Greenliant Systems, Inc. v. Xicor LLC

United States Court of Appeals

for the Federal Circuit

__________________________

GREENLIANT SYSTEMS, INC.,

Plaintiff-Appellee,

and

SILICON STORAGE TECHNOLOGY, INC.,

Plaintiff-Appellee,

v.

XICOR LLC,

Defendant-Appellant.

__________________________

2011-1514

__________________________

Appeal from the United States District Court for the

Northern District of California in case no. 11-CV-0631,

Judge Edward M. Chen.

__________________________

Decided: August 22, 2012

___________________________

JO DALE CAROTHERS, Covington & Burling LLP, of

San Diego, California, argued for all plaintiffs-appellees.

With him on the brief were ALAN H. BLANKENHEIMER,

CHRISTOPHER J. LONGMAN and LESLI RAWLES GALLAGHER.

Of counsel was IAN J. MILLER. Of counsel on the brief

were RONALD L. YIN, MICHAEL G. SCHWARTZ and ERIK R.

GREENLIANT SYSTEMS v. XICOR 2

FUEHRER, DLA Piper LLP, of East Palo Alto, California,

for plaintiff-appellee Greenliant Systems, Inc.

JEFFREY R. BRAGALONE, Shore Chan Braglone

DePumpo LLP, of Dallas, Texas, argued for defendant-

appellant. With him on the brief were MICHAEL W. SHORE

and CHRISTOPHER L. EVANS.

__________________________

Before LINN, PLAGER, and DYK, Circuit Judges.

DYK, Circuit Judge.

Xicor LLC appeals a final judgment of the United

States District Court for the Northern District of Califor-

nia granting a declaratory judgment in favor of Greenli-

ant Systems, Inc. The district court entered the final

judgment pursuant to the parties’ agreement that the

summary judgment order in Silicon Storage Technology,

Inc. v. Xicor LLC (“SST”), 776 F. Supp. 2d 1072 (N.D. Cal.

2011), which held that claims 12 and 13 of reissued U.S.

Patent No. RE38,370 (“the RE’370 patent”) were invalid

under the rule against recapture, “applies equally in this

case and should be entered herein.” See Greenliant Sys-

tems, Inc. v. Xicor LLC, No. 11-CV-0631, slip op. at 3

(N.D. Cal. Jun. 22, 2011). The remaining claims were

dismissed by agreement of the parties. We affirm.

BACKGROUND

Under 35 U.S.C. § 251, a patentee may, within two

years of the issuance of a patent, seek a broadening

reissue of that patent if, among other things, the patentee

originally claimed “less than he had a right to claim.” See

MBO Labs., Inc. v. Becton, Dickinson & Co., 602 F.3d

1306, 1313 (Fed. Cir. 2010). However, under the rule

against recapture, “a patentee is precluded from regaining

the subject matter that he surrendered in an effort to

3 GREENLIANT SYSTEMS v. XICOR

obtain allowance of the original claims.” N. Am. Con-

tainer, Inc. v. Plastipak Packaging, Inc., 415 F.3d 1335,

1349 (Fed. Cir. 2005) (internal quotation marks omitted).

This case presents the question of whether broadening

claims 12 and 13 of the reissued RE’370 patent (the

claims at issue in this case) improperly recaptured claim

scope that Xicor 1 had previously surrendered during the

prosecution of its predecessor, U.S. Patent No. 5,977,585

(“the ’585 patent”).

I

The specifications of the ’585 patent and the RE’370

patent are substantially identical and disclose improve-

ments to electronic memory devices, specifically EEPROM

circuits, in which “the presence or absence of charge on a

floating gate electrode indicates a binary one or zero.”

RE’370 patent col. 1 ll. 20-22; ’585 patent col. 1 ll. 16-18.

In an EEPROM, charge is transferred to and from the

floating gate electrode through a tunneling oxide layer

that acts as an insulator when not actively tunneling.

However, traditional tunneling oxide layers formed by

thermal oxide growth are susceptible to pin-hole defects

as well as compressive stress. The improved tunneling

oxide layer disclosed in the patents reduces defects and

stress, and thereby improves, among other things, proc-

essing yields, reliability, and the useful life of EEPROM

memory.

Claim 1 of the ’585 patent recited:

1. An improved tunneling region for use with an

integrated circuit comprising:

1 The RE’370 was originally assigned to Xicor Corp.,

the predecessor of the current owner, Xicor LLC. For

simplicity, we will refer to these entities collectively as

“Xicor.”

GREENLIANT SYSTEMS v. XICOR 4

a first layer of polysilicon;

a first electron tunneling layer of thermal ox-

ide formed over said first layer of polysilicon;

a second electron tunneling layer of annealed

deposited silicon dioxide formed over said first

tunneling layer having a thickness less than

2000 Angstroms thick, said silicon dioxide

layer being formed by low pressure chemical

vapor deposition comprising the use of tetra-

ethylorthosilicate; and

a second layer of polysilicon formed over said

layer of deposited silicon dioxide, such that

when a bias voltage is applied between said

first layer of polysilicon and said second layer

of polysilicon, electron tunneling will occur

from said first layer of polysilicon to said sec-

ond layer of polysilicon through said first and

second electron tunneling layers.

’585 patent col. 4 l. 66-col. 5 l. 17 (emphasis added).

Claim 4, the only other independent claim of the ’585

patent, recited:

4. A semiconductor device including means for

electron tunneling, comprising:

a first conductive layer;

an annealed silicon dioxide tunneling layer

having a thickness less than 2000 Angstroms

formed on top of said conductive layer, said

silicon dioxide layer being formed by low pres-

sure chemical vapor deposition comprising the

use of tetraethylorthosilicate;

a second conductive layer formed on top of

said silicon dioxide layer, said first conductive

5 GREENLIANT SYSTEMS v. XICOR

layer acting as a source of tunneling electrons

under an appropriate voltage bias condition,

said second conductive layer serving as the re-

ceptor of said tunneling electrons.

’585 patent col. 5 l. 25-col. 6 l. 8 (emphasis added). For

the purposes of this case, the two key limits of the dis-

puted “tunneling layer” in both claim 1 and claim 4 of the

’585 patent are that (1) the layer is “formed by low pres-

sure chemical vapor deposition,” and (2) the deposition

“compris[es] the use of tetraethylorthosilicate,” which is

also referred to as “TEOS.” Both of these claims are

product-by-process claims, i.e., the product is defined in

part by the process by which it is made.

II

The ’585 patent and the RE’370 patent relate back to

U.S. Patent Application No. 07/195,766 (“the ’766 applica-

tion”), filed on May 17, 1988. Claims 1-12 of the originally

filed ’766 application covered methods for depositing an

electron tunneling layer, while claim 13 covered a device

containing such a deposited tunneling layer. On January

19, 1989, the examiner issued a restriction requirement

under 35 U.S.C. § 121 that required Xicor to separately

prosecute the method claims and the device claim. Xicor

elected to first prosecute the method claims after the

restriction requirement became final on August 3, 1989.

During prosecution of the method claims, the exam-

iner rejected, among others, claim 7 as being obvious in

view of prior art “disclos[ing] that the tunneling oxide

layer can be . . . deposited by [low pressure chemical

vapor deposition].” J.A. 453. However, the examiner

stated that “[i]f claim 7 was amended to recite that the

tunneling oxide layer was deposited by [low pressure

chemical vapor deposition] using TEOS, the claim would

be allowable.” J.A. 454 (emphasis added). Xicor added

GREENLIANT SYSTEMS v. XICOR 6

the TEOS limit, and claim 7 was subsequently allowed as

part of U.S. Patent No. 5,219,774 (“the ’774 patent”),

which issued on June 15, 1993.

On May 18, 1993, while the application for the ’774

patent was still pending, Xicor filed a divisional applica-

tion, which copied independent claim 13, the lone device

claim from the original ’766 application, and added,

among others, independent device claim 14. Claims 13

and 14 of the divisional application eventually issued as

claims 1 and 4 of the ’585 patent, and are thus critical to

the recapture rule issue presented in this case.

On July 28, 1993, the examiner rejected claims 13 and

14, among others, as obvious. In response, Xicor amended

claim 13 to include the “said silicon dioxide layer being

formed by low pressure chemical vapor deposition com-

prising the use of [TEOS]” limit that was already included

in claim 14 as initially drafted in the divisional applica-

tion. J.A. 610.

On March 25, 1994, the examiner again rejected

claims 13 and 14 on anticipation and obviousness

grounds. As described below, the process limitations in

product-by-process claims such as claims 13 and 14 can-

not be used to distinguish prior art unless the process

imparts structural differences to the product. The exam-

iner explained that the process limitations of the device

claims (i.e., how the tunneling layer is “formed by a low

pressure chemical vapor deposition comprising the use of

[TEOS]”) would not be given “patentable weight over . . .

the prior art of record” unless Xicor established that those

process limits imparted “structural limitations” that

distinguished the claimed device from prior art devices.

J.A. 621-23. As described in greater detail below, Xicor

argued in response that “deposited TEOS oxide” did in

fact have “significant structural benefits over prior art

7 GREENLIANT SYSTEMS v. XICOR

thermal oxide layers when used as tunneling layers.” J.A.

632 (first emphasis added). Unpersuaded, the examiner

maintained the rejections. However, the Board of Patent

Appeals and Interferences (“Board”) reversed the exam-

iner’s rejections, finding that the “advantages of TEOS

deposited oxides versus thermally grown oxides” were

“sufficient to establish unobvious differences between” the

claims and the prior art. J.A. 731-32 (emphasis added).

The ’585 patent issued on November 2, 1999, with claims

13 and 14 of the divisional application issuing as claims 1

and 4 of the ’585 patent.

On November 2, 2001, Xicor filed a reissue application

for the ’585 patent. Xicor added new claims 12 and 13,

which omitted the “comprising the use of [TEOS]” limit,

but otherwise duplicated claims 1 and 4 of the ’585 pat-

ent. The reissue examiner found that claims 12 and 13

did not include and were “not broader than the surren-

dered subject matter,” and thus were “not barred by the

recapture rule.” J.A. 2287. The RE’370 patent issued

with new claims 12 and 13 on December 30, 2003.

III

On February 11, 2011, Greenliant filed an action

against Xicor, seeking a declaration that it did not in-

fringe any claims of the RE’370 patent and that all claims

of the RE’370 patent are invalid. The parties agreed that

a summary judgment order in SST, 776 F. Supp. 2d at

1086, determining that claims 12 and 13 of the RE’370

were invalid under the recapture rule, “applies equally in

this case and should be entered herein.” See Greenliant,

No. 11-CV-0631, slip op. at 2-3. Based on the prosecution

history of the ’585 patent, the district court in the SST

case had reasoned that

[a] reasonable, objective observer would conclude

that the TEOS limitation was included in order to

GREENLIANT SYSTEMS v. XICOR 8

distinguish the claimed . . . process limitations [in

the product-by-process claims] from the prior art.

By including the TEOS limitation, Xicor surren-

dered alternative chemicals to TEOS, and these

alternatives were recaptured by claims 12 and 13

of the ’370 reissue patent.

SST, 776 F. Supp. 2d at 1086. 2

Along with the stipulation regarding claims 12 and

13, the parties agreed that Greenliant’s “claims for de-

claratory judgment relief of noninfringement and invalid-

ity that relate to claims 1-11 of the [RE]’370 patent”

should be dismissed based on a covenant not to sue. With

no issues remaining, the district court entered a final

judgment in favor of Greenliant on June 22, 2011, holding

claims 12 and 13 invalid and dismissing the request for

declaratory relief as to claims 1-11. At that time, the

district court also granted SST’s motion to intervene in

the Greenliant case, allowing SST to participate in an

anticipated appeal to this court. On August 1, 2011, the

district court granted Xicor’s motion to clarify the record.

The district court clarified that its judgment was “based

on the legal and factual findings contained in the . . .

March 21, 2011 [SST order],” and ordered that “the

materials on which the [SST order] [wa]s based,” includ-

ing the prosecution history of the ’585 patent, “be made

part of this record.”

Xicor timely appealed. We have jurisdiction under 28

U.S.C. § 1295(a)(1). 3

2 The district court in SST also found that the

prosecution history of the process claims of the ’774

patent established an independent basis for holding that

Xicor had surrendered non-TEOS reactants prior to

recapturing those alternatives by claims 12 and 13 of the

RE’370 patent. See 776 F. Supp. 2d at 1085-86. In light

of our disposition, we need not reach this issue.

9 GREENLIANT SYSTEMS v. XICOR

DISCUSSION

“We review a district court’s legal determination that

a reissue patent violates the rule against recapture with-

out deference.” MBO Labs., 602 F.3d at 1312. Because

the district court decided this case on summary judgment,

we apply a de novo standard of review. Edwards

Lifesciences LLC v. Cook Inc., 582 F.3d 1322, 1335 (Fed.

Cir. 2009). Regardless of the standard applied by the

district court, we apply the correct clear and convincing

evidence standard on appeal and agree with the district

court’s result. See Yoon Ja Kim v. ConAgra Foods, Inc.,

465 F.3d 1312, 1322 (Fed. Cir. 2006).

I

As noted above, the reissue statute provides that “a

patentee may surrender a patent and seek reissue ‘enlarg-

ing the scope of the [original patent’s] claims’ if ‘through

error without any deceptive intent’ he claimed ‘less than

he had a right to claim in the [original] patent’ and he

applies for reissue ‘within two years from the grant of the

original patent.’” MBO Labs., 602 F.3d at 1313 (quoting

35 U.S.C. § 251). Under the rule against recapture, a

patentee’s reissue claims are invalid when those claims

were broadened to include subject matter that the pat-

entee previously surrendered during prosecution of the

original patent. Id. Thus, “a patentee is precluded ‘from

regaining the subject matter that he surrendered in an

3 Appellees argue that we should dismiss this case

because, in their view, Xicor’s only basis for appeal is the

summary judgment order in the SST case, and there has

been no final judgment in that case. However, this is not

a situation in which the parties stipulated that the final

result of another action be the final result here. Rather,

the parties merely agreed that a specific order in the SST

case be applied and entered in this case. Appellees’

arguments are without merit.

GREENLIANT SYSTEMS v. XICOR 10

effort to obtain allowance of the original claims.’” N. Am.

Container, 415 F.3d at 1349 (quoting Pannu v. Storz

Instruments, Inc., 258 F.3d 1366, 1370-71 (Fed. Cir.

2001)).

An assessment of a challenge under the recapture

rule is guided by three steps:

(1) first, we determine whether, and in what re-

spect, the reissue claims are broader in scope than

the original patent claims; (2) next, we determine

whether the broader aspects of the reissue claims

relate to subject matter surrendered in the origi-

nal prosecution; and (3) finally, we determine

whether the reissue claims were materially nar-

rowed in other respects, so that the claims may

not have been enlarged, and hence avoid the re-

capture rule.

N. Am. Container, 415 F.3d at 1349. Here, aside from the

removal of the TEOS limit, claims 12 and 13 of the

RE’370 patent are identical to claims 1 and 4 of the ’585

patent. The parties agree that claims 12 and 13 of the

RE’370 patent are broader than claims 1 and 4 of the ’585

patent as a result of the removal of the TEOS limit. The

parties also agree that the second step is the only step at

issue, namely, whether there was a surrender of subject

matter.

To decide whether a patentee surrendered certain

subject matter, we must determine “whether an objective

observer viewing the prosecution history would conclude

that the purpose of the patentee’s amendment or argu-

ment” concerning a particular claim was for reasons of

patentability, that is, “to overcome prior art and secure

the patent.” Kim v. ConAgra Foods, Inc., 465 F.3d 1312,

1323 (Fed. Cir. 2006). In order to surrender subject

matter through argument as opposed to claim amend-

11 GREENLIANT SYSTEMS v. XICOR

ment, a patentee “must clearly and unmistakably argue

that his invention does not cover [that] subject matter to

overcome an examiner’s rejection based on prior art.”

MBO Labs., 602 F.3d at 1314.

The parties dispute whether the prosecution history of

the method claims in the ’774 patent is relevant to

whether Xicor, in the course of the prosecution of the

device claims, surrendered devices produced through the

use of non-TEOS reactants. We do not need to reach this

question because we find that Xicor surrendered the

relevant subject matter based on the prosecution history

of the ’585 patent alone.

As noted earlier, claims 1 and 4 of the ’585 patent

were written in product-by-process form whereby the

disputed tunneling layer element in each claim was

“defined at least in part in terms of the method or process

by which it [was] made.” Bonito Boats, Inc. v. Thunder

Craft Boats, Inc., 489 U.S. 141, 158 n.* (1989) (quoting

Donald S. Chisum, Chisum on Patents § 8.05 (1988)).

“Product-by-process claims . . . enable an applicant to

claim an otherwise patentable product that resists defini-

tion by other than the process by which it is made.” In re

Thorpe, 777 F.2d 695, 697 (Fed. Cir. 1985). “In determin-

ing validity of a product-by-process claim, the focus is on

the product and not the process of making it.” Amgen Inc.

v. F. Hoffman-La Roche Ltd., 580 F.3d 1340, 1369 (Fed.

Cir. 2009). “That is because of the . . . long-standing rule

that an old product is not patentable even if it is made by

a new process.” Id. at 1370; see also SmithKline Beecham

Corp. v. Apotex Corp., 439 F.3d 1312, 1317 (Fed. Cir.

2006) (“It has long been established that one cannot avoid

anticipation by an earlier product disclosure by claiming

. . . the product as produced by a particular process.”);

Thorpe, 777 F.2d at 697 (“If the product in a product-by-

process claim is the same as or obvious from a product of

GREENLIANT SYSTEMS v. XICOR 12

the prior art, the claim is unpatentable even though the

prior product was made by a different process.”). How-

ever, there is an exception to this general rule that the

process by which the product is made is irrelevant. As we

recognized in Amgen, if the process by which a product is

made imparts “structural and functional differences”

distinguishing the claimed product from the prior art,

then those differences “are relevant as evidence of no

anticipation” although they “are not explicitly part of the

claim.” 580 F.3d at 1370; see also SmithKline, 439 F.3d at

1319 (“If those product-by-process claims produced a

different product than that disclosed by the [prior art],

there would be an argument that the [prior art] did not

anticipate.”); In re Garnero, 412 F.2d 276, 279 (CCPA

1969) (finding that certain process limits are “capable of

construction as structural . . . limitations”).

Consistent with our precedent, the Patent Office in

determining patentability considers the process in which

a product is formed if that process imparts distinctive

structural characteristics:

The structure implied by the process steps should

be considered when assessing the patentability of

product-by-process claims over the prior art, espe-

cially where the product can only be defined by

the process steps by which the product is made, or

where the manufacturing process steps would be

expected to impart distinctive structural charac-

teristics to the final product.

Manual of Patent Examining Procedure § 2113 (8th ed.

Rev. 8 July 2010) (emphasis added).

Xicor points out that it “could only have surrendered

non-TEOS reactants by making arguments or amend-

ments whose purpose ‘was to overcome prior art and

secure the patent.’” Appellant’s Br. 28 (quoting MBO

13 GREENLIANT SYSTEMS v. XICOR

Labs., 602 F.3d at 1314). Xicor also points out that “the

TEOS process limitation must have imparted novel physi-

cal characteristics to the device in order for it to distin-

guish prior art.” Appellant’s Br. 29. However, Xicor

argues, “[the TEOS] process limitation did not [actually]

impart any distinctive structural characteristics to the

claimed device.” Appellant’s Br. 30. Instead, Xicor as-

serts, it was the deposition conditions such as tempera-

ture and pressure, rather than the choice of chemical

reactants, that determined the physical characteristics of

the claimed device’s tunneling layer. Thus, according to

Xicor, it did not surrender devices produced through the

use of non-TEOS reactants. We disagree.

During the prosecution of the ’585 patent, Xicor both

amended claim 13 to add the TEOS limit and relied on

the TEOS limit appearing in claims 13 and 14 to over-

come prior art. Xicor submitted a fact declaration and

repeatedly used that declaration to argue before the

examiner, and more importantly before the Board, that

forming the claimed tunneling layer by a low pressure

chemical vapor deposition with TEOS imparted structural

differences that distinguished the claimed tunneling layer

from the prior art.

In a March 25, 1994, office action, the examiner re-

jected claims 13 and 14 of the divisional application on

multiple grounds. The examiner first rejected claims 13

and 14 as anticipated by Hazani. The examiner noted

that “Hazani shows a[] [memory] device having first and

second polycrystalline silicon layers” and a “650 Angstrom

oxide layer” through which “[o]ne can define a plane . . . to

define a ‘tunnelling layer’ and ‘thermal layer.’” J.A. 621.

The examiner also rejected claims 13 and 14 as obvious

over Sato in view of Korma. The examiner found that

Sato described a “tunnelling silicon dioxide layer [] dis-

posed between two polycrystalline silicon layers,” and

GREENLIANT SYSTEMS v. XICOR 14

Korma disclosed an oxide thickness of 1000 Angstroms,

making it obvious to use an oxide thickness under 2000

Angstroms as recited in claims 13 and 14. J.A. 622.

In conjunction with both of these rejections, the exam-

iner explained that the process limitations in the product-

by-process claims, i.e., the tunneling layer being “formed

by a low pressure chemical vapor deposition comprising

the use of [TEOS],” were “not given patentable weight

over . . . the prior art.” J.A. 621.

[T]he applicant is reminded that it is the pat-

entability of the final product per se which must

be determined in a “product by process” claim, and

not the patentability of the process, and that, as

here, an old or obvious product produced by a new

method is not patentable as a product, whether

claimed in “product by process” claims or not.

[See Thorpe, 777 F.2d 695]. The claims do not

contain any structural limitations between the

two oxide layers to make them distinguishable

from one another, i.e., different molecular density

concentrations or molecular ordering. Therefore,

although grown by different processes, the silicon

dioxide layers claimed are not distinguishable

from Sato’s.

J.A. 622. The examiner also explained:

The applicant must show the structural limita-

tions caused from the process of making the de-

vice. The matter given weight in claims drawn to

structure having “process of making” segments

are those present in the final product, and here,

after forming one oxide layer on another, one can-

not distinguish separate tunnelling and thermal

oxide layers in the final product.

15 GREENLIANT SYSTEMS v. XICOR

J.A. 623-24.

On August 29, 1994, Xicor’s response to the exam-

iner’s rejection was received by the Patent Office. Xicor

made no further amendments to claim 13 or 14, which, by

this time, both included the TEOS limit. However, Xicor

argued that its claimed invention, including a “deposited

TEOS oxide layer,” was “structurally distinct from the

prior art thermal oxide layers taught by Hazani and

Sato.” J.A. 628.

Xicor pointed to “characteristics of the claimed device

[that] are clearly different and superior to the prior art

thermal oxide layers,” and thus, in Xicor’s view, evidenced

structural differences between the prior art and the

claimed TEOS deposited tunneling oxide layer. J.A. 631.

With respect to improved dielectric properties, Xicor

argued:

[The inventor] found that low temperature depos-

ited dielectrics, properly annealed, are better than

thermal oxides for tunneling. For example, . . .

the inventor discovered that TEOS tunneling ox-

ides formed in the manner claimed in this case in-

crease the total charge which can be conducted

through a dielectric layer by at least an order of

magnitude while at the same time providing a

dramatic improvement in processing yields.

J.A. 629. Further, with respect to stress, Xicor argued:

It is well known that thermally grown oxide lay-

ers create heavy compressive stress. It is well

known that TEOS deposited layer can be defined

to induce either compressive or tensile stress, and

be of a much lower magnitude than for thermally

grown oxide. Consequently, stress can be mini-

mized when using a TEOS deposited tunneling ox-

GREENLIANT SYSTEMS v. XICOR 16

ide layer. This provides the advantage of a device

having a much greater useful life.

J.A. 630 (internal quotation marks omitted). Finally,

with respect to pinhole defects, Xicor argued:

[P]inholes are often created in a thermal oxide

layer as a result of small metallic impurities in

the underlying silicon or polysilicon layer. The

TEOS deposited layer coats all surfaces and thus

will fill in such pinholes . . . .

J.A. 630 (internal quotation marks omitted). Due to these

improved characteristics, Xicor asserted, “the industry

has acknowledged that the use of deposited TEOS oxide

has significant structural benefits over prior art thermal

oxide layers when used as tunneling layers.” J.A. 632.

On November 15, 1994, the examiner again rejected

claims 13 and 14, among others, as being anticipated by

Hazani, and in the alternative, as obvious over Sato in

view of Korma. Xicor subsequently appealed to the

Board. Before the Board, Xicor urged that the “prior art

devices . . . d[id] not possess the characteristics and

structure of Appellant’s claimed device,” J.A. 656, and

repeated the arguments that it had made to the examiner

regarding the improved dielectric properties, reduced

stress, and reduced defect densities of the claimed TEOS

deposited tunneling oxide layer. J.A. 657-61. With re-

spect to the anticipation and obvious rejections, Xicor

argued:

The structure of the tunneling oxide layer accord-

ing to the present invention is significantly differ-

ent from prior art tunneling oxide layers since the

inventive layer substantially reduces stress and

defect density. Forming TEOS tunneling oxides in

the manner claimed by [Xicor] increases the total

17 GREENLIANT SYSTEMS v. XICOR

charge which can be conducted through a dielec-

tric layer by at least an order of magnitude while

at the same time providing a dramatic improve-

ment in processing yields. The Examiner has not

shown that the cited references, alone or in com-

bination, suggest or teach this process or its ad-

vantages.

J.A. 661 (emphasis added). Moreover, in order to distin-

guish a prior art reference that found another type of

deposition preferable to TEOS deposition for forming an

insulation layer, Xicor specifically argued that “one

skilled in the art would not have been motivated to use

TEOS for oxide deposition.” J.A. 663.

On June 3, 1999, the Board reversed the examiner’s

rejections of claims 13 and 14, among others. The Board

understood Xicor’s arguments to be directed to the TEOS

limit, noting that “[t]he only issue on appeal is the weight

to be given to the process step of ‘said silicon dioxide layer

being formed by low pressure chemical vapor deposition

comprising the use of [TEOS].’” J.A. 726-27. The Board

held:

The foregoing advantages of TEOS deposited ox-

ides versus thermally grown oxides . . . are suffi-

cient to establish unobvious differences between

the claimed product and the prior art.

J.A. 731-32 (emphasis added).

Xicor’s arguments clearly and unmistakably repre-

sented to the examiner and the Board that TEOS was a

necessary component of the deposition process that im-

parted the distinct structural characteristics upon Xicor’s

claimed tunneling oxide layer. There is no merit to Xi-

cor’s argument that these multiple references to the use of

TEOS can be dismissed as mere “nomenclature . . . used

GREENLIANT SYSTEMS v. XICOR 18

by Xicor as a label to distinguish” between different

tunneling layers. Appellant’s Br. 60. It is clear that “an

objective observer viewing the prosecution history would

conclude” that Xicor had surrendered devices produced

through the use of non-TEOS reactants during the prose-

cution of the ’585 patent to overcome prior art and secure

the patent. Kim, 465 F.3d at 1323. Under the rule

against recapture, Xicor cannot now reclaim that surren-

dered subject matter. Pannu, 258 F.3d at 1370-71.

Xicor argues that, as a technical matter, “it is the

deposition conditions—such as temperature and pres-

sure—that determine the physical characteristics” of the

claimed tunneling oxide layer, not the reactant, such as

TEOS, that is used. Appellant’s Br. 54. Thus, according

to Xicor, the TEOS limit could not have influenced the

Board’s decision to allow the claims. But Xicor is bound

by the arguments that it made before the examiner and

before the Board. It does not matter whether the exam-

iner or the Board adopted a certain argument for allow-

ance; the sole question is whether the argument was

made. See, e.g., Springs Window Fashions LP v. Novo

Indus., L.P., 323 F.3d 989, 995 (Fed. Cir. 2003) (holding

that though “it is not clear from the record why the exam-

iner allowed the claims,” the examiner’s reasons for

allowance “do not negate the effect of the applicant’s

disclaimer”). Nor does it matter here whether TEOS

actually imparted the cited structural differences because

Xicor argued that it did.

This principle is well established by our cases on

prosecution history disclaimer, a doctrine that “serves the

same policy” as the recapture rule, i.e., “prevent[ing] a

patentee from encroaching back into territory that had

previously been committed to the public.” MBO Labs.,

602 F.3d at 1318 (internal quotation marks omitted); see

also Hester Indus., Inc. v. Stein, Inc., 142 F.3d 1472, 1482

19 GREENLIANT SYSTEMS v. XICOR

(Fed. Cir. 1998). In North American Container, for exam-

ple, the patentee distinguished the “generally convex”

inner walls of his invention from prior art that, as the

patentee characterized it, contained “wall portions 3

[that] are slightly concave.” 415 F.3d at 1343 (emphasis

added). Thus, we held that “generally convex” not only

required that the majority of points along the claimed

walls were convex, but also that no portions along the

claimed walls were concave. Id. at 1345-46. The patentee

argued that, during prosecution, he “intended only to

distinguish his invention from the prior art on the basis

that the inner walls in the prior art bottles [we]re entirely

concave.” Id. But regardless of any technical merit

behind the newly explained distinction, we held that the

patentee was bound by arguments actually made during

prosecution. Id. at 1346. “Although the inner walls

disclosed in the [prior art] patents may be viewed as

entirely concave, that is not what the applicant argued

during prosecution to gain allowance for his claims.” Id.

Here, Xicor is bound by the arguments it made during

the prosecution of the ’585 patent, which clearly establish

that it surrendered devices produced through the use of

non-TEOS reactants for the recited low pressure chemical

vapor deposition in order to gain allowance. Thus, we

affirm the district court’s holding that claims 12 and 13 of

the RE’370 patent are invalid under the rule against

recapture.

AFFIRMED

COSTS

No costs.