(Slip Opinion) OCTOBER TERM, 2006 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 

MICROSOFT CORP. v. AT&T CORP. 

CERTIORARI TO THE UNITED STATES COURT OF APPEALS FOR 

THE FEDERAL CIRCUIT 

No. 05–1056. Argued February 21, 2007—Decided April 30, 2007 

It is the general rule under United States patent law that no infringement occurs when a patented product is made and sold in another 

country. There is an exception. Section 271(f) of the Patent Act,

adopted in 1984, provides that infringement does occur when one 

“suppl[ies] . . . from the United States,” for “combination” abroad, a

patented invention’s “components.” 35 U. S. C. §271(f)(1). This case 

concerns the applicability of §271(f) to computer software first sent

from the United States to a foreign manufacturer on a master disk,

or by electronic transmission, then copied by the foreign recipient for 

installation on computers made and sold abroad. 

AT&T holds a patent on a computer used to digitally encode and

compress recorded speech. Microsoft’s Windows operating system 

has the potential to infringe that patent because Windows incorporates software code that, when installed, enables a computer to process speech in the manner claimed by the patent. Microsoft sells Windows to foreign manufacturers who install the software onto the 

computers they sell. Microsoft sends each manufacturer a master 

version of Windows, either on a disk or via encrypted electronic 

transmission, which the manufacturer uses to generate copies. Those 

copies, not the master version sent by Microsoft, are installed on the

foreign manufacturer’s computers. The foreign-made computers are 

then sold to users abroad. 

AT&T filed an infringement suit charging Microsoft with liability

for the foreign installations of Windows. By sending Windows to foreign manufacturers, AT&T contended, Microsoft “supplie[d] . . . from

the United States,” for “combination” abroad, “components” of

AT&T’s patented speech-processing computer, and, accordingly, was

liable under §271(f). Microsoft responded that unincorporated soft-
2 MICROSOFT CORP. v. AT&T CORP. 

Syllabus 

ware, because it is intangible information, cannot be typed a “component” of an invention under §271(f). Microsoft also urged that the

foreign-generated copies of Windows actually installed abroad were

not “supplie[d] . . . from the United States.” Rejecting these responses, the District Court held Microsoft liable under §271(f), and a 

divided Federal Circuit panel affirmed. 

Held: Because Microsoft does not export from the United States the 

copies of Windows installed on the foreign-made computers in question, Microsoft does not “suppl[y] . . . from the United States” “components” of those computers, and therefore is not liable under §271(f)

as currently written. Pp. 7–19.

(a) A copy of Windows, not Windows in the abstract, qualifies as a

“component” under §271(f). Section 271(f) attaches liability to the 

supply abroad of the “components of a patented invention, where 

such components are uncombined in whole or in part, in such manner 

as to actively induce the combination of such components.” §271(f)(1)

(emphasis added). The provision thus applies only to “such components” as are combined to form the “patented invention” at issue—

here, AT&T’s speech-processing computer. Until expressed as a computer-readable “copy,” e.g., on a CD-ROM, Windows—indeed any

software detached from an activating medium—remains uncombinable. It cannot be inserted into a CD-ROM drive or downloaded 

from the Internet; it cannot be installed or executed on a computer.

Abstract software code is an idea without physical embodiment, and 

as such, it does not match §271(f)’s categorization: “components” 

amenable to “combination.” Windows abstracted from a tangible copy

no doubt is information—a detailed set of instructions—and thus 

might be compared to a blueprint (or anything else containing design

information). A blueprint may contain precise instructions for the

construction and combination of the components of a patented device,

but it is not itself a combinable component. 

The fact that it is easy to encode software’s instructions onto a computer-readable medium does not counsel a different answer. The 

copy-producing step is what renders software a usable, combinable 

part of a computer; easy or not, the extra step is essential. Moreover, 

many tools may be used easily and inexpensively to generate the 

parts of a device. Those tools are not, however, “components” of the

devices in which the parts are incorporated, at least not under any

ordinary understanding of the term “component.” Congress might 

have included within §271(f)’s compass, for example, not only a patented invention’s combinable “components,” but also “information, instructions, or tools from which those components readily may be generated.” It did not. Pp. 9–12. 

(b) Microsoft did not “suppl[y] . . . from the United States” the for-
Cite as: 550 U. S. ____ (2007) 3 

Syllabus 

eign-made copies of Windows installed on the computers here involved. Under a conventional reading of §271(f)’s text, those copies

were “supplie[d]” from outside the United States. The Federal Circuit majority concluded, however, that for software components, the

act of copying is subsumed in the act of supplying. A master sent 

abroad, the majority observed, differs not at all from exact copies,

generated easily, inexpensively, and swiftly from the master. Hence, 

sending a single copy of software abroad with the intent that it be

replicated invokes §271(f) liability for the foreign-made copies. Judge

Rader, dissenting, noted that “supplying” is ordinarily understood to 

mean an activity separate and distinct from any subsequent “copying,” “replicating,” or “reproducing”—in effect, manufacturing. He 

further observed that the only true difference between software components and physical components of other patented inventions is that

copies of software are easier to make and transport. But nothing in 

§271(f)’s text, Judge Rader maintained, renders ease of copying a 

relevant, no less decisive, factor in triggering liability for infringement. The Court agrees. Under §271(f)’s text, the very components 

supplied from the United States, and not foreign-made copies thereof, 

trigger liability when combined abroad to form the patented invention at issue. While copying software abroad is indeed easy and inexpensive, the same can be said of other items, such as keys copied 

from a master. Section 271(f) contains no instruction to gauge when

duplication is easy and cheap enough to deem a copy in fact made 

abroad nevertheless “supplie[d] . . . from the United States.” The absence of anything addressing copying in the statutory text weighs

against a judicial determination that replication abroad of a master

dispatched from the United States “supplies” the foreign-made copies

from this country. Pp. 12–14. 

(c) Any doubt that Microsoft’s conduct falls outside §271(f)’s compass would be resolved by the presumption against extraterritoriality. Foreign conduct is generally the domain of foreign law, and in

the patent area, that law may embody different policy judgments 

about the relative rights of inventors, competitors, and the public. 

Applied here, the presumption tugs strongly against construing 

§271(f) to encompass as a “component” not only a physical copy of 

software, but also software’s intangible code, and to render “supplie[d] . . . from the United States” not only exported copies of software, but also duplicates made abroad. Foreign law alone, not 

United States law, currently governs the manufacture and sale of 

components of patented inventions in foreign countries. If AT&T desires to prevent copying abroad, its remedy lies in obtaining and enforcing foreign patents. Pp. 14–16. 

(d) While reading §271(f) to exclude from coverage foreign-made 
4 MICROSOFT CORP. v. AT&T CORP. 

Syllabus 

copies of software may create a “loophole” in favor of software makers, the Court is not persuaded that dynamic judicial interpretation

of §271(f) is in order; the “loophole” is properly left for Congress to

consider, and to close if it finds such action warranted. Section 271(f) 

was a direct response to a gap in U. S. patent law revealed by Deepsouth Packing Co. v. Laitram Corp., 406 U. S. 518, where the items 

exported were kits containing all the physical, readily assemblable

parts of a machine (not an intangible set of instructions), and those 

parts themselves (not foreign-made copies of them) would be combined abroad by foreign buyers. Having attended to that gap, Congress did not address other arguable gaps, such as the loophole AT&T 

describes. Given the expanded extraterritorial thrust AT&T’s reading of §271(f) entails, the patent-protective determination AT&T

seeks must be left to Congress. Cf. Sony Corp. of America v. Universal City Studios, Inc., 464 U. S. 417, 431. Congress is doubtless

aware of the ease with which electronic media such as software can 

be copied, and has not left the matter untouched. See the Digital

Millennium Copyright Act, 17 U. S. C. §1201 et seq. If patent law is 

to be adjusted better to account for the realities of software distribution, the alteration should be made after focused legislative consideration, not by the Judiciary forecasting Congress’ likely disposition.

Pp. 17–19. 

414 F. 3d 1366, reversed. 

GINSBURG, J., delivered the opinion of the Court, except as to footnote 

14. SCALIA, KENNEDY, and SOUTER, JJ., joined that opinion in full. 

ALITO, J., filed an opinion concurring as to all but footnote 14, in which 

THOMAS and BREYER, JJ., joined. STEVENS, J., filed a dissenting opinion. ROBERTS, C. J., took no part in the consideration or decision of the 

case. 
_________________ 

_________________ 

Cite as: 550 U. S. ____ (2007) 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, Washington, 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. 05–1056 

MICROSOFT CORPORATION, PETITIONER v.

AT&T CORP. 

ON WRIT OF CERTIORARI TO THE UNITED STATES COURT OF 

APPEALS FOR THE FEDERAL CIRCUIT

[April 30, 2007] 

JUSTICE GINSBURG delivered the opinion of the Court, 

except as to footnote 14. 

It is the general rule under United States patent law 

that no infringement occurs when a patented product is 

made and sold in another country. There is an exception.

Section 271(f) of the Patent Act, adopted in 1984, provides

that infringement does occur when one “supplies . . . from 

the United States,” for “combination” abroad, a patented 

invention’s “components.” 35 U. S. C. §271(f)(1). This case 

concerns the applicability of §271(f) to computer software

first sent from the United States to a foreign manufacturer on a master disk, or by electronic transmission, then 

copied by the foreign recipient for installation on computers made and sold abroad. 

AT&T holds a patent on an apparatus for digitally 

encoding and compressing recorded speech. Microsoft’s 

Windows operating system, it is conceded, has the potential to infringe AT&T’s patent, because Windows incorporates software code that, when installed, enables a computer to process speech in the manner claimed by that 

patent. It bears emphasis, however, that uninstalled 
2 MICROSOFT CORP. v. AT&T CORP. 

Opinion of the Court 

Windows software does not infringe AT&T’s patent any 

more than a computer standing alone does; instead, the

patent is infringed only when a computer is loaded with

Windows and is thereby rendered capable of performing as

the patented speech processor. The question before us: 

Does Microsoft’s liability extend to computers made in

another country when loaded with Windows software

copied abroad from a master disk or electronic transmission dispatched by Microsoft from the United States? Our 

answer is “No.” 

The master disk or electronic transmission Microsoft 

sends from the United States is never installed on any of

the foreign-made computers in question. Instead, copies 

made abroad are used for installation. Because Microsoft 

does not export from the United States the copies actually 

installed, it does not “suppl[y] . . . from the United States” 

“components” of the relevant computers, and therefore is 

not liable under §271(f) as currently written. 

Plausible arguments can be made for and against extending §271(f) to the conduct charged in this case as 

infringing AT&T’s patent. Recognizing that §271(f) is an

exception to the general rule that our patent law does not

apply extraterritorially, we resist giving the language in 

which Congress cast §271(f) an expansive interpretation.

Our decision leaves to Congress’ informed judgment any

adjustment of §271(f) it deems necessary or proper. 

I 

Our decision some 35 years ago in Deepsouth Packing 

Co. v. Laitram Corp., 406 U. S. 518 (1972), a case about a 

shrimp deveining machine, led Congress to enact §271(f).

In that case, Laitram, holder of a patent on the time-andexpense-saving machine, sued Deepsouth, manufacturer of 

an infringing deveiner. Deepsouth conceded that the 

Patent Act barred it from making and selling its deveining 

machine in the United States, but sought to salvage a 
Cite as: 550 U. S. ____ (2007) 3 

Opinion of the Court 

portion of its business: Nothing in United States patent 

law, Deepsouth urged, stopped it from making in the 

United States the parts of its deveiner, as opposed to the

machine itself, and selling those parts to foreign buyers for

assembly and use abroad. Id., at 522–524.1 We agreed.

Interpreting our patent law as then written, we reiterated in Deepsouth that it was “not an infringement to 

make or use a patented product outside of the United 

States.” Id., at 527; see 35 U. S. C. §271(a) (1970 ed.) 

(“[W]hoever without authority makes, uses or sells any 

patented invention, within the United States during the 

term of the patent therefor, infringes the patent.”). Deepsouth’s foreign buyers did not infringe Laitram’s patent, 

we held, because they assembled and used the deveining 

machines outside the United States. Deepsouth, we therefore concluded, could not be charged with inducing or

contributing to an infringement. 406 U. S., at 526–527.2 

Nor could Deepsouth be held liable as a direct infringer, 

for it did not make, sell, or use the patented invention—

the fully assembled deveining machine—within the 

United States. The parts of the machine were not themselves patented, we noted, hence export of those parts, 

unassembled, did not rank as an infringement of 

Laitram’s patent. Id., at 527–529. 

Laitram had argued in Deepsouth that resistance to 

extension of the patent privilege to cover exported parts 

—————— 

1Deepsouth shipped its deveining equipment “to foreign customers in 

three separate boxes, each containing only parts of the 13⁄4-ton machines, yet the whole [was] assemblable in less than one hour.” Deepsouth Packing Co. v. Laitram Corp., 406 U. S. 518, 524 (1972). 2See 35 U. S. C. §271(b) (1970 ed.) (“Whoever actively induces infringement of a patent shall be liable as an infringer.”); §271(c) (rendering liable as a contributory infringer anyone who sells or imports a

“component” of a patented invention, “knowing the same to be especially made or especially adapted for use in an infringement of such 

patent, and not a staple article or commodity of commerce suitable for

substantial non-infringing use”). 
4 MICROSOFT CORP. v. AT&T CORP. 

Opinion of the Court 

“derived from too narrow and technical an interpretation

of the [Patent Act].” Id., at 529. Rejecting that argument, 

we referred to prior decisions holding that “a combination

patent protects only against the operable assembly of the

whole and not the manufacture of its parts.” Id., at 528. 

Congress’ codification of patent law, we said, signaled no

intention to broaden the scope of the privilege. Id., at 530 

(“When, as here, the Constitution is permissive, the sign of

how far Congress has chosen to go can come only from

Congress.”). And we again emphasized that 

“[o]ur patent system makes no claim to extraterritorial effect; these acts of Congress do not, and were not 

intended to, operate beyond the limits of the United 

States; and we correspondingly reject the claims of 

others to such control over our markets.” Id., at 531 

(quoting Brown v. Duchesne, 19 How. 183, 195 (1857)). 

Absent “a clear congressional indication of intent,” we 

stated, courts had no warrant to stop the manufacture and 

sale of the parts of patented inventions for assembly and 

use abroad. 406 U. S., at 532. 

Focusing its attention on Deepsouth, Congress enacted

§271(f). See Patent Law Amendments Act of 1984, §101, 

98 Stat. 3383; Fisch & Allen, The Application of Domestic

Patent Law to Exported Software: 35 U. S. C. §271(f), 25 

U. Pa. J. Int’l Econ. L. 557, 565 (2004) (“Congress specifically intended §271(f) as a response to the Supreme

Court’s decision in Deepsouth”).3 The provision expands 

—————— 

3See also, e.g., Patent Law Amendments of 1984, S. Rep. No. 98–663,

pp. 2–3 (1984) (describing §271(f) as “a response to the Supreme Court’s

1972 Deepsouth decision which interpreted the patent law not to make

it infringement where the final assembly and sale is abroad”); Sectionby-Section Analysis of H. R. 6286, 130 Cong. Rec. 28069 (1984) (“This

proposal responds to the United States Supreme Court decision in 

Deepsouth . . . concerning the need for a legislative solution to close a 

loophole in [the] patent law.”). 
Cite as: 550 U. S. ____ (2007) 5 

Opinion of the Court 

the definition of infringement to include supplying from 

the United States a patented invention’s components: 

“(1) Whoever without authority supplies or causes

to be supplied in or from the United States all or a 

substantial portion of the components of a patented 

invention, where such components are uncombined in

whole or in part, in such manner as to actively induce 

the combination of such components outside of the

United States in a manner that would infringe the

patent if such combination occurred within the United 

States, shall be liable as an infringer. 

“(2) Whoever without authority supplies or causes

to be supplied in or from the United States any component of a patented invention that is especially made

or especially adapted for use in the invention and not 

a staple article or commodity of commerce suitable for

substantial noninfringing use, where such component

is uncombined in whole or in part, knowing that such 

component is so made or adapted and intending that 

such component will be combined outside of the 

United States in a manner that would infringe the

patent if such combination occurred within the United 

States, shall be liable as an infringer.” 35 U. S. C. 

§271(f). 

II 

Windows is designed, authored, and tested at Microsoft’s Redmond, Washington, headquarters. Microsoft 

sells Windows to end users and computer manufacturers, 

both foreign and domestic. Purchasing manufacturers

install the software onto the computers they sell. Microsoft sends to each of the foreign manufacturers a master 

version of Windows, either on a disk or via encrypted

electronic transmission. The manufacturer uses the master version to generate copies. Those copies, not the master sent by Microsoft, are installed on the foreign manu-
6 MICROSOFT CORP. v. AT&T CORP. 

Opinion of the Court 

facturer’s computers. Once assembly is complete, the

foreign-made computers are sold to users abroad. App. to 

Pet. for Cert. 45a–46a.4 

AT&T’s patent (’580 patent) is for an apparatus (as

relevant here, a computer) capable of digitally encoding

and compressing recorded speech. Windows, the parties

agree, contains software that enables a computer to process speech in the manner claimed by the ’580 patent. In 

2001, AT&T filed an infringement suit in the United 

States District Court for the Southern District of New 

York, charging Microsoft with liability for domestic and 

foreign installations of Windows. 

Neither Windows software (e.g., in a box on the shelf) 

nor a computer standing alone (i.e., without Windows 

installed) infringes AT&T’s patent. Infringement occurs

only when Windows is installed on a computer, thereby 

rendering it capable of performing as the patented speech 

processor. Microsoft stipulated that by installing Windows on its own computers during the software development process, it directly infringed the ’580 patent.5 Microsoft further acknowledged that by licensing copies of

Windows to manufacturers of computers sold in the

United States, it induced infringement of AT&T’s patent.6 

Id., at 42a; Brief for Petitioner 3–4; Brief for Respondent

9, 19. 

Microsoft denied, however, any liability based on the

master disks and electronic transmissions it dispatched to 

—————— 

4Microsoft also distributes Windows to foreign manufacturers indirectly, by sending a master version to an authorized foreign “replicator”; the replicator then makes copies and ships them to the manufacturers. App. to Pet. for Cert. 45a–46a. 5See 35 U. S. C. §271(a) (“[W]hoever without authority makes, uses, 

offers to sell, or sells any patented invention, within the United States 

or imports into the United States any patented invention during the 

term of the patent therefor, infringes the patent.”). 6See §271(b) (“Whoever actively induces infringement of a patent

shall be liable as an infringer.”). 
Cite as: 550 U. S. ____ (2007) 7 

Opinion of the Court 

foreign manufacturers, thus joining issue with AT&T. By

sending Windows to foreign manufacturers, AT&T contended, Microsoft “supplie[d] . . . from the United States,”

for “combination” abroad, “components” of AT&T’s patented speech processor; accordingly, AT&T urged, Microsoft was liable under §271(f). See supra, at 5 (reproducing 

text of §271(f)). Microsoft responded that unincorporated

software, because it is intangible information, cannot be

typed a “component” of an invention under §271(f). In any

event, Microsoft urged, the foreign-generated copies of 

Windows actually installed abroad were not “supplie[d] . . . 

from the United States.” Rejecting these responses, the 

District Court held Microsoft liable under §271(f). 71 

USPQ 2d 1118 (SDNY 2004). On appeal, a divided panel 

of the Court of Appeals for the Federal Circuit affirmed.

414 F. 3d 1366 (2005). We granted certiorari, 549 U. S.

___ (2006), and now reverse. 

III 

A 

This case poses two questions: First, when, or in what

form, does software qualify as a “component” under

§271(f)? Second, were “components” of the foreign-made 

computers involved in this case “supplie[d]” by Microsoft

“from the United States”? 7 

As to the first question, no one in this litigation argues 

that software can never rank as a “component” under

§271(f). The parties disagree, however, over the stage at

which software becomes a component. Software, the “set 

of instructions, known as code, that directs a computer to 

—————— 

7The record leaves unclear which paragraph of §271(f) AT&T’s claim 

invokes. While there are differences between §271(f)(1) and (f)(2), see, 

e.g., infra, at 18, n. 18, the parties do not suggest that those differences 

are outcome determinative. Cf. infra, at 14–15, n. 16 (explaining why

both paragraphs yield the same result). For clarity’s sake, we focus our 

analysis on the text of §271(f)(1). 
8 MICROSOFT CORP. v. AT&T CORP. 

Opinion of the Court 

perform specified functions or operations,” Fantasy Sports 

Properties, Inc. v. Sportsline.com, Inc., 287 F. 3d 1108, 

1118 (CA Fed. 2002), can be conceptualized in (at least) 

two ways. One can speak of software in the abstract: the 

instructions themselves detached from any medium. (An 

analogy: The notes of Beethoven’s Ninth Symphony.) One 

can alternatively envision a tangible “copy” of software,

the instructions encoded on a medium such as a CD-ROM. 

(Sheet music for Beethoven’s Ninth.) AT&T argues that

software in the abstract, not simply a particular copy of

software, qualifies as a “component” under §271(f). Microsoft and the United States argue that only a copy of software, not software in the abstract, can be a component.8 

The significance of these diverse views becomes apparent when we turn to the second question: Were components of the foreign-made computers involved in this case 

“supplie[d]” by Microsoft “from the United States”? If the 

relevant components are the copies of Windows actually 

installed on the foreign computers, AT&T could not persuasively argue that those components, though generated 

abroad, were “supplie[d] . . . from the United States” as 

§271(f) requires for liability to attach.9 If, on the other 

—————— 

8Microsoft and the United States stress that to count as a component, 

the copy of software must be expressed as “object code.” “Software in 

the form in which it is written and understood by humans is called 

‘source code.’ To be functional, however, software must be converted (or 

‘compiled’) into its machine-usable version,” a sequence of binary 

number instructions typed “object code.” Brief for United States as 

Amicus Curiae 4, n. 1; 71 USPQ 2d 1118, 1119, n. 5 (SDNY 2004)

(recounting Microsoft’s description of the software development process). It is stipulated that object code was on the master disks and

electronic transmissions Microsoft dispatched from the United States. 9On this view of “component,” the copies of Windows on the master

disks and electronic transmissions that Microsoft sent from the United 

States could not themselves serve as a basis for liability, because those

copies were not installed on the foreign manufacturers’ computers. See 

§271(f)(1) (encompassing only those components “combin[ed] . . . outside

of the United States in a manner that would infringe the patent if such 
Cite as: 550 U. S. ____ (2007) 9 

Opinion of the Court 

hand, Windows in the abstract qualifies as a component 

within §271(f)’s compass, it would not matter that the 

master copies of Windows software dispatched from the

United States were not themselves installed abroad as 

working parts of the foreign computers.10 

With this explanation of the relationship between the 

two questions in view, we further consider the twin 

inquiries. 

B 

First, when, or in what form, does software become a 

“component” under §271(f)? We construe §271(f)’s terms 

“in accordance with [their] ordinary or natural meaning.” 

FDIC v. Meyer, 510 U. S. 471, 476 (1994). Section 271(f) 

applies to the supply abroad of the “components of a patented invention, where such components are uncombined 

in whole or in part, in such manner as to actively induce 

the combination of such components.” §271(f)(1) (emphasis

added). The provision thus applies only to “such components”11 as are combined to form the “patented invention”

at issue. The patented invention here is AT&T’s speechprocessing computer.

Until it is expressed as a computer-readable “copy,” e.g., 

on a CD-ROM, Windows software—indeed any software

detached from an activating medium—remains uncombinable. It cannot be inserted into a CD-ROM drive or 

downloaded from the Internet; it cannot be installed or 

executed on a computer. Abstract software code is an idea 

—————— 

combination occurred within the United States”). 10The Federal Circuit panel in this case, relying on that court’s prior 

decision in Eolas Technologies Inc. v. Microsoft Corp., 399 F. 3d 1325 

(2005), held that software qualifies as a component under §271(f). We 

are unable to determine, however, whether the Federal Circuit panels

regarded as a component software in the abstract, or a copy of software. 11 “Component” is commonly defined as “a constituent part,” “element,” or “ingredient.” Webster’s Third New International Dictionary

of the English Language 466 (1981). 
10 MICROSOFT CORP. v. AT&T CORP. 

Opinion of the Court 

without physical embodiment, and as such, it does not 

match §271(f)’s categorization: “components” amenable to 

“combination.” Windows abstracted from a tangible copy 

no doubt is information—a detailed set of instructions— 

and thus might be compared to a blueprint (or anything 

containing design information, e.g., a schematic, template, 

or prototype). A blueprint may contain precise instructions for the construction and combination of the components of a patented device, but it is not itself a combinable

component of that device. AT&T and its amici do not 

suggest otherwise. Cf. Pellegrini v. Analog Devices, Inc., 

375 F. 3d 1113, 1117–1119 (CA Fed. 2004) (transmission 

abroad of instructions for production of patented computer

chips not covered by §271(f)).

AT&T urges that software, at least when expressed as

machine-readable object code, is distinguishable from

design information presented in a blueprint. Software, 

unlike a blueprint, is “modular”; it is a stand-alone product developed and marketed “for use on many different 

types of computer hardware and in conjunction with many

other types of software.” Brief for Respondent 5; Tr. of 

Oral Arg. 46. Software’s modularity persists even after

installation; it can be updated or removed (deleted) without affecting the hardware on which it is installed. Ibid. 

Software, unlike a blueprint, is also “dynamic.” Tr. of Oral 

Arg. 46. After a device has been built according to a blueprint’s instructions, the blueprint’s work is done (as AT&T

puts it, the blueprint’s instructions have been “exhausted,” 

ibid.). Software’s instructions, in contrast, are contained 

in and continuously performed by a computer. Brief for 

Respondent 27–28; Tr. of Oral Arg. 46. See also Eolas 

Technologies Inc. v. Microsoft Corp., 399 F. 3d 1325, 1339 

(CA Fed. 2005) (“[S]oftware code . . . drives the functional 

nucleus of the finished computer product.” (quoting Imagexpo, L. L. C. v. Microsoft Corp., 299 F. Supp. 2d 550, 

553 (ED Va. 2003))). 
Cite as: 550 U. S. ____ (2007) 11 

Opinion of the Court 

The distinctions advanced by AT&T do not persuade

us to characterize software, uncoupled from a medium, 

as a combinable component. Blueprints too, or any 

design information for that matter, can be independently

developed, bought, and sold. If the point of AT&T’s 

argument is that we do not see blueprints lining stores’ 

shelves, the same observation may be made about software in the abstract: What retailers sell, and consumers 

buy, are copies of software. Likewise, before software 

can be contained in and continuously performed by a 

computer, before it can be updated or deleted, an actual,

physical copy of the software must be delivered by CDROM or some other means capable of interfacing with 

the computer.12 

Because it is so easy to encode software’s instructions

onto a medium that can be read by a computer, AT&T 

intimates, that extra step should not play a decisive role 

under §271(f). But the extra step is what renders the 

software a usable, combinable part of a computer; easy or

not, the copy-producing step is essential. Moreover, many 

tools may be used easily and inexpensively to generate the

parts of a device. A machine for making sprockets might

be used by a manufacturer to produce tens of thousands of

sprockets an hour. That does not make the machine a 

“component” of the tens of thousands of devices in which

the sprockets are incorporated, at least not under any 

ordinary understanding of the term “component.” Con-

—————— 

12The dissent, embracing AT&T’s argument, contends that, “unlike a 

blueprint that merely instructs a user how to do something, software 

actually causes infringing conduct to occur.” Post, at 3 (STEVENS, J., 

dissenting). We have emphasized, however, that Windows can “caus[e] 

infringing conduct to occur”—i.e., function as part of AT&T’s speechprocessing computer—only when expressed as a computer-readable 

copy. Abstracted from a usable copy, Windows code is intangible,

uncombinable information, more like notes of music in the head of a 

composer than “a roller that causes a player piano to produce sound.” 

Ibid. 
12 MICROSOFT CORP. v. AT&T CORP. 

Opinion of the Court 

gress, of course, might have included within §271(f)’s 

compass, for example, not only combinable “components” 

of a patented invention, but also “information, instructions, or tools from which those components readily may 

be generated.” It did not. In sum, a copy of Windows, not 

Windows in the abstract, qualifies as a “component” under

§271(f).13 

C 

The next question, has Microsoft “supplie[d] . . . from 

the United States” components of the computers here 

involved? Under a conventional reading of §271(f)’s text,

the answer would be “No,” for the foreign-made copies of 

Windows actually installed on the computers were “supplie[d]” from places outside the United States. The Federal Circuit majority concluded, however, that “for software ‘components,’ the act of copying is subsumed in the 

act of ‘supplying.’” 414 F. 3d, at 1370. A master sent 

abroad, the majority observed, differs not at all from the

exact copies, easily, inexpensively, and swiftly generated 

from the master; hence “sending a single copy abroad with 

the intent that it be replicated invokes §271(f) liability for 

th[e] foreign-made copies.” Ibid.; cf. post, at 2 (STEVENS, 

J., dissenting) (“[A] master disk is the functional equivalent of a warehouse of components . . . that Microsoft fully 

expects to be incorporated into foreign-manufactured 

computers.”). 

Judge Rader, dissenting, noted that “supplying” is ordinarily understood to mean an activity separate and dis-

—————— 

13We need not address whether software in the abstract, or any other

intangible, can ever be a component under §271(f). If an intangible

method or process, for instance, qualifies as a “patented invention”

under §271(f) (a question as to which we express no opinion), the

combinable components of that invention might be intangible as well. 

The invention before us, however, AT&T’s speech-processing computer, 

is a tangible thing. 
Cite as: 550 U. S. ____ (2007) 13 

Opinion of the Court 

tinct from any subsequent “copying, replicating, or reproducing—in effect manufacturing.” 414 F. 3d, at 1372– 

1373 (internal quotation marks omitted); see id., at 1373 

(“[C]opying and supplying are separate acts with different 

consequences—particularly when the ‘supplying’ occurs in

the United States and the copying occurs in Dϋsseldorf or 

Tokyo. As a matter of logic, one cannot supply one hundred components of a patented invention without first 

making one hundred copies of the component . . . .”). He 

further observed: “The only true difference between making and supplying software components and physical 

components [of other patented inventions] is that copies of

software components are easier to make and transport.” 

Id., at 1374. But nothing in §271(f)’s text, Judge Rader 

maintained, renders ease of copying a relevant, no less

decisive, factor in triggering liability for infringement. See 

ibid. We agree.

Section 271(f) prohibits the supply of components “from

the United States . . . in such manner as to actively induce 

the combination of such components.” §271(f)(1) (emphasis

added). Under this formulation, the very components

supplied from the United States, and not copies thereof, 

trigger §271(f) liability when combined abroad to form the 

patented invention at issue. Here, as we have repeatedly 

noted, see supra, at 1–2, 5–6, the copies of Windows actually installed on the foreign computers were not themselves supplied from the United States.14 Indeed, those 

copies did not exist until they were generated by third

parties outside the United States.15 Copying software 

—————— 

14 In a footnote, Microsoft suggests that even a disk shipped from the 

United States, and used to install Windows directly on a foreign computer, would not give rise to liability under §271(f) if the disk were 

removed after installation. See Brief for Petitioner 37, n. 11; cf. post, at 

2–4 (ALITO, J., concurring). We need not and do not reach that issue 

here. 15The dissent analogizes Microsoft’s supply of master versions of 
14 MICROSOFT CORP. v. AT&T CORP. 

Opinion of the Court 

abroad, all might agree, is indeed easy and inexpensive. 

But the same could be said of other items: “Keys or machine parts might be copied from a master; chemical or 

biological substances might be created by reproduction; 

and paper products might be made by electronic copying

and printing.” Brief for United States as Amicus Curiae 

24. See also supra, at 11–12 (rejecting argument similarly 

based on ease of copying in construing “component”).

Section 271(f) contains no instruction to gauge when duplication is easy and cheap enough to deem a copy in fact

made abroad nevertheless “supplie[d] . . . from the United

States.” The absence of anything addressing copying in

the statutory text weighs against a judicial determination 

that replication abroad of a master dispatched from the 

United States “supplies” the foreign-made copies from the 

United States within the intendment of §271(f).16 

—————— 

Windows abroad to “the export of an inventory of . . . knives to be 

warehoused until used to complete the assembly of an infringing 

machine.” Post, at 2. But as we have underscored, foreign-made copies

of Windows, not the masters Microsoft dispatched from the United 

States, were installed on the computers here involved. A more apt

analogy, therefore, would be the export of knives for copying abroad, 

with the foreign-made copies “warehoused until used to complete the 

assembly of an infringing machine.” Ibid. Without stretching §271(f) 

beyond the text Congress composed, a copy made entirely abroad does 

not fit the description “supplie[d] . . . from the United States.” 16Our analysis, while focusing on §271(f)(1), is equally applicable to 

§271(f)(2). But cf. post, at 1 (STEVENS, J., dissenting) (asserting “paragraph (2) . . . best supports AT&T’s position here”). While the two 

paragraphs differ, among other things, on the quantity of components 

that must be “supplie[d] . . . from the United States” for liability to 

attach, see infra, at 18, n. 18, that distinction does not affect our 

analysis. Paragraph (2), like (1), covers only a “component” amenable

to “combination.” §271(f)(2); see supra, at 9–12 (explaining why Windows in the abstract is not a combinable component). Paragraph (2), 

like (1), encompasses only the “[s]uppl[y] . . . from the United States” of

“such [a] component” as will itself “be combined outside of the United 

States.” §271(f)(2); see supra, at 12–13 and this page (observing that 

foreign-made copies of Windows installed on computers abroad were 
Cite as: 550 U. S. ____ (2007) 15 

Opinion of the Court 

D 

Any doubt that Microsoft’s conduct falls outside §271(f)’s

compass would be resolved by the presumption against 

extraterritoriality, on which we have already touched. See 

supra, at 2, 4. The presumption that United States law

governs domestically but does not rule the world applies

with particular force in patent law. The traditional understanding that our patent law “operate[s] only domestically and d[oes] not extend to foreign activities,” Fisch & 

Allen, supra, at 559, is embedded in the Patent Act itself, 

which provides that a patent confers exclusive rights in an

invention within the United States. 35 U. S. C. §154(a)(1) 

(patentee’s rights over invention apply to manufacture, 

use, or sale “throughout the United States” and to importation “into the United States”). See Deepsouth, 406 U. S., 

at 531 (“Our patent system makes no claim to extraterritorial effect”; our legislation “d[oes] not, and [was] not

intended to, operate beyond the limits of the United 

States, and we correspondingly reject the claims of others 

to such control over our markets.” (quoting Brown, 19 

How., at 195)). 

As a principle of general application, moreover, we have 

stated that courts should “assume that legislators take

account of the legitimate sovereign interests of other

nations when they write American laws.” F. Hoffmann-La 

Roche Ltd v. Empagran S. A., 542 U. S. 155, 164 (2004); 

see EEOC v. Arabian American Oil Co., 499 U. S. 244, 248 

(1991). Thus, the United States accurately conveyed in

this case: “Foreign conduct is [generally] the domain of 

foreign law,” and in the area here involved, in particular,

foreign law “may embody different policy judgments about

the relative rights of inventors, competitors, and the pub-

—————— 

not “supplie[d] . . . from the United States”). It is thus unsurprising

that AT&T does not join the dissent in suggesting that the outcome 

might turn on whether we view the case under paragraph (1) or (2). 
16 MICROSOFT CORP. v. AT&T CORP. 

Opinion of the Court 

lic in patented inventions.” Brief for United States as 

Amicus Curiae 28. Applied to this case, the presumption

tugs strongly against construction of §271(f) to encompass

as a “component” not only a physical copy of software, but

also software’s intangible code, and to render “supplie[d]

. . . from the United States” not only exported copies of

software, but also duplicates made abroad.

AT&T argues that the presumption is inapplicable 

because Congress enacted §271(f) specifically to extend the 

reach of United States patent law to cover certain activity

abroad. But as this Court has explained, “the presumption is not defeated . . . just because [a statute] specifically

addresses [an] issue of extraterritorial application,” Smith 

v. United States, 507 U. S. 197, 204 (1993); it remains 

instructive in determining the extent of the statutory

exception. See Empagran, 542 U. S., at 161–162, 164–165; 

Smith, 507 U. S., at 204. 

AT&T alternately contends that the presumption holds

no sway here given that §271(f), by its terms, applies only 

to domestic conduct, i.e., to the supply of a patented invention’s components “from the United States.” §271(f)(1).

AT&T’s reading, however, “converts a single act of supply

from the United States into a springboard for liability 

each time a copy of the software is subsequently made

[abroad] and combined with computer hardware [abroad] 

for sale [abroad.]” Brief for United States as Amicus 

Curiae 29; see 414 F. 3d, at 1373, 1375 (Rader, J., dissenting). In short, foreign law alone, not United States law, 

currently governs the manufacture and sale of components

of patented inventions in foreign countries. If AT&T 

desires to prevent copying in foreign countries, its remedy

today lies in obtaining and enforcing foreign patents. See 

Deepsouth, 406 U. S., at 531.17 

—————— 

17AT&T has secured patents for its speech processor in Canada,

France, Germany, Great Britain, Japan, and Sweden. App. in No. 04– 
Cite as: 550 U. S. ____ (2007) 17 

Opinion of the Court

IV 

AT&T urges that reading §271(f) to cover only those 

copies of software actually dispatched from the United 

States creates a “loophole” for software makers. Liability

for infringing a United States patent could be avoided, as

Microsoft’s practice shows, by an easily arranged circumvention: Instead of making installation copies of software 

in the United States, the copies can be made abroad, 

swiftly and at small cost, by generating them from a master supplied from the United States. The Federal Circuit 

majority found AT&T’s plea compelling: 

“Were we to hold that Microsoft’s supply by exportation of the master versions of the Windows® software—specifically for the purpose of foreign replication—avoids infringement, we would be subverting 

the remedial nature of §271(f), permitting a technical 

avoidance of the statute by ignoring the advances in 

a field of technology—and its associated industry

practices—that developed after the enactment of 

§271(f). . . . Section §271(f), if it is to remain effective, 

must therefore be interpreted in a manner that is appropriate to the nature of the technology at issue.”

414 F. 3d, at 1371. 

While the majority’s concern is understandable, we are not

persuaded that dynamic judicial interpretation of §271(f) 

is in order. The “loophole,” in our judgment, is properly 

left for Congress to consider, and to close if it finds such

action warranted. 

There is no dispute, we note again, that §271(f) is inapplicable to the export of design tools—blueprints, schemat-

—————— 

1285 (CA Fed.), p. 1477. AT&T and its amici do not relate what protections and remedies are, or are not, available under these foreign regimes. Cf. Brief for Respondent 46 (observing that “foreign patent

protections are sometimes weaker than their U. S. counterparts” 

(emphasis added)). 
18 MICROSOFT CORP. v. AT&T CORP. 

Opinion of the Court 

ics, templates, and prototypes—all of which may provide

the information required to construct and combine overseas the components of inventions patented under United 

States law. See supra, at 10–12. We have no license to 

attribute to Congress an unstated intention to place the 

information Microsoft dispatched from the United States

in a separate category.

Section 271(f) was a direct response to a gap in our 

patent law revealed by this Court’s Deepsouth decision. 

See supra, at 4, and n. 3. The facts of that case were 

undeniably at the fore when §271(f) was in the congressional hopper. In Deepsouth, the items exported were kits

containing all the physical, readily assemblable parts of a 

shrimp deveining machine (not an intangible set of instructions), and those parts themselves (not foreign-made

copies of them) would be combined abroad by foreign 

buyers. Having attended to the gap made evident in 

Deepsouth, Congress did not address other arguable gaps: 

Section 271(f) does not identify as an infringing act conduct in the United States that facilitates making a component of a patented invention outside the United States; 

nor does the provision check “suppl[ying] . . . from the 

United States” information, instructions, or other materials needed to make copies abroad.18 Given that Congress

did not home in on the loophole AT&T describes, and in

view of the expanded extraterritorial thrust AT&T’s reading of §271(f) entails, our precedent leads us to leave in 

Congress’ court the patent-protective determination AT&T 

—————— 

18Section 271(f)’s text does, in one respect, reach past the facts of 

Deepsouth. While Deepsouth exported kits containing all the parts of

its deveining machines, §271(f)(1) applies to the supply abroad of “all or 

a substantial portion of” a patented invention’s components. And 

§271(f)(2) applies to the export of even a single component if it is

“especially made or especially adapted for use in the invention and not

a staple article or commodity of commerce suitable for substantial 

noninfringing use.” 
Cite as: 550 U. S. ____ (2007) 19 

Opinion of the Court 

seeks. Cf. Sony Corp. of America v. Universal City Studios, Inc., 464 U. S. 417, 431 (1984) (“In a case like this, in

which Congress has not plainly marked our course, we

must be circumspect in construing the scope of rights 

created by a legislative enactment which never contemplated such a calculus of interests.”).

Congress is doubtless aware of the ease with which

software (and other electronic media) can be copied, and

has not left the matter untouched. In 1998, Congress

addressed “the ease with which pirates could copy and 

distribute a copyrightable work in digital form.” Universal 

City Studios, Inc. v. Corley, 273 F. 3d 429, 435 (CA2 2001). 

The resulting measure, the Digital Millennium Copyright 

Act, 17 U. S. C. §1201 et seq., “backed with legal sanctions

the efforts of copyright owners to protect their works from

piracy behind digital walls such as encryption codes or

password protections.” Universal City Studios, 273 F. 3d, 

at 435. If the patent law is to be adjusted better “to account for the realities of software distribution,” 414 F. 3d, 

at 1370, the alteration should be made after focused legislative consideration, and not by the Judiciary forecasting 

Congress’ likely disposition. 

* * * 

For the reasons stated, the judgment of the Court of

Appeals for the Federal Circuit is 

Reversed. 

THE CHIEF JUSTICE took no part in the consideration or 

decision of this case. 
_________________ 

_________________ 

Cite as: 550 U. S. ____ (2007) 1 

ALITO, J., concurring in part 

SUPREME COURT OF THE UNITED STATES 

No. 05–1056 

MICROSOFT CORPORATION, PETITIONER v.

AT&T CORP. 

ON WRIT OF CERTIORARI TO THE UNITED STATES COURT OF 

APPEALS FOR THE FEDERAL CIRCUIT

[April 30, 2007] 

JUSTICE ALITO, with whom JUSTICE THOMAS and 

JUSTICE BREYER join, concurring as to all but footnote 14. 

I agree with the Court that no “component[s]” of the

foreign-made computers involved in this case were “supplie[d]” by Microsoft “from the United States.” 35 U. S. C. 

§271(f)(1). I write separately because I reach this conclusion through somewhat different reasoning. 

I 

Computer programmers typically write programs in a 

“human readable” programming language. This “‘source 

code’” is then generally converted by the computer into a 

“machine readable code” or “machine language” expressed 

in a binary format. Brief for Respondent 5, n. 1 (citing R. 

White, How Computers Work 87, 94 (8th ed. 2006)); E.

Walters, Essential Guide to Computing 204–205 (2001). 

During the Windows writing process, the program exists

in the form of machine readable code on the magnetic tape 

fields of Microsoft’s computers’ hard drives. White, supra,

at 144–145; Walters, supra, at 54–55. 

When Microsoft finishes writing its Windows program

in the United States, it encodes Windows onto CD-ROMs 

known as “‘golden masters’” in the form of machine readable code. App. 31, ¶4. This is done by engraving each

disk in a specific way such that another computer can read 
2 MICROSOFT CORP. v. AT&T CORP. 

ALITO, J., concurring in part 

the engravings, understand what they mean, and write

the code onto the magnetic fields of its hard drive. Ibid.; 

Brief for Petitioner 4, n. 2. 

Microsoft ships these disks (or sends the code via electronic transmission) abroad, where the code is copied onto

other disks that are then placed into foreign-made computers for purposes of installing the Windows program. 

App. 31–32, ¶¶5–8. No physical aspect of a Windows CDROM—original disk or copy—is ever incorporated into the 

computer itself. See Stenograph L. L. C. v. Bossard Assocs., Inc., 144 F. 3d 96, 100 (CADC 1998) (noting that, 

within the context of the Copyright Act, “installation of 

software onto a computer results in ‘copying’”); White, 

supra, at 144–145, 172–173. The intact CD-ROM is then 

removed and may be discarded without affecting the 

computer’s implementation of the code.* The parties

agree for purposes of this litigation that a foreign-made

computer containing the Windows code would violate

AT&T’s patent if present in the United States. Pet. for 

Cert. 42a, ¶5. 

II 

A 

I agree with the Court that a component of a machine,

whether a shrimp deveiner or a personal computer, must 

be something physical. Ante, at 9–11. This is because the 

word “component,” when concerning a physical device, is 

most naturally read to mean a physical part of the device. 

See Webster’s Third New International Dictionary 466 

(1976) (component is a “constituent part: INGREDIENT”); 

Random House Dictionary of the English Language 301 

—————— 

* In a sense, the whole process is akin to an author living prior to the 

existence of the printing press, who created a story in his mind, wrote a 

manuscript, and sent it to a scrivener, who in turn copied the story by 

hand into a blank book. 
Cite as: 550 U. S. ____ (2007) 3 

ALITO, J., concurring in part 

(1967) (component is “a component part; constituent”). 

Furthermore, §271(f) requires that the component be

“combined” with other components to form the infringing

device, meaning that the component must remain a part of 

the device. Webster’s, supra, at 452 (combine means “to 

join in physical or chemical union”; “to become one”; “to 

unite into a chemical compound”); Random House, supra,

at 293 (combine means “to bring or join into a close union 

or whole”). For these reasons, I agree with the Court that

a set of instructions on how to build an infringing device, 

or even a template of the device, does not qualify as a 

component. Ante, at 9–10. 

B 

As the parties agree, an inventor can patent a machine 

that carries out a certain process, and a computer may

constitute such a machine when it executes commands— 

given to it by code—that allow it to carry out that process. 

Such a computer would not become an infringing device 

until enough of the code is installed on the computer to 

allow it to execute the process in question. The computer 

would not be an infringing device prior to the installation, 

or even during the installation. And the computer remains an infringing device after the installation process

because, even though the original installation device (such 

as a CD-ROM) has been removed from the computer, the 

code remains on the hard drive. 

III 

Here, Windows software originating in the United 

States was sent abroad, whether on a master disk or by

means of an electronic transmission, and eventually copied onto the hard drives of the foreign-made computers.

Once the copying process was completed, the Windows 

program was recorded in a physical form, i.e., in magnetic

fields on the computers’ hard drives. See Brief for Respondent 5. The physical form of the Windows program on 
4 MICROSOFT CORP. v. AT&T CORP. 

ALITO, J., concurring in part 

the master disk, i.e., the engravings on the CD-ROM,

remained on the disk in a form unchanged by the copying 

process. See Brief for Petitioner 4, n. 2 (citing White, How 

Computers Work, at 144–145, 172–173). There is nothing 

in the record to suggest that any physical part of the disk

became a physical part of the foreign-made computer, and 

such an occurrence would be contrary to the general workings of computers.

Because no physical object originating in the United 

States was combined with these computers, there was no

violation of §271(f). Accordingly, it is irrelevant that the

Windows software was not copied onto the foreign-made 

computers directly from the master disk or from an electronic transmission that originated in the United States.

To be sure, if these computers could not run Windows

without inserting and keeping a CD-ROM in the appropriate drive, then the CD-ROMs might be components of the 

computer. But that is not the case here. 

* * * 

Because the physical incarnation of code on the Windows CD-ROM supplied from the United States is not a

“component” of an infringing device under §271(f), it logically follows that a copy of such a CD-ROM also is not a 

component. For this reason, I join the Court’s opinion,

except for footnote 14. 
_________________ 

_________________ 

Cite as: 550 U. S. ____ (2007) 1 

STEVENS, J., dissenting 

SUPREME COURT OF THE UNITED STATES 

No. 05–1056 

MICROSOFT CORPORATION, PETITIONER v.

AT&T CORP. 

ON WRIT OF CERTIORARI TO THE UNITED STATES COURT OF 

APPEALS FOR THE FEDERAL CIRCUIT

[April 30, 2007] 

JUSTICE STEVENS, dissenting. 

As the Court acknowledges, “[p]lausible arguments can

be made for and against extending §271(f) to the conduct 

charged in this case as infringing AT&T’s patent.” Ante, 

at 2. Strong policy considerations, buttressed by the 

presumption against the application of domestic patent

law in foreign markets, support Microsoft Corporation’s 

position. I am, however, persuaded that an affirmance

of the Court of Appeals’ judgment is more faithful to

the intent of the Congress that enacted §271(f) than a 

reversal. 

The provision was a response to our decision in Deepsouth Packing Co. v. Laitram Corp., 406 U. S. 518 (1972), 

holding that a patent on a shrimp deveining machine had 

not been infringed by the export of components for assembly abroad. Paragraph (1) of §271(f) would have been 

sufficient on its own to overrule Deepsouth,* but it is 

paragraph (2) that best supports AT&T’s position here. It 

—————— 

* “Whoever without authority supplies or causes to be supplied in or

from the United States all or a substantial portion of the components of

a patented invention, where such components are uncombined in whole 

or in part, in such manner as to actively induce the combination of such

components outside of the United States in a manner that would 

infringe the patent if such combination occurred within the United 

States, shall be liable as an infringer.” 35 U. S. C. §271(f)(1). 
2 MICROSOFT CORP. v. AT&T CORP. 

STEVENS, J., dissenting 

provides: 

“Whoever without authority supplies or causes to be 

supplied in or from the United States any component

of a patented invention that is especially made or especially adapted for use in the invention and not a

staple article or commodity of commerce suitable for

substantial noninfringing use, where such component

is uncombined in whole or in part, knowing that such 

component is so made or adapted and intending that 

such component will be combined outside of the 

United States in a manner that would infringe the

patent if such combination occurred within the United 

States, shall be liable as an infringer.” §271(f)(2). 

Under this provision, the export of a specially designed 

knife that has no use other than as a part of a patented 

deveining machine would constitute infringement. It 

follows that §271(f)(2) would cover the export of an inventory of such knives to be warehoused until used to complete the assembly of an infringing machine. 

The relevant component in this case is not a physical

item like a knife. Both Microsoft and the Court think that 

means it cannot be a “component.” See ante, at 10. But if 

a disk with software inscribed on it is a “component,” I 

find it difficult to understand why the most important

ingredient of that component is not also a component. 

Indeed, the master disk is the functional equivalent of a 

warehouse of components—components that Microsoft

fully expects to be incorporated into foreign-manufactured 

computers. Put somewhat differently: On the Court’s 

view, Microsoft could be liable under §271(f) only if it 

sends individual copies of its software directly from the 

United States with the intent that each copy would be 

incorporated into a separate infringing computer. But it 

seems to me that an indirect transmission via a master 

disk warehouse is likewise covered by §271(f). 
Cite as: 550 U. S. ____ (2007) 3 

STEVENS, J., dissenting 

I disagree with the Court’s suggestion that because 

software is analogous to an abstract set of instructions, it

cannot be regarded as a “component” within the meaning 

of §271(f). See ante, at 9–10. Whether attached or detached from any medium, software plainly satisfies the 

dictionary definition of that word. See ante, at 9, n. 11 

(observing that “‘[c]omponent’ is commonly defined as ‘a

constituent part,’ ‘element,’ or ‘ingredient’”). And unlike a 

blueprint that merely instructs a user how to do something, software actually causes infringing conduct to occur.

It is more like a roller that causes a player piano to produce sound than sheet music that tells a pianist what to

do. Moreover, it is surely not “a staple article or commodity of commerce suitable for substantial noninfringing use” 

as that term is used in §271(f)(2). On the contrary, its sole 

intended use is an infringing use. 

I would therefore affirm the judgment of the Court of 

Appeals.