United States Court of Appeals for the Federal Circuit 

04-1013 

ALFRED SALAZAR, 

Plaintiff-Appellant, 

v. 

PROCTER & GAMBLE COMPANY, 

Defendant-Appellee. 

Henry C. Su, Fenwick & West LLP, of Mountain View, California, argued for 

plaintiff-appellant. With him on the brief were Brenda M. Simon and Kent Kemeny. 

Charles J. Faruki, Faruki Ireland & Cox P.L.L., of Dayton, Ohio, argued for 

defendant-appellee. With him on the brief was Thomas R. Kraemer. 

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

Senior Judge H. Dale Cook 
United States Court of Appeals for the Federal Circuit

 

04-1013 

ALFRED SALAZAR, 

 Plaintiff-Appellant, 

v. 

PROCTER & GAMBLE COMPANY, 

 Defendant-Appellee. 

___________________________ 

 DECIDED: July 8, 2005 

___________________________ 

Before RADER, BRYSON, and GAJARSA, Circuit Judges. 

Opinion for the court filed by Circuit Judge RADER. Dissenting opinion filed by Circuit 

Judge BRYSON. 

RADER, Circuit Judge. 

Alfred Salazar owns U.S. Patent No. 5,535,474 (’474 patent) for a toothbrush 

having polishing rods that clean and polish the teeth and stimulator rods that stimulate 

the gums during brushing. ’474 patent, Abstract. Salazar, acting pro se, sued Proctor & 

Gamble Co. (Proctor & Gamble) for infringement of the ’474 patent. Proctor & Gamble 

moved for summary judgment because its toothbrushes do not include the “elastic” 

feature of claim 1, the only independent claim of the ’474 patent. On September 8, 

2003, the district court issued an order construing the “elastic” limitation and granting 

summary judgment to Proctor & Gamble because its products do not infringe literally or 

under the doctrine of equivalents. Salazar v. Procter & Gamble Co., No. 02-CV-590-C 

(N.D. Okla. Sept. 8, 2003) (Order). Because the district court erred in using the patent 
examiner’s Reasons of Allowance to exclude nylon from the scope of the claim term 

“elastic,” this court vacates the grant of summary judgment and remands. 

I 

Mr. Salazar submitted U.S. Patent Application No. 409,149 (’149 application) on 

March 23, 1995, which eventually matured into the ’474 patent. The ’474 patent claims a 

toothbrush with, inter alia, elastic stimulator rods and elastic polishing rods that extend 

above the bristles of the brush. ’474 patent, col. 5, l. 30 – col. 6, l. 23. The ’149 

application initially contained an independent claim 1 and five dependent claims. Claim 

2 of the ’149 application depended from claim 1; and claim 3 from claim 2. The examiner 

rejected claim 1 as obvious over U.S. Patent No. 3,072,944 (issued Jan. 15, 1963) to 

Clayton (Clayton) in light of U.S. Patent No. 3,103,679 (issued Sept. 17, 1963) to 

Clemens (Clemens). The examiner objected to claims 2 and 3 as allowable subject 

matter dependent upon a rejected base claim. 

The applicant responded by canceling claims 1-3 and introducing a new claim 7 

based on the allowable subject matter of claim 3. The examiner allowed claim 7 without 

rejection,1

 which issued as claim 1 of the ’474 patent. In the Notice of Allowance, the 

examiner made the following remarks in the Examiner’s Statement of Reasons for 

Allowance: 

Claim 7 now incorporates previously held allowable subject matter . . . . 

Although the patent to Clemens appears to have the recited structure, 

Clemens’ “rods” 22 are made of nylon, which is not considered “elastic”. 

Obviously the “rods” of Clemens are flexible, but are not considered to be 

“elastic” as recited by the claim. 

 1 Although claim 7 was not rejected, the examiner made amendments to 

claim 7 not pertinent to this appeal. 

04-1013 2
The applicant did not respond to these remarks by the examiner. The ’474 patent issued 

with claim 7 renumbered as claim 1. 

Mr. Salazar sued Procter & Gamble alleging infringement of certain claims of the 

’474 patent. Procter & Gamble filed a motion for summary judgment of no infringement 

either literally or under the doctrine of equivalents. Proctor & Gamble contended that the 

stimulator and polishing rods in its products are not “elastic” as required by claim 1. The 

district court construed the term “elastic” and granted Procter & Gamble’s motion for 

summary judgment. Order at 5 & 7. Specifically, the district court construed the term 

“elastic” as “any material other than nylon, capable of returning to an initial state or form 

after deformation.” Order at 5 (internal quotation and citation omitted). 

The district court granted summary judgment of no infringement because Mr. 

Salazar did not present sufficient evidence to raise an issue of fact about the elasticity of 

the stimulator and polishing rods in the accused products. Id. at 7. Thus, the district 

court concluded that the accused products did not fall within the court’s interpretation of 

the claim term “elastic.” Id. The district court also found that the doctrine of prosecution 

history estoppel barred Mr. Salazar from asserting infringement of the “elastic” limitation 

under the doctrine of equivalents. Id. at 6. Mr. Salazar appeals. 

II. 

A determination of infringement requires a proper interpretation of the scope and 

meaning of the claim followed by a comparison of the accused product to that claim 

scope. Omega Eng’g, Inc. v. Raytek Corp., 334 F.3d 1314, 1320 (Fed. Cir. 2003); 

Carroll Touch, Inc. v. Electro Mech. Sys., Inc., 15 F.3d 1573, 1576 (Fed. Cir. 1993). In 

the context of a grant of summary judgment of no infringement, this court reviews the 

04-1013 3
entire infringement inquiry without deference. Omega Eng’g, 334 F.3d at 1320. 

“Summary judgment is therefore appropriate when there is no genuine issue of material 

fact or when, drawing all factual inferences in favor of the nonmoving party, no 

‘reasonable jury could return a verdict for the nonmoving party.’” Id. (citing Anderson v. 

Liberty Lobby, Inc., 477 U.S. 242, 248 (1986)). 

In construing claims, “[t]his court . . . considers the prosecution history to 

determine whether the applicant clearly and unambiguously disclaimed or disavowed 

any interpretation during prosecution in order to obtain claim allowance.” 3M Innovative 

Props. Co. v. Avery Dennison Corp., 350 F.3d 1365, 1371 (Fed. Cir. 2003) (internal 

quotations and alterations omitted); accord Omega Eng’g, 334 F.3d at 1324; Middleton, 

Inc. v. Minn. Mining & Mfg. Co., 311 F.3d 1384, 1388 (Fed. Cir. 2002); Standard Oil Co. 

v. Am. Cyanamid Co., 774 F.2d 448, 452 (Fed. Cir. 1985). 

The doctrine of prosecution history estoppel serves to limit the doctrine of 

equivalents when the applicant makes a narrowing amendment for purposes of 

patentability, or clearly and unmistakably surrenders subject matter by arguments made 

to the examiner. See Festo Corp. v. Shoketsu Kinzoku Kogyo Kabushiki Co., 535 U.S. 

722, 736 (2002) (narrowing amendment for purposes of patentability); Eagle Comtronics, 

Inc. v. Arrow Communication Labs., Inc., 305 F.3d 1303, 1316 (Fed. Cir. 2002) 

(argument-based estoppel); Elaky Mfg. Co. v. Ebco Mfg. Co., 192 F.3d 973, 979 (Fed. 

Cir. 1999) (argument-based estoppel). 

The first and only time the examiner discussed the “elastic” limitation was in the 

Examiner’s Statement of Reasons for Allowance. The examiner did not at any time 

reject a claim of the ’149 application containing the “elastic” limitation as anticipated or 

04-1013 4
obvious in view of the prior art.2

 Other than the remarks in the Examiner’s Statement of 

Reasons for Allowance, the prosecution history does not contain any discussion of the 

“elastic” limitation by either the examiner or the applicant. Nonetheless, the district court 

excluded nylon from the scope of “elastic.” Order at 5. Specifically, the district court 

found that the remarks in the Examiner’s Statement of Reasons for Allowance “amended 

the claim specifically to exclude nylon from the definition of ‘elastic.’” Id. Thus, this 

appeal requires this court to decide whether unilateral statements of an examiner in 

stating reasons for allowance can create a clear and unambiguous disavowal of claim 

scope and give rise to prosecution history estoppel. 

The regulations in force during the prosecution of the ’149 application state: 

If the examiner believes that the record of the prosecution as a whole 

does not make clear his or her reasons for allowing a claim or claims, the 

examiner may set forth such reasoning. The reasons shall be 

incorporated into an office action rejecting other claims of the application 

or patent under reexamination or be the subject of a separate 

communication to the applicant or patent owner. The applicant or patent 

owner may file a statement commenting on the reasons for allowance 

within such time as may be specified by the examiner. Failure to file such 

a statement shall not give rise to any implication that the applicant or 

patent owner agrees with or acquiesces in the reasoning of the examiner.

37 C.F.R. § 1.109 (1996) (emphasis added).3

 These regulations offer the applicant an 

opportunity to respond to the examiner’s unilateral reasons for allowance. The 

regulations also state, however, that the applicant does not acquiesce in those reasons if 

the applicant declines to respond. 

 2 Claims of the ’149 application containing the “elastic” limitation were 

rejected by the examiner for reasons not pertinent to this appeal. 

3

 37 C.F.R. § 1.109 has since been amended and now appears at 37 C.F.R. 

§ 1.104(e) (2003). 

04-1013 5
This court has recognized that an Examiner’s Statement of Reasons for 

Allowance “will not necessarily limit a claim.” ACCO Brands, Inc. v. Micro Sec. Devices, 

Inc., 346 F.3d 1075, 1079 (Fed. Cir. 2003). Consequently, an applicant’s silence 

regarding statements made by the examiner during prosecution, without more, cannot 

amount to a “clear and unmistakable disavowal” of claim scope. See 3M Innovative 

Props., 350 F.3d at 1373-74 (“‘Prosecution history . . . cannot be used to limit the scope 

of a claim unless the applicant took a position before the PTO.’ Schwing GmbH v. 

Putzmeister Aktiengesellschaft, 305 F.3d 1318, 1324-25 (Fed. Cir. 2002) (emphasis 

added). An applicant’s silence in response to an examiner’s characterization of a claim 

does not reflect the applicant’s clear and unmistakable acquiescence to that 

characterization if the claim is eventually allowed on grounds unrelated to the examiner’s 

unrebutted characterization.”). After all, the applicant has disavowed nothing. 

Procter & Gamble concedes that the law precludes drawing inferences from an 

applicant’s decision to decline comment on an Examiner’s Statement of Reasons for 

Allowance, yet argues that Mr. Salazar should be bound by “the message he sent to the 

public” by his silence. 

Procter & Gamble supports its position with this court’s language that, on its face, 

appears to support Procter & Gamble. However, a closer inspection of those cases 

reveals that Procter & Gamble either cites to dicta or to cases addressing issues 

different from this case. Procter & Gamble first quotes TorPharm Inc. v. Ranbaxy 

Pharmaceuticals, Inc., 336 F.3d 1322, 1330 (Fed. Cir. 2003): 

Whether the patentee chooses to dispute the examiner’s view of matters 

is relevant to claim interpretation, for there a court may need to ascertain 

exactly what subject matter was actually examined and allowed by the 

PTO. Patent examination would serve little purpose unless the scope of 

04-1013 6
the exclusive patent right correlated with the matter allowed by the PTO. 

Accordingly, in ascertaining the scope of an issued patent, the public is 

entitled to equate an inventor’s acquiescence to the examiner’s narrow 

view of patentable subject matter with abandonment of the rest. Such 

acquiescence may be found where the patentee narrows his or her claims 

by amendment, or lets stand an examiner’s restrictive interpretation of a 

claim. 

(internal citations omitted) (emphases supplied by Procter & Gamble). TorPharm

addresses a different issue from that before this court. In TorPharm, the applicant added 

limitations to claims to overcome an obviousness rejection. Later during litigation, the 

defendant discovered and showed that the added limitation was also in the prior art. The 

defendant asserted that the patentee had acquiesced in the obviousness of its invention 

by amending its claims. Therefore, according to the defendant, the patentee could not 

challenge its obviousness contentions. This court in TorPharm held that the applicant’s 

“acquiescence” in the obviousness rejection by amending its claims did not preclude the 

patentee from contesting obviousness in litigation. Id. at 1331. Thus, TorPharm does 

not hold that a patentee’s silence in the face of an examiner’s unilateral statements in a 

Notice of Allowance amounts to a clear disavowal of claim scope. 

Procter & Gamble next quotes the following passage from Inverness Medical 

Switzerland GmbH v. Princeton Biomeditech Corp., 309 F.3d 1365, 1372 (Fed. Cir. 

2002): 

[E]ven where the ordinary meaning of the claim is clear, it is wellestablished that the prosecution history limits the interpretation of claim 

terms so as to exclude any interpretation that was disclaimed during 

prosecution. A broader definition may be disclaimed, for example, where 

the examiner adopts a narrow definition and the applicant does not object. 

(internal quotations and citations omitted). This broad language, however, is merely 

dicta. Inverness actually rejected the appellee’s argument that a statement in the 

04-1013 7
examiner’s Reasons for Allowance governed the construction of the claim term at issue. 

Id. at 1373. 

Moreover, the cited quotations from both TorPharm and Inverness rely on Elkay. 

In Elkay, the examiner rejected some claims in the application for obviousness. 192 

F.3d at 978. In response, the applicant did not substantially amend the claims, but 

overcame the rejection by arguing around the prior art cited by the examiner. Id. At trial, 

the patentee discounted its own prosecution arguments that had overcome the 

examiner’s obviousness rejection. The patentee sought to show that those arguments 

were insignificant and should not provide a basis to narrow the scope of the claims. Id.

at 979. This court rejected the patentee’s argument. In crediting the applicant’s 

narrowing arguments during prosecution, this court noted that the examiner expressly 

accepted those arguments in the Statement of Reasons for Allowance. Id. Thus, Elkay

holds that the Examiner’s Statement of Reasons for Allowance may help show that the 

applicant’s own arguments during prosecution constitute a clear disavowal of claim 

scope. See also Lemelson v. Gen. Mills, Inc., 968 F.2d 1202, 1207 (Fed. Cir. 1992) 

(holding that a patentee acquiescing in an examiner’s rejection of a broad claim by filing 

narrower claims cannot later regain the broader scope previously abandoned); ACCO 

Brands, 346 F.3d at 1079 (relying on comments made in an Examiner’s Statement for 

Reasons of Allowance to limit claim scope because “in this case the examiner simply 

repeated the arguments that the patentee had presented”). 

In sum, Procter & Gamble does not present any case law that stands for the 

proposition that an examiner’s unilateral statements in a Notice of Allowance constitute a 

clear and unambiguous disavowal of claim scope. Once again, the applicant has 

04-1013 8
disavowed nothing. This court refuses to create a rule or presumption that the applicant 

in this case disavowed claim scope by silence. 

Procter & Gamble admits that Mr. Salazar was not required to answer the 

examiner’s statement, but argues that “it does not follow that the patent examiner’s 

comments then should be ignored.” Although unilateral statements by an examiner do 

not give rise to a clear disavowal of claim scope by an applicant, it does not necessarily 

follow that such statements are not pertinent to construing claim terms. Statements 

about a claim term made by an examiner during prosecution of an application may be 

evidence of how one of skill in the art understood the term at the time the application was 

filed. However, as explained above, an applicant’s silence regarding such statements 

does not preclude the applicant from taking a position contrary to the examiner’s 

statements when the claim terms are construed during litigation. 

The district court relied upon the same remarks in the Examiner’s Statements for 

Reasons of Allowance to find that prosecution history estoppel bars Mr. Salazar from 

asserting infringement of the “elastic” element under the doctrine of equivalents. Order

at 6-7. Although the claim language was not altered in response to the examiner’s 

remarks in the Examiner’s Statement for Reasons of Allowance, the district court found 

that the examiner’s remarks “amended” the “elastic” element of the claim. Id. at 7. 

However, as previously discussed, this court finds that the examiner’s unilateral remarks 

did not alter the scope of the claim.4

 An examiner’s statement cannot amend a claim. 

 4 The parties do not dispute that introducing claim 7 based on the allowable 

subject matter of dependent claim 3 of the ’149 application was not a narrowing 

amendment for purposes of patentability and, therefore, does not by itself give rise to 

prosecution history estoppel. See Festo Corp. v. Shoketsu Kinzoku Kogyo Kabushiki 

04-1013 9
Consequently, the district court clearly erred in finding that claim 1 was “amended.” 

Moreover, as the regulation and this court’s reasoning above discuss, the examiner’s 

unilateral remarks alone do not affect the scope of the claim, let alone show a surrender 

of claimed subject matter that cannot be recaptured under the doctrine of equivalents. 

Thus, this court reverses the district court’s holding that prosecution history bars Mr. 

Salazar from asserting infringement of the “elastic” element under the doctrine of 

equivalents. 

The parties only contest whether the applicant’s silence to the examiner’s remarks 

in the Examiner’s Statements of Reasons for Allowance amounts to a clear disavowal of 

claim scope as found by the district court. Because such statements do not amount to a 

clear disavowal of claim scope by the applicant, this court vacates the portion of the 

district court’s claim construction excluding nylon from falling within the scope of the 

“elastic” element. This court affirms the remaining portion of the district court’s claim 

construction that “elastic” means “capable of returning to an initial state or form after 

deformation.” Whether the accused products satisfy the “elastic” limitation in the 

asserted claims is a factual matter that this court leaves for the district court to resolve in 

the first instance. 

III 

This court vacates the district court’s grant of summary judgment of no literal 

infringement and no infringement under the doctrine of equivalents. The district court’s 

claim construction excluding nylon from the scope of the “elastic” element is also 

vacated. This court affirms the remaining portion of the district court’s claim construction 

 

Co., 535 U.S. 722, 736 (2002) (stating that an amendment that is “truly cosmetic” does 

not give rise to prosecution history estoppel). 

04-1013 10
of “elastic.” This case is remanded to the district court for further proceedings consistent 

with this opinion. 

COSTS

Each party shall bear its own costs. 

VACATED-IN-PART, AFFIRMED-IN-PART, and REMANDED

04-1013 11
United States Court of Appeals for the Federal Circuit

04-1013 

ALFRED SALAZAR, 

Plaintiff-Appellant, 

v. 

PROCTER & GAMBLE COMPANY, 

Defendant-Appellee. 

BRYSON, Circuit Judge, dissenting. 

 I respectfully dissent. The ’474 patent distinguishes between the stimulator rod 

and the bristles that are mounted together in recessed sockets in the Salazar 

toothbrush. It states that the bristles are typically “composed of conventional bristle 

material such as nylon,” while the stimulator rod “is composed of an elastic material, 

typically rubber or rubber substitute.” ’474 patent, col. 4, ll. 31-34. The patent thus 

suggests that the stimulator rod and the bristles are made of different materials, which 

contributes to the differences in their functions. In light of the disclosure in the patent, it 

was unsurprising that the examiner understood the Salazar stimulator rods to be made 

of a substance other than nylon, and that he based his distinction of the prior art 

Clemens patent on that ground. 

 It is true that, in general, an inventor has no affirmative obligation to respond to 

an examiner’s characterization of a claim. That is, an applicant is not bound by every 

statement made by an examiner during the course of the prosecution unless the 
04-1013 2 

applicant corrects the statement on the record. We have held, for example, that an 

applicant’s silence in response to an examiner’s characterization of a claim “does not 

reflect the applicant’s clear and unmistakable acquiescence to that characterization if 

the claim is eventually allowed on grounds unrelated to the examiner’s unrebutted 

characterization.” 3M Innovative Props. Co. v. Avery Dennison Corp., 350 F.3d 1365, 

1373-74 (Fed. Cir. 2003). In this case, however, the examiner’s statement related 

directly to the ground on which the patent was issued. More importantly, the statement 

is relevant not because it serves as the basis for a finding of disclaimer by the inventor, 

but because it indicates how a person of ordinary skill in the art—in this instance, the 

examiner—would understand the claim term “elastic” in the context of the patent. When 

an applicant sits idly by while an examiner explains that he understands particular claim 

language to have a particular meaning and only regards the invention as patentable 

based on that meaning, the applicant should face a heavy burden in later challenging 

the examiner’s interpretation. That principle is what I understand to underlie the court’s 

statement in Torpharm, Inc. v. Ranbaxy Pharmaceuticals, Inc., 336 F.3d 1322, 1330 

(Fed. Cir. 2003), that “an inventor’s acquiescence to the examiner’s narrow view of 

patentable subject matter” may be found where the patentee “lets stand an examiner’s 

restrictive interpretation of a claim.” The examiner’s statement in Elkay Manufacturing 

Co. v. Ebco Manufacturing Co., 192 F.3d 973, 979 (Fed. Cir. 1999), is to the same 

effect. There, the unresponded-to examiner’s statement was relevant because it 

indicated that the examiner had relied on the patentee’s distinction of a prior art 

reference in allowing the claim in suit. In this case, likewise, the examiner made clear 

his understanding of the meaning of the term “elastic” as used in the patent; in that 
04-1013 3 

setting, and in light of the central importance of the examiner’s understanding of the 

meaning of the term to his decision to allow the claims, the absence of any indication 

that the patentee intended the claim term to be broader supports the district court’s 

conclusion that the “elastic” stimulator rods should not be construed to include rods 

made of nylon.