Obviousness of Species When Prior Art Teaches Genus

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USPTO MPEP › Chapter 2100 - Patentability › MPEP § 2144.08

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Text

[Editor Note: This MPEP section is applicable regardless of whether an

application is examined under the AIA or under pre-AIA law. For applications subject

to the first inventor to file (FITF) provisions of the AIA, the relevant time is

"before the effective filing date of the claimed invention". For applications subject

pre-AIA 35

U.S.C. 102

, the relevant time is "at the time of the

invention". See

MPEP § 2150

et seq. Many of the

court decisions discussed in this section involved applications or patents subject to

pre-AIA 35

U.S.C. 102

. These court decisions may be applicable to

applications and patents subject to

AIA 35 U.S.C. 102

but the

relevant time is before the effective filing date of the claimed invention and not at

the time of the invention.]

EXAMINATION OF CLAIMS DIRECTED TO SPECIES BASED UPON A SINGLE PRIOR ART

REFERENCE

When a single prior art reference which discloses a genus

encompassing the claimed species or subgenus but does not expressly disclose the

particular claimed species or subgenus, Office personnel should attempt to find

additional prior art to show that the differences between the prior art primary

reference and the claimed invention as a whole would have been obvious. Where such

additional prior art is not found, Office personnel should consider the factors

discussed below to determine whether a single reference

35 U.S.C. 103

rejection would be appropriate.

II.

DETERMINE WHETHER THE CLAIMED SPECIES OR SUBGENUS WOULD HAVE BEEN OBVIOUS TO

ONE OF ORDINARY SKILL IN THE PERTINENT ART AT THE RELEVANT TIME

The patentability of a claim to a specific compound, species, or

subgenus embraced by a prior art genus should be analyzed no differently than any

other claim for purposes of

35 U.S.C. 103

. “The section 103

requirement of unobviousness is no different in chemical cases than with respect to

other categories of patentable inventions.”

In re Papesch,

315

F.2d 381, 385, 137 USPQ 43, 47 (CCPA 1963). A determination of patentability under

35 U.S.C

pound, species, or

subgenus embraced by a prior art genus should be analyzed no differently than any

other claim for purposes of

35 U.S.C. 103

. “The section 103

requirement of unobviousness is no different in chemical cases than with respect to

other categories of patentable inventions.”

In re Papesch,

315

F.2d 381, 385, 137 USPQ 43, 47 (CCPA 1963). A determination of patentability under

35 U.S.C.

103

should be made upon the facts of the particular case in

view of the totality of the circumstances. See, e.g.,

In re

Dillon,

919 F.2d 688, 692-93, 16 USPQ2d 1897, 1901 (Fed. Cir. 1990)

(en banc)

. Use of

per se

rules by Office

personnel is improper for determining whether claimed subject matter would have been

obvious under

U.S.C. 103

. See, e.g.,

In re Brouwer,

F.3d 422, 425, 37 USPQ2d 1663, 1666 (Fed. Cir. 1996);

In re

Ochiai,

71 F.3d 1565, 1572, 37 USPQ2d 1127, 1133 (Fed. Cir. 1995);

In re Baird,

16 F.3d 380, 382, 29 USPQ2d 1550, 1552 (Fed. Cir.

1994). The fact that a claimed species or subgenus is encompassed by a prior art

genus is not sufficient by itself to establish a

prima facie

case

of obviousness.

In re Baird,

16 F.3d 380, 382, 29 USPQ2d 1550,

1552 (Fed. Cir. 1994) (“The fact that a claimed compound may be encompassed by a

disclosed generic formula does not by itself render that compound obvious.”);

In re Jones,

958 F.2d 347, 350, 21 USPQ2d 1941, 1943 (Fed. Cir.

1992) (Federal Circuit has “decline[d] to extract from

Merck

[

& Co. v. Biocraft Laboratories Inc.,

874 F.2d 804, 10

USPQ2d 1843 (Fed. Cir. 1989)] the rule that... regardless of how broad, a disclosure

of a chemical genus renders obvious any species that happens to fall within it.”).

Establishing a Prima Facie Case of Obviousness

Office personnel must consider the factors set out by the Supreme

Court in

Graham v. John Deere,

383 U.S. 1, 148 USPQ 459 (1966)

in order to establish a

prima facie

case of obviousness. See,

e.g.,

In re Bell,

991 F.2d 781, 783, 26 USPQ2d 1529, 1531 (Fed.

Cir

sclosure

of a chemical genus renders obvious any species that happens to fall within it.”).

Establishing a Prima Facie Case of Obviousness

Office personnel must consider the factors set out by the Supreme

Court in

Graham v. John Deere,

383 U.S. 1, 148 USPQ 459 (1966)

in order to establish a

prima facie

case of obviousness. See,

e.g.,

In re Bell,

991 F.2d 781, 783, 26 USPQ2d 1529, 1531 (Fed.

Cir. 1993) (“The PTO bears the burden of establishing a case of

prima

facie

obviousness.”);

In re Rijckaert,

9 F.3d

1531, 1532, 28 USPQ2d 1955, 1956 (Fed. Cir. 1993);

In re

Oetiker,

977 F.2d 1443, 1445, 24 USPQ2d 1443, 1444 (Fed. Cir. 1992).

Graham

at 17-18, 148 USPQ at 467 requires that to make out a

case of obviousness, one must:

(A) determine the scope and contents of the prior art;

(B) ascertain the differences between the prior art and the

claims in issue;

and

(D) evaluate any evidence of secondary considerations.

If a

prima facie

case is established, the

burden shifts to applicant to come forward with rebuttal evidence or argument to

overcome the

prima facie

case. See, e.g.,

Bell,

991 F.2d at 783-84, 26 USPQ2d at 1531;

Rijckaert,

9 F.3d at 1532, 28 USPQ2d at 1956;

Oetiker,

977 F.2d at 1445, 24 USPQ2d at 1444. Office

personnel should evaluate, when appropriate, the totality of the facts and all of

the evidence to determine whether they still support a conclusion that the claimed

invention would have been obvious to one of ordinary skill in the art at the

relevant time. See

Graham,

at 17-18, 148 USPQ at 467. See,

e.g.,

MPEP §§

714.12

714.13

, and

715.09

for

guidance when rebuttal evidence or argument may not be considered.

Determine the Scope and Content of the Prior Art

After construing the claims, Office personnel should determine

the scope and content of the relevant prior art. Each reference to be applied

as the basis for an obviousness rejection must qualify as prior art under

35 U.S.C.

102

(e.g.,

Panduit Corp. v. Dennison Mfg

and

715.09

for

guidance when rebuttal evidence or argument may not be considered.

Determine the Scope and Content of the Prior Art

After construing the claims, Office personnel should determine

the scope and content of the relevant prior art. Each reference to be applied

as the basis for an obviousness rejection must qualify as prior art under

35 U.S.C.

102

(e.g.,

Panduit Corp. v. Dennison Mfg.

Co.,

810 F.2d 1561, 1568, 1 USPQ2d 1593, 1597 (Fed. Cir. 1987)

(“Before answering

Graham’s

‘content’ inquiry, it must be

known whether a patent or publication is in the prior art under

35 U.S.C.

§ 102

.”)) and must also be analogous art to the claimed

invention. See

MPEP § 2141.01(a)

In the case of a prior art reference disclosing a genus,

Office personnel should make findings as to:

(A) the structure of the disclosed prior art genus and that

of any expressly described species or subgenus within the genus;

(B) any physical or chemical properties and utilities

disclosed for the genus, as well as any suggested limitations on the

usefulness of the genus, and any problems alleged to be addressed by the

genus;

(D) the number of species encompassed by the genus taking

into consideration all of the variables possible.

Ascertain the Differences Between the Closest Disclosed Prior Art

Species or Subgenus of Record and the Claimed Species or Subgenus

Once the structure of the disclosed prior art genus and that

of any expressly described species or subgenus within the genus are identified,

Office personnel should compare it to the claimed species or subgenus to

determine the differences. Through this comparison, the closest disclosed

species or subgenus in the prior art reference should be identified and

compared to that claimed

ies or Subgenus

Once the structure of the disclosed prior art genus and that

of any expressly described species or subgenus within the genus are identified,

Office personnel should compare it to the claimed species or subgenus to

determine the differences. Through this comparison, the closest disclosed

species or subgenus in the prior art reference should be identified and

compared to that claimed. Office personnel should make explicit findings on the

similarities and differences between the closest disclosed prior art species or

subgenus of record and the claimed species or subgenus including findings

relating to similarity of structure, properties and utilities. In

Stratoflex, Inc. v. Aeroquip Corp.,

713 F.2d 1530, 1537,

218 USPQ 871, 877 (Fed. Cir. 1983), the court noted that “the question under

35 U.S.C.

§ 103

is not whether the differences [between the claimed

invention and the prior art] would have been obvious” but “whether the claimed

invention

as a whole

would have been obvious.” (emphasis in

original).

Determine the Level of Skill in the Art

Office personnel should evaluate the prior art from the

standpoint of the hypothetical person having ordinary skill in the art at the

time the claimed invention was made. See,

Ryko Mfg. Co. v.

Nu-Star Inc.,

950 F.2d 714, 718, 21 USPQ2d 1053, 1057 (Fed.

Cir. 1991) (“The importance of resolving the level of ordinary skill in the art

lies in the necessity of maintaining objectivity in the obviousness inquiry.”);

Uniroyal Inc. v. Rudkin-Wiley Corp.,

837 F.2d 1044, 1050,

5 USPQ2d 1434, 1438 (Fed. Cir. 1988) (evidence must be viewed from position of

ordinary skill, not of an expert). In most cases, the only facts of record

pertaining to the level of skill in the art will be found within the prior art

reference and a discussion of the level of ordinary skill will not be needed.

See

MPEP §

2141.03

, subsection II. However, any additional

evidence presented by applicant should be evaluated. See

MPEP §§

2141

, subsection II, and

2141.03

subsection III.

kill, not of an expert). In most cases, the only facts of record

pertaining to the level of skill in the art will be found within the prior art

reference and a discussion of the level of ordinary skill will not be needed.

See

MPEP §

2141.03

, subsection II. However, any additional

evidence presented by applicant should be evaluated. See

MPEP §§

2141

, subsection II, and

2141.03

subsection III.

Determine Whether One of Ordinary Skill in the Art Would Have Had a

Reason To Select the Claimed Species or Subgenus

In light of the findings made relating to the

Graham

factors, Office personnel should determine whether

it would have been obvious to one of ordinary skill in the relevant art to make

the claimed invention as a whole, i.e., to select the claimed species or

subgenus from the disclosed prior art genus. To address this key issue, Office

personnel should consider all relevant prior art teachings, focusing on the

following, where present.

(a)

Consider the Size of the Genus

Consider the size of the prior art genus, bearing in mind

that size alone cannot support an obviousness rejection. There is no

absolute correlation between the size of the prior art genus and a

conclusion of obviousness. See, e.g.,

Baird,

16 F.3d at

383, 29 USPQ2d at 1552. Thus, the mere fact that a prior art genus contains

a small number of members does not create a

per se

rule

of obviousness. Even where the genus contains a small number of members, the

disclosed genus may not possess a recognizable class of compounds with

common properties. This is a distinction between an obviousness rejection

and an anticipation rejection. Contrast the obviousness consideration with

an anticipation rejection where it is clear that each member of the small

genus contains common properties. A genus may be so small that, when

considered in light of the totality of the circumstances, it would

anticipate the claimed species or subgenus

ommon properties. This is a distinction between an obviousness rejection

and an anticipation rejection. Contrast the obviousness consideration with

an anticipation rejection where it is clear that each member of the small

genus contains common properties. A genus may be so small that, when

considered in light of the totality of the circumstances, it would

anticipate the claimed species or subgenus. For example, it has been held

that a prior art genus containing only 20 compounds and a limited number of

variations in the generic chemical formula inherently anticipated a claimed

species within the genus because “one skilled in [the] art would... envisage

each member

” of the genus.

In re

Petering,

301 F.2d 676, 681, 133 USPQ 275, 280 (CCPA 1962)

(emphasis in original). More specifically, the court in

Petering

stated:

A simple calculation will show that, excluding

isomerism within certain of the R groups, the limited class we find in

Karrer contains only 20 compounds. However, we wish to point out that it

is not the mere number of compounds in this limited class which is

significant here but, rather, the total circumstances involved, including

such factors as the limited number of variations for R, only two

alternatives for Y and Z, no alternatives for the other ring positions,

and a large unchanging parent structural nucleus. With these

circumstances in mind, it is our opinion that Karrer has described to

those with ordinary skill in this art each of the various permutations

here involved as fully as if he had drawn each structural formula or had

written each name.

Id.

(emphasis in original).

Accord In re

Schaumann,

572 F.2d 312, 316, 197 USPQ 5, 9 (CCPA 1978) (prior

art genus encompassing claimed species which disclosed preference for lower

alkyl secondary amines, as well as properties possessed by the claimed

compound constituted description of claimed compound for purposes of

pre-AIA

35 U.S.C. 102(b)

)

awn each structural formula or had

written each name.

Id.

(emphasis in original).

Accord In re

Schaumann,

572 F.2d 312, 316, 197 USPQ 5, 9 (CCPA 1978) (prior

art genus encompassing claimed species which disclosed preference for lower

alkyl secondary amines, as well as properties possessed by the claimed

compound constituted description of claimed compound for purposes of

pre-AIA

35 U.S.C. 102(b)

C.f.,

In re Ruschig,

343 F.2d 965, 974, 145 USPQ 274, 282 (CCPA

1965) (Rejection of claimed compound in light of prior art genus based on

Petering

is not appropriate where the prior art does

not disclose a small recognizable class of compounds with common

properties.).

(b)

Consider the Express Teachings

If the prior art reference expressly teaches a particular

reason to select the claimed species or subgenus, Office personnel should

point out the express disclosure and explain why it would have been obvious

to one of ordinary skill in the art to select the claimed invention. An

express teaching may be based on a statement in the prior art reference such

as an art recognized equivalence. For example, see

Merck & Co.

v. Biocraft Labs.,

874 F.2d 804, 807, 10 USPQ2d 1843, 1846

(Fed. Cir. 1989) (holding claims directed to diuretic compositions

comprising a specific mixture of amiloride and hydrochlorothiazide were

obvious over a prior art reference expressly teaching that amiloride was a

pyrazinoylguanidine which could be coadministered with potassium excreting

diuretic agents, including hydrochlorothiazide which was a named example, to

produce a diuretic with desirable sodium and potassium eliminating

properties). See also,

In re Kemps,

97 F.3d 1427, 1430,

40 USPQ2d 1309, 1312 (Fed. Cir. 1996) (holding it would have been obvious to

combine teachings of prior art to achieve claimed invention where one

reference specifically refers to the other).

xcreting

diuretic agents, including hydrochlorothiazide which was a named example, to

produce a diuretic with desirable sodium and potassium eliminating

properties). See also,

In re Kemps,

97 F.3d 1427, 1430,

40 USPQ2d 1309, 1312 (Fed. Cir. 1996) (holding it would have been obvious to

combine teachings of prior art to achieve claimed invention where one

reference specifically refers to the other).

(c)

Consider the Teachings of Structural Similarity

Consider any teachings of a “typical,” “preferred,” or

“optimum” species or subgenus within the disclosed genus. If such a prior

art species or subgenus is structurally similar to that claimed, its

disclosure may provide a reason for one of ordinary skill in the art to

choose the claimed species or subgenus from the genus, based on the

reasonable expectation that structurally similar species usually have

similar properties. See, e.g.,

Dillon,

919 F.2d at 693,

696, 16 USPQ2d at 1901, 1904. See also

In re Deuel,

F.3d 1552, 1558, 34 USPQ2d 1210, 1214 (Fed. Cir. 1995) (“Structural

relationships may provide the requisite motivation or suggestion to modify

known compounds to obtain new compounds. For example, a prior art compound

may suggest its homologs because homologs often have similar properties and

therefore chemists of ordinary skill would ordinarily contemplate making

them to try to obtain compounds with improved properties.”).

In making an obviousness determination, Office personnel

should consider the number of variables which must be selected or modified,

and the nature and significance of the differences between the prior art and

the claimed invention. See, e.g.,

In re Jones,

958 F.2d

347, 350, 21 USPQ2d 1941, 1943 (Fed. Cir

ld ordinarily contemplate making

them to try to obtain compounds with improved properties.”).

In making an obviousness determination, Office personnel

should consider the number of variables which must be selected or modified,

and the nature and significance of the differences between the prior art and

the claimed invention. See, e.g.,

In re Jones,

958 F.2d

347, 350, 21 USPQ2d 1941, 1943 (Fed. Cir. 1992) (reversing obviousness

rejection of novel dicamba salt with acyclic structure over broad prior art

genus encompassing claimed salt, where disclosed examples of genus were

dissimilar in structure, lacking an ether linkage or being cyclic);

In re Susi,

440 F.2d 442, 445, 169 USPQ 423, 425 (CCPA

1971) (the difference from the particularly preferred subgenus of the prior

art was a hydroxyl group, a difference conceded by applicant “to be of

little importance”). In the area of biotechnology, an exemplified species

may differ from a claimed species by a conservative substitution (“the

replacement in a protein of one amino acid by another, chemically similar,

amino acid... [which] is generally expected to lead to either no change or

only a small change in the properties of the protein.”

Dictionary

of Biochemistry and Molecular Biology

97 (John Wiley &

Sons, 2d ed. 1989)). The effect of a conservative substitution on protein

function depends on the nature of the substitution and its location in the

chain. Although at some locations a conservative substitution may be benign,

in some proteins only one amino acid is allowed at a given position. For

example, the gain or loss of even one methyl group can destabilize the

structure if close packing is required in the interior of domains. James

Darnell

et al.,

Molecular Cell Biology

51 (W. H. Freeman & Co., 2d

ed. 1990)

ution and its location in the

chain. Although at some locations a conservative substitution may be benign,

in some proteins only one amino acid is allowed at a given position. For

example, the gain or loss of even one methyl group can destabilize the

structure if close packing is required in the interior of domains. James

Darnell

et al.,

Molecular Cell Biology

51 (W. H. Freeman & Co., 2d

ed. 1990).

The closer the physical and/or chemical similarities

between the claimed species or subgenus and any exemplary species or

subgenus disclosed in the prior art, the greater the expectation that the

claimed subject matter will function in an equivalent manner to the genus.

See, e.g.,

Dillon,

919 F.2d at 696, 16 USPQ2d at 1904

(and cases cited therein).

Cf.

Baird,

16 F.3d at 382-83, 29 USPQ2d at 1552 (disclosure

of dissimilar species can provide teaching away).

Similarly, consider any teaching or suggestion in the

reference of a preferred species or subgenus that is significantly different

in structure from the claimed species or subgenus. Such a teaching may weigh

against selecting the claimed species or subgenus and thus against a

determination of obviousness.

Baird,

16 F.3d at 382-83,

29 USPQ2d at 1552 (reversing obviousness rejection of species in view of

large size of genus and disclosed “optimum” species which differed greatly

from and were more complex than the claimed species);

Jones,

958 F.2d at 350, 21 USPQ2d at 1943 (reversing

obviousness rejection of novel dicamba salt with acyclic structure over

broad prior art genus encompassing claimed salt, where disclosed examples of

genus were dissimilar in structure, lacking an ether linkage or being

cyclic). For example, teachings of preferred species of a complex nature

within a disclosed genus may motivate an artisan of ordinary skill to make

similar complex species and thus teach away from making simple species

within the genus.

Baird,

16 F.3d at 382, 29 USPQ2d at

1552

compassing claimed salt, where disclosed examples of

genus were dissimilar in structure, lacking an ether linkage or being

cyclic). For example, teachings of preferred species of a complex nature

within a disclosed genus may motivate an artisan of ordinary skill to make

similar complex species and thus teach away from making simple species

within the genus.

Baird,

16 F.3d at 382, 29 USPQ2d at

1552. See also

Jones,

958 F.2d at 350, 21 USPQ2d at 1943

(disclosed salts of genus held not sufficiently similar in structure to

render claimed species

prima facie

obvious).

Concepts used to analyze the structural similarity of

chemical compounds in other types of chemical cases are equally useful in

analyzing genus-species cases. For example, a claimed tetra-orthoester fuel

composition was held to be obvious in light of a prior art tri-orthoester

fuel composition based on their structural and chemical similarity and

similar use as fuel additives.

Dillon,

919 F.2d at

692-93, 16 USPQ2d at 1900-02. Likewise, claims to amitriptyline used as an

antidepressant were held obvious in light of the structural similarity to

imipramine, a known antidepressant prior art compound, where both compounds

were tricyclic dibenzo compounds and differed structurally only in the

replacement of the unsaturated carbon atom in the center ring of

amitriptyline with a nitrogen atom in imipramine.

In re Merck &

Co.,

800 F.2d 1091, 1096-97, 231 USPQ 375, 378-79 (Fed. Cir.

1986). Other structural similarities have been found to support a

prima facie

case of obviousness. See, e.g.,

In re May,

574 F.2d 1082, 1093-95, 197 USPQ 601,

610-11 (CCPA 1978) (stereoisomers);

In re Wilder,

563

F.2d 457, 460, 195 USPQ 426, 429 (CCPA 1977) (adjacent homologs and

structural isomers);

In re Hoch,

428 F.2d 1341, 1344, 166

USPQ 406, 409 (CCPA 1970) (acid and ethyl ester);

In re

Druey,

319 F.2d 237, 240, 138 USPQ 39, 41 (CCPA 1963) (omission

of methyl group from pyrazole ring)

ess. See, e.g.,

In re May,

574 F.2d 1082, 1093-95, 197 USPQ 601,

610-11 (CCPA 1978) (stereoisomers);

In re Wilder,

563

F.2d 457, 460, 195 USPQ 426, 429 (CCPA 1977) (adjacent homologs and

structural isomers);

In re Hoch,

428 F.2d 1341, 1344, 166

USPQ 406, 409 (CCPA 1970) (acid and ethyl ester);

In re

Druey,

319 F.2d 237, 240, 138 USPQ 39, 41 (CCPA 1963) (omission

of methyl group from pyrazole ring). Generally, some teaching of a

structural similarity will be necessary to suggest selection of the claimed

species or subgenus.

Id.

(d)

Consider the Teachings of Similar Properties or Uses

Consider the properties and utilities of the structurally

similar prior art species or subgenus. It is the properties and utilities

that provide real world motivation for a person of ordinary skill to make

species structurally similar to those in the prior art.

Dillon,

919 F.2d at 697, 16 USPQ2d at 1905;

In re Stemniski,

444 F.2d 581, 586, 170 USPQ 343, 348

(CCPA 1971). Conversely, lack of any known useful properties weighs against

a finding of motivation to make or select a species or subgenus.

re Albrecht,

514 F.2d 1389, 1392, 1395-96, 185 USPQ 585, 587,

590 (CCPA 1975) (The prior art compound so irritated the skin that it could

not be regarded as useful for the disclosed anesthetic purpose, and

therefore a person skilled in the art would not have been motivated to make

related compounds.);

Stemniski,

444 F.2d at 586, 170 USPQ

at 348 (close structural similarity alone is not sufficient to create a

prima facie

case of obviousness when the reference

compounds lack utility, and thus there is no motivation to make related

compounds.). However, the prior art need not disclose a newly discovered

property in order for there to be a

prima facie

case of

obviousness.

Dillon,

919 F.2d at 697, 16 USPQ2d at

1904-05 (and cases cited therein)

close structural similarity alone is not sufficient to create a

prima facie

case of obviousness when the reference

compounds lack utility, and thus there is no motivation to make related

compounds.). However, the prior art need not disclose a newly discovered

property in order for there to be a

prima facie

case of

obviousness.

Dillon,

919 F.2d at 697, 16 USPQ2d at

1904-05 (and cases cited therein). If the claimed invention and the

structurally similar prior art species share any useful property, that

will generally be sufficient to motivate an artisan of ordinary skill to

make the claimed species,

e.g., id.

For example, based on

a finding that a tri-orthoester and a tetra-orthoester behave similarly in

certain chemical reactions, it has been held that one of ordinary skill in

the relevant art would have been motivated to select either structure. 919

F.2d at 692, 16 USPQ2d at 1900-01. In fact, similar properties may normally

be presumed when compounds are very close in structure.

Dillon,

919 F.2d at 693, 696, 16 USPQ2d at 1901, 1904.