United States Court of Appeals for the Federal Circuit 

 2007-1266 

CARNEGIE MELLON UNIVERSITY 

and THREE RIVERS BIOLOGICALS, INC., 

Plaintiffs-Appellants, 

v. 

HOFFMANN-LA ROCHE INC., 

ROCHE MOLECULAR SYSTEMS, INC., 

ROCHE DIAGNOSTIC SYSTEMS, INC., 

ROCHE BIOMEDICAL LABORATORIES, INC., 

THE PERKIN-ELMER CORPORATION, 

and LABORATORY CORPORATION OF AMERICA HOLDINGS, 

Defendants-Appellees. 

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2007-1267 

CARNEGIE MELLON UNIVERSITY, 

Plaintiff-Appellant, 

v. 

HOFFMANN-LA ROCHE INC., 

ROCHE MOLECULAR SYSTEMS, INC., 

ROCHE DIAGNOSTICS CORPORATION, 

LABORATORY CORPORATION OF AMERICA, 

and APPLERA CORPORATION, 

 Defendants-Appellees. 

 Frederick H. Colen, Reed Smith LLP, of Pittsburgh, Pennsylvania, argued for all 

plaintiffs-appellants. With him on the briefs were Charles H. Dougherty, Jr. and Mark 

Levin. 

 Stephen S. Rabinowitz, Fried, Frank, Harris, Shriver & Jacobson LLP, of New 

York, New York, argued for all defendants-appellees. With him on the briefs were 

Mitchell Epner, Randy C. Eisensmith, and Alison R. Ladd. 

Appealed from: United States District Court for the Northern District of California 

Judge Susan Illston 
United States Court of Appeals for the Federal Circuit 

 

2007-1266 

CARNEGIE MELLON UNIVERSITY 

and THREE RIVERS BIOLOGICALS, INC., 

 Plaintiffs-Appellants, 

v. 

HOFFMANN-LA ROCHE INC., 

ROCHE MOLECULAR SYSTEMS, INC., 

ROCHE DIAGNOSTIC SYSTEMS, INC., 

ROCHE BIOMEDICAL LABORATORIES, INC., 

THE PERKIN-ELMER CORPORATION, 

and LABORATORY CORPORATION OF AMERICA HOLDINGS, 

 

Defendants-Appellees. 

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2007-1267 

CARNEGIE MELLON UNIVERSITY, 

 Plaintiff-Appellant, 

v. 

HOFFMANN-LA ROCHE INC., 

ROCHE MOLECULAR SYSTEMS, INC., 

ROCHE DIAGNOSTICS CORPORATION, 

LABORATORY CORPORATION OF AMERICA, 

and APPLERA CORPORATION, 

Defendants-Appellees. 

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Appeal from the United States District Court for the Northern District of 

California in Case Nos. 95-CV-3524 and 01-CV-0415, Judge Susan 

Illston. 
_____________________ 

DECIDED: September 8, 2008 

_____________________ 

Before LOURIE, BRYSON, and PROST, Circuit Judges. 

LOURIE, Circuit Judge. 

 Carnegie Mellon University (“CMU”) and Three Rivers Biologicals, Inc. 

(collectively “appellants”) appeal from the decision of the United States District Court for 

the Northern District of California holding that Hoffmann-La Roche, Inc., Roche 

Molecular Systems, Inc., Roche Diagnostic Systems, Inc., Roche Biomedical 

Laboratories, Inc., The Perkin Elmer Corporation, and Laboratory Corporation of 

America Holdings (collectively “Roche”) do not infringe the patents in suit and that 

certain claims are invalid for lack of written description. Because we conclude that the 

district court did not err in holding the claims invalid for failure to meet the written 

description requirement, we affirm the court’s judgment of invalidity. Because we 

conclude that the court did not err in its infringement analysis, we affirm the court’s 

judgment of noninfringement. 

BACKGROUND 

Proteins, one of the most versatile biomolecules, can serve many important 

roles, including as signal receptors, structural elements, or enzymes. They are encoded 

by particular deoxyribonucleic acid (“DNA”) sequences known as genes. The process 

by which cells use the information contained in genes to make corresponding proteins is 

referred to as expression. Expression involves two steps, viz., transcription and 

translation. During transcription, the information contained in a gene is copied into 

2007-1266, -1267 2
messenger ribonucleic acid (“mRNA”). The cell then assembles amino acids in the 

proper sequence during translation to make the protein based on the information 

contained in the mRNA. 

One gene in the bacterium E. coli, called the E. coli polA gene, encodes a protein 

known as E. coli DNA polymerase I. Since at least the 1970s, the E. coli polA gene has 

been the subject of scientific study. The wild-type E. coli polA gene consists of two 

parts—the structural gene (or gene coding region) and a promoter, which is a DNA 

sequence that is involved in initiating transcription. The expression of a gene can be 

regulated through the use of a promoter by controlling the level of transcription. 

Some valuable proteins are either difficult to purify from their natural sources or 

occur in minute quantities in nature. Thus, methods have been developed in the field of 

biotechnology “to synthesize useful quantities of specific proteins by controlling the 

mechanism by which living cells make proteins.” Carnegie Mellon Univ. v. Hoffmann-La 

Roche, Inc., 55 F. Supp. 2d 1024, 1027 (N.D.Cal. 1999). 

One method involves introducing foreign genes into a bacterium, which can then 

replicate as the bacterium grows and divides. Such a method involves several steps, 

including isolating and cloning the gene that encodes the protein of interest and 

introducing the cloned gene into the host bacterium. The latter is accomplished by 

incorporating the gene into a cloning vector. Certain types of vectors include 

bacteriophages and plasmids, which are “small circular loop[s] of DNA found in bacteria, 

separate from the chromosome, that replicate[] like a chromosome.” Id. Recombinant 

DNA techniques are used to modify plasmids by recombining cloned genes and other 

2007-1266, -1267 3
segments of DNA that contain control sequences. The plasmid is then introduced into 

the host bacterium where it will replicate as the bacterium grows and divides. 

The patents in suit, viz., U.S. Patents 4,767,708 (“the ’708 patent”), 5,126,270 

(“the ’270 patent”), and 6,017,745 (“the ’745 patent”) relate to “novel recombinant 

plasmids for the enhanced expression of an enzyme, to the preparation by gene cloning 

of such plasmids, to bacterial strains containing said plasmids, [and] to methods for the 

conditional control of the expression of said enzyme.”1

 ’708 patent col.1 ll.7-16. 

The patents teach that the enzyme of interest is DNA polymerase I (Pol I), which, 

as discussed above, is encoded by the structural gene known as polA. Id. col.1 ll.14-

15. In the prior art, scientists encountered difficulties cloning polA into multicopy 

plasmids because the increase in expression of DNA polymerase I above the natural 

level of expression was found to be lethal to a host bacterium. Id. col.1 ll.14-18. The 

claimed inventions overcome that problem by constructing a novel plasmid containing 

“the entire and undamaged polA gene coding region enzymatically excised from a DNA 

molecule,” which “contains essentially none of or at the most only a portion of the 

activity of its natural promoter.” Id. col.2 ll.23-29. The patents disclose that severely 

damaging the natural polA promoter sequence constituted a “significant discovery of the 

present invention since it eliminates or greatly reduces the unregulated expression of 

Pol I, which would otherwise be lethal to the cell.” Id. col.2 ll.43-46. By cloning the 

 1

 The patents in suit, which are owned by CMU, all share a common 

specification. The ’708 patent, which was filed by Edwin G. Minkley, Jr. and William E. 

Brown on August 7, 1984, issued from Application No. 07/638, 638 (“the ’638 

application”). The ’270 patent is a continuation of the application that issued as the ’708 

patent, and the ’745 patent is a continuation of the application that issued as the ’270 

patent. Throughout this opinion, we will cite the ’708 patent when referencing the 

common specification. 

2007-1266, -1267 4
gene for DNA polymerase I into a vector along with a foreign promoter whose activity is 

conditionally controlled, one can obtain an amplified amount of DNA polymerase I. 

Throughout the specification, the patents teach that the host bacterial strain that is used 

to achieve that objective is E. coli. 

The patents in suit share a common specification, and the claims are directed to 

recombinant plasmids that contain gene coding regions for the expression of DNA 

polymerase I from any bacterial source. For example, claim 1 of the ’708 patent reads 

as follows: 

1. A recombinant plasmid containing a cloned complete structural gene 

coding region isolated from a bacterial source for the expression of DNA 

polymerase I, under operable control of a conditionally controllable foreign 

promoter functionally linked to said structural gene coding region, said 

foreign promoter being functional to express said DNA polymerase I in a 

suitable bacterial or yeast host system. 

’708 patent claim 1 (emphasis added). Claim 1 of the ’270 patent recites: 

1. A recombinant plasmid providing for Nick-translation activity isolated 

from a bacterial source, said plasmid capable of being placed in a 

bacterial host system such that the host system can grow and divide. 

’270 patent claim 1 (emphasis added). Similarly, claim 1 of the ’745 patent reads: 

1. A recombinant plasmid containing a DNA coding sequence for the 

expression of DNA polymerase activity, wherein said DNA coding 

sequence is derived from a source that encodes a bacterial DNA 

Polymerase, said source not containing an amber mutation affecting 

expression of said DNA polymerase activity, such that when said plasmid 

is transformed into a bacterial host system the host system can grow and 

divide thereby replicating said plasmid. 

’745 claim 1 (emphasis added). 

Roche commercially manufactures recombinant DNA polymerases. The 

accused product at issue in this appeal involves a recombinant plasmid referred to as 

pLSG5, which causes host cells to express an enzyme known as Thermus aquaticus

2007-1266, -1267 5
(“Taq”) DNA polymerase. On August 30, 1994, appellants filed suit against Roche 

asserting that its product, pLSG5, infringes the ’708 and ’270 patents.2 The district 

court held a claim construction hearing on January 14, 1997 and issued its claim 

construction ruling on March 31, 1997. The court construed the term “DNA polymerase” 

as requiring 3’-5’ exonuclease activity. Carnegie Mellon Univ. v. Hoffmann-La Roche 

Inc., No. C 95-3524 SI, 1997 WL 33152823, at *8-*10 (N.D. Cal. Mar. 31, 1997). Roche 

filed separate motions for summary judgment seeking judgment that: 1) claims 1-19, 22-

40, and 43-45 of the ’708 patent were invalid for lack of written description under our 

holding in Regents of University of California v. Eli Lilly & Co., 119 F.3d 1559 (Fed. Cir. 

1997); 2) claims 1-6, 10-19, and 22-40 of the ’708 patent were not infringed; and 3) 

claims 1-2, 11-12, 14-15, 17-18, 20-21, 23-24, 26-27, 29-30, and 32-36 of the ’270 

patent were invalid for lack of written description under our holding in Gentry Gallery, 

Inc. v. Berkline Corp., 134 F.3d 1473 (Fed. Cir. 1998), or, in the alternative, under Eli 

Lilly. 

On May 12, 1999, the district court granted Roche’s motion for summary 

judgment of noninfringement. Carnegie Mellon Univ. v. Hoffmann-La Roche, Inc., 55 F. 

Supp. 2d 1024 (N.D.Cal. 1999). In doing so, the district court concluded that there was 

no genuine issue of material fact as to whether the enzyme in the accused product 

possessed 3’-5’ exonuclease activity. Because the undisputed evidence indicated that 

the accused products lacked that element, the court concluded that summary judgment 

of noninfringement of the ’708 patent was required. 

 2

 In its original complaint, appellants asserted that several of Roche’s 

recombinant DNA plasmids infringe the ’708 and ’270 patents. On appeal, however, 

appellants only challenge the district court’s grant of summary judgment of 

noninfringement with respect to the pLSG5 plasmid. 

2007-1266, -1267 6
On August 19, 1999, the district court granted Roche’s motion for summary 

judgment of invalidity as to the ’270 patent. Carnegie Mellon Univ. v. Hoffmann-La 

Roche Inc., No. C 95-3524 SI, 1999 WL 33298545 (N.D. Cal. Aug. 19, 1999). The 

court determined that the specification of the ’270 patent made clear that lethality was 

an essential feature of the invention and thus, under Gentry Gallery, the claims of the 

patent must contain that feature in order to comply with the written description 

requirement. Because the claims omit the feature of lethality, the court concluded that 

those claims of the ’270 patent were invalid. 

On June 27, 2001, relying on Eli Lilly, the district court granted Roche’s motion 

for summary judgment of invalidity with regard to the ’708 patent. Carnegie Mellon 

Univ. v. Hoffmann-La Roche, Inc., 148 F. Supp. 2d 1004 (N.D. Cal. 2001). The court 

concluded that while the claims of the ’708 patent claim recombinant plasmids 

“containing a cloned complete structural gene coding region from [any] bacterial 

sources for the expression of DNA polymerase I,” the ’638 application only described 

recombinant plasmids containing the encoding gene region for E. coli DNA polymerase I 

and thus failed to adequately support the generic claims of the ’708 patent. 

On January 24, 2001, CMU initiated a second patent infringement action against 

Roche, alleging that Roche infringed the ’745 patent. Roche moved for summary 

judgment that claims 1-3, 12-14, 23-28, and 30-33 were invalid under the written 

description requirement of 35 U.S.C. § 112. On September 29, 2003, the district court 

granted that motion. Carnegie Mellon Univ. v. Hoffmann-La Roche, Inc., No. C 01-0415 

SI (N.D. Cal. Sept. 29, 2003). Again relying on Eli Lilly, the court determined that there 

was no genuine issue of material fact with regard to whether the ’745 patent complies 

2007-1266, -1267 7
with the written description requirement under 35 U.S.C. § 112 and granted Roche’s 

motion. Roche also moved for summary judgment of noninfringement of claims 4-11, 

15-22, and 29 of the ’745 patent under the doctrine of equivalents, and on February 26, 

2004, the court granted that motion. Carnegie Mellon Univ. v. Hoffmann-La Roche, Inc., 

No. C 01-0415 SI (N.D. Cal. Feb. 26, 2004). 

Roche additionally asserted that the patents were unenforceable based on 

inequitable conduct committed by appellants during the prosecution of each of the 

asserted patents. The district court held a bench trial on that issue from August 1 to 

August 5, 2005. On March 22, 2007, the court issued its ruling, holding that Roche 

failed to present clear and convincing evidence that appellants committed inequitable 

conduct. Carnegie Mellon Univ. v. Hoffmann-La Roche, Inc., No. C 01-0415 SI, 2007 

WL 902548 (N.D. Cal. Mar. 22, 2007). As such, the court concluded that none of the 

patents was unenforceable. 

On May 14, 2007, the district court entered final judgment in favor of Roche. 

Appellants timely appealed the district court’s grant of summary judgment with regard to 

noninfringement and invalidity. We have jurisdiction pursuant to 28 U.S.C. § 1295(a)(1). 

DISCUSSION 

On appeal, appellants challenge the district court’s grant of summary judgment of 

invalidity with regard to claims 1-19, 22-40, and 43-45 of the ’708 patent, claims 1-2, 11-

12, 14-15, 17-18, 20-21, 23-24, 26-27, 29-30, and 32-36 of the ’270 patent, and claims 

3, 14, 23-28, and 30-32 of the ’745 patent. In addition, appellants challenge the court’s 

grant of summary judgment of noninfringement of the asserted claims of the ’708 patent 

and claims 4, 5, and 7 of the ’745 patent. While the decisions of the district court 

2007-1266, -1267 8
regarding the ’708, ’270, and ’745 patents were rendered in separate opinions and 

judgments, the appeals were consolidated for argument in this court and we decide all 

of them together. We first consider appellants’ arguments relating to validity. 

A. Standard of Review

We review the district court’s grant of summary judgment de novo, reapplying the 

standard applicable at the district court. See Rodime PLC v. Seagate Tech., Inc., 174 

F.3d 1294, 1301 (Fed. Cir. 1999). Summary judgment is appropriate “if the pleadings, 

depositions, answers to interrogatories, and admissions on file, together with the 

affidavits, if any, show that there is no genuine issue as to any material fact and that the 

moving party is entitled to judgment as a matter of law.” Fed. R. Civ. P. 56(c). In 

addition, in deciding a motion for summary judgment, “[t]he evidence of the nonmovant 

is to be believed, and all justifiable inferences are to be drawn in his favor.” Anderson v. 

Liberty Lobby, Inc., 477 U.S. 242, 255 (1986). 

B. Written Description

Section 112, paragraph 1 of the Patent Act sets forth the written description 

requirement as follows: 

The specification shall contain a written description of the invention, and of 

the manner and process of making and using it, in such full, clear, 

concise, and exact terms as to enable any person skilled in the art to 

which it pertains, or with which it is most nearly connected, to make and 

use the same, and shall set forth the best mode contemplated by the 

inventor of carrying out his invention. 

35 U.S.C. § 112, ¶ 1 (emphasis added). Thus, paragraph 1 of § 112 requires a written 

description of the invention—a requirement separate and distinct from the enablement 

requirement. Vas-Cath Inc. v. Mahurkar, 935 F.2d 1555, 1563 (Fed. Cir. 1991); see

Festo Corp. v. Shoketsu Kinzoku Kogyo Kabushiki Co., Ltd., 535 U.S. 722, 736 (2002) 

2007-1266, -1267 9
(noting that “a number of statutory requirements must be satisfied before a patent can 

issue” including that the patent application “describe, enable, and set forth the best 

mode of carrying out the invention”) (emphasis added); see also In re Curtis, 354 F.3d 

1347, 1357 (Fed. Cir. 2004) (“We interpret 35 U.S.C. § 112, ¶ 1 to require a written 

description requirement separate and apart from the enablement requirement.”); In re 

Ruschig, 379 F.2d 990 (C.C.P.A. 1967) (holding that the written description requirement 

is a requirement separate from enablement under 35 U.S.C. § 112, paragraph 1). 

 The basic function of a patent specification is to disclose an invention. It has 

long been the case that a patentee “can lawfully claim only what he has invented and 

described, and if he claims more his patent is void.” O’Reilly v. Morse, 56 U.S. (15 

How.) 62, 121 (1853). The written description serves a quid pro quo function “in which 

the public is given ‘meaningful disclosure in exchange for being excluded from 

practicing the invention for a limited period of time.’” Univ. of Rochester v. G.D. Searle 

& Co., Inc., 358 F.3d 916, 922 (Fed. Cir. 2004) (quoting Enzo Biochem, Inc. v. GenProbe Inc., 323 F.3d 956, 970 (Fed. Cir. 2002)). To satisfy the written description 

requirement, “the applicant does not have to utilize any particular form of disclosure to 

describe the subject matter claimed, but the description must clearly allow persons of 

ordinary skill in the art to recognize that he or she invented what is claimed.” In re 

Alton, 76 F.3d 1168, 1172 (Fed. Cir. 1996) (citing In re Gosteli, 872 F.2d 1008, 1012 

(Fed. Cir. 1989)) (quotations omitted). In other words, the applicant must “convey with 

reasonable clarity to those skilled in the art that, as of the filing date sought, he or she 

was in possession of the invention,” Vas-Cath Inc., 935 F.2d at 1563-64, and 

demonstrate that by disclosure in the specification of the patent. Whether the written 

2007-1266, -1267 10
description requirement is satisfied is a fact-based inquiry that will depend on the nature 

of the claimed invention, Enzo, 323 F.3d at 963, and the knowledge of one skilled in the 

art at the time an invention is made and a patent application is filed. Such knowledge 

may change as time progresses. See In re Wallach, 378 F.3d 1330, 1334 (Fed. Cir. 

2004) (discussing how it is now a “routine matter” to convert between an amino acid 

sequence and the DNA sequences that can encode it such that an applicant need not 

specify each possible permutation of nucleic acid sequences for a particular protein). 

 Our case law has examined compliance with the written description requirement 

in the context of biotechnological inventions in the past. In Regents of University of 

California v. Eli Lilly & Co., 119 F.3d 1559 (Fed. Cir. 1997), we held, inter alia, that 

generic claims directed to recombinant prokaryotic microorganisms comprising any 

vertebrate and mammalian cDNA were not adequately supported by the specification 

that only disclosed rat insulin cDNA. Id. at 1568. We stated that “[a]n adequate written 

description of a DNA, such as the cDNA of the recombinant plasmids and 

microorganisms of the claimed invention, requires a precise definition, such as by 

structure, formula, chemical name, or physical properties, not a mere wish or plan for 

obtaining the claimed chemical invention.” Id. at 1566 (internal quotations omitted). We 

further held that “[a] description of a genus of cDNAs may be achieved by means of a 

recitation of a representative number of cDNAs, defined by nucleotide sequence, falling 

within the scope of the genus or of a recitation of structural features common to the 

members of the genus, which features constitute a substantial portion of the genus.” Id.

at 1569. 

1. The ’708 and ’745 Patents 

2007-1266, -1267 11
 Appellants challenge the district court’s conclusion that certain claims of the ’708 

and ’745 patents are invalid under § 112 in light of our holding in Eli Lilly. According to 

appellants, Eli Lilly is distinguishable from the present case because the invention in Eli 

Lilly was tied to a specific cDNA sequence, whereas the invention here involves a 

combination of well known elements that create a generic biotechnological tool. 

Appellants further argue that the court erred by failing to conduct a factual inquiry as 

required by Capon v. Eshhar, 418 F.3d 1349, 1358 (Fed. Cir. 2005). Appellants 

contend that at the time of the invention, both DNA polymerase I and the polA gene 

were well known in the art. In addition, appellants assert that the court improperly made 

factual determinations, improperly relied on the declaration of Roche’s expert while 

dismissing the declarations of its own experts, and failed to draw inferences in 

appellants’ favor. 

 In response, Roche argues that the district court correctly determined that the 

claims of the ’708 patent encompass more than the subject matter described in the 

specification and thus correctly found them invalid. Roche asserts that Eli Lilly applies 

to the present case as there was nothing in the Eli Lilly decision to suggest that that 

holding was limited to inventions involving novel DNA sequences. Roche further 

asserts that the court considered appellants’ evidence and correctly concluded that they 

failed to raise a genuine issue of material fact. 

We agree with Roche that there is no genuine issue of material fact regarding 

whether the written descriptions of the ’708 and ’745 patents fail to adequately describe 

the claimed invention. We first consider the claims at issue. Claim 1 of the ’708 patent, 

a representative claim, recites: 

2007-1266, -1267 12
1. A recombinant plasmid containing a cloned complete structural gene 

coding region isolated from a bacterial source for the expression of DNA 

polymerase I, under operable control of a conditionally controllable foreign 

promoter functionally linked to said structural gene coding region, said 

foreign promoter being functional to express said DNA polymerase I in a 

suitable bacterial or yeast host system. 

’708 patent claim 1 (emphases added). Similarly, claims 1-3, and 23 of the ’745 patent, 

also representative claims, read as follows: 

1. A recombinant plasmid containing a DNA coding sequence for the 

expression of DNA polymerase activity, wherein said DNA coding 

sequence is derived from a source that encodes a bacterial DNA 

Polymerase, said source not containing an amber mutation affecting 

expression of said DNA polymerase activity, such that when said plasmid 

is transformed into a bacterial host system the host system can grow and 

divide thereby replicating said plasmid. 

2. The recombinant plasmid of claim 1 wherein said DNA polymerase 

activity includes Nick-translation activity. 

3. The plasmid of claim 2 wherein said Nick-translation activity is under 

operable control of a conditionally controllable foreign promoter, said 

foreign promoter being functional to express said Nick-translation activity 

in said host system. 

23. A method of producing an enzyme possessing DNA polymerase 

activity comprising the steps of: 

transforming a recombinant plasmid having a DNA coding sequence for 

the expression of DNA polymerase activity that is under operable control 

of a conditionally controllable foreign promoter into a bacterial host 

system, said DNA polymerase coding sequence derived from a source 

that encodes a bacterial DNA polymerase, said source not containing an 

amber mutation affecting expression of said, DNA polymerase activity; 

and 

allowing the host system to grow and divide for at least twenty generations 

thereby replicating said plasmid. 

’745 claim 1-3, 23 (emphases added). 

The appealed claims of the ’708 patent are directed to recombinant plasmids that 

contain a DNA coding sequence that is broadly defined, and only by its function, viz., 

2007-1266, -1267 13
encoding DNA polymerase I. Moreover, the generic claims are not limited to a single 

bacterial species, but broadly encompass coding sequences originating from any

bacterial species. Similarly, the appealed claims of the ’745 patent are broadly directed 

to recombinant plasmids that contain a DNA coding sequence, again, only defined by 

function, viz., encoding an enzyme with either DNA polymerase or nick-translation 

activity. Those claims are also not limited to a single bacterial species, but cover all 

bacterial species. 

As a preliminary matter, we reject appellants’ assertion that this case is 

distinguishable from Eli Lilly. Contrary to appellants’ assertion, nothing in Eli Lilly

indicates that that holding was limited to inventions involving novel DNA sequences. 

Indeed, in University of Rochester, we rejected a similar argument. See Rochester, 358 

F.3d at 925. 

In Eli Lilly, we held that “the claimed genera of vertebrate and mammal cDNA 

[were] not described by the general language of [a] patent’s written description 

supported only by the specific nucleotide sequence of rat insulin.” 119 F.3d at 1569. 

That holding was premised on the basic principle that a person of skill in the art must be 

able to “visualize or recognize the identity of the members of the genus.” Id. Thus, to 

satisfy the written description requirement for a claimed genus, a specification must 

describe the claimed invention in such a way that a person of skill in the art would 

understand that the genus that is being claimed has been invented, not just a species of 

the genus. 

The Guidelines for Examination of Patent Applications under the 35 U.S.C. 

§ 112, ¶ 1, “Written Description” Requirement, 66 Fed. Reg. 10-99 (Jan. 5, 2001) 

2007-1266, -1267 14
(“Guidelines”), which we find to be an accurate description of the law by the agency 

responsible for examining patent applications, and thus persuasive authority, provide 

further guidance for determining whether the written description requirement is met for 

claims drawn to a genus. The Guidelines state: 

The written description requirement for a claimed genus may be satisfied 

through sufficient description of a representative number of species . . . by 

disclosure of relevant, identifying characteristics, i.e., structure or other 

physical and/or chemical properties, by functional characteristics coupled 

with a known or disclosed correlation between function and structure, or 

by a combination of such identifying characteristics, sufficient to show the 

applicant was in possession of the claimed genus. 

A “representative number of species” means that the species which are 

adequately described are representative of the entire genus. Thus, when 

there is substantial variation within the genus, one must describe a 

sufficient variety of species to reflect the variation within the genus. 

* * * 

Satisfactory disclosure of a “representative number” depends on whether 

one of skill in the art would recognize that the applicant was in possession 

of the necessary common attributes or features of the elements 

possessed by the members of the genus in view of the species disclosed. 

For inventions in an unpredictable art, adequate written description of a 

genus which embraces widely variant species cannot be achieved by 

disclosing only one species within the genus. 

Guidelines, 66 Fed. Reg. at 1106 (emphases added). 

Here, while the claims of the ’708 and ’745 patents encompass a genus of 

recombinant plasmids that contain coding sequences for DNA polymerase or nicktranslation activity from any bacterial source, in contrast, the narrow specifications of the 

’708 and ’745 patents only disclose the polA gene coding sequence from one bacterial 

source, viz., E. coli. Significantly, the specification fails to disclose or describe the polA

gene coding sequence for any other bacterial species. 

2007-1266, -1267 15
The district court concluded that the disclosure of the E. coli polA gene was not 

representative of and failed to adequately support the entire claimed genus. Based on 

the record evidence indicating a lack of a genuine issue of material fact on the issue, we 

agree. Notably, the record indicates that at the time of the invention, only three 

bacterial polA genes, viz., E. coli, K. aerogenes, and K. pneumoniae, out of thousands 

of bacterial species had been cloned, and only E. coli was described in the patents. 

According to Roche’s expert, Dr. Bambara, bacteria constitute a large class of 

organisms that include thousands, and potentially millions, of unidentified species. In 

addition, at the time of the invention, persons of ordinary skill in the art knew that DNA 

polymerase I was not a single enzyme, but a family of enzymes encoded by a family of 

genes that varied from one bacterial species to another. Dr. Bambara stated that those 

enzymes were encoded by genes that were distinct from the E. coli polA gene. 

Significantly, the written descriptions of the ’708 and ’745 patents clearly indicate 

that the polA gene is critical to the claimed invention. Indeed, the patents disclose that 

a “significant discovery of the present invention” involved the need to severely damage 

the polA promoter sequence when constructing the recombinant plasmid in order to 

avoid the unregulated expression of DNA polymerase I, which otherwise would be lethal 

to the cell. ’708 patent col.2 ll.40-46. The specifications disclose that “[t]he novel 

plasmid of the present invention contains the entire and undamaged polA gene coding 

region enzymatically excised from a DNA molecule” and emphasize that “it is an 

important feature of this invention that the cloned polA gene fragment contains 

essentially none of or at the most only a portion of the activity of its natural promoter.” 

Id. col.2 ll.23-29. 

2007-1266, -1267 16
However, although the written descriptions of the patents emphasize that the 

recombinant plasmids must be carefully constructed in order to overcome the lethality 

problem, particularly with regard to the promoter, the patents fail to disclose the 

nucleotide sequence or other descriptive features for a polA gene (including the 

promoter sequence) from any bacterial source other than E. coli. Indeed, in the 

Description of the Preferred Embodiments, the patents disclose only one embodiment 

which uses the plasmid referred to as pMP5. The patents teach that pMP5 was 

constructed by taking the E. coli polA gene from phage NM825, cutting the polA gene 

specifically at the BglII restriction site, and splicing the polA gene into a plasmid 

pHUB2.3 Id. col.5 ll.49-65, Fig. 1. The specification teaches that cutting the polA gene 

at the BglII restriction site was a significant discovery: 

We have discovered that the restriction enzyme BglII will cut within the 

polA promoter sequence and severely damage it. This is a significant 

discovery of the present invention, since it eliminates or greatly reduces 

the unregulated expression of Pol I, which would otherwise be lethal to the 

cell. 

Id. col.2 ll.40-46. As such, the patents teach that the specific gene sequence for the 

expression of DNA polymerase I or nick-translation activity is a critical aspect of the 

invention. 

 We agree with the district court that the narrow disclosure of the E. coli polA

gene is not representative of and fails to adequately support the entire claimed genus 

under Eli Lilly. To satisfy the written description requirement in the case of a chemical 

or biotechnological genus, more than a statement of the genus is normally required. 

 3

 The pMP5 plasmid was transformed into E. coli strain N4830, which resulted 

in strain ATL100. The written description of the patent discloses that ATL100 was 

deposited in the American Type Culture Collection Depository on June 29, 1984, under 

Accession number 39753. ’708 patent col.1 ll.36-41. 

2007-1266, -1267 17
One must show that one has possession, as described in the application, of sufficient 

species to show that he or she invented and disclosed the totality of the genus. In light 

of the specifications’ disclosure concerning the careful construction of the claimed 

recombinant plasmids, such that the natural promoter of the polA gene is severely 

damaged or eliminated, and given the record evidence that the polA gene varied among 

the numerous bacterial species, as well as the absence of any polA gene sequence for 

any bacteria other than E. coli, we conclude that that requirement was not met here. 

We are unpersuaded by appellants’ assertion that a different result is warranted 

in light of our holding in Capon v. Eshhar, 418 F.3d 1349, 1358 (Fed. Cir. 2005). The 

inventions in Capon involved “chimeric DNA that encodes single-chain chimeric proteins 

for expression on the surface of cells of the immune system, plus expression vectors 

and cells transformed by the chimeric DNA.” Id. at 1352. We held that the Board of 

Patent Appeals and Interferences erred in holding that the written description 

requirement was not met because the disclosures failed to “reiterate the structure or 

formula or chemical name for the nucleotide sequences of the claimed chimeric genes.” 

Id. at 1358. We explained that our holding in Eli Lilly did not impose “a per se rule 

requiring recitation in the specification of the nucleotide sequence of claimed DNA, 

when that sequence is already known in the field.” Id. at 1360-61. Moreover, we stated 

that “what is needed to support generic claims to biological subject matter depends on a 

variety of factors, such as the existing knowledge in the particular field, the extent and 

content of the prior art, the maturity of the science or technology, the predictability of the 

aspect at issue, and other considerations appropriate to the subject matter.” Id. 

2007-1266, -1267 18
Unlike the situation in Capon, however, where the prior art contained “extensive 

knowledge of the nucleotide structure of the various immune-related segments of DNA,” 

including “over 785 mouse antibody DNA light chains and 1,327 mouse antibody DNA 

heavy chains,” id. at 1355, the record here shows that only three bacterial polA genes 

out of thousands of genes had been cloned. As such, Capon does not aid appellants. 

Moreover, we disagree with appellants’ assertion that the court failed to properly 

consider the Capon factors in its analysis. The court clearly considered the record 

evidence and properly determined the knowledge of one skilled in the field with respect 

to bacterial polA genes. 

We are further unpersuaded by appellants’ argument that the district court erred 

by failing to consider the declarations of their experts, which, according to appellants, 

create genuine issues of material fact. Appellants primarily point to the declarations of 

Drs. Benkovic, Low, Hatfull, and Davis. Having reviewed that evidence, we agree with 

the district court that they fail to create genuine issues of material fact. Appellants’ 

experts did not dispute the statements made by Dr. Bambara that were material to the 

court’s invalidity holding under Eli Lilly. Indeed, it was undisputed that by 1984, only 

three bacterial polA genes had been cloned. Moreover, Dr. Davis agreed with Dr. 

Bambara’s statement that the polA gene “has different sequences for probably all the 

different bacterial species.” Carnegie Mellon Univ. v. Hoffmann-La Roche, Inc., No. C 

01-0415 SI, slip op. at 10 (N.D. Cal. Sept. 29, 2003). In addition, Dr. Benkovic agreed 

with Dr. Bambara’s assertion that the ’745 patent did not describe polA genes other 

than E. coli. Id. at 11. The additional expert statements relied upon by appellants, 

including statements concerning cloning techniques for purifying polA genes and 

2007-1266, -1267 19
experiments involving E. coli, were immaterial to the relevant inquiry and thus do not 

raise genuine issues of material fact. 

We have considered all of the remaining arguments appellants have raised in 

their briefs and found none that justify a reversal. Accordingly, because no genuine 

issues of material fact exist with regard to whether the written descriptions of the ’708 

and ’745 patents adequately support the appealed claims, we affirm the district court’s 

grant of summary judgment of invalidity with respect to those claims. 

2. The ’270 Patent

 Appellants argue that the district court erred in concluding that the claims of the 

’270 patent are invalid under our holding in Gentry Gallery. According to appellants, the 

court improperly invalidated the claims for lack of written description after concluding 

that they do not recite the problem the invention was intended to solve. Because 

lethality was the key problem solved by the claimed invention, appellants argue that it 

cannot be an “element” of the invention. In response, Roche argues that the court 

correctly concluded that the claims are invalid under Gentry Gallery because they were 

broadened during prosecution to encompass more than the subject matter described in 

the application. In the alternative, Roche asserts that even if the court erred in its 

analysis under Gentry Gallery, the claims are still invalid under Eli Lilly. 

We agree with appellants that the district court erroneously found the claims 

invalid under Gentry Gallery. In reaching its decision, the court found clear and 

convincing evidence that “lethality was an essential feature of the invention claimed in 

the ’270 patent.” Carnegie Mellon, 1999 WL 3329545 at *7. The court concluded that 

2007-1266, -1267 20
under Gentry Gallery, the claims were invalid because the appealed claims did not 

contain that feature. In essence, the court applied an essential element test. 

As we said in Cooper Cameron Corp. v. Kvaerner Oilfield Products, Inc., 291 

F.3d 1317 (Fed. Cir. 2002), in Gentry Gallery “we did not announce a new ‘essential 

element’ test mandating an inquiry into what an inventor considers to be essential to his 

invention and requiring that the claims incorporate those elements.” Id. at 1323. 

Rather, “we applied and merely expounded upon the unremarkable proposition that a 

broad claim is invalid when the entirety of the specification clearly indicates that the 

invention is of a much narrower scope.” Id. We thus agree with appellants that the 

district court erred by invalidating the claims of the ’270 patent by applying the essential 

element test. We further note that even if such a test existed, lethality was only a 

reason for the claimed invention, and not an element of it that needed to be defined in 

the claims. 

However, while the court erred in holding the claims of the ’270 patent invalid 

under Gentry Gallery, we agree with Roche that the claims are nonetheless invalid 

under Eli Lilly under the same rationale discussed above. The claims of the ’270 patent 

suffer the same defects as the appealed claims of the ’708 and ’745 patents. Indeed, 

the claims of the ’270 patent are also generically directed to plasmids encompassing the 

polA gene from any bacterial source. Thus, for the reasons set forth above, we 

conclude that there is no genuine issue of material fact as to whether the claims of the 

’270 patent are invalid for lack of written description under Eli Lilly. 

Accordingly, because the specifications of the ’708, ’745, and ’270 patents fail to 

provide adequate written description support for the appealed claims, all of which 

2007-1266, -1267 21
encompass a genus of recombinant plasmids containing gene coding sequences from 

any bacterial source, we affirm the district court’s grant of summary judgment of 

invalidity. 

B. Noninfringement

 In view of our affirmance of the district court’s invalidity decision, the issue of 

infringement with respect to the asserted claims of the ’708 patent has become moot 

and will not be considered. We will, however, consider appellant’s argument with regard 

to the district court’s grant of summary judgment of noninfringement of claims 4, 5, and 

7 of the ’745 patent, as the validity of those claims has not been challenged and thus 

presumptively they remain valid. 

 Claims 4, 5, and 7 of the ’745 patent are all dependent claims and they 

incorporate the claim limitations of claim 1. Those claims, however, are narrower in 

scope as they require E. coli as the bacterial source. Those claims read as follows: 

1. A recombinant plasmid containing a DNA coding sequence for the 

expression of DNA polymerase activity, wherein said DNA coding 

sequence is derived from a source that encodes a bacterial DNA 

Polymerase, said source not containing an amber mutation affecting 

expression of said DNA polymerase activity, such that when said plasmid 

is transformed into a bacterial host system the host system can grow and 

divide thereby replicating said plasmid. 

4. The recombinant plasmid of claim 3 wherein the bacterial host system 

and the bacterial source are each E. coli; and wherein the Nick-translation 

activity includes polymerase and 5'-3' exonuclease activities. 

5. The recombinant plasmid of claim 4 wherein said foreign promoter is a 

negatively regulated promoter. 

7. The recombinant plasmid of claim 5 wherein said negatively regulated 

promoter is the leftward promoter of phage lambda. 

’745 patent claims 1, 4, 5, & 7 (emphases added). 

2007-1266, -1267 22
 On appeal, appellants argue that the district court erred in concluding that the 

Roche’s pLSG5 product does not infringe the ’745 patent under the doctrine of 

equivalents. According to appellants, the substitution of Taq for E. coli was an 

insubstantial and unimportant change that resulted in an infringing equivalent. Roche 

responds that the court correctly granted summary judgment of noninfringement 

because appellants’ infringement theory would vitiate the E. coli claim limitation of the 

appealed claims, which is impermissible under Warner-Jenkinson Co. v. Hilton Davis 

Chemical Co., 520 U.S. 17 (1997). In addition, Roche contends that, contrary to 

appellants’ assertion, the differences between Taq and E. coli are not insubstantial. 

 We agree with Roche that the district court properly granted summary judgment 

of noninfringement under the doctrine of equivalents. Under that doctrine, “a product or 

process that does not literally infringe upon the express terms of a patent claim may 

nonetheless be found to infringe if there is ‘equivalence’ between the elements of the 

accused product or process and the claimed elements of the patented invention.” Id. at 

21 (citation omitted). However, the “all limitations rule” restricts the doctrine of 

equivalents by preventing its application when doing so would vitiate a claim limitation. 

Id. at 29 (stating that the doctrine of equivalents cannot be applied broadly so as to 

“effectively eliminate that [claim] element in its entirety”). In determining whether a 

finding of infringement under the doctrine of equivalents would vitiate a claim limitation, 

we must consider “the totality of the circumstances of each case and determine whether 

the alleged equivalent can be fairly characterized as an insubstantial change from the 

claimed subject matter without rendering the pertinent limitation meaningless.” 

Freedman Seating Co. v. Am. Seating Co., 420 F.3d 1350, 1359 (Fed. Cir. 2005). 

2007-1266, -1267 23
2007-1266, -1267 24

 We agree with Roche and the district court that a finding that Taq is an 

equivalent of E. coli would essentially render the “bacterial source [is] E. coli” claim 

limitation meaningless, and would thus vitiate that limitation of the claims. Indeed, in 

drafting the claims, the patentees specifically chose to limit claim 4 to a recombinant 

plasmid where the bacterial source is E. coli. Appellants cannot now argue that any 

bacterial source, including Taq, would infringe that claim. Accordingly, summary 

judgment of noninfringement was appropriate.4

 

CONCLUSION 

For the foregoing reasons, we affirm the district court’s grant of summary 

judgment of invalidity with regard to claims 1-19, 22-40, and 43-45 of the ’708 patent, 

claims 1-2, 11-12, 14-15, 17-18, 20-21, 23-24, 26-27, 29-30, and 32-36 of the ’270 

patent, and claims 3, 14, 23-28, and 30-32 of the ’745 patent. In addition, we affirm the 

court’s grant of summary judgment of noninfringement with respect to claims 4, 5, and 7 

of the ’745 patent. 

AFFIRMED

 4

 We note, as Roche states in its briefs, that Taq DNA polymerase was and 

continues to be integral to the success of polymerase chain reaction (“PCR”), a widely 

used technique in molecular biology that was invented by Kary Mullis in 1983. Indeed, 

in 1993, Mullis won the Nobel Prize in Chemistry for his development of PCR and the 

journal Science named Taq DNA polymerase the “Molecule of the Year.” While we 

reach our decision irrespective of those facts, we readily can see why appellants have 

attempted to broaden the scope of their claims beyond the E. coli species disclosed.