1

IN THE UNITED STATES DISTRICT COURT

FOR THE NORTHERN DISTRICT OF ILLINOIS

EASTERN DIVISION

COSTAR REALTY INFORMATION, INC., )

)

Plaintiff, )

)

v. ) No. 12 C 4968

)

CIVIX-DDI, LLC, )

)

Defendant. )

_________________________________________ )

)

CIVIX-DDI, LLC, )

)

Plaintiff, )

) No. 12 C 7091

v. )

)

LOOPNET, INC., )

)

Defendant. )

_________________________________________ )

)

CIVIX-DDI, LLC, )

)

Plaintiff, )

) No. 12 C 8632

v. )

)

LOOPNET, INC., )

)

Defendant. )

MEMORANDUM ORDER AND OPINION

JAMES F. HOLDERMAN, Chief Judge:

These three consolidated patent cases involve allegations of patent infringement by patent 

holder CIVIX-DDI, LLC (“CIVIX”) against CoStar Realty Information, Inc. (“CoStar”) and 
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LoopNet, Inc. (“LoopNet”). In 12 C 4968, CIVIX alleges that CoStar has infringed three of its

patents, U.S. Patent No. 6,385,622 (“the ‘622 Patent”), U.S. Patent No. 6,415,291 (“the ‘291 

Patent”), and 8,296,335 (“the ’335 Patent”). (Dkt. No. 108 (“CIVIX’s Countercl.”).) CoStar 

alleges that the ‘622 Patent, the ‘291 Patent, and the ‘335 Patent are all unenforceable because of 

inequitable conduct. (Dkt. No. 99 (“CoStar’s Third Am. Compl.”).) Similarly, in 12 C 8632, 

CIVIX alleges that LoopNet infringed the ‘335 Patent. (12 C 8632, Dkt. No. 1 (“CIVIX’s 

Compl.”).) In response, LoopNet alleges that the ‘335 Patent is unenforceable because of 

inequitable conduct. (12 C 8632, Dkt. No. 71 (“Loopnet’s Second Am. Countercl.”).)

CIVIX has now moved to dismiss both CoStar’s (Dkt. No. 109) and LoopNet’s (Dkt. No. 

112) allegations that its patents are unenforceable. CIVIX’s motion to dismiss against LoopNet 

also seeks to strike LoopNet’s Sixth Affirmative Defense, which also alleges inequitable conduct. 

(Dkt. No. 112.) Because the allegations of inequitable conduct are substantively identical in each 

case, the court will address the two motions to dismiss together. For the reasons explained below, 

CIVIX’s motions to dismiss are each granted in part and denied in part.

FACTUAL BACKGROUND

CIVIX is the owner of the ‘622 and ‘291 Patents, both of which claim methods to locate 

points of interest in a particular geographical region by accessing a database from a remote 

location, and of the ‘335 Patent, which claims methods for using the Internet to provide a user of 

such a database advertising information related to the requested geographic region or item of 

interest. (See Dkt. No. 99, Exs. A, B, & F.) 
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CoStar’s allegations regarding inequitable conduct are substantively identical to 

LoopNet’s allegations regarding inequitable conduct.1 For ease of reference, the following factual 

summary refers only to CoStar’s Third Amended Complaint (Dkt. No. 99), the allegations of 

which the court accepts as true for purposes of these motions to dismiss.2

I. Alleged Inequitable Conduct in Prosecution of ‘622 and ‘291 Patents

Both the ‘622 and ‘291 Patents were filed on March 23, 2001, as continuations of United 

States Patent Nos. 5,682,525 (“the ‘525 Patent”) and 6,408,307 (“the ‘307 Patent). (CoStar’s Third 

Am. Compl. ¶ 68; see also id. Exs. A-B.) The ‘622 Patent issued on May 7, 2002 (Id. Ex. A), and 

the ‘291 Patent issued on July 2, 2002 (Id. Ex. B). The inventors of the ‘622 Patent and the ‘291 

Patent are W. Lincoln Bouve, William T. Semple, and Steven W. Oxman.

CoStar alleges that the prosecution histories for the ‘622 and ‘291 Patents indicate that 

CIVIX failed to inform the PTO of certain prior proceedings involving the ‘525 and ‘307 Patents. 

The proceedings that CoStar alleges were omitted include a lawsuit against Navigation 

Technologies Corporation (“NavTech”) in the Northern District of Illinois for infringement of the 

‘525 Patent (Id. ¶ 69), an interference application filed by NavTech before the PTO seeking to be 

declared the first inventor of the technology claimed in the ‘525 Patent (Id. ¶ 70), and a lawsuit 

 1 Paragraphs 107-38 of CoStar’s Third Amended Complaint (Dkt. No. 99) are 

substantively identical to ¶¶ 31-62 of LoopNet’s Second Amended Answer and Counterclaims (12 

C 8632, Dkt. No. 71). In addition, ¶ 31 of LoopNet’s Second Amended Answer and Counterclaims 

(12 C 8632, Dkt. No. 71) incorporates by reference ¶¶ 43-84 of LoopNet’s Second Amended 

Answer and Counterclaims in 12 C 7091 (12 C 7091, Dkt. No. 138), which are substantively 

identical to ¶¶ 65-105 of CoStar’s Third Amended Complaint (Dkt. No. 99). 

2 Throughout this opinion, references to “CoStar” and “CoStar’s allegations” refer also to 

“LoopNet” and “LoopNet’s allegations.”
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against Microsoft Corp. in the District of Colorado3 for infringement of the ‘525 Patent (Id.

¶¶ 73-74). CoStar alleges, in particular, that CIVIX failed to disclose to the PTO that the court in 

the Microsoft litigation construed terms in the ‘525 Patent that are also in the ‘622 and ‘291 

Patents, and granted summary judgment of non-infringement of the ‘525 Patent. (Id. ¶ 74.) CoStar 

alleges that CIVIX had the “specific intent” to deceive the PTO by failing to disclose the above 

information. (Id. ¶¶ 72, 77.) 

On November 5, 1999, Microsoft moved for summary judgment that the ‘525 Patent was 

invalid in the Microsoft litigation on the basis of three prior art references. (Id. ¶ 78.) At the time, 

CIVIX’s application for the ‘307 Patent was pending.4 CIVIX’s ‘307 Patent application included 

three prior Information Disclosure Statements (“IDSs”), but none of those three IDSs included any 

of the prior art that Microsoft contended invalidated the ‘525 Patent. (Id. ¶¶ 78-79.) Fifteen months 

after Microsoft’s motion for summary judgment of invalidity, CIVIX filed a fourth IDS as part of 

its application for the ‘307 Patent. (Id. ¶ 80.) The fourth IDS referred to the prior art on which 

Microsoft relied, but did so in the middle of “a mountain of material,” including 244 patents, 64 

patent applications, and 290 non-patent references. (Id.) The PTO requested that CIVIX identify 

the most relevant material among those references, but CIVIX failed to identify the three 

references on which Microsoft relied in its invalidity argument. (Id. ¶¶ 81-82.) 

The IDS CIVIX submitted on January 17, 2002, as part of its prosecution of the ‘291 Patent 

included approximately 600 references. (Id. ¶ 85.) CIVIX did not, however, submit an IDS as part 

 3 See CIVIX v. Microsoft Corp., 84 F. Supp. 2d 1132 (D. Colo. 2000). 

4 The ‘307 Patent application was filed on August 28, 1997, and the ‘307 Patent issued on 

June 18, 2002. 
5

of its prosecution of the ‘622 Patent. (Id. ¶ 86.) CoStar alleges that CIVIX’s decisions to submit an 

excessive number of references and not to submit any IDS, respectively, were driven by the 

specific intent to deceive and mislead the PTO. (Id. ¶ 87.)

CoStar alleges that CIVIX’s deceit continued during the reexaminations of the ‘622 and 

‘291 Patents. During those processes, on January 21, 2009, CIVIX submitted a declaration signed 

by Bouve and Semple “describ[ing] the circumstances surrounding the claimed invention so as to 

establish a priority date that antedates a dispositive prior art reference” (the “Bouve Declaration”).

(Id. ¶ 89.) Prior to submitting the Bouve declaration, however, Bouve had suffered at least two 

strokes, had substantial memory loss, and had difficulty speaking intelligibly. (Id. ¶ 91.) Although 

CIVIX’s counsel were aware of Bouve’s condition because they had previously stated that he was 

unfit for depositions because of his health problems, the Bouve Declaration did not disclose 

Bouve’s health issues. (Id. ¶¶ 91-92.) Moreover, despite other counsel bringing the matter to its 

attention, CIVIX never informed the PTO of the unreliability of the Bouve Declaration. (Id.

¶¶ 93-94.) Nonetheless, CIVIX submitted a supplemental declaration by Semple, attesting to 

essentially the same facts as the Bouve Declaration, on May 8, 2009. (Id. ¶ 96.) CoStar alleges that 

CIVIX had the specific intent to deceive the PTO by failing to disclose Bouve’s health issues, that 

CIVIX concealed its wrongdoing by submitting a later declaration without Bouve’s signature, and 

that the PTO would have found the information important in deciding whether the ‘622 and ‘291 

Patents survived reexamination. (Id. ¶¶ 95, 97.) 

On January 21, 2009, Semple submitted another declaration on behalf of CIVIX as part of 

the reexamination proceedings for the ‘622 and ‘291 Patents explaining his understanding that the 

terms “Internet” and “internet” had the same meaning at the time of the invention. (Id. ¶¶ 98-99.) 
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That declaration contradicted CIVIX’s position during claim construction of the ‘622 and ‘291 

Patents in other litigation, during which CIVIX had argued that there were differences between the 

two terms. (Id.¶¶ 100-04.) CoStar alleges that CIVIX had the specific intent to deceive the PTO 

when it submitted Semple’s declaration contradicting CIVIX’s litigation position, and failed to 

disclose the inconsistency. (Id. ¶ 105.)

II. Alleged Inequitable Conduct in Prosecution of ‘335 Patent

The ‘335 Patent is a continuation of the ‘291 Patent. (Id. ¶ 107.) CoStar alleges that the 

‘335 Patent is “not sufficiently distinct” from the ‘291 Patent to avoid unenforceability because of 

the ‘291 Patent’s unenforceability. (Id.) CoStar also alleges several other reasons for the ‘335 

Patent’s enforceability. First, CoStar alleges that CIVIX submitted three IDSs during prosecution 

of the ‘335 Patent that included an excessive number of documents. (Id. ¶ 109 (31-page IDS 

including 245 U.S. patents, 63 foreign documents, and 270 non-patent documents); id. ¶ 112 (IDS 

listing 36 U.S. patents and 109 non-patent documents); id. ¶ 113 (50-page IDS listing more than 

580 U.S. patents and non-patent documents). In response, the patent examiner asked CIVIX to 

identify relevant references and highlight relevant sections within those references. (Id. ¶¶ 110-11, 

114.) CIVIX attempted to comply by designating 120 documents that “may be relevant with 

respect to advertising,” but the examiner found that designation insufficient. (Id. ¶¶ 115-17.) 

CIVIX then submitted a declaration by Semple identifying just 34 of the disclosed 

references. (Id. ¶ 118.) CoStar alleges that the list of 34 references failed to identify other 

references from the IDSs that were relevant to the asserted claims of the ‘335 Patent, which relates 

to “advertising over the Internet.” (Id. ¶¶ 119, 126.)5 In addition, the 34 references were allegedly 

 5 The Third Amended Complaint lists, in particular, “‘A Practical Guide to Sabre 
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“cherry-picked” to include only references to the Internet that post-dated CIVIX’s purported 

conception date, so that CIVIX could “swear behind” those references if the examiner used them 

to support the obviousness of the use of the Internet. (Id. ¶ 121.)6

CoStar alleges that although CIVIX knew that the omitted references were relevant, and 

that the obviousness of the Internet was important to the examiner, CIVIX omitted the references

with an intent to deceive the PTO. (Id. ¶¶ 122-24, 127, 131.) In particular, the Third Amended 

 

Reservations and Ticketing’ (1992) by Jeanne Semer-Purzycki; ‘The Official Guide to the Prodigy 

Service’ (1991) by John L. Viescas; ‘Format Quick Reference Guide’; and the transcript of the 

‘Galileo Deposition’ and related exhibits.” (Id. ¶ 119.)

6 According to CoStar’s Third Amended Complaint, the references in the IDSs that were 

not listed by Semple in his declaration, but that refer to the Internet include

“CompuServe Extends Information Superhighway with Enhanced Internet 

Access,” (March 11, 1994) by Gary Steiner; “CompuServe Access.” (March 11, 

1994) by Berry Wheeler; “CompuServe Subscribers to Have R.C.S. Access,” 

(March 13, 1994) by Ed Jackson; “Access to CompuServe from the Internet 

Available Now,” PR Newswire (March 31, 1994); “CompuServe, Dow Plug Into 

Internet,” MacWeek, Volume 8, No. 12 (March 21, 1994) by Nathalie Welch; 

“Microfile - CompuServe’s New Services,” The Guardian, (March 24, 1994) by 

Jack Schofield).

(Id. ¶ 121.) CoStar’s Third Amended Complaint also alleges that Semple failed to identify 

references in the IDSs that “were relevant in teaching the use of the Internet-like networking 

systems generally,” including:

“A Practical Guide to Sabre Reservations and Ticketing” (1992) by Jeanne 

Semer-Purzycki; “The Official Guide to the Prodigy Service” (1991) by John L. 

Viescas; “Format Quick Reference Guide”; “Rules and Reservations - Airline 

Computer Reservation Systems”, Airline Business (August 1, 1993); “Learning 

Apollo - Basic and Advanced Training,” Delmar Publishing (1994), by Talula 

Gunter; MAPBASE User Manual, Nextbase Limited, (1992–1993); and 

“Searching Dialog: The Complete Guide,” Dialog Information Services (August 

1987).

(Id. ¶ 125.)
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Complaint alleges that CIVIX argued to the PTO that none of the cited references suggested use of 

the Internet (Id. ¶ 127), indicating that it knew of the materiality of the Internet references. 

Finally, CoStar alleges that during prosecution of the ‘335 Patent CIVIX alternately argued 

that the terms “Internet” and “internet” were similar and that they were different, depending on the 

situation. (Id. ¶¶ 132-37.)

ANALYSIS

Under the Federal Rules of Civil Procedure, a complaint need contain only “a short and 

plain statement of the claim showing that the pleader is entitled to relief.” Fed. R. Civ. P. 8(a)(2). 

The complaint must “give the defendant fair notice of what the . . . claim is and the grounds upon 

which it rests.” Bell Atl. Corp. v. Twombly, 550 U.S. 544, 555 (2007) (quoting Conley v. Gibson, 

355 U.S. 41, 47 (1957)). Although “detailed factual allegations” are not required, “labels and 

conclusions, and a formulaic recitation of the elements of a cause of action will not do.” Id. The 

complaint must “contain sufficient factual matter, accepted as true, to ‘state a claim to relief that is 

plausible on its face.’” Ashcroft v. Iqbal, 556 U.S. 662, 678 (2009) (quoting Twombly, 550 U.S. at 

570). “A claim has facial plausibility when the plaintiff pleads factual content that allows the court 

to draw the reasonable inference that the defendant is liable for the misconduct alleged.” Id.

Establishing a claim of inequitable conduct requires a party to show “that information 

material to patentability was withheld from the PTO, or material misinformation was provided to 

the PTO, with the intent to deceive or mislead the patent examiner into granting the patent.” 

Outside the Box Innovations, LLC v. Travel Caddy, Inc., 695 F.3d 1285, 1290 (Fed. Cir. 2012). 

The Federal Circuit en banc recently clarified, contrary to prior law, that “the materiality required 

to establish inequitable conduct is but-for materiality,” meaning that the PTO would not have 
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allowed a claim if it had been aware of the withheld information. Therasense, Inc. v. Becton, 

Dickinson & Co., 649 F.3d 1276, 1291 (Fed. Cir. 2011) (en banc). For example, “[w]hen an 

applicant fails to disclose prior art to the PTO, that prior art is but-for material if the PTO would 

not have allowed a claim had it been aware of the undisclosed prior art.” Id. The party asserting 

inequitable conduct must show that the patentee possessed the relevant conditions of mind, 

including “(1) knowledge of the withheld material information or of the falsity of the material 

misrepresentation, and (2) specific intent to deceive the PTO.” Exergen Corp. v. Wal-Mart Stores, 

Inc., 575 F.3d 1312, 1327 (Fed. Cir. 2009).

It has long been the law that to plead a claim for inequitable conduct, a plaintiff’s

allegations must comport with Rule 9(b), which “requires that the pleadings contain explicit rather 

than implied expression of the circumstances constituting fraud.” Id. (quoting King Auto., Inc. v. 

Speedy Muffler King, Inc., 667 F.2d 1008, 1010 (C.C.P.A. 1981)). In particular, the Federal Circuit 

has held that “Rule 9(b) requires identification of the specific who, what, when, where, and how of 

the material misrepresentation or omission” to the PTO. Id. Rule 9(b) allows “[m]alice, intent, 

knowledge, and other conditions of a person’s mind” to be alleged generally, Fed. R. Civ. P. 9(b),

but the pleadings must “allege sufficient underlying facts from which a court may reasonably infer 

that a party acted with the requisite state of mind.” Exergen, 575 F.3d at 1327.

I. ‘622 and ‘291 Patents

CoStar alleges that the ‘622 and ‘291 Patents are unenforceable due to inequitable conduct 

because of four of CIVIX’s actions during prosecution and reexamination of those patents: (1) 

CIVIX’s failure to disclose prior parent patent lawsuits involving the subject matter of the ‘622 

and ‘291 Patents; (2) CIVIX’s failure to disclose Bouve’s failing health when it submitted the 
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Bouve Declaration; (3) CIVIX’s representations to the PTO that the terms “Internet” and 

“internet” were identical, contrary to arguments in previous litigation; and (4) CIVIX’s “burying”

of relevant references. The court will address each of the alleged actions in turn.

A. Prior Parent Patent Lawsuits

The court will first consider whether CoStar’s allegations regarding CIVIX’s failure to 

disclose the lawsuits involving the ‘525 Patent are sufficient to state a claim for inequitable 

conduct in the prosecution of the ‘622 and ‘291 Patents. The Manual of Patent Examining 

Procedure (“MPEP”) provides that parties must disclose prior litigation involving the subject 

matter of a patent application:

Where the subject matter for which a patent is being sought is or has been involved 

in litigation, the existence of such litigation and any other material information 

arising therefrom must be brought to the attention of the U.S. Patent and Trademark 

Office. Examples of such material information include evidence of possible prior 

public use or sales, questions of inventorship, prior art, allegations of “fraud,” 

“inequitable conduct,” and “violation of duty of disclosure.”

MPEP § 2001.06(c) (8th ed. rev. 2012). 

The courts are “not bound by the definition of materiality in PTO rules.” Therasense, 649 

F.3d at 1294. Nevertheless, prior to the Federal Circuit’s decision in Therasense, courts generally 

assumed that litigation involving the subjects listed in MPEP § 2001.06(c) was material to a 

related pending patent application. See, e.g., Critikon, Inc. v. Becton Dickinson Vascular Access, 

Inc., 120 F.3d 1253, 1258 (Fed. Cir. 1997) (“According to the Manual of Patent Examining 

Procedure, relevant litigation includes the defenses raised against validity of the patent, or charges 

of fraud or inequitable conduct in litigation, which would normally be material to the reissue 

application.”). Following Therasense, however, materiality requires that the PTO would not have 

issued the patent if it had known of the undisclosed litigation. See Therasense, 649 F.3d at 1292 
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(“Because inequitable conduct renders an entire patent (or even a patent family) unenforceable, as 

a general rule, this doctrine should only be applied in instances where the patentee’s misconduct 

resulted in the unfair benefit of receiving an unwarranted claim. After all, the patentee obtains no 

advantage from misconduct if the patent would have issued anyway.” (citation omitted)). 

CoStar contends that the Therasense standard does not apply to parent patent litigation, and 

that the nondisclosure of parent patent litigation is sufficient to constitute inequitable conduct if 

the parent patent litigation is merely relevant in some way to the patent application. (Dkt. No. 132, 

at 12.) In support, CoStar cites Outside the Box, a Federal Circuit case in which the parent patent 

litigation dealt only with infringement, and did not involve any issues related to patentability, 

enforceability, or validity. Outside the Box, 695 F.3d at 1290-91. The Federal Circuit held that 

nondisclosure of the parent patent litigation did not constitute inequitable conduct sufficient to 

make the patent unenforceable. Id. As the Federal Circuit explained, 

However, the issue was not whether the [prior] litigation was irrelevant; the issue 

was whether the existence of the [prior] litigation was material to patentability of 

the [patent-in-suit], when there was no citation of prior art, nor any pleading of 

invalidity or unpatentability in the [prior-litigation] complaint as it existed during 

pendency of the [patent-in-suit] application.

Id. at 1291. In other words, the prior litigation would not have been material even under the 

standards applicable prior to Therasense, because it did not deal with patentability, enforceability, 

or validity. The holding of Outside the Box thus did not directly address whether Therasense’s 

but-for materiality standard applies to assertions of inequitable conduct based on parent patent 

litigation. 

Outside the Box did, however, cite Therasense’s new materiality requirement during its 

discussion of the materiality of the parent patent litigation. Id. Moreover, the language in 
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Therasense is unequivocal and categorical. Therasense, 649 F.3d at 1291 (“This court holds that, 

as a general matter, the materiality required to establish inequitable conduct is but-for 

materiality.” (emphasis added)). CoStar presents no argument to overcome these considerations, 

so the court will apply Therasense’s materiality standard to CoStar’s allegations of inequitable 

conduct based on parent patent litigation.

At the pleading stage, Twombly establishes that pleading legal conclusions is insufficient. 

Twombly, 550 U.S. at 555. To sufficiently plead but-for materiality under Therasense, therefore, 

“the accused infringer must identify some fact that would make it plausible that the PTO would not 

have granted the patent but-for the misrepresentation.” Human Genome Sciences, Inc. v. 

Genentech, Inc., No. 11-CV-6519, 2011 WL 7461786, at *4 (C.D. Cal. Dec. 9, 2011); accord SAP 

Am., Inc. v. Purple Leaf, LLC, No. C 11-4601, 2012 WL 2237995, at *6 (N.D. Cal. June 15, 2012)

(“[I]t is not enough to simply allege—as a legal conclusion—that the information was 

material—rather, there must be facts alleged supporting that element.”). 

Here, CoStar fails to meet that requirement. With respect to materiality, CoStar’s Third 

Amended Complaint alleges that “[t]he district court [in the Microsoft litigation] construed terms 

in the ‘525 Patent that are also present in the ‘622 and ‘291 Patents.” (CoStar’s Third Am. Compl. 

¶ 73.) CoStar’s Third Amended Complaint includes no explanation, however, of which terms in 

the ‘525 Patent the court construed, or of how the court’s construction of those terms relates to the 

PTO’s decision to issue the ‘622 and ‘291 Patents. That omission is fatal in light of Exergen’s 

requirement that the pleadings “explain both ‘why’ the withheld information is material 

and . . . ‘how’ an examiner would have used this information in assessing the patentability of the 

claims.” Exergen, 575 F.3d at 1329-30.
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CoStar’s Third Amended Complaint also alleges that CIVIX failed to disclose to the PTO 

the three prior art references Microsoft relied on in its November 5, 1999, motion for summary 

judgment of invalidity. (CoStar’s Third Am. Compl. ¶ 78.) With respect to materiality, CoStar 

alleges only that Microsoft alleged those references “invalidated various claim [sic] of the ‘525 

Patent.” (Id.) Again, that allegation lacks the specificity necessary under Rule 9(b) and Exergen to 

explain how the undisclosed information is material. The allegation that an interested litigant said 

so is not sufficient, as interested litigants frequently take positions that have no substantive merit.

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CoStar’s Third Amended Complaint provides no detail about which claims are allegedly 

invalidated, why they would be invalidated by Microsoft’s references, and how the PTO would 

have used the information to assess the patentability of the ‘291 or ‘622 Patents. With no other 

allegations regarding materiality, CoStar’s allegations about CIVIX’s failure to disclose the parent 

patent lawsuits are inadequate to state a claim for inequitable conduct.

B. Bouve Declaration

CoStar’s allegations regarding the Bouve Declaration are similarly inadequate to state a 

claim for inequitable conduct in the prosecution of the ‘622 and ‘291 Patents. Once again, CIVIX 

contends that CoStar’s allegations fail to establish but-for materiality under the Therasense

standard, because CoStar, aside from mere conclusory allegations, has “failed to plead facts 

sufficient to show that the PTO would not have granted” the patents if the PTO had been aware of 

Bouve’s health problems. (Dkt. No. 110, at 10.) 

 7 Microsoft’s summary judgment of invalidity motion was mooted when the court granted 

Microsoft summary judgment of non-infringement, so the Colorado court never expressed an 

opinion on the merits of Microsoft’s invalidity argument. See Dkt. No. 295, CIVIX-DDI, LLC v. 

Microsoft Corp., No. 99-cv-172 (D. Colo. Feb. 23, 2000).
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The court agrees. CoStar merely alleges that Bouve’s health problems were material 

“because a reasonable examiner would consider it important” in deciding whether to issue the 

patents. (CoStar’s Third Am. Compl. ¶ 95.) But that allegation merely states a conclusion of law, 

and the wrong conclusion of law at that, now that the Federal Circuit requires but-for materiality. 

Even aside from the lack of allegations showing materiality, the court’s “judicial 

experience and common sense,” Iqbal, 556 U.S. at 679, suggest that CoStar’s allegations of 

materiality are implausible. The Bouve Declaration, which deals with events surrounding the 

invention of the patented methods, was signed by both Bouve and Semple, two of the inventors. 

Even if Bouve’s credibility were discounted because of his strokes and memory problems, 

Semple’s credibility would still support the contents of the Bouve Declaration. It is thus 

implausible to believe that the PTO would have discounted the contents of the Bouve Declaration 

if it had known of Bouve’s health problems. CoStar’s allegations related to the Bouve Declaration

are inadequate to state a claim for inequitable conduct.

C. Distinction Between “Internet” and “internet”

Next the court addresses CoStar’s allegations related to Semple’s declaration during the 

reexamination of the ‘622 and ‘291 Patents that the terms “Internet” and “internet” had the same 

meaning at the time of the invention. (CoStar’s Third Am. Compl. ¶¶ 98-99.) CoStar alleges that 

CIVIX failed to disclose that this declaration was inconsistent with CIVIX’s position in previous 

litigation involving the ‘622 and ‘291 Patents. (Id. ¶¶ 100-04.) Once again, CoStar has failed 

sufficiently to plead the materiality of CIVIX’s alleged omission under Therasense. 

Prior to Therasense, the general rule was that “‘any assertion that is made by a 

litigant . . . during litigation, which is contradictory to the assertions made . . . to the patent 
15

examiner, comprises material information.’” Environ Prods., Inc. v. Total Containment, Inc., No. 

CIV.A. 95-4467, 1997 WL 364464, at *4 (E.D. Pa. June 19, 1997) (quoting Golden Valley 

Microwave Foods, Inc. v. Weaver Popcorn Co., 837 F. Supp. 1444, 1477 (N.D. Ind. 1992), aff’d, 

11 F.3d 1072 (Fed. Cir. 1993)); see also MPEP § 2001.06(c) (“Another example of such material 

information is any assertion that is made during litigation which is contradictory to assertions 

made to the examiner.”). Moreover, PTO regulations explicitly require the disclosure of any 

non-cumulative information that “refutes, or is inconsistent with, a position the applicant takes” 

before the PTO regarding patentability. 37 C.F.R. § 1.56 (2013) (“Rule 56”). The Federal Circuit 

in Therasense, however, explicitly refused to adopt the materiality standard of Rule 56, stating that 

it is “overly broad because information is considered material even if the information would be 

rendered irrelevant in light of subsequent argument or explanation by the patentee.” Therasense, 

649 F.3d at 1294. Once again, therefore, the but-for materiality standard of Therasense applies, 

and CoStar must allege facts sufficient to suggest that the PTO would not have issued the ‘622 and 

‘291 Patents if CIVIX had disclosed the inconsistency in its arguments. 

CoStar alleges, with respect to the materiality of the inconsistency, that

CIVIX knew that Mr. Semple’s Internet declaration was material to the USPTO 

because it was submitted after its claims had been rejected for invalidity in view of 

prior art that disclosed “Internet” references. Moreover, CIVIX’s litigation position 

was material to the USPTO’s determination of patentability because a reasonable 

patent examiner would consider it important in deciding whether to allow the 

claims to survive reexamination because of the obvious inconsistency.

(CoStar’s Third Am. Compl. ¶ 104.) The second sentence of that allegation merely states a legal 

conclusion (and again, after Therasense, a conclusion inadequate to establish inequitable conduct).

The first sentence is somewhat more substantive, but again is inadequate to allege but-for 

materiality. Paragraph 104 states that at least some of the claims of the ‘622 and ‘291 Patents (it 
16

does not state which claims) were rejected for invalidity because of prior art that disclosed 

“Internet references.” It is not clear how these unidentified “Internet” references are relevant to the 

claims of the ‘622 or ‘291 Patents, particularly because the patents do not claim the “Internet” in 

the abstract. Instead, they claim methods for using the Internet to connect a user to a database from 

a remote location and to retrieve information about items of interest in a particular geographic 

vicinity. The Third Amended Complaint does not explain how the “‘Internet references” in ¶ 104 

invalidated any of the proposed claims of the ‘622 or ‘291 Patents, or whether the invalidation 

related to the distinction, or lack thereof, between “Internet” and “internet” that Semple’s 

Declaration addressed.

Moreover, CoStar’s allegations of materiality are not only inadequate, but also 

implausible. All of the references to the “Internet” in the claims of the ‘622 and ‘291 Patents are 

capitalized. See CIVIX-DDI, LLC v. Cellco P’ship, No. 03 C 2792, 2005 WL 831307, at *2 (N.D. 

Ill. Apr. 6, 2005) (“The term ‘Internet’ appears in claims 6, 12, 20, 23, 26, 29, 38, 61, and 63 of the 

‘622 patent, and claims 1 and 14 of the ‘291 patent. The term “internet” appears in claim 6 of the 

‘307 patent.”). Semple’s declaration supporting the view that “Internet” and “internet” are 

interchangeable would thus serve to expand the universe of prior art references that could 

potentially invalidate the ‘622 and ‘291 Patents. That is, if “Internet” is equivalent to “internet,” 

then any reference referring to either “Internet” or “internet” could potentially invalidate the 

patents. By contrast, if there is a distinction between the terms, only references to “Internet” have 

that potential.

Semple’s declaration thus actually broadens the scope of the Patents, which might assist 

CIVIX in future infringement lawsuits, but hinders it during reexamination before the PTO, when 
17

validity is at issue. Far from being but-for material, therefore, CIVIX’s prior contrary position in 

litigation actually would have weighed in favor of patentability, not against it. It is thus 

implausible to allege that the PTO would have denied reissuing the ‘622 and ‘291 Patents if it had 

known of CIVIX’s prior position.8

D. Burying References 

CoStar alleges that the ‘291 Patent is unenforceable because of CIVIX’s submissions to the 

PTO that buried the most relevant references. (CoStar’s Third Am. Compl. ¶¶ 85-87.) CoStar also 

alleges that CIVIX’s disclosures with respect to the ‘622 Patent were inadequate because CIVIX 

did not submit an IDS with respect to that patent. (Id. ¶ 86.) The allegations relating to the IDSs 

accompanying the ‘622 and ‘291 patent applications are only three paragraphs long (Id. ¶¶ 85-87), 

and do not include any allegations regarding the materiality of CIVIX’s allegedly inadequate 

disclosures. Those allegations are thus inadequate under Exergen and Therasense.

II. ‘335 Patent

CoStar alleges that the ‘335 Patent is unenforceable due to inequitable conduct for three 

reasons: (1) it is a continuation of the ‘291 Patent, and its claims are not sufficiently distinct from 

the claims of the ‘291 Patent to avoid being tainted by the inequitable conduct; (2) CIVIX’s 

submissions to the PTO buried references most relevant to the alleged obviousness of the ‘335 

Patent, and CIVIX failed, upon request of the PTO, to specify the most relevant references

(CoStar’s Third Am. Compl. ¶¶ 108-131); and (3) CIVIX alternatively argued to the PTO that 

“internet” and “Internet” had the same meaning, and that they had different meanings, depending 

 8 CoStar’s allegations that Semple submitted his declaration to deceive the PTO regarding 

the patentability of the ‘622 and ‘291 Patents (CoStar’s Third Am. Compl. ¶ 105) are also 

implausible. The submission of his declaration likely hurt CIVIX’s case for patentability, rather 

than helping it.
18

on “whatever position it needs to take at that time” (CoStar’s Third Am. Compl. ¶ 136). In light of 

the court’s dismissal of CoStar’s allegations that the ‘291 Patent is unenforceable, the first reason 

is without merit. The court addresses the other two reasons below.

A. Burying References and Failing to Identify which References are Most Relevant

CoStar alleges that CIVIX, through the named inventors and prosecuting attorneys of the 

‘335 Patent, submitted an excessive number of documents as part of its IDSs for the ‘335 Patent.

(Id. ¶ 109 (31-page IDS including 245 U.S. patents, 63 foreign documents, and 270 non-patent 

documents); id. ¶ 112 (IDS listing 36 U.S. patents and 109 non-patent documents); id. ¶ 113 

(50-page IDS listing more than 580 U.S. patents and non-patent documents). When the PTO 

specifically requested that CIVIX identify the most relevant references, CIVIX ultimately 

submitted a declaration by Semple identifying just 34 of the disclosed references. (Id. ¶ 118.) 

CoStar’s allegations then identify specific disclosed references that were allegedly omitted from 

Semple’s declaration. (Id. ¶¶ 121, 125.) 

CoStar also alleges facts showing a plausible theory for how these omitted references were 

but-for material. Specifically, CoStar alleges that the omitted references disclose the use of the 

Internet or “internet-like networking systems generally” to communicate between a user and a 

remote database from which the user seeks information. (Id.) CoStar then alleges that if the PTO 

had focused on these references, it would have declined to issue claim 1 of the ‘335 Patent, and all 

of the claims dependent on it, on the ground of obviousness. (Id. ¶¶ 122-23, 126.) Finally, CoStar 

alleges that CIVIX knew of the materiality of the omitted references and intended to deceive the 

PTO by burying, and then upon request failing to highlight, those references. To show CIVIX’s 

knowledge and intent, CoStar alleges that CIVIX argued to the PTO that none of its references 
19

taught or suggested the use of the Internet in this context, and that the ‘335 Patent was thus 

non-obvious. (Id. ¶¶ 127-28.)

CIVIX contends that although CoStar’s allegations list the references allegedly omitted 

from Semple’s declaration, they specifically “fail[] to identify which claims, and which limitations 

in those claims, the withheld references are relevant to, and where in those references the material 

information is found.” Exergen, 575 F.3d at 1329. But CoStar specifically alleges that the 

references are relevant “to all the asserted claims of the ‘335 Patent, as claim 1, the only 

independent claim, pertains to ‘advertising over the Internet’, and all other claims of the ‘335 

Patent are dependent on claim 1.” (CoStar’s Third Am. Compl. ¶ 126.) That allegation adequately 

identifies the claims the withheld references are relevant to. 

With respect to identifying where in the references the relevant information is found, 

CoStar does not identify page numbers to specifically pinpoint the relevant information in the 

withheld references. CoStar’s allegations do, however, describe what information in the references 

is relevant. (See id. ¶ 125 (stating that the withheld references “disclose the use of CompuServe on 

the Internet” and “were relevant in teaching the use of the Internet-like networking systems 

generally”); see also id. ¶ 121.) Although a party alleging inequitable conduct would be well 

advised to include page numbers, doing so is not absolutely necessary to meet Exergen’s 

requirements if the pleading adequately describes the relevant information. Indeed, if the relevant 

information is adequately described, filling in the page and line numbers is merely an academic, 

redundant exercise. This court will not require such technical pleading. 

Here, CoStar’s descriptions of the relevant information in the withheld references are 

somewhat vague, but the court believes that they are adequate at the pleading stage to put CIVIX 
20

on notice of the claims against it. In the context of the patents-in-suit, CoStar’s descriptions plainly 

indicate that the relevant information in the withheld references is how to use the Internet to 

communicate between a user and a remote database from which the user seeks information.

CoStar’s allegations are thus adequate to pinpoint the “what” and “where” of the material 

omissions. See Exergen, 575 F.3d at 1329.

CIVIX next argues that CoStar’s allegations are insufficient because CoStar has failed to 

establish that an intent to deceive the PTO is the “single most reasonable inference” to be drawn 

from the alleged facts. Therasense, 649 F.3d at 1290 (quoting Star Scientific, Inc. v. R.J. Reynolds 

Tobacco Co., 537 F.3d 1357, 1366 (Fed. Cir. 2008)). As Therasense makes plain, however, the 

requirement that the intent to deceive be the single most reasonable inference stems from the 

requirement at the merits stage that the proponent of inequitable conduct prove its case by clear 

and convincing evidence. See id. (“[T]o meet the clear and convincing evidence standard, the 

specific intent to deceive must be ‘the single most reasonable inference able to be drawn from the 

evidence.’” (quoting Star Scientific, 537 F.3d at 1366)). At the pleading stage, by contrast, the 

proponent of inequitable conduct need only plead sufficient facts that the court “may reasonably 

infer” knowledge and intent. Exergen, 575 F.3d at 1328-29 & n.5. CoStar’s allegations meet that 

standard, insofar as they identify a plausible motive and opportunity for hiding the relevant 

references from the PTO.

Next, CIVIX contends that as a matter of law, “burying” references cannot constitute 

inequitable conduct. In support, it cites the Federal Circuit’s comment that “[w]hen a reference 

was before the examiner, whether through the examiner’s search or the applicant’s disclosure, it 

can not [sic] be deemed to have been withheld from the examiner.” Scripps Clinic & Research 
21

Found. v. Genentech, Inc., 927 F.2d 1565, 1582 (Fed. Cir. 1991), overruled on other grounds by

Abbott Labs. v. Sandoz, Inc., 566 F.3d 1282 (Fed. Cir. 2009); accord Fiskars, Inc. v. Hunt Mfg. 

Co., 221 F.3d 1318, 1327 (Fed. Cir. 2000); Litton Sys., Inc. v. Honeywell, Inc., 87 F.3d 1559, 1571 

(Fed. Cir. 1996), vacated on other grounds, 520 U.S. 1111 (1997), aff’d in part, rev’d in part, 

vacated in part, and remanded, 140 F.3d 1449 (Fed. Cir. 1998), abrogated by Festo Corp. v. 

Shoketsu Kinzoku Kogyo Kabushiki Co., 234 F.3d 558 (Fed. Cir. 2000).

As a recent law review article explains, however,

The Scripps, Litton, and Fiskars Federal Circuit decisions do not necessarily 

preclude burying from being a form of inequitable conduct as they did not address 

the burying issue directly. In Scripps, the reference had not been disclosed and 

instead was discovered by the patent examiner “on his own.” In Litton, the patent 

applicant originally withheld the reference but later disclosed it during reissue. In 

Fiskars, the applicant disclosed a brochure describing what he considered to be the 

closest prior art to his invention, but the examiner indicated that the brochure had 

not been considered. The Federal Circuit consequently found no inequitable 

conduct because the brochure was before the examiner. None of these decisions 

speak directly to burying, and none necessarily preclude the practice from being a 

form of inequitable conduct.

Robert Brendan Taylor, Burying, 19 Mich. Telecomm. & Tech. L. Rev. 99, 107-08 (2012)

(footnotes omitted). Accordingly, the Federal Circuit has not established definitively whether or 

under what circumstances burying may constitute inequitable conduct. 

The court need not address that question directly in this case, because the alleged conduct 

extends beyond merely burying the relevant references. CoStar also alleges that CIVIX omitted 

material references in response to the PTO’s specific request for assistance in identifying relevant 

references from the material in CIVIX’s IDSs. Accepting these allegations as true, by deliberately 

focusing the PTO’s attention on the references it identified, CIVIX successfully avoided scrutiny 

of other references that allegedly would have rendered its invention unpatentable. That behavior is 
22

more culpable than merely submitting a large volume of references, as in a typical “burying” 

allegation. Moreover, CIVIX’s alleged conduct directly violates its duty of candor to the PTO. In 

effect, CIVIX’s response to the PTO’s request is an affirmative misrepresentation that the 

identified references are more relevant than the disclosed, but not identified, references.

Allegations of such behavior are adequate to state a claim for inequitable conduct.

B. Contradictory Argument on Meaning of “Internet” and “internet”

CoStar’s allegations that CIVIX’s attorneys took whatever position was most favorable at 

the time with respect to the meanings of “internet” and “Internet” are insufficient to allege a claim 

for inequitable conduct because “an applicant is free to advocate its interpretation of its claims and 

the teachings of prior art.” Innogenetics, N.V. v. Abbott Labs., 512 F.3d 1363, 1379 (Fed. Cir. 

2008). 

CoStar is correct that “[c]ases involving affidavits or declarations are held to a higher 

standard,” and that the submission of false affidavits can thus constitute inequitable conduct. Id.

Moreover, CoStar alleges that CIVIX submitted affidavits to “sw[ear] behind various ‘Internet’ 

references” during prosecution of the ‘335 Patent. (CoStar’s Third Am. Compl. ¶ 135.) CoStar 

does not allege, however, that those affidavits directly took a position on the meaning of the term 

“Internet,” instead merely alleging that they were inadequate to establish an earlier priority date.

(Id. (“But those documents do not establish that CIVIX’s early conception date involved the use of 

TCP/IP or the worldwide scope of the ‘Internet,’ as opposed to a more generic ‘internet’

network.”).) Accordingly, CoStar has not adequately alleged that CIVIX submitted false 

affidavits, and it has thus failed to state a claim for inequitable conduct with respect to CIVIX’s 

arguments about the meanings of “Internet” and “internet.” 
23

CONCLUSION

For the reasons explained above, CIVIX’s motion to dismiss CoStar’s inequitable conduct 

claims (Dkt. No. 109) is granted in part and denied in part. CoStar’s claims in its Third Amended 

Complaint (Dkt. No. 99) that the ‘622 and ‘291 Patents are unenforceable because of inequitable 

conduct are dismissed, as is CoStar’s claim that the ‘335 Patent is unenforceable due to inequitable 

conduct in the prosecution of the ‘291 Patent. CoStar’s claim that the ‘335 Patent is unenforceable 

because of inequitable conduct in the prosecution of the ‘335 Patent shall stand, but paragraphs 

132 through 137 of CoStar’s Third Amended Complaint (Dkt. No. 99) are dismissed, as they fail to 

state a claim that CIVIX’s alternative arguments on the meanings of “Internet and “internet” 

constitute inequitable conduct.

CIVIX’s motion to dismiss LoopNet’s inequitable conduct claim and its Sixth Affirmative 

Defense (Dkt. No. 112) is also granted in part and denied in part. LoopNet’s claim that the ‘335 

Patent is unenforceable due to inequitable conduct in the prosecution of the ‘291 Patent is 

dismissed. LoopNet’s claim that the ‘335 Patent is unenforceable because of inequitable conduct 

in the prosecution of the ‘335 Patent shall stand, but paragraphs 56 through 61 of LoopNet’s 

Second Amended Answer and Counterlcaims (12-8632, Dkt. No. 71) are dismissed, as they fail to 

state a claim that CIVIX’s alternative arguments on the meanings of “Internet and “internet” 

constitute inequitable conduct. The dates set in Dkt. Nos. 83 and 131 shall remain in effect. 

ENTER:

_______________________________

JAMES F. HOLDERMAN

Chief Judge, United States District Court

Date: May 15, 2013