compliance with federal safety standards. Though the resolution of

those questions undoubtedly is important to Bayer – and to the Burrells – it is not

“substantial in the relevant sense,” because it lacks “importance more generally” to the

                                             21
federal regulatory regime and to other medical-device manufacturers. Id. at 260–61; see

also Steed, 2017 WL 2984854, at *4 (remanding state-law action against medical-device

manufacturer to state court because the federal issue in the case, while “significant to the

parties, . . . does not transcend the parties, affect the government’s operations, or

challenge federal law in a manner evidencing importance of the issue to the federal

system as a whole”); Patterson v. Bayer Corp. LLC, No. 6:17-cv-00048-KKC, 2018 WL

1906102, at *3 (E.D. Ky. Apr. 23, 2018) (rejecting Bayer’s argument that “applying the

federal requirements [at] issue [regarding Essure], particularly reporting requirements,

. . . will implicate broader or more substantial federal issues”).

       Bayer argues, however, that fact-specific questions regarding its federal

compliance should be treated as “substantial” in this case because they recur in numerous

other cases involving Essure, so that exercising federal jurisdiction would help to ensure

uniformity.    But the Supreme Court considered and rejected that very argument in

Merrell Dow, holding that even a strong interest in uniformity of results is not enough to

make a federal question “substantial” so that it may be heard in federal court. 478 U.S. at

815–16. State courts are fully capable of resolving federal issues that arise in connection

with the state claims before them, and the “possibility that a state court will incorrectly

resolve a state claim is not, by itself, enough to trigger the federal courts’ . . . jurisdiction,

even if the potential error finds its root in a misunderstanding of [federal] law.” Gunn,

568 U.S. at 263; see also Merrell Dow, 478 U.S. at 816 (noting that uniformity concerns

are “considerably mitigated” by Supreme Court authority to review decisions of federal

issues in state-court actions).

                                               22
       Finally, to the extent Bayer or the district court suggests that the “substantiality”

prong is satisfied because the question of federal preemption is a “substantial” one, this is

mistaken. It may be true that adjudication of Bayer’s federal preemption defense will be

important to the outcome of the Burrells’ action, and even that the precedent it sets might

affect non-parties to this case. But as we have explained already, a federal preemption

defense, no matter how substantial, is not grounds for § 1331 jurisdiction. See Franchise

Tax Bd., 463 U.S. at 14 (holding that a case may not be removed to federal court on the

basis of a preemption defense even where “both parties admit that the defense is the only

question truly at issue in the case”). The substantiality inquiry applies only to those

federal issues that are necessarily raised by a complaint, and that category does not

include affirmative preemption defenses.

                                             3.

       Bayer’s failure to satisfy the substantiality prong of the § 1331 analysis by itself

necessitates a remand to state court.      See Pressl, 842 F.3d at 303 (§ 1331 confers

jurisdiction only “if a case meets all four requirements” of the Supreme Court’s four-

prong standard (citing Gunn, 568 U.S. at 258)). But it follows from the substantiality

analysis – and, again, from Merrell Dow and Grable – that Bayer also cannot make the

showing required under the fourth prong: that removal of this state-law case and the

multitude of cases just like it would be consistent with the “congressionally approved

balance of federal and state judicial responsibilities.” See Grable, 545 U.S. at 314.

       Indeed, the Supreme Court effectively held as much in Grable, in the course of

explaining why a state quiet-title action, unlike Merrell Dow’s state tort action, could be

                                             23
removed to federal court without upsetting the federal-state judicial balance. Quiet-title

actions, the Court observed, only rarely raise substantial questions of federal law, and so

they can be removed to federal court when they do without “materially affect[ing] . . . the

normal currents of litigation.” Id. at 319. “Garden variety state tort” actions involving

federally regulated products, on the other hand – like Merrell Dow and this case – very

commonly incorporate allegations of federal regulatory violations, often by way of

negligence per se claims. Id. at 318. Exercising federal jurisdiction over all of those

actions, as Merrell Dow concluded, would risk enormous disruption to the division of

judicial labor, with a “tremendous number of cases” shunted from state to federal court.

Id. (explaining Merrell Dow).

       And there is no indication that Congress intended to divert a multitude of fact-

intensive, state-law suits against medical-device manufacturers to federal court. Again,

Grable’s understanding of Merrell Dow is controlling.         In Merrell Dow, the Court

explained in Grable, the Court relied on two factors to assess Congress’s intent with

respect to state-law actions involving pharmaceuticals regulated under the FDCA:

Congress had not created a private right of action – a direct pathway to federal court – for

FDCA violations, and Congress also had not preempted state-law remedies for violations.

That combination, the Court concluded, was “an important clue to Congress’s conception

of the scope of jurisdiction” under § 1331, because it evinced an intent to have such cases




                                            24
heard by state courts. Id. (describing Merrell Dow); see also Merrell Dow, 478 U.S. at

812. 5

         The same is true here. Like the pharmaceuticals at issue in Merrell Dow, Bayer’s

Essure, a medical device, is regulated under the FDCA.           For medical devices, like

pharmaceuticals, Congress declined to create a federal cause of action for violations of

the Act, while allowing states to “provid[e] a damages remedy for claims premised on a

violation of FDA regulations” when those regulations parallel state-law duties. Riegel,

552 U.S. at 330. Just as in Merrell Dow, it would “flout, or at least undermine” this

congressionally-approved enforcement regime, in which injured parties may seek redress

under state law and only under state law, to insist that those cases must be heard in

federal courts if defendants choose to remove them. 478 U.S. at 812; see also Grable,

545 U.S. at 319 (“Merrell Dow thought it improbable that the Congress, having made no

provision for a federal cause of action, would have meant to welcome any state-law tort




         5
         The Court in Grable took the opportunity to clarify that Merrell Dow does not
establish a “bright-line rule” that there can be no jurisdiction in contexts in which
Congress has declined to provide a private right of action for enforcement of a federal
statute. 545 U.S. at 317. Instead, “Merrell Dow should be read in its entirety as treating
the absence of a federal private right of action as evidence relevant to, but not dispositive
of, the sensitive judgments about congressional intent that § 1331 requires.” Id. at 318
(internal quotation marks omitted). Adopting Bayer’s argument, the district court relied
heavily on this doctrinal refinement in its decision, emphasizing that “the fact that there is
no private right of action under the FDCA is not dispositive.” J.A. 1136. But Grable
casts no doubt on Merrell Dow’s outcome or principal reasoning, and for the reasons
given above, Grable’s analysis of Merrell Dow demonstrates that Bayer cannot establish
§ 1331 jurisdiction under the final two prongs of the analysis.


                                             25
case implicating federal law solely because the violation of the federal statute is said to

[establish negligence per se] under state law.” (internal quotation marks omitted)).

       The district court, in concluding otherwise, reasoned that because Congress

provided for exacting regulation of medical devices by the FDA and expressly preempted

“different” or “addition[al]” state requirements, see 21 U.S.C. § 360k(a), the exercise of

federal jurisdiction would be consistent with congressional intent. But that conflates the

question of preemption with the question of jurisdiction.        Congress’s desire that a

uniform substantive standard apply to FDA-regulated medical devices is a question of

preemption law, distinct from congressional intent to vest jurisdiction over such claims in

a state or federal forum. See Merrell Dow, 478 U.S. at 816. And North Carolina’s courts

are fully capable of applying federal preemption law, ensuring that the Burrells may

recover, consistent with § 360k(a), only for violations of state-law duties that parallel

rather than add to Bayer’s federal regulatory obligations.



                                            III.

       The Burrells’ action does not fall within the small class of cases in which state-law

claims may be deemed to arise under federal law for purposes of conferring federal

jurisdiction under § 1331. Accordingly, the district court erred in denying the Burrells’

motion to remand their case to state court and deciding Bayer’s motion to dismiss. We

therefore vacate the judgments of the district court and remand with instructions that the

action be remanded to North Carolina state court.

                                                             VACATED AND REMANDED

                                            26
