ILLINOIS TOOL WORKS INC. et al. v. INDEPENDENT INK, INC.

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28 OCTOBER TERM, 2005
Syllabus
ILLINOIS TOOL WORKS INC. et al. v.
INDEPENDENT INK, INC.
certiorari to the united states court of appeals for
the federal circuit
No. 04–1329. Argued November 29, 2005—Decided March 1, 2006
Petitioners manufacture and market printing systems that include a pat
ented printhead and ink container and unpatented ink, which they sell
to original equipment manufacturers who agree that they will purchase
ink exclusively from petitioners and that neither they nor their custom
ers will refill the patented containers with ink of any kind. Respondent
developed ink with the same chemical composition as petitioners’ ink.
After petitioner Trident’s infringement action was dismissed, respond
ent filed suit seeking a judgment of noninfringement and invalidity of
Trident’s patents on the ground that petitioners are engaged in illegal
“tying” and monopolization in violation of §§ 1 and 2 of the Sherman Act.
Granting petitioners summary judgment, the District Court rejected
respondent’s argument that petitioners necessarily have market power
as a matter of law by virtue of the patent on their printhead system,
thereby rendering the tying arrangements per se violations of the anti
trust laws. After carefully reviewing this Court’s tying-arrangements
decisions, the Federal Circuit reversed as to the § 1 claim, concluding
that it had to follow this Court’s precedents until overruled by this
Court.
Held: Because a patent does not necessarily confer market power upon
the patentee, in all cases involving a tying arrangement, the plaintiff
must prove that the defendant has market power in the tying product.
Pp. 33–46.
(a) Over the years, this Court’s strong disapproval of tying arrange
ments has substantially diminished, as the Court has moved from rely
ing on assumptions to requiring a showing of market power in the tying
product. The assumption in earlier decisions that such “arrangements
serve hardly any purpose beyond the suppression of competition,”
Standard Oil Co. of Cal. v. United States, 337 U. S. 293, 305–306, was
rejected in United States Steel Corp. v. Fortner Enterprises, Inc., 429
U. S. 610, 622 (Fortner II), and again in Jefferson Parish Hospital Dist.
No. 2 v. Hyde, 466 U. S. 2, both of which involved unpatented tying
products. Nothing in Jefferson Parish suggested a rebuttable pre
sumption of market power applicable to tying arrangements involving a
patent on the tying good. Pp. 33–38.

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29 Cite as: 547 U. S. 28 (2006)
Syllabus
(b) The presumption that a patent confers market power arose out
side the antitrust context as part of the patent misuse doctrine, and
migrated to antitrust law in International Salt Co. v. United States, 332
U. S. 392. See also Morton Salt Co. v. G. S. Suppiger Co., 314 U. S. 488;
United States v. Loew’s Inc., 371 U. S. 38. Pp. 38–40.
(c) When Congress codified the patent laws for the first time, it initi
ated the untwining of the patent misuse doctrine and antitrust jurispru
dence. At the same time that this Court’s antitrust jurisprudence con
tinued to rely on the assumption that tying arrangements generally
serve no legitimate business purpose, Congress began chipping away at
that assumption in the patent misuse context from whence it came.
Then, four years after Jefferson Parish repeated the presumption that
patents confer market power, Congress amended the Patent Code to
eliminate it in the patent misuse context. While that amendment does
not expressly refer to the antitrust laws, it invites reappraisal of Inter
national Salt’s per se rule. After considering the congressional judg
ment reflected in the amendment, this Court concludes that tying ar
rangements involving patented products should be evaluated under the
standards of cases like Fortner II and Jefferson Parish rather than the
per se rule in Morton Salt and Loew’s. Any conclusion that an arrange
ment is unlawful must be supported by proof of power in the relevant
market rather than by a mere presumption thereof. Pp. 40–43.
(d) Respondent’s alternatives to retention of the per se rule—that the
Court endorse a rebuttable presumption that patentees possess market
power when they condition the purchase of the patented product on an
agreement to buy unpatented goods exclusively from the patentee, or
differentiate between tying arrangements involving requirements ties
and other types of tying arrangements—are rejected. Pp. 43–46.
(e) Because respondent reasonably relied on this Court’s prior opin
ions in moving for summary judgment without offering evidence of the
relevant market or proving petitioners’ power within that market, re
spondent should be given a fair opportunity to develop and introduce
evidence on that issue, as well as other relevant issues, when the case
returns to the District Court. P. 46.
396 F. 3d 1342, vacated and remanded.
Stevens, J., delivered the opinion of the Court, in which all other Mem
bers joined, except Alito, J., who took no part in the consideration or
decision of the case.
Andrew J. Pincus argued the cause for petitioners. With
him on the briefs were Richard J. Favretto, Christopher J.
Kelly, Nickolai G. Levin, and Stewart S. Hudnut.

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30 ILLINOIS TOOL WORKS INC. v. INDEPENDENT INK, INC.
Counsel
Deputy Solicitor General Hungar argued the cause for
the United States as amicus curiae urging reversal. With
him on the brief were Solicitor General Clement, Acting
Assistant Attorney General Barnett, Jeffrey P. Minear,
Catherine G. O’Sullivan, Steven J. Mintz, Frances Marshall,
John M. Whealan, Cynthia C. Lynch, and Thomas Krause.
Kathleen M. Sullivan argued the cause for respondent.
With her on the briefs were Daniel H. Bromberg, Margret
M. Caruso, Elizabeth B. Wydra, and Edward F. O’Connor.*
*Briefs of amici curiae urging reversal were filed for the American
Bar Association by Robert J. Grey, Jr., Richard J. Wallis, and Kevin D.
McDonald; for the Houston Intellectual Property Law Association by
Kenneth E. Kuffner; for the Intellectual Property Law Association of Chi
cago by Edward D. Manzo, Bradford P. Lyerla, and Glen P. Belvis; for
the Intellectual Property Owners Association by Gary M. Hoffman, Ken
neth W. Brothers, and Douglas K. Norman; for the Motion Picture Associ
ation of America, Inc., et al. by Daniel G. Swanson, Julian W. Poon, Dan
iel E. Robbins, and Victor S. Perlman; for the New York Intellectual
Property Law Association by David F. Ryan; for the Patent, Trademark &
Copyright Section of the Bar Association of the District of Columbia by
David W. Long, Blair Elizabeth Taylor, and Lynn E. Eccleston; for Pfizer
Inc. by Stephen A. Stack, Jr., George G. Gordon, Rebecca P. Dick, and
Kent S. Bernard; for Verizon Communications by Richard G. Taranto,
Aaron M. Panner, and John Thorne; and for the Washington Legal Foun
dation by William C. MacLeod, Daniel J. Popeo, and David Price.
Briefs of amici curiae urging affirmance were filed for the District of
Columbia et al. by Robert J. Spagnoletti, Attorney General of the District
of Columbia, Edward E. Schwab, Deputy Attorney General, Don A. Resni
koff, Senior Assistant Attorney General, and Anika Cooper, Assistant At
torney General, by Bill Lockyer, Attorney General of California, Richard
M. Frank, Chief Deputy Attorney General, Tom Greene, Chief Assistant
Attorney General, Kathleen Foote, Senior Assistant Attorney General,
and Ann Marie Marciarille, Deputy Attorney General, and by the Attor
neys General for their respective States as follows: Terry Goddard of Ari
zona, Charles J. Crist, Jr., of Florida, Thomas J. Miller of Iowa, Charles
C. Foti, Jr., of Louisiana, J. Joseph Curran, Jr., of Maryland, Thomas F.
Reilly of Massachusetts, Jeremiah W. (Jay) Nixon of Missouri, Jim Petro
of Ohio, Paul G. Summers of Tennessee, Mark L. Shurtleff of Utah, Dar
rell V. McGraw, Jr., of West Virginia, and Patrick J. Crank of Wyoming;
for AARP et al. by Barbara Jones, Bruce Vignery, and Michael Schuster;

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31 Cite as: 547 U. S. 28 (2006)
Opinion of the Court
Justice Stevens delivered the opinion of the Court.
In Jefferson Parish Hospital Dist. No. 2 v. Hyde, 466 U. S.
2 (1984), we repeated the well-settled proposition that “if
the Government has granted the seller a patent or similar
monopoly over a product, it is fair to presume that the inabil
ity to buy the product elsewhere gives the seller market
power.” Id., at 16. This presumption of market power, ap
plicable in the antitrust context when a seller conditions its
sale of a patented product (the “tying” product) on the pur
chase of a second product (the “tied” product), has its founda
tion in the judicially created patent misuse doctrine. See
United States v. Loew’s Inc., 371 U. S. 38, 46 (1962). In 1988,
Congress substantially undermined that foundation, amend
ing the Patent Act to eliminate the market power presump
tion in patent misuse cases. See 102 Stat. 4676, codified at
35 U. S. C. § 271(d). The question presented to us today is
whether the presumption of market power in a patented
product should survive as a matter of antitrust law despite
its demise in patent law. We conclude that the mere fact
that a tying product is patented does not support such a
presumption.
I
Petitioners, Trident, Inc., and its parent, Illinois Tool
Works Inc., manufacture and market printing systems that
include three relevant components: (1) a patented piezoelec
tric impulse ink jet printhead; (2) a patented ink container,
consisting of a bottle and valved cap, which attaches to the
printhead; and (3) specially designed, but unpatented, ink.
for the American Antitrust Institute et al. by Jonathan Rubin; for the
International Imaging Technology Council et al. by Patricia Judge; for
the National Association of Theatre Owners, Inc., et al. by John T. Mitch
ell; for Barry Nalebuff et al. by Alan I. Horowitz; and for F. M. Scherer
by Parker C. Folse III and Justin A. Nelson.
Patrick J. Coyne, Kenneth M. Frankel, and William C. Rooklidge filed
a brief of amicus curiae for the American Intellectual Property Law
Association.

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32 ILLINOIS TOOL WORKS INC. v. INDEPENDENT INK, INC.
Opinion of the Court
Petitioners sell their systems to original equipment manufac
turers (OEMs) who are licensed to incorporate the print
heads and containers into printers that are in turn sold to
companies for use in printing barcodes on cartons and pack
aging materials. The OEMs agree that they will purchase
their ink exclusively from petitioners, and that neither they
nor their customers will refill the patented containers with
ink of any kind.
Respondent, Independent Ink, Inc., has developed an ink
with the same chemical composition as the ink sold by peti
tioners. After an infringement action brought by Trident
against Independent was dismissed for lack of personal juris
diction, Independent filed suit against Trident seeking a
judgment of noninfringement and invalidity of Trident’s pat
ents.1 In an amended complaint, it alleged that petitioners
are engaged in illegal tying and monopolization in violation
of §§ 1 and 2 of the Sherman Act. 15 U. S. C. §§ 1, 2.
After discovery, the District Court granted petitioners’
motion for summary judgment on the Sherman Act claims.
Independent Ink, Inc. v. Trident, Inc., 210 F. Supp. 2d 1155,
1177 (CD Cal. 2002). It rejected respondent’s submission
that petitioners “necessarily have market power in the mar
ket for the tying product as a matter of law solely by virtue
of the patent on their printhead system, thereby rendering
[the] tying arrangements per se violations of the antitrust
laws.” Id., at 1159. Finding that respondent had submit
ted no affirmative evidence defining the relevant market or
establishing petitioners’ power within it, the court concluded
that respondent could not prevail on either antitrust claim.
Id., at 1167, 1173, 1177. The parties settled their other
claims, and respondent appealed.
After a careful review of the “long history of Supreme
Court consideration of the legality of tying arrangements,”
396 F. 3d 1342, 1346 (2005), the Court of Appeals for the
1 Illinois Tool did not acquire Trident until February 19, 1999, approxi
mately six months after this action commenced.

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Opinion of the Court
Federal Circuit reversed the District Court’s decision as to
respondent’s § 1 claim, id., at 1354. Placing special reliance
on our decisions in International Salt Co. v. United States,
332 U. S. 392 (1947), and Loew’s, 371 U. S. 38, as well as our
Jefferson Parish dictum, and after taking note of the aca
demic criticism of those cases, it concluded that the “funda
mental error” in petitioners’ submission was its disregard of
“the duty of a court of appeals to follow the precedents of the
Supreme Court until the Court itself chooses to expressly
overrule them.” 396 F. 3d, at 1351. We granted certiorari
to undertake a fresh examination of the history of both the
judicial and legislative appraisals of tying arrangements.
545 U. S. 1127 (2005). Our review is informed by extensive
scholarly comment and a change in position by the adminis
trative agencies charged with enforcement of the antitrust
laws.
II
American courts first encountered tying arrangements in
the course of patent infringement litigation. See, e. g.,
Heaton-Peninsular Button-Fastener Co. v. Eureka Spe
cialty Co., 77 F. 288 (CA6 1896). Such a case came before
this Court in Henry v. A. B. Dick Co., 224 U. S. 1 (1912), in
which, as in the case we decide today, unpatented ink was
the product that was “tied” to the use of a patented product
through the use of a licensing agreement. Without com
menting on the tying arrangement, the Court held that use
of a competitor’s ink in violation of a condition of the agree
ment—that the rotary mimeograph “ ‘may be used only with
the stencil, paper, ink and other supplies made by A. B. Dick
Co.’ ”—constituted infringement of the patent on the ma
chine. Id., at 25–26. Chief Justice White dissented, ex
plaining his disagreement with the Court’s approval of a
practice that he regarded as an “attempt to increase the
scope of the monopoly granted by a patent . . . which tend[s]
to increase monopoly and to burden the public in the exercise
of their common rights.” Id., at 70. Two years later, Con

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34 ILLINOIS TOOL WORKS INC. v. INDEPENDENT INK, INC.
Opinion of the Court
gress endorsed Chief Justice White’s disapproval of tying ar
rangements, enacting § 3 of the Clayton Act. See 38 Stat.
731 (applying to “patented or unpatented” products); see also
Motion Picture Patents Co. v. Universal Film Mfg. Co., 243
U. S. 502, 517–518 (1917) (explaining that, in light of § 3 of
the Clayton Act, A. B. Dick “must be regarded as over
ruled”). And in this Court’s subsequent cases reviewing the
legality of tying arrangements we, too, embraced Chief Jus
tice White’s disapproval of those arrangements. See, e. g.,
Standard Oil Co. of Cal. v. United States, 337 U. S. 293, 305–
306 (1949); Mercoid Corp. v. Mid-Continent Investment Co.,
320 U. S. 661, 664–665 (1944).
In the years since A. B. Dick, four different rules of law
have supported challenges to tying arrangements. They
have been condemned as improper extensions of the patent
monopoly under the patent misuse doctrine, as unfair meth
ods of competition under § 5 of the Federal Trade Commis
sion Act, 15 U. S. C. § 45, as contracts tending to create a
monopoly under § 3 of the Clayton Act, 15 U. S. C. § 14, and
as contracts in restraint of trade under § 1 of the Sherman
Act.2 In all of those instances, the justification for the chal
lenge rested on either an assumption or a showing that the
defendant’s position of power in the market for the tying
product was being used to restrain competition in the market
for the tied product. As we explained in Jefferson Parish,
466 U. S., at 12, “[o]ur cases have concluded that the essential
characteristic of an invalid tying arrangement lies in the sell
er’s exploitation of its control over the tying product to force
the buyer into the purchase of a tied product that the buyer
2 See, e. g., Jefferson Parish Hospital Dist. No. 2 v. Hyde, 466 U. S. 2, 9
(1984) (Sherman Act); Times-Picayune Publishing Co. v. United States,
345 U. S. 594, 609 (1953) (Federal Trade Commission Act); International
Salt Co. v. United States, 332 U. S. 392, 395–396 (1947) (Clayton Act and
Sherman Act); Morton Salt Co. v. G. S. Suppiger Co., 314 U. S. 488, 494
(1942) (patent misuse); Motion Picture Patents Co. v. Universal Film Mfg.
Co., 243 U. S. 502, 516 (1917) (same).

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Opinion of the Court
either did not want at all, or might have preferred to pur
chase elsewhere on different terms.”
Over the years, however, this Court’s strong disapproval
of tying arrangements has substantially diminished.
Rather than relying on assumptions, in its more recent opin
ions the Court has required a showing of market power in
the tying product. Our early opinions consistently assumed
that “[t]ying arrangements serve hardly any purpose beyond
the suppression of competition.” Standard Oil Co., 337
U. S., at 305–306. In 1962, in Loew’s, 371 U. S., at 47–48, the
Court relied on this assumption despite evidence of signifi
cant competition in the market for the tying product. And
as recently as 1969, Justice Black, writing for the majority,
relied on the assumption as support for the proposition “that,
at least when certain prerequisites are met, arrangements of
this kind are illegal in and of themselves, and no specific
showing of unreasonable competitive effect is required.”
Fortner Enterprises, Inc. v. United States Steel Corp., 394
U. S. 495, 498–499 (Fortner I). Explaining the Court’s deci
sion to allow the suit to proceed to trial, he stated that “deci
sions rejecting the need for proof of truly dominant power
over the tying product have all been based on a recognition
that because tying arrangements generally serve no legiti
mate business purpose that cannot be achieved in some less
restrictive way, the presence of any appreciable restraint on
competition provides a sufficient reason for invalidating the
tie.” Id., at 503.
Reflecting a changing view of tying arrangements, four
Justices dissented in Fortner I, arguing that the challenged
“tie”—the extension of a $2 million line of credit on condition
that the borrower purchase prefabricated houses from the
defendant—might well have served a legitimate purpose.
Id., at 510 (opinion of White, J.); id., at 520 (opinion of Fortas,
J.). In his opinion, Justice White noted that promotional
tie-ins may provide “uniquely advantageous deals” to pur
chasers. Id., at 519. And Justice Fortas concluded that the

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36 ILLINOIS TOOL WORKS INC. v. INDEPENDENT INK, INC.
Opinion of the Court
arrangement was best characterized as “a sale of a single
product with the incidental provision of financing.” Id.,
at 522.
The dissenters’ view that tying arrangements may well be
procompetitive ultimately prevailed; indeed, it did so in the
very same lawsuit. After the Court remanded the suit in
Fortner I, a bench trial resulted in judgment for the plaintiff,
and the case eventually made its way back to this Court.
Upon return, we unanimously held that the plaintiff ’s failure
of proof on the issue of market power was fatal to its case—
the plaintiff had proved “nothing more than a willingness to
provide cheap financing in order to sell expensive houses.”
United States Steel Corp. v. Fortner Enterprises, Inc., 429
U. S. 610, 622 (1977) (Fortner II).
The assumption that “[t]ying arrangements serve hardly
any purpose beyond the suppression of competition,” re
jected in Fortner II, has not been endorsed in any opinion
since. Instead, it was again rejected just seven years later
in Jefferson Parish, where, as in Fortner II, we unanimously
reversed a Court of Appeals judgment holding that an al
leged tying arrangement constituted a per se violation of § 1
of the Sherman Act. 466 U. S., at 5. Like the product at
issue in the Fortner cases, the tying product in Jefferson
Parish—hospital services—was unpatented, and our holding
again rested on the conclusion that the plaintiff had failed to
prove sufficient power in the tying product market to re
strain competition in the market for the tied product—serv
ices of anesthesiologists. 466 U. S., at 28–29.
In rejecting the application of a per se rule that all tying
arrangements constitute antitrust violations, we explained:
“[W]e have condemned tying arrangements when the
seller has some special ability—usually called ‘market
power’—to force a purchaser to do something that he
would not do in a competitive market. . . .
. . . . .

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Opinion of the Court
“Per se condemnation—condemnation without inquiry
into actual market conditions—is only appropriate if the
existence of forcing is probable. Thus, application of
the per se rule focuses on the probability of anticompeti
tive consequences. . . .
“For example, if the Government has granted the seller
a patent or similar monopoly over a product, it is fair to
presume that the inability to buy the product elsewhere
gives the seller market power. United States v. Loew’s
Inc., 371 U. S., at 45–47. Any effort to enlarge the
scope of the patent monopoly by using the market power
it confers to restrain competition in the market for a
second product will undermine competition on the mer
its in that second market. Thus, the sale or lease of a
patented item on condition that the buyer make all his
purchases of a separate tied product from the patentee
is unlawful.” Id., at 13–16 (footnote omitted).
Notably, nothing in our opinion suggested a rebuttable pre
sumption of market power applicable to tying arrangements
involving a patent on the tying good. See infra, at 44;
cf. 396 F. 3d, at 1352. Instead, it described the rule that
a contract to sell a patented product on condition that the
purchaser buy unpatented goods exclusively from the pat
entee is a per se violation of § 1 of the Sherman Act.
Justice O’Connor wrote separately in Jefferson Parish,
concurring in the judgment on the ground that the case did
not involve a true tying arrangement because, in her view,
surgical services and anesthesia were not separate products.
466 U. S., at 43. In her opinion, she questioned not only the
propriety of treating any tying arrangement as a per se vio
lation of the Sherman Act, id., at 35, but also the validity
of the presumption that a patent always gives the patentee
significant market power, observing that the presumption
was actually a product of our patent misuse cases rather than

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38 ILLINOIS TOOL WORKS INC. v. INDEPENDENT INK, INC.
Opinion of the Court
our antitrust jurisprudence, id., at 37–38, n. 7. It is that
presumption, a vestige of the Court’s historical distrust of
tying arrangements, that we address squarely today.
III
Justice O’Connor was, of course, correct in her assertion
that the presumption that a patent confers market power
arose outside the antitrust context as part of the patent mis
use doctrine. That doctrine had its origins in Motion Pic
ture Patents Co. v. Universal Film Mfg. Co., 243 U. S. 502
(1917), which found no support in the patent laws for the
proposition that a patentee may “prescribe by notice
attached to a patented machine the conditions of its use and
the supplies which must be used in the operation of it, under
pain of infringement of the patent,” id., at 509. Although
Motion Picture Patents Co. simply narrowed the scope of
possible patent infringement claims, it formed the basis for
the Court’s subsequent decisions creating a patent misuse
defense to infringement claims when a patentee uses its pat
ent “as the effective means of restraining competition with
its sale of an unpatented article.” Morton Salt Co. v. G. S.
Suppiger Co., 314 U. S. 488, 490 (1942); see also, e. g., Carbice
Corp. of America v. American Patents Development Corp.,
283 U. S. 27, 31 (1931).
Without any analysis of actual market conditions, these
patent misuse decisions assumed that, by tying the purchase
of unpatented goods to the sale of the patented good, the
patentee was “restraining competition,” Morton Salt, 314
U. S., at 490, or “secur[ing] a limited monopoly of an unpat
ented material,” Mercoid, 320 U. S., at 664; see also Carbice,
283 U. S., at 31–32. In other words, these decisions pre
sumed “[t]he requisite economic power” over the tying prod
uct such that the patentee could “extend [its] economic con
trol to unpatented products.” Loew’s, 371 U. S., at 45–46.
The presumption that a patent confers market power mi
grated from patent law to antitrust law in International

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Opinion of the Court
Salt Co. v. United States, 332 U. S. 392 (1947). In that case,
we affirmed a District Court decision holding that leases of
patented machines requiring the lessees to use the defend
ant’s unpatented salt products violated § 1 of the Sherman
Act and § 3 of the Clayton Act as a matter of law. Id., at
396. Although the Court’s opinion does not discuss market
power or the patent misuse doctrine, it assumes that “[t]he
volume of business affected by these contracts cannot be said
to be insignificant or insubstantial and the tendency of the
arrangement to accomplishment of monopoly seems obvi
ous.” Ibid.
The assumption that tying contracts “ten[d] . . . to accom
plishment of monopoly” can be traced to the Government’s
brief in International Salt, which relied heavily on our ear
lier patent misuse decision in Morton Salt. The Govern
ment described Morton Salt as “present[ing] a factual situa
tion almost identical with the instant case,” and it asserted
that “although the Court in that case did not find it necessary
to decide whether the antitrust laws were violated, its lan
guage, its reasoning, and its citations indicate that the policy
underlying the decision was the same as that of the Sherman
Act.” Brief for United States in International Salt Co. v.
United States, O. T. 1947, No. 46, p. 19 (United States Brief).
Building on its assertion that International Salt was logi
cally indistinguishable from Morton Salt, the Government
argued that this Court should place tying arrangements in
volving patented products in the category of per se violations
of the Sherman Act. United States Brief 26–33.
Our opinion in International Salt clearly shows that we
accepted the Government’s invitation to import the presump
tion of market power in a patented product into our antitrust
jurisprudence. While we cited Morton Salt only for the
narrower proposition that the defendant’s patents did not
confer any right to restrain competition in unpatented salt or
afford the defendant any immunity from the antitrust laws,
International Salt, 332 U. S., at 395–396, given the fact that

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40 ILLINOIS TOOL WORKS INC. v. INDEPENDENT INK, INC.
Opinion of the Court
the defendant was selling its unpatented salt at competitive
prices, id., at 396–397, the rule adopted in International
Salt necessarily accepted the Government’s submission that
the earlier patent misuse cases supported the broader propo
sition “that this type of restraint is unlawful on its face under
the Sherman Act,” United States Brief 12.
Indeed, later in the same Term we cited International
Salt for the proposition that the license of “a patented device
on condition that unpatented materials be employed in con
junction with the patented device” is an example of a re
straint that is “illegal per se.” United States v. Columbia
Steel Co., 334 U. S. 495, 522–523, and n. 22 (1948). And in
subsequent cases we have repeatedly grounded the presump
tion of market power over a patented device in Interna
tional Salt. See, e. g., Loew’s, 371 U. S., at 45–46; Times-
Picayune Publishing Co. v. United States, 345 U. S. 594, 608
(1953); Standard Oil Co., 337 U. S., at 304.
IV
Although the patent misuse doctrine and our antitrust ju
risprudence became intertwined in International Salt, sub
sequent events initiated their untwining. This process has
ultimately led to today’s reexamination of the presumption of
per se illegality of a tying arrangement involving a patented
product, the first case since 1947 in which we have granted
review to consider the presumption’s continuing validity.
Three years before we decided International Salt, this
Court had expanded the scope of the patent misuse doctrine
to include not only supplies or materials used by a patented
device, but also tying arrangements involving a combination
patent and “unpatented material or [a] device [that] is itself
an integral part of the structure embodying the patent.”
Mercoid, 320 U. S., at 665; see also Dawson Chemical Co. v.
Rohm & Haas Co., 448 U. S. 176, 188–198 (1980) (describing
in detail Mercoid and the cases leading up to it). In reach
ing this conclusion, the Court explained that it could see “no

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difference in principle” between cases involving elements es
sential to the inventive character of the patent and elements
peripheral to it; both, in the Court’s view, were attempts
to “expan[d] the patent beyond the legitimate scope of its
monopoly.” Mercoid, 320 U. S., at 665.
Shortly thereafter, Congress codified the patent laws for
the first time. See 66 Stat. 792, codified at 35 U. S. C. § 1
et seq. (2000 ed. and Supp. III). At least partly in response
to our Mercoid decision, Congress included a provision in
its codification that excluded some conduct, such as a tying
arrangement involving the sale of a patented product tied to
an “essential” or “nonstaple” product that has no use except
as part of the patented product or method, from the scope of
the patent misuse doctrine. § 271(d); see also Dawson, 448
U. S., at 214. Thus, at the same time that our antitrust ju
risprudence continued to rely on the assumption that “tying
arrangements generally serve no legitimate business pur
pose,” Fortner I, 394 U. S., at 503, Congress began chipping
away at the assumption in the patent misuse context from
whence it came.
It is Congress’ most recent narrowing of the patent misuse
defense, however, that is directly relevant to this case. Four
years after our decision in Jefferson Parish repeated the
patent-equals-market-power presumption, 466 U. S., at 16,
Congress amended the Patent Code to eliminate that pre
sumption in the patent misuse context, 102 Stat. 4676. The
relevant provision reads:
“(d) No patent owner otherwise entitled to relief for
infringement or contributory infringement of a patent
shall be denied relief or deemed guilty of misuse or ille
gal extension of the patent right by reason of his having
done one or more of the following: . . . (5) conditioned
the license of any rights to the patent or the sale of the
patented product on the acquisition of a license to rights
in another patent or purchase of a separate product, un
less, in view of the circumstances, the patent owner has

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42 ILLINOIS TOOL WORKS INC. v. INDEPENDENT INK, INC.
Opinion of the Court
market power in the relevant market for the patent or
patented product on which the license or sale is condi
tioned.” 35 U. S. C. § 271(d)(5) (emphasis added).
The italicized clause makes it clear that Congress did not
intend the mere existence of a patent to constitute the requi
site “market power.” Indeed, fairly read, it provides that
without proof that Trident had market power in the relevant
market, its conduct at issue in this case was neither “misuse”
nor an “illegal extension of the patent right.”
While the 1988 amendment does not expressly refer to the
antitrust laws, it certainly invites a reappraisal of the per se
rule announced in International Salt.3 A rule denying a
patentee the right to enjoin an infringer is significantly less
severe than a rule that makes the conduct at issue a federal
crime punishable by up to 10 years in prison. See 15 U. S. C.
§ 1. It would be absurd to assume that Congress intended
to provide that the use of a patent that merited punishment
as a felony would not constitute “misuse.” Moreover, given
the fact that the patent misuse doctrine provided the basis
for the market power presumption, it would be anomalous
to preserve the presumption in antitrust after Congress
has eliminated its foundation. Cf. 10 P. Areeda, H.
Hovenkamp, & E. Elhauge, Antitrust Law ¶ 1737c (2d ed.
2004) (hereinafter Areeda).
After considering the congressional judgment reflected in
the 1988 amendment, we conclude that tying arrangements
involving patented products should be evaluated under the
standards applied in cases like Fortner II and Jefferson Par
ish rather than under the per se rule applied in Morton Salt
and Loew’s. While some such arrangements are still unlaw
3 While our opinions have made clear that such an invitation is not neces
sary with respect to cases arising under the Sherman Act, see State Oil
Co. v. Khan, 522 U. S. 3, 20 (1997), it is certainly sufficient to warrant
reevaluation of our precedent, id., at 21 (“[T]his Court has reconsidered
its decisions construing the Sherman Act when the theoretical underpin
nings of those decisions are called into serious question”).

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43 Cite as: 547 U. S. 28 (2006)
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ful, such as those that are the product of a true monopoly or
a marketwide conspiracy, see, e. g., United States v. Para
mount Pictures, Inc., 334 U. S. 131, 145–146 (1948), that con
clusion must be supported by proof of power in the relevant
market rather than by a mere presumption thereof.4
V
Rather than arguing that we should retain the rule of per
se illegality, respondent contends that we should endorse
a rebuttable presumption that patentees possess market
power when they condition the purchase of the patented
product on an agreement to buy unpatented goods exclu
sively from the patentee. Cf. supra, at 37–38. Respondent
recognizes that a large number of valid patents have little,
if any, commercial significance, but submits that those that
are used to impose tying arrangements on unwilling purchas
ers likely do exert significant market power. Hence, in re
spondent’s view, the presumption would have no impact on
patents of only slight value and would be justified, subject
to being rebutted by evidence offered by the patentee, in
cases in which the patent has sufficient value to enable the
patentee to insist on acceptance of the tie.
Respondent also offers a narrower alternative, suggesting
that we differentiate between tying arrangements involving
the simultaneous purchase of two products that are arguably
two components of a single product—such as the provision of
4 Our imposition of this requirement accords with the vast majority of
academic literature on the subject. See, e. g., 10 Areeda ¶ 1737a (“[T]here
is no economic basis for inferring any amount of market power from the
mere fact that the defendant holds a valid patent”); Burchfiel, Patent Mis
use and Antitrust Reform: “Blessed be the Tie?” 4 Harv. J. L. & Tech. 1,
57, and n. 340 (1991) (noting that the market power presumption has been
extensively criticized and citing sources); 1 H. Hovenkamp, M. Janis, & M.
Lemley, IP and Antitrust § 4.2a (2005 Supp.) (“[C]overage of one’s product
with an intellectual property right does not confer a monopoly”);
W. Landes & R. Posner, The Economic Structure of Intellectual Property
Law 374 (2003) (hereinafter Landes & Posner).

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44 ILLINOIS TOOL WORKS INC. v. INDEPENDENT INK, INC.
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surgical services and anesthesiology in the same operation,
Jefferson Parish, 466 U. S., at 43 (O’Connor, J., concurring in
judgment), or the licensing of one copyrighted film on condi
tion that the licensee take a package of several films in the
same transaction, Loew’s, 371 U. S. 38—and a tying arrange
ment involving the purchase of unpatented goods over a pe
riod of time, a so-called “requirements tie.” See also Brief
for Barry Nalebuff et al. as Amici Curiae. According to
respondent, we should recognize a presumption of market
power when faced with the latter type of arrangements be
cause they provide a means for charging large volume pur
chasers a higher royalty for use of the patent than small
purchasers must pay, a form of discrimination that “is strong
evidence of market power.” Brief for Respondent 27; see
generally Jefferson Parish, 466 U. S., at 15, n. 23 (discussing
price discrimination of this sort and citing sources).
The opinion that imported the “patent equals market
power” presumption into our antitrust jurisprudence, how
ever, provides no support for respondent’s proposed alter
native. In International Salt, it was the existence of the
patent on the tying product, rather than the use of a require
ments tie, that led the Court to presume market power. 332
U. S., at 395 (“The appellant’s patents confer a limited mo
nopoly of the invention they reward”). Moreover, the re
quirements tie in that case did not involve any price discrimi
nation between large volume and small volume purchasers
or evidence of noncompetitive pricing. Instead, the leases
at issue provided that if any competitor offered salt, the tied
product, at a lower price, “the lessee should be free to buy
in the open market, unless appellant would furnish the salt
at an equal price.” Id., at 396.
As we have already noted, the vast majority of academic
literature recognizes that a patent does not necessarily con
fer market power. See n. 4, supra. Similarly, while price
discrimination may provide evidence of market power, par
ticularly if buttressed by evidence that the patentee has

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45 Cite as: 547 U. S. 28 (2006)
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charged an above-market price for the tied package, see, e. g.,
10 Areeda ¶ 1769c, it is generally recognized that it also oc
curs in fully competitive markets, see, e. g., Baumol & Swan
son, The New Economy and Ubiquitous Competitive Price
Discrimination: Identifying Defensible Criteria of Market
Power, 70 Antitrust L. J. 661, 666 (2003); 9 Areeda ¶ 1711;
Landes & Posner 374–375. We are not persuaded that the
combination of these two factors should give rise to a pre
sumption of market power when neither is sufficient to do
so standing alone. Rather, the lesson to be learned from
International Salt and the academic commentary is the
same: Many tying arrangements, even those involving pat
ents and requirements ties, are fully consistent with a free,
competitive market. For this reason, we reject both re
spondent’s proposed rebuttable presumption and their nar
rower alternative.
It is no doubt the virtual consensus among economists that
has persuaded the enforcement agencies to reject the posi
tion that the Government took when it supported the per se
rule that the Court adopted in the 1940’s. See supra, at 39.
In antitrust guidelines issued jointly by the Department of
Justice and the Federal Trade Commission in 1995, the en
forcement agencies stated that in the exercise of their prose
cutorial discretion they “will not presume that a patent,
copyright, or trade secret necessarily confers market power
upon its owner.” U. S. Dept. of Justice and FTC, Antitrust
Guidelines for the Licensing of Intellectual Property § 2.2
(Apr. 6, 1995), http://www.usdoj.gov/atr/public/guidelines/
0558.pdf (as visited Feb. 24, 2006, and available in Clerk of
Court’s case file). While that choice is not binding on the
Court, it would be unusual for the Judiciary to replace the
normal rule of lenity that is applied in criminal cases with a
rule of severity for a special category of antitrust cases.
Congress, the antitrust enforcement agencies, and most
economists have all reached the conclusion that a patent does
not necessarily confer market power upon the patentee.

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46 ILLINOIS TOOL WORKS INC. v. INDEPENDENT INK, INC.
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Today, we reach the same conclusion, and therefore hold that,
in all cases involving a tying arrangement, the plaintiff must
prove that the defendant has market power in the tying
product.
VI
In this case, respondent reasonably relied on our prior
opinions in moving for summary judgment without offering
evidence defining the relevant market or proving that peti
tioners possess power within it. When the case returns to
the District Court, respondent should therefore be given a
fair opportunity to develop and introduce evidence on that
issue, as well as any other issues that are relevant to its
remaining § 1 claims. Accordingly, the judgment of the
Court of Appeals is vacated, and the case is remanded for
further proceedings consistent with this opinion.
It is so ordered.
Justice Alito took no part in the consideration or deci
sion of this case.