(Slip Opinion) OCTOBER TERM, 2013 1
Syllabus
NOTE: Where it is feasible, a syllabus (headnote) will be released, as is
being done in connection with this case, at the time the opinion is issued.
The syllabus constitutes no part of the opinion of the Court but has been
prepared by the Reporter of Decisions for the convenience of the reader.
See United States v. Detroit Timber & Lumber Co., 200 U. S. 321, 337.
SUPREME COURT OF THE UNITED STATES
Syllabus
MEDTRONIC, INC. v. MIROWSKI FAMILY VENTURES,
LLC
CERTIORARI TO THE UNITED STATES COURT OF APPEALS FOR
THE FEDERAL CIRCUIT
No. 12–1128. Argued November 5, 2013—Decided January 22, 2014
Petitioner Medtronic, Inc., designs, makes, and sells medical devices.
Respondent Mirowski Family Ventures, LLC, owns patents relating
to implantable heart stimulators. They have a licensing agreement
that permits Medtronic to practice certain Mirowski patents in ex-
change for royalty payments, and that specifies procedures to identify
products covered by the license and to resolve disputes between the
parties. Pursuant to those procedures, Mirowski notified Medtronic
of its belief that several of Medtronic’s products infringed the licensed
patents, and Medtronic then challenged that assertion of infringe-
ment in a declaratory judgment action, while accumulating disputed
royalties in an escrow account for distribution to the prevailing party.
The District Court concluded that Mirowski, as the party asserting
infringement, had the burden of proving infringement and that
Mirowski had not met that burden. The Federal Circuit disagreed.
It acknowledged that a patentee normally bears the burden of proof,
but concluded that where the patentee is a declaratory judgment de-
fendant and, like Mirowski, is foreclosed from asserting an infringe-
ment counterclaim by the continued existence of a licensing agree-
ment, the party seeking the declaratory judgment, namely Medtronic,
bears the burden of persuasion.
Held:
1. The Federal Circuit did not lack subject-matter jurisdiction in
this case. Title 28 U. S. C. §1338(a) gives federal district courts ex-
clusive jurisdiction over “any civil action arising under any Act of
Congress relating to patents,” and §1295(a)(1) gives the Federal Cir-
cuit appellate jurisdiction over any case where jurisdiction in the dis-
trict court “was based, in whole or in part, on section 1338.” The De-
2 MEDTRONIC, INC. v. MIROWSKI FAMILY VENTURES, LLC
Syllabus
claratory Judgment Act does not “extend” the federal courts’ “juris-
diction,” Skelly Oil Co. v. Phillips Petroleum Co., 339 U. S. 667, 671;
and federal courts determining declaratory judgment jurisdiction of-
ten look to the “character” of the declaratory judgment defendant’s
“threatened action,” Public Serv. Comm’n of Utah v. Wycoff Co., 344
U. S. 237, 248, i.e., whether the defendant’s hypothetical “coercive ac-
tion” “would necessarily present a federal question,” Franchise Tax
Bd. of Cal. v. Construction Laborers Vacation Trust for Southern Cal.,
463 U. S. 1, 19. Here, if Medtronic had acted consistent with the un-
derstanding of its rights that it seeks to establish through the declar-
atory judgment suit (by ceasing to pay royalties), Mirowski could
terminate the license and bring a suit for infringement. That suit
would arise under federal patent law because “patent law creates the
cause of action.” Christianson v. Colt Industries Operating Corp., 486
U. S. 800, 809. Thus, this declaratory judgment action, which avoids
that hypothetical threatened action, also “arises under” federal pa-
tent law. See, e.g., Security-First Nat. Bank of Los Angeles v. Fran-
chise Tax Bd. of Cal., 368 U. S. 3, 19. Pp. 4–6.
2. When a licensee seeks a declaratory judgment against a patentee
that its products do not infringe the licensed patent, the patentee
bears the burden of persuasion on the issue of infringement. Pp. 6–
11.
(a) This conclusion is strongly supported by three settled legal
propositions: First, a patentee ordinarily bears the burden of proving
infringement, see, e.g., Agawam Co. v. Jordan, 7 Wall. 583, 609; sec-
ond, the “operation of the Declaratory Judgment Act” is only “proce-
dural,” Aetna Life Ins. Co. v. Haworth, 300 U. S. 227, 240, leaving
“substantive rights unchanged,” Beacon Theatres, Inc. v. Westover,
359 U. S. 500, 509; and third, “the burden of proof” is a “ ‘substantive’
aspect of a claim,” Raleigh v. Illinois Dept. of Revenue, 530 U. S. 15,
20–21. Practical considerations lead to the same conclusion. Shifting
the burden based on the form of the action could create postlitigation
uncertainty about a patent’s scope. It may also create unnecessary
complexity by compelling a licensee to prove a negative. Finally,
burden shifting is difficult to reconcile with the Declaratory Judg-
ment Act’s purpose of ameliorating the “dilemma” posed by “putting”
one challenging a patent’s scope “to the choice between abandoning
his rights or risking” suit, MedImmune, Inc. v. Genentech, Inc., 549
U. S. 118, 129. To the extent that the Federal Circuit’s burden shift-
ing rule makes the declaratory judgment procedure disadvantageous,
that rule recreates the dilemma that the Declaratory Judgment Act
sought to avoid. Pp. 6–9.
(b) Several arguments to the contrary are unconvincing. First,
Schaffer v. Weast, 546 U. S. 49, which noted the “ordinary default
Cite as: 571 U. S. ____ (2014) 3
Syllabus
rule” that “plaintiffs” have the “risk of failing to prove their claims,”
does not support the Federal Circuit’s conclusion. Schaffer was not a
declaratory judgment case, and it described exceptions to its basic
burden of proof rule. For reasons explained in this case, declaratory
judgment suits like this one are an exception to Schaffer’s default
rule. Second, the fact that the Federal Circuit limited its holding to
the circumstance where a license forecloses an infringement counter-
claim by a patentee cannot, by itself, show that the holding is legally
justified. Third, contrary to one amicus’ concern that this Court’s
holding will permit licensees to force patent holders into full-blown
infringement litigation, such litigation can occur only when there is a
genuine and sufficiently “immedia[te]” dispute about a patent’s valid-
ity or application, MedImmune, supra, at 127. Here, Mirowski set
this dispute in motion by accusing Medtronic of infringement, and
there is no convincing reason why burden of proof law should favor
the patentee. General considerations relating to the public interest
in maintaining a well-functioning patent system are, at most, in bal-
ance, and do not favor changing the ordinary burden of proof rule.
Pp. 9–11.
695 F. 3d 1266, reversed and remanded.
BREYER, J., delivered the opinion for a unanimous Court.
Cite as: 571 U. S. ____ (2014) 1
Opinion of the Court
NOTICE: This opinion is subject to formal revision before publication in the
preliminary print of the United States Reports. Readers are requested to
notify the Reporter of Decisions, Supreme Court of the United States, Wash-
ington, D. C. 20543, of any typographical or other formal errors, in order
that corrections may be made before the preliminary print goes to press.
SUPREME COURT OF THE UNITED STATES
_________________
No. 12–1128
_________________
MEDTRONIC, INC., PETITIONER v. MIROWSKI
FAMILY VENTURES, LLC
ON WRIT OF CERTIORARI TO THE UNITED STATES COURT OF
APPEALS FOR THE FEDERAL CIRCUIT
[January 22, 2014]
JUSTICE BREYER delivered the opinion of the Court.
A patentee ordinarily bears the burden of proving in-
fringement. Agawam Co. v. Jordan, 7 Wall. 583, 609
(1869). This case asks us to decide whether the burden of
proof shifts when the patentee is a defendant in a declara-
tory judgment action, and the plaintiff (the potential
infringer) seeks a judgment that he does not infringe the
patent. We hold that, when a licensee seeks a declaratory
judgment against a patentee to establish that there is no
infringement, the burden of proving infringement remains
with the patentee. We reverse the Federal Circuit’s de-
termination to the contrary.
I
A
We set forth a simplified version of the facts. The par-
ties are Medtronic, Inc., a firm that (among other things)
designs, makes, and sells medical devices, and Mirowski
Family Ventures, LLC, a firm that owns patents relating
to implantable heart stimulators. In 1991 Medtronic and
Mirowski entered into an agreement permitting Medtronic
to practice certain Mirowski patents in exchange for royalty
2 MEDTRONIC, INC. v. MIROWSKI FAMILY VENTURES, LLC
Opinion of the Court
payments.
In less simplified form: Mirowski entered into a license
agreement with Eli Lilly & Co., which then sublicensed
the Mirowski patents to Medtronic. Guidant Corp. is Eli
Lilly’s successor in interest. For present purposes we shall
ignore Eli Lilly, Guidant, and other parties on Mirowski’s
side, using “Mirowski” to refer to any and all of them.
The 1991 agreement also provided that, if Mirowski
gave notice to Medtronic that a new Medtronic product
“infringe[d]” a Mirowski patent, Medtronic had a choice.
App. 13. Medtronic could simply “cure the nonpayment of
royalties.” Ibid. Or it could pay royalties and, at the same
time, “challenge” the “assertion of infringement of any of
the Mirowski patents through a Declaratory Judgment
action.” Ibid. Medtronic, of course, might just ignore the
agreement and decide not to pay royalties at all, in which
case Mirowski would have “the right to terminate the
[l]icense,” ibid., and, if it wished, bring an infringement
action.
In 2006 the parties entered into a further agreement
that slightly modified the procedure for resolving disputes.
If Medtronic, having received “timely written notice of
infringement,” chose to pursue a declaratory judgment
action “challenging infringement,” it could “accumulate
disputed royalties” in an escrow account. Id., at 24, 27.
The prevailing party in the declaratory judgment action
would receive the royalties. Id., at 28.
In 2007 the parties found themselves in the midst of
an “infringement” dispute. Mirowski gave Medtronic notice
that it believed seven new Medtronic products violated
various claims contained in two of its patents (related to
devices that cause the heart’s ventricles to contract simul-
taneously as the heart beats). Medtronic thought that its
products did not infringe Mirowski’s patents, either be-
cause the products fell outside the scope of the patent
claims or because the patents were invalid.
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Opinion of the Court
B
In 2007 Medtronic brought this declaratory judgment
action in Federal District Court in Delaware. It sought a
declaration that its products did not infringe Mirowski’s
patents and that the patents were invalid. But, as its
agreement with Mirowski provided, Medtronic paid all the
relevant royalties into an escrow account.
The District Court recognized that Mirowski was the
defendant in the action. But it nonetheless believed that
Mirowski, “[a]s the part[y] asserting infringement,” bore
the burden of proving infringement. Medtronic, Inc. v.
Boston Scientific Corp., 777 F. Supp. 2d 750, 766 (Del.
2011); see Under Sea Industries, Inc. v. Dacor Corp., 833
F. 2d 1551, 1557 (CA Fed. 1987) (“The burden always is on
the patentee to show infringement”). After a bench trial,
the court found that Mirowski had not proved infringe-
ment, either directly or under the doctrine of equivalents.
And since Mirowski, the patentee, bore the burden of
proof, it lost. 777 F. Supp. 2d, at 767–770.
The Court of Appeals for the Federal Circuit considered
the burden of proof question, and it came to the opposite
conclusion. It held that Medtronic, the declaratory judg-
ment plaintiff, bore the burden. It acknowledged that
normally the patentee, not the accused infringer, bears the
burden of proving infringement, and that the burden
normally will not “shift” even when the patentee is “a
counterclaiming defendant in a declaratory judgment
action.” 695 F. 3d 1266, 1272 (2012). Nonetheless, the
Court of Appeals believed that a different rule applies
where that patentee is a declaratory judgment defendant
and, like Mirowski, that patentee/defendant is “foreclosed”
from asserting an “infringement counterclaim” by the
“continued existence of a license.” Id., at 1274. In that
case, the Court of Appeals held, the party “seeking a de-
claratory judgment of noninfringement,” namely Medtronic,
“bears the burden of persuasion.” Ibid.
4 MEDTRONIC, INC. v. MIROWSKI FAMILY VENTURES, LLC
Opinion of the Court
Medtronic sought certiorari, asking us to review the
Federal Circuit’s burden of proof rule. In light of the
importance of burdens of proof in patent litigation, we
granted the petition.
II
We begin with a jurisdictional matter. An amicus
claims that we must vacate the Federal Circuit’s decision
because that court lacked subject-matter jurisdiction.
Amicus agrees with the parties that 28 U. S. C. §1338(a)
gives federal district courts exclusive jurisdiction over
“any civil action arising under any Act of Congress relat-
ing to patents” (emphasis added). Moreover, the version of
§1295(a)(1) governing this appeal gives the Federal Circuit
exclusive appellate jurisdiction over any case where juris-
diction in the district court “was based, in whole or in
part, on section 1338.” But, amicus says, in determining
whether this case is a “civil action arising under” an “Act
of Congress relating to patents,” we must look to the na-
ture of the action that the declaratory judgment defend-
ant, namely the patentee, Mirowski, could have brought in
the absence of a declaratory judgment. And that action,
amicus adds (in its most significant argument against
jurisdiction), would not be a patent infringement action
but, rather, an action for damages for breach of contract,
namely an action for breach of the Mirowski-Medtronic
licensing contract, in which patent infringement is the
central issue. See Brief for Tessera Technologies, Inc., as
Amicus Curiae 2–3.
We agree with amicus that the Declaratory Judgment
Act does not “extend” the “jurisdiction” of the federal
courts. Skelly Oil Co. v. Phillips Petroleum Co., 339 U. S.
667, 671 (1950). We also agree that federal courts, when
determining declaratory judgment jurisdiction, often look
to the “character of the threatened action.” Public Serv.
Comm’n of Utah v. Wycoff Co., 344 U. S. 237, 248 (1952).
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Opinion of the Court
That is to say, they ask whether “a coercive action”
brought by “the declaratory judgment defendant” (here
Mirowski) “would necessarily present a federal question.”
Franchise Tax Bd. of Cal. v. Construction Laborers Vaca-
tion Trust for Southern Cal., 463 U. S. 1, 19 (1983).
But we do not agree with amicus’ characterization of
the “threatened” or “coercive” action that Mirowski might
have brought. The patent licensing agreement specifies
that, if Medtronic stops paying royalties, Mirowski can
terminate the contract and bring an ordinary patent in-
fringement action. Such an action would arise under
federal patent law because “federal patent law creates the
cause of action.” Christianson v. Colt Industries Operating
Corp., 486 U. S. 800, 809 (1988).
Amicus says that an infringement suit would be un-
likely. But that is not the relevant question. The relevant
question concerns the nature of the threatened action in
the absence of the declaratory judgment suit. Medtronic
believes—and seeks to establish in this declaratory judg-
ment suit—that it does not owe royalties because its prod-
ucts are noninfringing. If Medtronic were to act on that
belief (by not paying royalties and not bringing a declara-
tory judgment action), Mirowski could terminate the
license and bring an ordinary federal patent law action for
infringement. See Brief for Respondent 48 (acknowledg-
ing that if Medtronic had “chosen not to pay the royalties
. . . it would have subjected itself to a suit for infringe-
ment”). Consequently this declaratory judgment action,
which avoids that threatened action, also “arises under”
federal patent law. See Franchise Tax Bd., supra, at 19;
Wycoff Co., supra, at 248. See also MedImmune, Inc. v.
Genentech, Inc., 549 U. S. 118, 128 (2007) (concluding
that Article III’s case-or-controversy requirement was satis-
fied where a patent licensee faced the threat of suit if it
ceased making payments under a license agreement, not-
withstanding that the licensee’s continued royalty pay-
6 MEDTRONIC, INC. v. MIROWSKI FAMILY VENTURES, LLC
Opinion of the Court
ments rendered the prospect of such a suit “remote, if not
nonexistent”).
For this reason we believe that the hypothetical threat-
ened action is properly characterized as an action “arising
under an Act of Congress relating to patents.” 28 U. S. C.
§1338(a).
III
We now turn to the question presented. A patent li-
censee paying royalties into an escrow account under a pat-
ent licensing agreement seeks a declaratory judgment that
some of its products are not covered by or do not infringe
the patent, and that it therefore does not owe royalties for
those products. In that suit, who bears the burden of
proof, or, to be more precise, the burden of persuasion?
Must the patentee prove infringement or must the licensee
prove noninfringement? In our view, the burden of per-
suasion is with the patentee, just as it would be had the
patentee brought an infringement suit.
A
Simple legal logic, resting upon settled case law, strongly
supports our conclusion. It is well established that the
burden of proving infringement generally rests upon the
patentee. See, e.g., Imhaeuser v. Buerk, 101 U. S. 647, 662
(1880) (“[T]he burden to prove infringement never shifts
[to the alleged infringer] if the charge is denied in the plea
or answer”); Agawam Co., 7 Wall., at 609 (“Infringement is
an affirmative allegation made by the complainant, and
the burden of proving it is upon him . . .”). See also Under
Sea Industries, 833 F. 2d, at 1557 (“The burden always is
on the patentee to show infringement”); 5B Chisum
§18.06[1][a], at 18–1180 (2007) (“[T]he burden of proof on
factual issues relating to infringement rests upon the
patent owner”).
We have long considered “the operation of the Declara-
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Opinion of the Court
tory Judgment Act” to be only “procedural,” Aetna Life Ins.
Co. v. Haworth, 300 U. S. 227, 240 (1937), leaving “sub-
stantive rights unchanged,” Beacon Theatres, Inc. v.
Westover, 359 U. S. 500, 509 (1959). See also Vaden v.
Discover Bank, 556 U. S. 49, 70, n. 19 (2009); Skelly Oil
Co., 339 U. S., at 674 (noting the “limited procedural
purpose of the Declaratory Judgment Act”).
And we have held that “the burden of proof ” is a “ ‘sub-
stantive’ aspect of a claim.” Raleigh v. Illinois Dept. of
Revenue, 530 U. S. 15, 20–21 (2000); Director, Office of
Workers’ Compensation Programs v. Greenwich Collieries,
512 U. S. 267, 271 (1994) (“[T]he assignment of the burden
of proof is a rule of substantive law . . .”); Garrett v. Moore-
McCormack Co., 317 U. S. 239, 249 (1942) (“[T]he burden
of proof . . . [is] part of the very substance of [the plain-
tiff ’s] claim and cannot be considered a mere incident of a
form of procedure”).
Taken together these three legal propositions indicate
that, in a licensee’s declaratory judgment action, the
burden of proving infringement should remain with the
patentee.
Several practical considerations lead to the same con-
clusion. To shift the burden depending upon the form of
the action could create postlitigation uncertainty about the
scope of the patent. Suppose the evidence is inconclusive,
and an alleged infringer loses his declaratory judgment
action because he failed to prove noninfringement. The
alleged infringer, or others, might continue to engage in
the same allegedly infringing behavior, leaving it to the
patentee to bring an infringement action. If the burden
shifts, the patentee might lose that action because, the
evidence being inconclusive, he failed to prove infringe-
ment. So, both sides might lose as to infringement,
leaving the infringement question undecided, creating
uncertainty among the parties and others who seek to
know just what products and processes they are free to use.
8 MEDTRONIC, INC. v. MIROWSKI FAMILY VENTURES, LLC
Opinion of the Court
The example is not fanciful. The Restatement (Second)
of Judgments says that relitigation of an issue (say, in-
fringement) decided in one suit “is not precluded” in a
subsequent suit where the burden of persuasion “has
shifted” from the “party against whom preclusion is sought
. . . to his adversary.” Restatement (Second) of Judgments
§28(4) (1980). Rather, the
“[f ]ailure of one party to carry the burden of persua-
sion on an issue should not establish the issue in favor
of an adversary who otherwise would have the burden
of persuasion on that issue in later litigation.” 18 C.
Wright, A. Miller, & E. Cooper, Federal Practice and
Procedure §4422, p. 592 (2d ed. 2002).
Thus the declaratory judgment suit in the example above
would have failed to achieve its object: to provide “an
immediate and definitive determination of the legal rights
of the parties.” Aetna, supra, at 241.
Moreover, to shift the burden can, at least on occasion,
create unnecessary complexity by making it difficult for
the licensee to understand upon just what theory the
patentee’s infringement claim rests. A complex patent can
contain many pages of claims and limitations. A patent
holder is in a better position than an alleged infringer to
know, and to be able to point out, just where, how, and
why a product (or process) infringes a claim of that patent.
Until he does so, however, the alleged infringer may have
to work in the dark, seeking, in his declaratory judg-
ment complaint, to negate every conceivable infringement
theory.
Finally burden shifting here is difficult to reconcile with
a basic purpose of the Declaratory Judgment Act. In
MedImmune, Inc. v. Genentech, Inc., a case that similarly
concerned a patent licensee that brought a declaratory
judgment action after the patentee accused it of infringe-
ment, we wrote that the “ ‘very purpose’ ” of that Act is to
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Opinion of the Court
“ ‘ameliorate’ ” the “dilemma” posed by “putting” one who
challenges a patent’s scope “to the choice between aban-
doning his rights or risking” suit. 549 U. S., at 129 (quot-
ing Abbott Laboratories v. Gardner, 387 U. S. 136, 152
(1967)). In the absence of the declaratory judgment proce-
dure, Medtronic would face the precise dilemma that
MedImmune describes. Either Medtronic would have to
abandon its right to challenge the scope of Mirowski’s
patents, or it would have to stop paying royalties, risk
losing an ordinary patent infringement lawsuit, and
thereby risk liability for treble damages and attorney’s
fees as well as injunctive relief. See 35 U. S. C. §§283–285
(providing for injunctive relief, treble damages, and—in
“exceptional cases”—attorney’s fees as remedies for patent
infringement). As in MedImmune, the declaratory judg-
ment action rescues Medtronic from this dilemma.
The Federal Circuit’s burden shifting rule does not
deprive Medtronic of the right to seek a declaratory judg-
ment. But it does create a significant obstacle to use of that
action. It makes the declaratory judgment procedure—
compared to, say, just refusing to pay royalties—dis-
advantageous. To that extent it recreates the dilemma
that the Declaratory Judgment Act sought to avoid. As we
have made clear (and as we explain below), we are un-
aware of any strong reason for creating that obstacle.
B
We are not convinced by the arguments raised to the
contrary. First, the Federal Circuit thought it had found
support in a recent case of this Court, Schaffer v. Weast,
546 U. S. 49 (2005). In that case we referred to the “ordi-
nary default rule” as placing upon the “plaintiffs” the “risk
of failing to prove their claims.” Id., at 56. We added that
that is because the plaintiffs are normally the parties
“seeking relief.” Id., at 58. And Medtronic, not Mirowski,
is the declaratory judgment “plaintif[f ]” here.
10 MEDTRONIC, INC. v. MIROWSKI FAMILY VENTURES, LLC
Opinion of the Court
Schaffer, however, was not a declaratory judgment case.
And Schaffer described exceptions to its basic burden of
proof rule. E.g., id., at 57 (when an element of a claim
“can fairly be characterized as [an] affirmative defens[e],”
the burden of proof “may be shifted to [the] defendants”);
id., at 60 (“ ‘[T]he ordinary rule, based on considerations
of fairness, does not place the burden upon a litigant of
establishing facts peculiarly within the knowledge of his
adversary’ ” (quoting United States v. New York, N. H. &
H. R. Co., 355 U. S. 253, 256, n. 5 (1957)). For the reasons
we have set forth in Part III–A, supra, declaratory judg-
ment suits like the one at issue here constitute a further
exception to the basic rule Schaffer described.
Second, the Federal Circuit emphasized that its holding
applied only in “the limited circumstance when an in-
fringement counterclaim by a patentee is foreclosed by the
continued existence of a license.” 695 F. 3d, at 1274. The
fact that the Federal Circuit’s opinion is limited, how-
ever, does not support its conclusion. The “limited cir-
cumstance” it described is often present when a patent
licensee faces an ordinary but disputed claim of infringe-
ment. And that “circumstance” is virtually identical to
MedImmune, where we found a declaratory judgment action
constitutionally permissible. In any event, the fact that a
rule’s scope is limited cannot, by itself, show that the rule
is legally justified.
Third, an amicus supporting Mirowski fears that our
holding, unlike the Federal Circuit’s rule, will “burden . . .
patent owners” by permitting “a licensee . . . —at its sole
discretion—[to] force the patentee into full-blown patent-
infringement litigation.” Brief for Intellectual Property
Owners Association as Amicus Curiae 9. The short an-
swer to this argument, however, is that litigation can
occur only in the presence of a genuine dispute, “ ‘of suffi-
cient immediacy and reality,’ ” about the patent’s validity
or its application. MedImmune, supra, at 127 (quoting
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Opinion of the Court
Maryland Casualty Co. v. Pacific Coal & Oil Co., 312 U. S.
270, 273 (1941)). Indeed, it was Mirowski that set the
present dispute in motion by accusing Medtronic of in-
fringement. And in such an instance, we see no convinc-
ing reason why burden of proof law should favor the
patentee.
The public interest, of course, favors the maintenance of
a well-functioning patent system. But the “public” also
has a “paramount interest in seeing that patent monopo-
lies . . . are kept within their legitimate scope.” Precision
Instrument Mfg. Co. v. Automotive Maintenance Machin-
ery Co., 324 U. S. 806, 816 (1945). A patentee “should
not be . . . allowed to exact royalties for the use of an idea
. . . that is beyond the scope of the patent monopoly
granted.” Blonder-Tongue Laboratories, Inc. v. University of
Ill. Foundation, 402 U. S. 313, 349–350 (1971). And
“[l]icensees may often be the only individuals with enough
economic incentive” to litigate questions of a patent’s
scope. Lear, Inc. v. Adkins, 395 U. S. 653, 670 (1969). The
general public interest considerations are, at most, in
balance. They do not favor a change in the ordinary rule
imposing the burden of proving infringement upon the
patentee.
For these reasons the judgment of the Federal Circuit is
reversed, and the case is remanded for further proceedings
consistent with this opinion.
It is so ordered.