IN THE UNITED STATES DISTRICT COURT 

FOR THE WESTERN DISTRICT OF TEXAS 

WACO DIVISION 

WSOU INVESTMENTS, LLC d/b/a 

BRAZOS LICENSING AND 

DEVELOPMENT, 

Plaintiff, 

v. 

DELL TECHNOLOGIES INC., DELL 

INC., EMC CORPORATION, AND 

VMWARE, INC., 

Defendant.

Case No.: 6:20-cv-00485-ADA 

JURY TRIAL DEMANDED 

PLAINTIFF’S OPPOSITION TO DEFENDANTS’ MOTION 

FOR LEAVE TO AMEND INVALIDITY CONTENTIONS 

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TABLE OF CONTENTS 

TABLE OF AUTHORITIES ......................................................................................................... iii

TABLE OF ABBREVIATIONS ................................................................................................... iv

I. INTRODUCTION .................................................................................................................. 1

II. LEGAL STANDARD ............................................................................................................. 2

III. ARGUMENT ...................................................................................................................... 2

A. Defendants Were Not Diligent............................................................................................ 2

B. The Three New References Are Not Essential to Defendants’ Case .................................. 6

C. WSOU Would Be Unfairly Prejudiced by the Proposed Amendments .............................. 7

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TABLE OF AUTHORITIES 

CASES

Computer Acceleration Corp. v. Microsoft Corp., 

481 F. Supp. 2d 620, 625 (E.D. Tex. 2007) ................................................................................ 4 

Cummins-Allison Corp. v. SBM Co., Ltd., 

No. CIV.A. 9:07-CV-196, 2009 WL 763926 (E.D. Tex. Mar. 19, 2009) ............................... 2, 7 

Innovative Display Techs. v. Acer Inc., 

No. 2:13-cv-522-JRG, 2014 WL 2796555 (E.D. Tex. Jun. 19, 2014) ........................................ 2 

Invensys Sys., Inc. v. Emerson Elec. Co., 

No. 6:12-cv-799-LED, 2014 WL 12598865 (E.D. Tex. Dec. 3, 2014) ...................................... 3 

MacroSolve, Inc. v. Antenna Software, Inc., 

No. 6:11-CV-287-MHS-JDL, 2013 WL 3833079 (E.D. Tex. July 23, 2013) ............................ 7 

Maxell Ltd. v. Apple Inc., 

No. 5:19-CV-00036-RWS, 2020 WL 10456917 (E.D. Tex. Feb. 24, 2020) .............................. 6 

O2 Micro Int'l Ltd. v. Monolithic Power Sys., Inc., 

467 F.3d 1355 (Fed. Cir. 2006) ................................................................................................... 2 

Ohio Willow Wood Co. v. Thermo-Ply, Inc., 

No. 9:07-CV-274, 2009 WL 10677580 (E.D. Tex. June 10, 2009) ........................................ 4, 6 

S & W Enters., L.L.C. v. Southtrust Bank of Ala., NA, 

315 F.3d 533 (5th Cir. 2003) ....................................................................................................... 2 

Seven Networks, LLC v. Google, LLC, 

No. 2:17-cv-442, Dkt. 198, slip copy (E.D. Tex. June 8, 2018) ................................................. 7 

Sightsound Tech., LLC v. Apple, Inc., 

No. 11-1292, 2013 WL 1500617 (W.D. Pa. Apr. 11, 2013) ................................................... 3, 4 

Uniloc 2017 LLC v. Google LLC, 

No. 2:18-CV-00493-JRG-RSP, 2019 WL 6465318 (E.D. Tex. Dec. 2, 2019) ........................... 6 

STATUTES

Fed. R. Civ. P. 16(b) ....................................................................................................................... 1 

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TABLE OF ABBREVIATIONS 

Abbreviation Meaning 

Brazos WSOU Investments, LLC d/b/a Brazos Licensing and Development 

Defendants Dell Technologies Inc., Dell Inc., EMC Corporation, and VMware, 

Inc., collectively 

’309 patent U.S. Patent No. 7,636,309 

Bertsekas Bertsekas, Dimitri et al., Data Networks, Prentice Hall, New Jersey, 

Second Edition (1992) 

Fodor Fodor, Gabor et al., Path Optimization for Elastic Traffic Under 

Fairness Constraints, Teletraffic Engineering in the Internet Era 

(Proceedings of ITC), Teletraffic Science and Engineering, vol. 4 

(2001) 

Krishnan Krishnan, Ram et al., An Approach to Path-Splitting in Multipath 

Networks, CENG Technical Report 92-10, Department of Electrical 

Engineering – Systems, University of Southern California, Los 

Angeles (August 1992) 

USPTO United States Patent and Trademark Office 

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I. INTRODUCTION 

The Court should deny Defendants’ motion for leave to amend their Invalidity Contentions 

for the ’309 patent (Dkt. 160; “Motion”) because Defendants cannot show diligence either in 

discovering the three newly alleged prior art references months after Defendants provided their 

Final Invalidity Contentions or in disclosing them to Brazos in this litigation several months later. 

Defendants are not seeking to add some newly discovered, obscure references that were difficult 

to locate or only accessible through third parties. Rather, the three new references Defendants 

seek to add were all publicly accessible, were indexed on public search engines, and include a 

textbook published in 1987 (Bertsekas); a paper in the journal Teletraffic Science and Engineering 

published in 2001 (Fodor); and a 1992 CENG Technical Reports paper that is downloadable from 

the University of Southern California engineering website (Krishnan). Indeed, far from being 

difficult to identify, Bertsekas was cited in numerous other references that Defendants already 

relied upon in their Final Invalidity Contentions in June 2021. 

Even to the extent Defendants’ representation is true that they did not first discover these 

new references until September or October 2021, that was about 6 months ago and Defendants 

admittedly concealed these references for months before first disclosing them to Brazos and even 

longer before seeking to amend their invalidity contentions. All the while, Defendants were 

covertly planning to rely on these references to support their invalidity case, as evidenced by the 

reexamination request they submitted to the USPTO on December 17, 2021. Defendants have no 

justifiable excuse for not identifying or disclosing these additional references significantly earlier 

than they did. Given Defendants’ concealment and lack of diligence, the Court should deny their 

Motion for failing to show good cause. 

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II. LEGAL STANDARD 

A party seeking to modify the Court’s Docket Control order must show “good cause.” See

Fed. R. Civ. P. 16(b). A party may amend its invalidity contentions only by order of the Court 

upon a showing of good cause, which, according to the Federal Circuit, “requires a showing of 

diligence.” O2 Micro Int'l Ltd. v. Monolithic Power Sys., Inc., 467 F.3d 1355, 1366 (Fed. Cir. 

2006). “The burden is on the movant to establish diligence rather than on the opposing party to 

establish a lack of diligence.” Id. An exercise of diligence requires both diligence in discovering

the prior art and diligence in promptly bringing new arts to the attention of the Plaintiff and the 

Court. Innovative Display Techs. v. Acer Inc., No. 2:13-cv-522-JRG, 2014 WL 2796555, at *1-2 

(E.D. Tex. Jun. 19, 2014). 

While a Court has broad discretion to grant untimely motions to amend pleadings, it should 

consider four factors in ruling on such motions: (1) the explanation for the failure to meet the 

deadline, including whether it was within the reasonable control of the movant; (2) the importance 

of the thing that would be excluded; (3) the potential prejudice in allowing the thing that would be 

excluded; and (4) the available of a continuance to cure such prejudice. S & W Enters., L.L.C. v. 

Southtrust Bank of Ala., NA, 315 F.3d 533, 536 (5th Cir. 2003); Cummins-Allison Corp. v. SBM 

Co., Ltd., 2009 WL 763926, at *2 (E.D. Tex. Mar. 19, 2009). As discussed below, these factors 

weigh against granting Defendants’ motion for leave to amend their Invalidity Contentions. 

III. ARGUMENT 

A. Defendants Were Not Diligent in Discovering or Disclosing the References 

Defendants have not met their burden of establishing they were diligent either in searching 

for and identifying the new prior art references, or in disclosing the references to Brazos once they 

were discovered. Because Defendants fail to meet this burden, the Court should deny Defendants 

leave to amend their invalidity contentions. 

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In making diligence determinations, courts have looked to a party’s diligence in 

discovering the references. More particularly, it is not enough that a defendant “acted promptly in 

bringing [] new arts to the attention of the Plaintiff and the Court.” Innovative Display, 2014 WL 

2796555, at *1 . Rather, a defendant must “explain why, with reasonable diligence, they could not 

have discovered such arts prior to the deadline for filing Invalidity Contentions.” Id. More 

particularly, “the critical issue is whether or not [the party seeking to amend] exercised diligence 

in discovering the prior art.” Invensys Sys., Inc. v. Emerson Elec. Co., No. 6:12-cv-799-LED, 2014 

WL 12598865, at *3 (E.D. Tex. Dec. 3, 2014) (emphasis added) (internal citations omitted). 

Nothing prevented Defendants from discovering the three new references prior to the June 

2021 Final Invalidity Contentions deadline. Each of the three references is publicly available and 

indexed on public search engines. These are not prior art references that Defendants were only 

able to locate, for example, in the basement at some third-party private company. See, e.g., 

Sightsound Tech., LLC v. Apple, Inc., No. 11-1292, 2013 WL 1500617, at *2-3 (W.D. Pa. Apr. 11, 

2013) (granting in part Plaintiff’s Motion to Strike Untimely References to Prior Art where 

defendant failed to explain why it should not have known of publicly available prior art). In fact, 

the Bertsekas reference was cited in multiple references that Defendants included in their earlier 

contentions. See, e.g., Whitehill Ex. 1 (Lee) at VMW_DELL-WSOU-PA-000657 (Reference #1); 

Whitehill Ex. 2 (Zhang) at VMW_DELL-WSOU-PA-000486 (Reference #4); Whitehill Ex. 3 

(Zhao) at VMW_DELL-WSOU-PA-002241 (Reference #11); see also Dkt. 160-3 (Defendants’ 

Ex. C: 6/2/21 Final Invalidity Contentions) at 39, 41 (relying upon each of the foregoing references 

in connection with the ’309 patent).1

1

 Citations herein to “Whitehill Ex. _” refer to the corresponding exhibits to the accompanying 

Declaration of Joshua A. Whitehill. 

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Defendants’ Motion fails to provide any reasonable explanation for why they could not 

have discovered the three prior art references earlier. The explanations offered by Defendants (i.e., 

the “mathematical nature of the claims” and the “vast number of claims WSOU asserted”) amount 

to nothing more than a complaint about the difficulty of performing a prior art search, which could 

be argued by any defendant in any patent litigation. Motion at 8. Defendants have been aware of 

Brazos’s assertion of the ’309 patent and associated claims since the beginning of the lawsuit in 

June 2020. Dkt. 1. The nature of the ‘309 patent and its claims cannot have been a surprise to 

Defendants, especially at this stage of litigation. Even if the prior art search is difficult, a “party 

cannot argue that because of its own inability and delay in understanding [patent literature], it 

possesses good cause to prepare new invalidity contentions.” Ohio Willow Wood Co. v. ThermoPly, Inc., No. 9:07-CV-274, 2009 WL 10677580 *1 (E.D. Tex. June 10, 2009). 

Regardless, any delay was within the control of Defendants and there was ample time for 

Defendants to hire prior art search firms and engage experts to search for publicly available 

publications and prior art references well before the June 25, 2021 deadline for Final Invalidity 

Contentions. See Computer Acceleration Corp. v. Microsoft Corp., 481 F. Supp. 2d 620, 625 (E.D. 

Tex. 2007) (finding that a seven-week time constraint to produce invalidity contentions did not 

weigh in favor of granting Defendant’s request to amend its invalidity contentions). 

If Defendants’ motion is granted merely because there are a purportedly large number of 

patent claims and the patent claims involve mathematical formulas, then the requirement for good 

cause and diligence would be eviscerated, creating a loophole and setting a dangerous precedent 

that would allow defendants to “peruse volumes of potential prior art at their leisure, and amend 

required disclosures at their leisure,” effectively rendering Court-ordered deadlines meaningless. 

Sightsound, 2013 WL 1500617, at *3. It would also allow defendants to amend or supplement their 

Case 6:20-cv-00485-ADA Document 173 Filed 03/30/22 Page 8 of 14
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invalidity contentions any time a hired consultant or prior art search firm finds a new reference. 

That is not the purpose of setting a deadline for “Final ... Invalidity Contentions” in the Court’s 

Scheduling Order. See Dkt. 52 at 3. Defendants’ assumption that WSOU will likely have to 

confront these references at the USPTO ignores the importance of enforcing the disclosure and 

discovery rules to ensure that outcomes are based upon the merits, and not unduly influenced by 

surprise and delay. 

Further, Defendants did not disclose these references to WSOU until six months after their 

Final Invalidity Contentions were due. Even after Defendants discovered the references, they did 

not timely disclose them to Brazos. By Defendants’ own admission, Defendants identified the 

references in September and October 2021. Motion at 4. Defendants then used these references to 

prepare their ex parte reexamination request to the USPTO, which they filed on December 17, 

2021. Dkt. 160-4 (Defendants’ Ex. D). While Defendants’ Motion is not forthcoming with details 

about when they began preparing the reexamination request, the reexamination requests includes 

declarations and exhibits that suggest that the reexamination request preparation was underway by 

no later than November 11, 2021, if not significantly earlier. See, e.g., Whitehill Ex. 4 at Exhibits 

2-A, 3-A, & 5-A (showing printout dates of November 11, 2021 for documents concerning the 

three new references). From the time Defendants purportedly discovered the new references 

through the time they filed their reexamination request with the USPTO, Defendants concealed 

their intent to rely on the new references from Brazos. It was only on January 10, 2022, when 

Defendants served their First Invalidity Contentions, that Defendants first disclosed to Brazos their 

intent to rely on the new references in this litigation. Id. 

On page 9 of Defendants’ Motion, Defendants rely on several cases that Defendants assert 

permit amendment of Invalidity Contentions based on continuous effort, but those cases are 

Case 6:20-cv-00485-ADA Document 173 Filed 03/30/22 Page 9 of 14
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inapposite. In Maxell, for example, the Court found diligence where the defendant had to locate 

technical information for prior art products sold twenty years earlier for which there was no 

centralized database cataloging such products—a situation completely different than that 

presented here. Maxell Ltd. v. Apple Inc., No. 5:19-CV-00036-RWS, 2020 WL 10456917, at *2 

(E.D. Tex. Feb. 24, 2020). 

In Uniloc, the Court permitted leave to supplement because certain material was nonpublic information held by a third party, whereas Defendants’ new references here are all 

publicly available materials. Uniloc 2017 LLC v. Google LLC, No. 2:18-CV-00493-JRG-RSP, 

2019 WL 6465318, at *1 (E.D. Tex. Dec. 2, 2019). In Ohio Willow Wood, the Court granted leave 

to amend where the defendant delayed disclosing a newly discovered videotape for just one month, 

based on a briefing schedule for the issue of obviousness, and there was no prejudice or risk of 

delay because all deadlines in the case were already stayed. Ohio Willow Wood, 2009 WL 

10677580, at *2-3. By contrast, Defendants here could have discovered the new references earlier 

had they been diligent, and, to make matters worse, concealed the references from Brazos for 

several months without any justification. 

Because Defendants were not diligent in discovering or disclosing the newly alleged prior 

art references, Defendants cannot show good cause to amend their invalidity contentions. 

B. The Three New References Are Not Essential to Defendants’ Case 

The three new references are not vital to Defendants’ case. Defendants already identified 

41 prior art references that allegedly render the claims of the ’309 patent obvious or anticipated, 

including 6 references that alone allegedly anticipate the patent’s claims. The USPTO’s grant of 

ex parte reexamination does nothing to change that. 

Further, if these references were indeed so important, then the lack of diligence shown by 

Defendants was not commensurate with the alleged importance of these references. 

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MacroSolve, Inc. v. Antenna Software, Inc., No. 6:11-CV-287-MHS-JDL, 2013 WL 3833079, at 

*4 (E.D. Tex. July 23, 2013), citing Cummins-Allison Corp. v. SBM Co., Ltd., No. CIV.A. 9:07-

CV-196, 2009 WL 763926, at *1 (E.D. Tex. Mar. 19, 2009) (“[T]he right to amend is subject to 

the court’s duty to avoid unfairly prejudicing Plaintiff ‘through eleventh-hour alterations.’”). 

C. WSOU Would Be Unfairly Prejudiced by the Proposed Amendments 

WSOU will be unfairly prejudiced by Defendants’ untimely attempt to add new references 

to their Invalidity Contentions. Defendants admittedly discovered the new references in September 

and October of 2021, and kept WSOU and the Court in the dark while they took advantage of their 

position to prepare their ex parte reexamination request. For several months, Defendants prepared 

their reexamination request without disclosing the references, and only notified WSOU after they 

filed the request with the USPTO. Defendants waited another month to serve Amended Invalidity 

Contentions in January 2022 -- more than 6 months after Defendants’ deadline for serving Final 

Invalidity Contentions and several months after their purported first discovery of the references. 

Defendants should not be allowed to delay or expand the proceedings for their strategic benefit. 

Finally, a showing of prejudice is not required to defeat Defendants’ motion for leave to 

amend where Defendants cannot meet their burden of establishing good cause in the first place. 

As another district court in this State has held, “[a] lack of prejudice to [the plaintiff], supposing 

that there was truly no prejudice, is not sufficient to demonstrate good cause without more; to hold 

otherwise would change the showing from one of good cause to one of no prejudice and absolve 

the movant from failure based on harm to the opposing party alone.” Seven Networks, LLC v. 

Google, LLC, No. 2:17-cv-442, Dkt. 198, slip copy at 2 (E.D. Tex. June 8, 2018). 

CONCLUSION 

WHEREFORE, Plaintiff Brazos respectfully requests that the Court deny Defendants’ 

Motion for Leave to Amend Invalidity Contentions. 

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Dated: March 30, 2022 RESPECTFULLY SUBMITTED, 

By: /s/ Jonathan K. Waldrop

Jonathan K. Waldrop (CA Bar No. 297903) 

(Admitted in this District) 

jwaldrop@kasowitz.com 

Darcy L. Jones (CA Bar No. 309474) 

(Admitted in this District) 

djones@kasowitz.com 

Marcus A. Barber (CA Bar No. 307361) 

(Admitted in this District) 

mbarber@kasowitz.com 

Heather S. Kim (CA Bar No. 277686) 

(Admitted in this District) 

hkim@kasowitz.com 

John W. Downing (CA Bar No. 252850) 

(Admitted in this District) 

jdowning@kasowitz.com 

ThucMinh Nguyen (CA Bar No. 304382) 

(Admitted in this District) 

tnguyen@kasowitz.com 

KASOWITZ BENSON TORRES LLP 

333 Twin Dolphin Drive, Suite 200 

Redwood Shores, California 94065 

Telephone: (650) 453-5170 

Facsimile: (650) 453-5171 

Hershy Stern (NY Bar No. 4631024) 

(Admitted pro hac vice) 

hstern@kasowitz.com 

Joshua A. Whitehill (NY Bar No. 4766473) 

(Admitted pro hac vice) 

jwhitehill@kasowitz.com 

Shelley Ivan (NY Bar No. 4338067) 

(Admitted pro hac vice) 

sivan@kasowitz.com 

KASOWITZ BENSON TORRES LLP 

1633 Broadway 

New York, New York 10019 

Telephone: (212) 506-1700 

Facsimile: (212) 506-1800 

Mark D. Siegmund (TX Bar No. 24117055) 

mark@swclaw.com 

STECKLER WAYNE COCHRAN CHERRY 

PLLC 

Case 6:20-cv-00485-ADA Document 173 Filed 03/30/22 Page 12 of 14
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8416 Old McGregor Road 

Waco, TX 76712 

Telephone: (254) 651-3690 

Facsimile: (254) 651-3689 

Attorneys for Plaintiff 

WSOU INVESTMENTS, LLC d/b/a 

BRAZOS LICENSING AND DEVELOPMENT 

Case 6:20-cv-00485-ADA Document 173 Filed 03/30/22 Page 13 of 14
CERTIFICATE OF SERVICE 

A true and correct copy of the foregoing instrument was served or delivered electronically 

to all counsel of record, on this 30th day of March, 2022, via the Court’s CM/ECF system. 

/s/ Jonathan K. Waldrop

Jonathan K. Waldrop 

Case 6:20-cv-00485-ADA Document 173 Filed 03/30/22 Page 14 of 14