KSR International Co. v. Teleflex Inc.

(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

KSR INTERNATIONAL CO. v. TELEFLEX INC. ET AL.

CERTIORARI TO THE UNITED STATES COURT OF APPEALS FOR

THE FEDERAL CIRCUIT

No. 04–1350. Argued November 28, 2006—Decided April 30, 2007

To control a conventional automobile’s speed, the driver depresses or

releases the gas pedal, which interacts with the throttle via a cable or

other mechanical link. Because the pedal’s position in the footwell

normally cannot be adjusted, a driver wishing to be closer or farther

from it must either reposition himself in the seat or move the seat,

both of which can be imperfect solutions for smaller drivers in cars

with deep footwells. This prompted inventors to design and patent

pedals that could be adjusted to change their locations. The Asano

patent reveals a support structure whereby, when the pedal location

is adjusted, one of the pedal’s pivot points stays fixed. Asano is also

designed so that the force necessary to depress the pedal is the same

regardless of location adjustments. The Redding patent reveals a dif

ferent, sliding mechanism where both the pedal and the pivot point

are adjusted.

In newer cars, computer-controlled throttles do not operate through

force transferred from the pedal by a mechanical link, but open and

close valves in response to electronic signals. For the computer to

know what is happening with the pedal, an electronic sensor must

translate the mechanical operation into digital data. Inventors had

obtained a number of patents for such sensors. The so-called ’936

patent taught that it was preferable to detect the pedal’s position in

the pedal mechanism, not in the engine, so the patent disclosed a

pedal with an electronic sensor on a pivot point in the pedal assem

bly. The Smith patent taught that to prevent the wires connecting

the sensor to the computer from chafing and wearing out, the sensor

should be put on a fixed part of the pedal assembly rather than in or

on the pedal’s footpad. Inventors had also patented self-contained

modular sensors, which can be taken off the shelf and attached to any

2 KSR INT’L CO. v. TELEFLEX INC.

Syllabus

mechanical pedal to allow it to function with a computer-controlled

throttle. The ’068 patent disclosed one such sensor. Chevrolet also

manufactured trucks using modular sensors attached to the pedal

support bracket, adjacent to the pedal and engaged with the pivot

shaft about which the pedal rotates. Other patents disclose elec

tronic sensors attached to adjustable pedal assemblies. For example,

the Rixon patent locates the sensor in the pedal footpad, but is known

for wire chafing.

After petitioner KSR developed an adjustable pedal system for cars

with cable-actuated throttles and obtained its ’976 patent for the de

sign, General Motors Corporation (GMC) chose KSR to supply ad

justable pedal systems for trucks using computer-controlled throttles.

To make the ’976 pedal compatible with the trucks, KSR added a

modular sensor to its design. Respondents (Teleflex) hold the exclu

sive license for the Engelgau patent, claim 4 of which discloses a posi

tion-adjustable pedal assembly with an electronic pedal position sen

sor attached a fixed pivot point. Despite having denied a similar,

broader claim, the U. S. Patent and Trademark Office (PTO) had al

lowed claim 4 because it included the limitation of a fixed pivot posi

tion, which distinguished the design from Redding’s. Asano was nei

ther included among the Engelgau patent’s prior art references nor

mentioned in the patent’s prosecution, and the PTO did not have be

fore it an adjustable pedal with a fixed pivot point. After learning of

KSR’s design for GMC, Teleflex sued for infringement, asserting that

KSR’s pedal system infringed the Engelgau patent’s claim 4. KSR

countered that claim 4 was invalid under §103 of the Patent Act,

which forbids issuance of a patent when “the differences between the

subject matter sought to be patented and the prior art are such that

the subject matter as a whole would have been obvious at the time

the invention was made to a person having ordinary skill in the art.”

Graham v. John Deere Co. of Kansas City, 383 U. S. 1, 17–18, set

out an objective analysis for applying §103: “[T]he scope and content

of the prior art are . . . determined; differences between the prior art

and the claims at issue are . . . ascertained; and the level of ordinary

skill in the pertinent art resolved. Against this background the obvi

ousness or nonobviousness of the subject matter is determined. Such

secondary considerations as commercial success, long felt but un

solved needs, failure of others, etc., might be utilized to give light to

the circumstances surrounding the origin of the subject matter

sought to be patented.” While the sequence of these questions might

be reordered in any particular case, the factors define the controlling

inquiry. However, seeking to resolve the obviousness question with

more uniformity and consistency, the Federal Circuit has employed a

“teaching, suggestion, or motivation” (TSM) test, under which a pat

Cite as: 550 U. S. ____ (2007) 3

Syllabus

ent claim is only proved obvious if the prior art, the problem’s nature,

or the knowledge of a person having ordinary skill in the art reveals

some motivation or suggestion to combine the prior art teachings.

The District Court granted KSR summary judgment. After review

ing pedal design history, the Engelgau patent’s scope, and the rele

vant prior art, the court considered claim 4’s validity, applying Gra

ham’s framework to determine whether under summary-judgment

standards KSR had demonstrated that claim 4 was obvious. The

court found “little difference” between the prior art’s teachings and

claim 4: Asano taught everything contained in the claim except using

a sensor to detect the pedal’s position and transmit it to a computer

controlling the throttle. That additional aspect was revealed in, e.g.,

the ’068 patent and Chevrolet’s sensors. The court then held that

KSR satisfied the TSM test, reasoning (1) the state of the industry

would lead inevitably to combinations of electronic sensors and ad

justable pedals, (2) Rixon provided the basis for these developments,

and (3) Smith taught a solution to Rixon’s chafing problems by posi

tioning the sensor on the pedal’s fixed structure, which could lead to

the combination of a pedal like Asano with a pedal position sensor.

Reversing, the Federal Circuit ruled the District Court had not

applied the TSM test strictly enough, having failed to make findings

as to the specific understanding or principle within a skilled artisan’s

knowledge that would have motivated one with no knowledge of the

invention to attach an electronic control to the Asano assembly’s sup

port bracket. The Court of Appeals held that the District Court’s re

course to the nature of the problem to be solved was insufficient be

cause, unless the prior art references addressed the precise problem

that the patentee was trying to solve, the problem would not motivate

an inventor to look at those references. The appeals court found that

the Asano pedal was designed to ensure that the force required to de

press the pedal is the same no matter how the pedal is adjusted,

whereas Engelgau sought to provide a simpler, smaller, cheaper ad

justable electronic pedal. The Rixon pedal, said the court, suffered

from chafing but was not designed to solve that problem and taught

nothing helpful to Engelgau’s purpose. Smith, in turn, did not relate

to adjustable pedals and did not necessarily go to the issue of motiva

tion to attach the electronic control on the pedal assembly’s support

bracket. So interpreted, the court held, the patents would not have

led a person of ordinary skill to put a sensor on an Asano-like pedal.

That it might have been obvious to try that combination was likewise

irrelevant. Finally, the court held that genuine issues of material

fact precluded summary judgment.

Held: The Federal Circuit addressed the obviousness question in a nar

row, rigid manner that is inconsistent with §103 and this Court’s

4 KSR INT’L CO. v. TELEFLEX INC.

Syllabus

precedents. KSR provided convincing evidence that mounting an

available sensor on a fixed pivot point of the Asano pedal was a de

sign step well within the grasp of a person of ordinary skill in the

relevant art and that the benefit of doing so would be obvious. Its ar

guments, and the record, demonstrate that the Engelgau patent’s

claim 4 is obvious. Pp. 11–24.

1. Graham provided an expansive and flexible approach to the ob

viousness question that is inconsistent with the way the Federal Cir

cuit applied its TSM test here. Neither §103’s enactment nor Gra

ham’s analysis disturbed the Court’s earlier instructions concerning

the need for caution in granting a patent based on the combination of

elements found in the prior art. See Great Atlantic & Pacific Tea Co.

v. Supermarket Equipment Corp., 340 U. S. 147, 152. Such a combi

nation of familiar elements according to known methods is likely to

be obvious when it does no more than yield predictable results. See,

e.g., United States v. Adams, 383 U. S. 39, 50–52. When a work is

available in one field, design incentives and other market forces can

prompt variations of it, either in the same field or in another. If a

person of ordinary skill in the art can implement a predictable varia

tion, and would see the benefit of doing so, §103 likely bars its pat

entability. Moreover, if a technique has been used to improve one

device, and a person of ordinary skill in the art would recognize that

it would improve similar devices in the same way, using the tech

nique is obvious unless its actual application is beyond that person’s

skill. A court must ask whether the improvement is more than the

predictable use of prior-art elements according to their established

functions. Following these principles may be difficult if the claimed

subject matter involves more than the simple substitution of one

known element for another or the mere application of a known tech

nique to a piece of prior art ready for the improvement. To determine

whether there was an apparent reason to combine the known ele

ments in the way a patent claims, it will often be necessary to look to

interrelated teachings of multiple patents; to the effects of demands

known to the design community or present in the marketplace; and to

the background knowledge possessed by a person having ordinary

skill in the art. To facilitate review, this analysis should be made ex

plicit. But it need not seek out precise teachings directed to the chal

lenged claim’s specific subject matter, for a court can consider the in

ferences and creative steps a person of ordinary skill in the art would

employ. Pp. 11–14.

(b) The TSM test captures a helpful insight: A patent composed of

several elements is not proved obvious merely by demonstrating that

each element was, independently, known in the prior art. Although

common sense directs caution as to a patent application claiming as

Cite as: 550 U. S. ____ (2007) 5

Syllabus

innovation the combination of two known devices according to their

established functions, it can be important to identify a reason that

would have prompted a person of ordinary skill in the art to combine

the elements as the new invention does. Inventions usually rely

upon building blocks long since uncovered, and claimed discoveries

almost necessarily will be combinations of what, in some sense, is al

ready known. Helpful insights, however, need not become rigid and

mandatory formulas. If it is so applied, the TSM test is incompatible

with this Court’s precedents. The diversity of inventive pursuits and

of modern technology counsels against confining the obviousness

analysis by a formalistic conception of the words teaching, sugges

tion, and motivation, or by overemphasizing the importance of pub

lished articles and the explicit content of issued patents. In many

fields there may be little discussion of obvious techniques or combina

tions, and market demand, rather than scientific literature, may of

ten drive design trends. Granting patent protection to advances that

would occur in the ordinary course without real innovation retards

progress and may, for patents combining previously known elements,

deprive prior inventions of their value or utility. Since the TSM test

was devised, the Federal Circuit doubtless has applied it in accord

with these principles in many cases. There is no necessary inconsis

tency between the test and the Graham analysis. But a court errs

where, as here, it transforms general principle into a rigid rule limit

ing the obviousness inquiry. Pp. 14–15.

(c) The flaws in the Federal Circuit’s analysis relate mostly to its

narrow conception of the obviousness inquiry consequent in its appli

cation of the TSM test. The Circuit first erred in holding that courts

and patent examiners should look only to the problem the patentee

was trying to solve. Under the correct analysis, any need or problem

known in the field and addressed by the patent can provide a reason

for combining the elements in the manner claimed. Second, the ap

peals court erred in assuming that a person of ordinary skill in the

art attempting to solve a problem will be led only to those prior art

elements designed to solve the same problem. The court wrongly

concluded that because Asano’s primary purpose was solving the con

stant ratio problem, an inventor considering how to put a sensor on

an adjustable pedal would have no reason to consider putting it on

the Asano pedal. It is common sense that familiar items may have

obvious uses beyond their primary purposes, and a person of ordinary

skill often will be able to fit the teachings of multiple patents to

gether like pieces of a puzzle. Regardless of Asano’s primary pur

pose, it provided an obvious example of an adjustable pedal with a

fixed pivot point, and the prior art was replete with patents indicat

ing that such a point was an ideal mount for a sensor. Third, the

6 KSR INT’L CO. v. TELEFLEX INC.

Syllabus

court erred in concluding that a patent claim cannot be proved obvi

ous merely by showing that the combination of elements was obvious

to try. When there is a design need or market pressure to solve a

problem and there are a finite number of identified, predictable solu

tions, a person of ordinary skill in the art has good reason to pursue

the known options within his or her technical grasp. If this leads to

the anticipated success, it is likely the product not of innovation but

of ordinary skill and common sense. Finally, the court drew the

wrong conclusion from the risk of courts and patent examiners falling

prey to hindsight bias. Rigid preventative rules that deny recourse to

common sense are neither necessary under, nor consistent with, this

Court’s case law. Pp. 15–18.

2. Application of the foregoing standards demonstrates that claim 4

is obvious. Pp. 18–23.

(a) The Court rejects Teleflex’s argument that the Asano pivot

mechanism’s design prevents its combination with a sensor in the

manner claim 4 describes. This argument was not raised before the

District Court, and it is unclear whether it was raised before the

Federal Circuit. Given the significance of the District Court’s finding

that combining Asano with a pivot-mounted pedal position sensor fell

within claim 4’s scope, it is apparent that Teleflex would have made

clearer challenges if it intended to preserve this claim. Its failure to

clearly raise the argument, and the appeals court’s silence on the is

sue, lead this Court to accept the District Court’s conclusion. Pp. 18–

20.

(b) The District Court correctly concluded that when Engelgau

designed the claim 4 subject matter, it was obvious to a person of or

dinary skill in the art to combine Asano with a pivot-mounted pedal

position sensor. There then was a marketplace creating a strong in

centive to convert mechanical pedals to electronic pedals, and the

prior art taught a number of methods for doing so. The Federal Cir

cuit considered the issue too narrowly by, in effect, asking whether a

pedal designer writing on a blank slate would have chosen both

Asano and a modular sensor similar to the ones used in the Chevrolet

trucks and disclosed in the ’068 patent. The proper question was

whether a pedal designer of ordinary skill in the art, facing the wide

range of needs created by developments in the field, would have seen

an obvious benefit to upgrading Asano with a sensor. For such a de

signer starting with Asano, the question was where to attach the

sensor. The ’936 patent taught the utility of putting the sensor on

the pedal device. Smith, in turn, explained not to put the sensor on

the pedal footpad, but instead on the structure. And from Rixon’s

known wire-chafing problems, and Smith’s teaching that the pedal

assemblies must not precipitate any motion in the connecting wires,

Cite as: 550 U. S. ____ (2007) 7

Syllabus

the designer would know to place the sensor on a nonmoving part of

the pedal structure. The most obvious such point is a pivot point.

The designer, accordingly, would follow Smith in mounting the sensor

there. Just as it was possible to begin with the objective to upgrade

Asano to work with a computer-controlled throttle, so too was it pos

sible to take an adjustable electronic pedal like Rixon and seek an

improvement that would avoid the wire-chafing problem. Teleflex

has not shown anything in the prior art that taught away from the

use of Asano, nor any secondary factors to dislodge the determination

that claim 4 is obvious. Pp. 20–23.

3. The Court disagrees with the Federal Circuit’s holding that

genuine issues of material fact precluded summary judgment. The

ultimate judgment of obviousness is a legal determination. Graham,

383 U. S., at 17. Where, as here, the prior art’s content, the patent

claim’s scope, and the level of ordinary skill in the art are not in ma

terial dispute and the claim’s obviousness is apparent, summary

judgment is appropriate. P. 23.

119 Fed. Appx. 282, reversed and remanded.

KENNEDY, J., delivered the opinion for a unanimous Court.

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, Wash

ington, D. C. 20543, of any typographical or other formal errors, in order

that corrections may be made before the preliminary print goes to press.

SUPREME COURT OF THE UNITED STATES

_________________

No. 04–1350

_________________

KSR INTERNATIONAL CO., PETITIONER v.

TELEFLEX INC. ET AL.

ON WRIT OF CERTIORARI TO THE UNITED STATES COURT OF

APPEALS FOR THE FEDERAL CIRCUIT

[April 30, 2007]

JUSTICE KENNEDY delivered the opinion of the Court.

Teleflex Incorporated and its subsidiary Technology

Holding Company—both referred to here as Teleflex—

sued KSR International Company for patent infringement.

The patent at issue, United States Patent No. 6,237,565

B1, is entitled “Adjustable Pedal Assembly With Elec

tronic Throttle Control.” Supplemental App. 1. The pat

entee is Steven J. Engelgau, and the patent is referred to

as “the Engelgau patent.” Teleflex holds the exclusive

license to the patent.

Claim 4 of the Engelgau patent describes a mechanism

for combining an electronic sensor with an adjustable

automobile pedal so the pedal’s position can be transmit

ted to a computer that controls the throttle in the vehicle’s

engine. When Teleflex accused KSR of infringing the

Engelgau patent by adding an electronic sensor to one of

KSR’s previously designed pedals, KSR countered that

claim 4 was invalid under the Patent Act, 35 U. S. C. §103,

because its subject matter was obvious.

Section 103 forbids issuance of a patent when “the

differences between the subject matter sought to be pat

2 KSR INT’L CO. v. TELEFLEX INC.

Opinion of the Court

ented and the prior art are such that the subject matter as

a whole would have been obvious at the time the invention

was made to a person having ordinary skill in the art to

which said subject matter pertains.”

In Graham v. John Deere Co. of Kansas City, 383 U. S. 1

(1966), the Court set out a framework for applying the

statutory language of §103, language itself based on the

logic of the earlier decision in Hotchkiss v. Greenwood, 11

How. 248 (1851), and its progeny. See 383 U. S., at 15–17.

The analysis is objective:

“Under §103, the scope and content of the prior art are

to be determined; differences between the prior art

and the claims at issue are to be ascertained; and the

level of ordinary skill in the pertinent art resolved.

Against this background the obviousness or nonobvi

ousness of the subject matter is determined. Such

secondary considerations as commercial success, long

felt but unsolved needs, failure of others, etc., might

be utilized to give light to the circumstances sur

rounding the origin of the subject matter sought to be

patented.” Id., at 17–18.

While the sequence of these questions might be reordered

in any particular case, the factors continue to define the

inquiry that controls. If a court, or patent examiner,

conducts this analysis and concludes the claimed subject

matter was obvious, the claim is invalid under §103.

Seeking to resolve the question of obviousness with

more uniformity and consistency, the Court of Appeals for

the Federal Circuit has employed an approach referred to

by the parties as the “teaching, suggestion, or motivation”

test (TSM test), under which a patent claim is only proved

obvious if “some motivation or suggestion to combine the

prior art teachings” can be found in the prior art, the

nature of the problem, or the knowledge of a person hav

ing ordinary skill in the art. See, e.g., Al-Site Corp. v. VSI

Cite as: 550 U. S. ____ (2007) 3

Opinion of the Court

Int’l, Inc., 174 F. 3d 1308, 1323–1324 (CA Fed. 1999).

KSR challenges that test, or at least its application in this

case. See 119 Fed. Appx. 282, 286–290 (CA Fed. 2005).

Because the Court of Appeals addressed the question of

obviousness in a manner contrary to §103 and our prece

dents, we granted certiorari, 547 U. S ___ (2006). We now

reverse.

I

A

In car engines without computer-controlled throttles,

the accelerator pedal interacts with the throttle via cable

or other mechanical link. The pedal arm acts as a lever

rotating around a pivot point. In a cable-actuated throttle

control the rotation caused by pushing down the pedal

pulls a cable, which in turn pulls open valves in the carbu

retor or fuel injection unit. The wider the valves open, the

more fuel and air are released, causing combustion to

increase and the car to accelerate. When the driver takes

his foot off the pedal, the opposite occurs as the cable is

released and the valves slide closed.

In the 1990’s it became more common to install com

puters in cars to control engine operation. Computer-

controlled throttles open and close valves in response to

electronic signals, not through force transferred from the

pedal by a mechanical link. Constant, delicate adjust

ments of air and fuel mixture are possible. The computer’s

rapid processing of factors beyond the pedal’s position

improves fuel efficiency and engine performance.

For a computer-controlled throttle to respond to a

driver’s operation of the car, the computer must know

what is happening with the pedal. A cable or mechanical

link does not suffice for this purpose; at some point, an

electronic sensor is necessary to translate the mechanical

operation into digital data the computer can understand.

Before discussing sensors further we turn to the me

4 KSR INT’L CO. v. TELEFLEX INC.

Opinion of the Court

chanical design of the pedal itself. In the traditional

design a pedal can be pushed down or released but cannot

have its position in the footwell adjusted by sliding the

pedal forward or back. As a result, a driver who wishes to

be closer or farther from the pedal must either reposition

himself in the driver’s seat or move the seat in some way.

In cars with deep footwells these are imperfect solutions

for drivers of smaller stature. To solve the problem, in

ventors, beginning in the 1970’s, designed pedals that

could be adjusted to change their location in the footwell.

Important for this case are two adjustable pedals disclosed

in U. S. Patent Nos. 5,010,782 (filed July 28, 1989) (Asano)

and 5,460,061 (filed Sept. 17, 1993) (Redding). The Asano

patent reveals a support structure that houses the pedal

so that even when the pedal location is adjusted relative to

the driver, one of the pedal’s pivot points stays fixed. The

pedal is also designed so that the force necessary to push

the pedal down is the same regardless of adjustments to

its location. The Redding patent reveals a different, slid

ing mechanism where both the pedal and the pivot point

are adjusted.

We return to sensors. Well before Engelgau applied for

his challenged patent, some inventors had obtained pat

ents involving electronic pedal sensors for computer-

controlled throttles. These inventions, such as the device

disclosed in U. S. Patent No. 5,241,936 (filed Sept. 9, 1991)

(’936), taught that it was preferable to detect the pedal’s

position in the pedal assembly, not in the engine. The ’936

patent disclosed a pedal with an electronic sensor on a

pivot point in the pedal assembly. U. S. Patent No.

5,063,811 (filed July 9, 1990) (Smith) taught that to pre

vent the wires connecting the sensor to the computer from

chafing and wearing out, and to avoid grime and damage

from the driver’s foot, the sensor should be put on a fixed

part of the pedal assembly rather than in or on the pedal’s

footpad.

Cite as: 550 U. S. ____ (2007) 5

Opinion of the Court

In addition to patents for pedals with integrated sensors

inventors obtained patents for self-contained modular

sensors. A modular sensor is designed independently of a

given pedal so that it can be taken off the shelf and at

tached to mechanical pedals of various sorts, enabling the

pedals to be used in automobiles with computer-controlled

throttles. One such sensor was disclosed in U. S. Patent

No. 5,385,068 (filed Dec. 18, 1992) (’068). In 1994, Chevro

let manufactured a line of trucks using modular sensors

“attached to the pedal support bracket, adjacent to the

pedal and engaged with the pivot shaft about which the

pedal rotates in operation.” 298 F. Supp. 2d 581, 589 (ED

Mich. 2003).

The prior art contained patents involving the placement

of sensors on adjustable pedals as well. For example, U. S.

Patent No. 5,819,593 (filed Aug. 17, 1995) (Rixon) dis

closes an adjustable pedal assembly with an electronic

sensor for detecting the pedal’s position. In the Rixon

pedal the sensor is located in the pedal footpad. The Rixon

pedal was known to suffer from wire chafing when the

pedal was depressed and released.

This short account of pedal and sensor technology leads

to the instant case.

B

KSR, a Canadian company, manufactures and supplies

auto parts, including pedal systems. Ford Motor Company

hired KSR in 1998 to supply an adjustable pedal system

for various lines of automobiles with cable-actuated throt

tle controls. KSR developed an adjustable mechanical

pedal for Ford and obtained U. S. Patent No. 6,151,976

(filed July 16, 1999) (’976) for the design. In 2000, KSR

was chosen by General Motors Corporation (GMC or GM)

to supply adjustable pedal systems for Chevrolet and GMC

light trucks that used engines with computer-controlled

throttles. To make the ’976 pedal compatible with the

6 KSR INT’L CO. v. TELEFLEX INC.

Opinion of the Court

trucks, KSR merely took that design and added a modular

sensor.

Teleflex is a rival to KSR in the design and manufacture

of adjustable pedals. As noted, it is the exclusive licensee

of the Engelgau patent. Engelgau filed the patent applica

tion on August 22, 2000 as a continuation of a previous

application for U. S. Patent No. 6,109,241, which was filed

on January 26, 1999. He has sworn he invented the pat

ent’s subject matter on February 14, 1998. The Engelgau

patent discloses an adjustable electronic pedal described

in the specification as a “simplified vehicle control pedal

assembly that is less expensive, and which uses fewer

parts and is easier to package within the vehicle.” Engel

gau, col. 2, lines 2–5, Supplemental App. 6. Claim 4 of the

patent, at issue here, describes:

“A vehicle control pedal apparatus comprising:

a support adapted to be mounted to a vehicle struc

ture;

an adjustable pedal assembly having a pedal arm

moveable in for[e] and aft directions with respect to

said support;

a pivot for pivotally supporting said adjustable pedal

assembly with respect to said support and defining a

pivot axis; and

an electronic control attached to said support for con

trolling a vehicle system;

said apparatus characterized by said electronic control

being responsive to said pivot for providing a signal

that corresponds to pedal arm position as said pedal

arm pivots about said pivot axis between rest and ap

plied positions wherein the position of said pivot re

mains constant while said pedal arm moves in fore

and aft directions with respect to said pivot.” Id., col.

Cite as: 550 U. S. ____ (2007) 7

Opinion of the Court

6, lines 17–36, Supplemental App. 8 (diagram num

bers omitted).

We agree with the District Court that the claim discloses

“a position-adjustable pedal assembly with an electronic

pedal position sensor attached to the support member of

the pedal assembly. Attaching the sensor to the support

member allows the sensor to remain in a fixed position

while the driver adjusts the pedal.” 298 F. Supp. 2d, at

586–587.

Before issuing the Engelgau patent the U. S. Patent and

Trademark Office (PTO) rejected one of the patent claims

that was similar to, but broader than, the present claim 4.

The claim did not include the requirement that the sensor

be placed on a fixed pivot point. The PTO concluded the

claim was an obvious combination of the prior art dis

closed in Redding and Smith, explaining:

“ ‘Since the prior ar[t] references are from the field of

endeavor, the purpose disclosed . . . would have been

recognized in the pertinent art of Redding. Therefore

it would have been obvious . . . to provide the device of

Redding with the . . . means attached to a support

member as taught by Smith.’ ” Id., at 595.

In other words Redding provided an example of an adjust

able pedal and Smith explained how to mount a sensor on

a pedal’s support structure, and the rejected patent claim

merely put these two teachings together.

Although the broader claim was rejected, claim 4 was

later allowed because it included the limitation of a fixed

pivot point, which distinguished the design from Red

ding’s. Ibid. Engelgau had not included Asano among the

prior art references, and Asano was not mentioned in the

patent’s prosecution. Thus, the PTO did not have before it

an adjustable pedal with a fixed pivot point. The patent

issued on May 29, 2001 and was assigned to Teleflex.

Upon learning of KSR’s design for GM, Teleflex sent a

8 KSR INT’L CO. v. TELEFLEX INC.

Opinion of the Court

warning letter informing KSR that its proposal would

violate the Engelgau patent. “ ‘Teleflex believes that any

supplier of a product that combines an adjustable pedal

with an electronic throttle control necessarily employs

technology covered by one or more’ ” of Teleflex’s patents.

Id., at 585. KSR refused to enter a royalty arrangement

with Teleflex; so Teleflex sued for infringement, asserting

KSR’s pedal infringed the Engelgau patent and two other

patents. Ibid. Teleflex later abandoned its claims regard

ing the other patents and dedicated the patents to the

public. The remaining contention was that KSR’s pedal

system for GM infringed claim 4 of the Engelgau patent.

Teleflex has not argued that the other three claims of the

patent are infringed by KSR’s pedal, nor has Teleflex

argued that the mechanical adjustable pedal designed by

KSR for Ford infringed any of its patents.

C

The District Court granted summary judgment in KSR’s

favor. After reviewing the pertinent history of pedal

design, the scope of the Engelgau patent, and the relevant

prior art, the court considered the validity of the contested

claim. By direction of 35 U. S. C. §282, an issued patent is

presumed valid. The District Court applied Graham’s

framework to determine whether under summary-

judgment standards KSR had overcome the presumption

and demonstrated that claim 4 was obvious in light of the

prior art in existence when the claimed subject matter was

invented. See §102(a).

The District Court determined, in light of the expert

testimony and the parties’ stipulations, that the level of

ordinary skill in pedal design was “ ‘an undergraduate

degree in mechanical engineering (or an equivalent

amount of industry experience) [and] familiarity with

pedal control systems for vehicles.’ ” 298 F. Supp. 2d, at

590. The court then set forth the relevant prior art, in

Cite as: 550 U. S. ____ (2007) 9

Opinion of the Court

cluding the patents and pedal designs described above.

Following Graham’s direction, the court compared the

teachings of the prior art to the claims of Engelgau. It

found “little difference.” 298 F. Supp. 2d, at 590. Asano

taught everything contained in claim 4 except the use of a

sensor to detect the pedal’s position and transmit it to the

computer controlling the throttle. That additional aspect

was revealed in sources such as the ’068 patent and the

sensors used by Chevrolet.

Under the controlling cases from the Court of Appeals

for the Federal Circuit, however, the District Court was

not permitted to stop there. The court was required also

to apply the TSM test. The District Court held KSR had

satisfied the test. It reasoned (1) the state of the industry

would lead inevitably to combinations of electronic sensors

and adjustable pedals, (2) Rixon provided the basis for

these developments, and (3) Smith taught a solution to the

wire chafing problems in Rixon, namely locating the sen

sor on the fixed structure of the pedal. This could lead to

the combination of Asano, or a pedal like it, with a pedal

position sensor.

The conclusion that the Engelgau design was obvious

was supported, in the District Court’s view, by the PTO’s

rejection of the broader version of claim 4. Had Engelgau

included Asano in his patent application, it reasoned, the

PTO would have found claim 4 to be an obvious combina

tion of Asano and Smith, as it had found the broader

version an obvious combination of Redding and Smith. As

a final matter, the District Court held that the secondary

factor of Teleflex’s commercial success with pedals based

on Engelgau’s design did not alter its conclusion. The

District Court granted summary judgment for KSR.

With principal reliance on the TSM test, the Court of

Appeals reversed. It ruled the District Court had not been

strict enough in applying the test, having failed to make

“ ‘finding[s] as to the specific understanding or principle

10 KSR INT’L CO. v. TELEFLEX INC.

Opinion of the Court

within the knowledge of a skilled artisan that would have

motivated one with no knowledge of [the] invention’ . . . to

attach an electronic control to the support bracket of the

Asano assembly.” 119 Fed. Appx., at 288 (brackets in

original) (quoting In re Kotzab, 217 F. 3d 1365, 1371 (CA

Fed. 2000)). The Court of Appeals held that the District

Court was incorrect that the nature of the problem to be

solved satisfied this requirement because unless the “prior

art references address[ed] the precise problem that the

patentee was trying to solve,” the problem would not

motivate an inventor to look at those references. 119 Fed.

Appx., at 288.

Here, the Court of Appeals found, the Asano pedal was

designed to solve the “ ‘constant ratio problem’ ”—that is,

to ensure that the force required to depress the pedal is

the same no matter how the pedal is adjusted—whereas

Engelgau sought to provide a simpler, smaller, cheaper

adjustable electronic pedal. Ibid. As for Rixon, the court

explained, that pedal suffered from the problem of wire

chafing but was not designed to solve it. In the court’s

view Rixon did not teach anything helpful to Engelgau’s

purpose. Smith, in turn, did not relate to adjustable ped

als and did not “necessarily go to the issue of motivation to

attach the electronic control on the support bracket of the

pedal assembly.” Ibid. When the patents were inter

preted in this way, the Court of Appeals held, they would

not have led a person of ordinary skill to put a sensor on

the sort of pedal described in Asano.

That it might have been obvious to try the combination

of Asano and a sensor was likewise irrelevant, in the

court’s view, because “ ‘ “[o]bvious to try” has long been

held not to constitute obviousness.’ ” Id., at 289 (quoting

In re Deuel, 51 F. 3d 1552, 1559 (CA Fed. 1995)).

The Court of Appeals also faulted the District Court’s

consideration of the PTO’s rejection of the broader version

of claim 4. The District Court’s role, the Court of Appeals

Cite as: 550 U. S. ____ (2007) 11

Opinion of the Court

explained, was not to speculate regarding what the PTO

might have done had the Engelgau patent mentioned

Asano. Rather, the court held, the District Court was

obliged first to presume that the issued patent was valid

and then to render its own independent judgment of obvi

ousness based on a review of the prior art. The fact that

the PTO had rejected the broader version of claim 4, the

Court of Appeals said, had no place in that analysis.

The Court of Appeals further held that genuine issues of

material fact precluded summary judgment. Teleflex had

proffered statements from one expert that claim 4 “ ‘was a

simple, elegant, and novel combination of features,’ ” 119

Fed. Appx., at 290, compared to Rixon, and from another

expert that claim 4 was nonobvious because, unlike in

Rixon, the sensor was mounted on the support bracket

rather than the pedal itself. This evidence, the court

concluded, sufficed to require a trial.

II

A

We begin by rejecting the rigid approach of the Court of

Appeals. Throughout this Court’s engagement with the

question of obviousness, our cases have set forth an ex

pansive and flexible approach inconsistent with the way

the Court of Appeals applied its TSM test here. To be

sure, Graham recognized the need for “uniformity and

definiteness.” 383 U. S., at 18. Yet the principles laid

down in Graham reaffirmed the “functional approach” of

Hotchkiss, 11 How. 248. See 383 U. S., at 12. To this end,

Graham set forth a broad inquiry and invited courts,

where appropriate, to look at any secondary considera

tions that would prove instructive. Id., at 17.

Neither the enactment of §103 nor the analysis in Gra

ham disturbed this Court’s earlier instructions concerning

the need for caution in granting a patent based on the

combination of elements found in the prior art. For over a

12 KSR INT’L CO. v. TELEFLEX INC.

Opinion of the Court

half century, the Court has held that a “patent for a com

bination which only unites old elements with no change in

their respective functions . . . obviously withdraws what is

already known into the field of its monopoly and dimin

ishes the resources available to skillful men.” Great At

lantic & Pacific Tea Co. v. Supermarket Equipment Corp.,

340 U. S. 147, 152 (1950). This is a principal reason for

declining to allow patents for what is obvious. The combi

nation of familiar elements according to known methods is

likely to be obvious when it does no more than yield pre

dictable results. Three cases decided after Graham illus

trate the application of this doctrine.

In United States v. Adams, 383 U. S. 39, 40 (1966), a

companion case to Graham, the Court considered the

obviousness of a “wet battery” that varied from prior

designs in two ways: It contained water, rather than the

acids conventionally employed in storage batteries; and its

electrodes were magnesium and cuprous chloride, rather

than zinc and silver chloride. The Court recognized that

when a patent claims a structure already known in the

prior art that is altered by the mere substitution of one

element for another known in the field, the combination

must do more than yield a predictable result. 383 U. S., at

50–51. It nevertheless rejected the Government’s claim

that Adams’s battery was obvious. The Court relied upon

the corollary principle that when the prior art teaches

away from combining certain known elements, discovery

of a successful means of combining them is more likely to

be nonobvious. Id., at 51–52. When Adams designed his

battery, the prior art warned that risks were involved in

using the types of electrodes he employed. The fact that

the elements worked together in an unexpected and fruit

ful manner supported the conclusion that Adams’s design

was not obvious to those skilled in the art.

In Anderson’s-Black Rock, Inc. v. Pavement Salvage Co.,

396 U. S. 57 (1969), the Court elaborated on this approach.

Cite as: 550 U. S. ____ (2007) 13

Opinion of the Court

The subject matter of the patent before the Court was a

device combining two pre-existing elements: a radiant-

heat burner and a paving machine. The device, the Court

concluded, did not create some new synergy: The radiant-

heat burner functioned just as a burner was expected to

function; and the paving machine did the same. The two

in combination did no more than they would in separate,

sequential operation. Id., at 60–62. In those circum

stances, “while the combination of old elements performed

a useful function, it added nothing to the nature and

quality of the radiant-heat burner already patented,” and

the patent failed under §103. Id., at 62 (footnote omitted).

Finally, in Sakraida v. AG Pro, Inc., 425 U. S. 273

(1976), the Court derived from the precedents the conclu

sion that when a patent “simply arranges old elements

with each performing the same function it had been

known to perform” and yields no more than one would

expect from such an arrangement, the combination is

obvious. Id., at 282.

The principles underlying these cases are instructive

when the question is whether a patent claiming the com

bination of elements of prior art is obvious. When a work

is available in one field of endeavor, design incentives and

other market forces can prompt variations of it, either in

the same field or a different one. If a person of ordinary

skill can implement a predictable variation, §103 likely

bars its patentability. For the same reason, if a technique

has been used to improve one device, and a person of

ordinary skill in the art would recognize that it would

improve similar devices in the same way, using the tech

nique is obvious unless its actual application is beyond his

or her skill. Sakraida and Anderson’s-Black Rock are

illustrative—a court must ask whether the improvement

is more than the predictable use of prior art elements

according to their established functions.

Following these principles may be more difficult in other

14 KSR INT’L CO. v. TELEFLEX INC.

Opinion of the Court

cases than it is here because the claimed subject matter

may involve more than the simple substitution of one

known element for another or the mere application of a

known technique to a piece of prior art ready for the im

provement. Often, it will be necessary for a court to look

to interrelated teachings of multiple patents; the effects of

demands known to the design community or present in the

marketplace; and the background knowledge possessed by

a person having ordinary skill in the art, all in order to

determine whether there was an apparent reason to com

bine the known elements in the fashion claimed by the

patent at issue. To facilitate review, this analysis should

be made explicit. See In re Kahn, 441 F. 3d 977, 988 (CA

Fed. 2006) (“[R]ejections on obviousness grounds cannot be

sustained by mere conclusory statements; instead, there

must be some articulated reasoning with some rational

underpinning to support the legal conclusion of obvious

ness”). As our precedents make clear, however, the analy

sis need not seek out precise teachings directed to the

specific subject matter of the challenged claim, for a court

can take account of the inferences and creative steps that

a person of ordinary skill in the art would employ.

B

When it first established the requirement of demon

strating a teaching, suggestion, or motivation to combine

known elements in order to show that the combination is

obvious, the Court of Customs and Patent Appeals cap

tured a helpful insight. See Application of Bergel, 292

F. 2d 955, 956–957 (1961). As is clear from cases such as

Adams, a patent composed of several elements is not

proved obvious merely by demonstrating that each of its

elements was, independently, known in the prior art.

Although common sense directs one to look with care at a

patent application that claims as innovation the combina

tion of two known devices according to their established

Cite as: 550 U. S. ____ (2007) 15

Opinion of the Court

functions, it can be important to identify a reason that

would have prompted a person of ordinary skill in the

relevant field to combine the elements in the way the

claimed new invention does. This is so because inventions

in most, if not all, instances rely upon building blocks long

since uncovered, and claimed discoveries almost of neces

sity will be combinations of what, in some sense, is already

known.

Helpful insights, however, need not become rigid and

mandatory formulas; and when it is so applied, the TSM

test is incompatible with our precedents. The obviousness

analysis cannot be confined by a formalistic conception of

the words teaching, suggestion, and motivation, or by

overemphasis on the importance of published articles and

the explicit content of issued patents. The diversity of

inventive pursuits and of modern technology counsels

against limiting the analysis in this way. In many fields it

may be that there is little discussion of obvious techniques

or combinations, and it often may be the case that market

demand, rather than scientific literature, will drive design

trends. Granting patent protection to advances that

would occur in the ordinary course without real innovation

retards progress and may, in the case of patents combin

ing previously known elements, deprive prior inventions of

their value or utility.

In the years since the Court of Customs and Patent

Appeals set forth the essence of the TSM test, the Court of

Appeals no doubt has applied the test in accord with these

principles in many cases. There is no necessary inconsis

tency between the idea underlying the TSM test and the

Graham analysis. But when a court transforms the gen

eral principle into a rigid rule that limits the obviousness

inquiry, as the Court of Appeals did here, it errs.

C

The flaws in the analysis of the Court of Appeals relate

16 KSR INT’L CO. v. TELEFLEX INC.

Opinion of the Court

for the most part to the court’s narrow conception of the

obviousness inquiry reflected in its application of the TSM

test. In determining whether the subject matter of a

patent claim is obvious, neither the particular motivation

nor the avowed purpose of the patentee controls. What

matters is the objective reach of the claim. If the claim

extends to what is obvious, it is invalid under §103. One

of the ways in which a patent’s subject matter can be

proved obvious is by noting that there existed at the time

of invention a known problem for which there was an

obvious solution encompassed by the patent’s claims.

The first error of the Court of Appeals in this case was

to foreclose this reasoning by holding that courts and

patent examiners should look only to the problem the

patentee was trying to solve. 119 Fed. Appx., at 288. The

Court of Appeals failed to recognize that the problem

motivating the patentee may be only one of many ad

dressed by the patent’s subject matter. The question is

not whether the combination was obvious to the patentee

but whether the combination was obvious to a person with

ordinary skill in the art. Under the correct analysis, any

need or problem known in the field of endeavor at the time

of invention and addressed by the patent can provide a

reason for combining the elements in the manner claimed.

The second error of the Court of Appeals lay in its as

sumption that a person of ordinary skill attempting to

solve a problem will be led only to those elements of prior

art designed to solve the same problem. Ibid. The pri

mary purpose of Asano was solving the constant ratio

problem; so, the court concluded, an inventor considering

how to put a sensor on an adjustable pedal would have no

reason to consider putting it on the Asano pedal. Ibid.

Common sense teaches, however, that familiar items may

have obvious uses beyond their primary purposes, and in

many cases a person of ordinary skill will be able to fit the

teachings of multiple patents together like pieces of a

Cite as: 550 U. S. ____ (2007) 17

Opinion of the Court

puzzle. Regardless of Asano’s primary purpose, the design

provided an obvious example of an adjustable pedal with a

fixed pivot point; and the prior art was replete with pat

ents indicating that a fixed pivot point was an ideal mount

for a sensor. The idea that a designer hoping to make an

adjustable electronic pedal would ignore Asano because

Asano was designed to solve the constant ratio problem

makes little sense. A person of ordinary skill is also a

person of ordinary creativity, not an automaton.

The same constricted analysis led the Court of Appeals

to conclude, in error, that a patent claim cannot be proved

obvious merely by showing that the combination of ele

ments was “obvious to try.” Id., at 289 (internal quotation

marks omitted). When there is a design need or market

pressure to solve a problem and there are a finite number

of identified, predictable solutions, a person of ordinary

skill has good reason to pursue the known options within

his or her technical grasp. If this leads to the anticipated

success, it is likely the product not of innovation but of

ordinary skill and common sense. In that instance the fact

that a combination was obvious to try might show that it

was obvious under §103.

The Court of Appeals, finally, drew the wrong conclusion

from the risk of courts and patent examiners falling prey

to hindsight bias. A factfinder should be aware, of course,

of the distortion caused by hindsight bias and must be

cautious of arguments reliant upon ex post reasoning. See

Graham, 383 U. S., at 36 (warning against a “temptation

to read into the prior art the teachings of the invention in

issue” and instructing courts to “ ‘guard against slipping

into the use of hindsight’ ” (quoting Monroe Auto Equip

ment Co. v. Heckethorn Mfg. & Supply Co., 332 F. 2d 406,

412 (CA6 1964))). Rigid preventative rules that deny

factfinders recourse to common sense, however, are nei

ther necessary under our case law nor consistent with it.

We note the Court of Appeals has since elaborated a

18 KSR INT’L CO. v. TELEFLEX INC.

Opinion of the Court

broader conception of the TSM test than was applied in

the instant matter. See, e.g., DyStar Textilfarben GmbH

& Co. Deutschland KG v. C. H. Patrick Co., 464 F. 3d

1356, 1367 (2006) (“Our suggestion test is in actuality

quite flexible and not only permits, but requires, consid

eration of common knowledge and common sense”); Alza

Corp. v. Mylan Labs., Inc., 464 F. 3d 1286, 1291 (2006)

(“There is flexibility in our obviousness jurisprudence

because a motivation may be found implicitly in the prior

art. We do not have a rigid test that requires an actual

teaching to combine . . .”). Those decisions, of course, are

not now before us and do not correct the errors of law

made by the Court of Appeals in this case. The extent to

which they may describe an analysis more consistent with

our earlier precedents and our decision here is a matter

for the Court of Appeals to consider in its future cases.

What we hold is that the fundamental misunderstandings

identified above led the Court of Appeals in this case to

apply a test inconsistent with our patent law decisions.

III

When we apply the standards we have explained to the

instant facts, claim 4 must be found obvious. We agree

with and adopt the District Court’s recitation of the rele

vant prior art and its determination of the level of ordi

nary skill in the field. As did the District Court, we see

little difference between the teachings of Asano and Smith

and the adjustable electronic pedal disclosed in claim 4 of

the Engelgau patent. A person having ordinary skill in

the art could have combined Asano with a pedal position

sensor in a fashion encompassed by claim 4, and would

have seen the benefits of doing so.

A

Teleflex argues in passing that the Asano pedal cannot

be combined with a sensor in the manner described by

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

Opinion of the Court

claim 4 because of the design of Asano’s pivot mechanisms.

See Brief for Respondents 48–49, and n. 17. Therefore,

Teleflex reasons, even if adding a sensor to Asano was

obvious, that does not establish that claim 4 encompasses

obvious subject matter. This argument was not, however,

raised before the District Court. There Teleflex was con

tent to assert only that the problem motivating the inven

tion claimed by the Engelgau patent would not lead to the

solution of combining of Asano with a sensor. See Tele

flex’s Response to KSR’s Motion for Summary Judgment of

Invalidity in No. 02–74586 (ED Mich.), pp. 18–20, App.

144a–146a. It is also unclear whether the current argu

ment was raised before the Court of Appeals, where Tele

flex advanced the nonspecific, conclusory contention that

combining Asano with a sensor would not satisfy the

limitations of claim 4. See Brief for Plaintiffs-Appellants

in No. 04–1152 (CA Fed.), pp. 42–44. Teleflex’s own ex

pert declarations, moreover, do not support the point

Teleflex now raises. See Declaration of Clark J. Radcliffe,

Ph.D., Supplemental App. 204–207; Declaration of Timo

thy L. Andresen, id., at 208–210. The only statement in

either declaration that might bear on the argument is

found in the Radcliffe declaration:

“Asano . . . and Rixon . . . are complex mechanical

linkage-based devices that are expensive to produce

and assemble and difficult to package. It is exactly

these difficulties with prior art designs that [Engel

gau] resolves. The use of an adjustable pedal with a

single pivot reflecting pedal position combined with an

electronic control mounted between the support and

the adjustment assembly at that pivot was a simple,

elegant, and novel combination of features in the

Engelgau ’565 patent.” Id., at 206, ¶16.

Read in the context of the declaration as a whole this is

best interpreted to mean that Asano could not be used to

20 KSR INT’L CO. v. TELEFLEX INC.

Opinion of the Court

solve “[t]he problem addressed by Engelgau ’565[:] to

provide a less expensive, more quickly assembled, and

smaller package adjustable pedal assembly with electronic

control.” Id., at 205, ¶10.

The District Court found that combining Asano with a

pivot-mounted pedal position sensor fell within the scope

of claim 4. 298 F. Supp. 2d, at 592–593. Given the sigifi

cance of that finding to the District Court’s judgment, it is

apparent that Teleflex would have made clearer chal

lenges to it if it intended to preserve this claim. In light of

Teleflex’s failure to raise the argument in a clear fashion,

and the silence of the Court of Appeals on the issue, we

take the District Court’s conclusion on the point to be

correct.

B

The District Court was correct to conclude that, as of the

time Engelgau designed the subject matter in claim 4, it

was obvious to a person of ordinary skill to combine Asano

with a pivot-mounted pedal position sensor. There then

existed a marketplace that created a strong incentive to

convert mechanical pedals to electronic pedals, and the

prior art taught a number of methods for achieving this

advance. The Court of Appeals considered the issue too

narrowly by, in effect, asking whether a pedal designer

writing on a blank slate would have chosen both Asano

and a modular sensor similar to the ones used in the

Chevrolet truckline and disclosed in the ’068 patent. The

District Court employed this narrow inquiry as well,

though it reached the correct result nevertheless. The

proper question to have asked was whether a pedal de

signer of ordinary skill, facing the wide range of needs

created by developments in the field of endeavor, would

have seen a benefit to upgrading Asano with a sensor.

In automotive design, as in many other fields, the inter

action of multiple components means that changing one

Cite as: 550 U. S. ____ (2007) 21

Opinion of the Court

component often requires the others to be modified as

well. Technological developments made it clear that

engines using computer-controlled throttles would become

standard. As a result, designers might have decided to

design new pedals from scratch; but they also would have

had reason to make pre-existing pedals work with the new

engines. Indeed, upgrading its own pre-existing model led

KSR to design the pedal now accused of infringing the

Engelgau patent.

For a designer starting with Asano, the question was

where to attach the sensor. The consequent legal ques

tion, then, is whether a pedal designer of ordinary skill

starting with Asano would have found it obvious to put the

sensor on a fixed pivot point. The prior art discussed

above leads us to the conclusion that attaching the sensor

where both KSR and Engelgau put it would have been

obvious to a person of ordinary skill.

The ’936 patent taught the utility of putting the sensor

on the pedal device, not in the engine. Smith, in turn,

explained to put the sensor not on the pedal’s footpad but

instead on its support structure. And from the known

wire-chafing problems of Rixon, and Smith’s teaching that

“the pedal assemblies must not precipitate any motion in

the connecting wires,” Smith, col. 1, lines 35–37, Supple

mental App. 274, the designer would know to place the

sensor on a nonmoving part of the pedal structure. The

most obvious nonmoving point on the structure from

which a sensor can easily detect the pedal’s position is a

pivot point. The designer, accordingly, would follow Smith

in mounting the sensor on a pivot, thereby designing an

adjustable electronic pedal covered by claim 4.

Just as it was possible to begin with the objective to

upgrade Asano to work with a computer-controlled throt

tle, so too was it possible to take an adjustable electronic

pedal like Rixon and seek an improvement that would

avoid the wire-chafing problem. Following similar steps to

22 KSR INT’L CO. v. TELEFLEX INC.

Opinion of the Court

those just explained, a designer would learn from Smith to

avoid sensor movement and would come, thereby, to Asano

because Asano disclosed an adjustable pedal with a fixed

pivot.

Teleflex indirectly argues that the prior art taught away

from attaching a sensor to Asano because Asano in its

view is bulky, complex, and expensive. The only evidence

Teleflex marshals in support of this argument, however, is

the Radcliffe declaration, which merely indicates that

Asano would not have solved Engelgau’s goal of making a

small, simple, and inexpensive pedal. What the declara

tion does not indicate is that Asano was somehow so

flawed that there was no reason to upgrade it, or pedals

like it, to be compatible with modern engines. Indeed,

Teleflex’s own declarations refute this conclusion. Dr.

Radcliffe states that Rixon suffered from the same bulk

and complexity as did Asano. See id., at 206. Teleflex’s

other expert, however, explained that Rixon was itself

designed by adding a sensor to a pre-existing mechanical

pedal. See id., at 209. If Rixon’s base pedal was not too

flawed to upgrade, then Dr. Radcliffe’s declaration does

not show Asano was either. Teleflex may have made a

plausible argument that Asano is inefficient as compared

to Engelgau’s preferred embodiment, but to judge Asano

against Engelgau would be to engage in the very hindsight

bias Teleflex rightly urges must be avoided. Accordingly,

Teleflex has not shown anything in the prior art that

taught away from the use of Asano.

Like the District Court, finally, we conclude Teleflex has

shown no secondary factors to dislodge the determination

that claim 4 is obvious. Proper application of Graham and

our other precedents to these facts therefore leads to the

conclusion that claim 4 encompassed obvious subject

matter. As a result, the claim fails to meet the require

ment of §103.

We need not reach the question whether the failure to

Cite as: 550 U. S. ____ (2007) 23

Opinion of the Court

disclose Asano during the prosecution of Engelgau voids

the presumption of validity given to issued patents, for

claim 4 is obvious despite the presumption. We neverthe

less think it appropriate to note that the rationale under

lying the presumption—that the PTO, in its expertise, has

approved the claim—seems much diminished here.

IV

A separate ground the Court of Appeals gave for revers

ing the order for summary judgment was the existence of a

dispute over an issue of material fact. We disagree with

the Court of Appeals on this point as well. To the extent

the court understood the Graham approach to exclude the

possibility of summary judgment when an expert provides

a conclusory affidavit addressing the question of obvious

ness, it misunderstood the role expert testimony plays in

the analysis. In considering summary judgment on that

question the district court can and should take into ac

count expert testimony, which may resolve or keep open

certain questions of fact. That is not the end of the issue,

however. The ultimate judgment of obviousness is a legal

determination. Graham, 383 U. S., at 17. Where, as here,

the content of the prior art, the scope of the patent claim,

and the level of ordinary skill in the art are not in mate

rial dispute, and the obviousness of the claim is apparent

in light of these factors, summary judgment is appropri

ate. Nothing in the declarations proffered by Teleflex

prevented the District Court from reaching the careful

conclusions underlying its order for summary judgment in

this case.

* * *

We build and create by bringing to the tangible and

palpable reality around us new works based on instinct,

simple logic, ordinary inferences, extraordinary ideas, and

sometimes even genius. These advances, once part of our

24 KSR INT’L CO. v. TELEFLEX INC.

Opinion of the Court

shared knowledge, define a new threshold from which

innovation starts once more. And as progress beginning

from higher levels of achievement is expected in the nor

mal course, the results of ordinary innovation are not the

subject of exclusive rights under the patent laws. Were it

otherwise patents might stifle, rather than promote, the

progress of useful arts. See U. S. Const., Art. I, §8, cl. 8.

These premises led to the bar on patents claiming obvious

subject matter established in Hotchkiss and codified in

§103. Application of the bar must not be confined within a

test or formulation too constrained to serve its purpose.

KSR provided convincing evidence that mounting a

modular sensor on a fixed pivot point of the Asano pedal

was a design step well within the grasp of a person of

ordinary skill in the relevant art. Its arguments, and the

record, demonstrate that claim 4 of the Engelgau patent is

obvious. In rejecting the District Court’s rulings, the

Court of Appeals analyzed the issue in a narrow, rigid

manner inconsistent with §103 and our precedents. The

judgment of the Court of Appeals is reversed, and the case

remanded for further proceedings consistent with this

opinion.

It is so ordered.