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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.

ZTE CORPORATION, ZTE (USA) 

INC., AND ZTE (TX), INC. 

Defendants.

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CIVIL ACTION NO. 6:20-cv-211

JURY TRIAL DEMANDED

ORIGINAL COMPLAINT FOR PATENT 

INFRINGEMENT

Plaintiff WSOU Investments, LLC d/b/a Brazos Licensing and Development (“Brazos” 

or “Plaintiff”), by and through its attorneys, files this Complaint for Patent Infringement against 

Defendants ZTE Corporation, ZTE (USA), Inc. and ZTE (TX), Inc. (collectively “ZTE” or 

“Defendants”) and alleges:

NATURE OF THE ACTION

1. This is a civil action for patent infringement arising under the Patent Laws of the 

United States, 35 U.S.C. §§ 1, et seq., including §§ 271, 281, 284, and 285.

THE PARTIES

2. Brazos is a limited liability corporation organized and existing under the laws of 

Delaware, with its principal place of business at 605 Austin Ave, Ste 6, Waco, TX 76701.

3. On information and belief, Defendant Zhongxing Telecommunications 

Equipment (abbreviated as “ZTE”) Corporation is a Chinese corporation that does business in 

Texas, directly or through intermediaries, with a principal place of business at ZTE Plaza, Keji 

Road South, Hi-Tech Industrial Park, Nanshan District, Shenzhen China.

Case 6:20-cv-00211-ADA Document 1 Filed 03/23/20 Page 1 of 14
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4. On information and belief, Defendant ZTE (USA) Inc. is a New Jersey 

corporation that does business in Texas, directly or through intermediaries, with a principal place 

of business in business in Richardson, Texas.

5. On information and belief, Defendant ZTE (TX) Inc. is a Texas corporation that 

does business in Texas, directly or through intermediaries, with a principal place of business in 

business in Austin, Texas.

6. All of the Defendants operate under and identify with the trade name “ZTE.” 

Each of the Defendants may be referred to individually as a “ZTE Defendant” and, collectively, 

Defendants may be referred to below as “ZTE” or as the “ZTE Defendants.”

JURISDICTION AND VENUE

7. This is an action for patent infringement which arises under the Patent Laws of 

the United States, in particular, 35 U.S.C. §§271, 281, 284, and 285.

8. This Court has jurisdiction over the subject matter of this action under 28 U.S.C.

§§ 1331 and 1338(a).

9. This Court has specific and general personal jurisdiction over each ZTE

Defendant pursuant to due process and/or the Texas Long Arm Statute, because each ZTE

Defendant has committed acts giving rise to this action within Texas and within this judicial 

district. The Court’s exercise of jurisdiction over each ZTE Defendant would not offend 

traditional notions of fair play and substantial justice because ZTE has established minimum 

contacts with the forum. For example, on information and belief, ZTE Defendants have 

committed acts of infringement in this judicial district, by among other things, selling and 

offering for sale products that infringe the asserted patent, directly or through intermediaries, as 

alleged herein.

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10. Venue in the Western District of Texas is proper pursuant to 28 U.S.C. §§1391

and/or 1400(b). The ZTE Defendants have committed acts of infringement and have places of 

businesses in this District and/or are foreign entities for purpose of §1391. As non-limiting 

examples, ZTE (TX) has maintained a place of business at 7000 N MO-PAC EXPRESSWAY 

200 AUSTIN, TX 7873; and, ZTE (USA) has maintained a place of business at 6500 River Place 

Blvd., Austin, TX 78730. ZTE Corporation also describes a “research-and-development center 

in Austin, Texas.”1

COUNT ONE - INFRINGEMENT OF 

U.S. PATENT NO. 8,451,839

11. Brazos re-alleges and incorporates by reference the preceding paragraphs of this 

Complaint.

12. On May 28, 2013, the United States Patent and Trademark Office duly and legally 

issued U.S. Patent No. 8,451,839 (“the ’839 Patent”), entitled “METHOD AND APPARATUS 

FOR MANAGING ROUTE INFORMATION AND FORWARDING DATA IN ACCESS 

DEVICES.” A true and correct copy of the ’839 Patent is attached as Exhibit A to this Complaint.

13. Brazos is the owner of all rights, title, and interest in and to the ’839 Patent, 

including the right to assert all causes of action arising under the ’839 Patent and the right to any 

remedies for the infringement of the ’839 Patent.

14. ZTE makes, uses, sells, offers for sale, imports, and/or distributes, in the United 

States, networking products including routing switches (collectively, the “Accused Products”). 

15. The Accused Products include ZXR10 5900E series routing switches, including 

ZXR10 5916E, 5938E, 5928E-FI, and 5952E routing switches.

1 https://res-www.zte.com.cn/mediares/magazine/publication/tech_en/pdf/201009.pdf

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https://www.zte.com.cn/global/products/bearer/data_communication/ethernet_switch/5900EEN.

16. The Accused Products support Layer 2 features. ZTE Series switches can serve 

as an aggregation switch in various scenarios including Metro area networks and IP RAN. The 

Accused Products present ways to manage route information such as IP addresses, MAC 

addresses, etc.

Case 6:20-cv-00211-ADA Document 1 Filed 03/23/20 Page 4 of 14
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https://www.zte.com.cn/global/products/bearer/data_communication/ethernet_switch/5900EEN.

https://www.zte.com.cn/global/products/bearer/data_communication/ethernet_switch/5250-EN

https://www.zte.com.cn/global/products/bearer/data_communication/ethernet_switch/2900EEN

17. The Accused Products can be used to implement a Next Generation Network 

(NGN) network architecture.

https://www.zte.com.cn/global/about/magazine/zte-technologies/2005/8/en_241/161535.html

Case 6:20-cv-00211-ADA Document 1 Filed 03/23/20 Page 5 of 14
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https://www.zte.com.cn/global/about/magazine/zte-communications/2005/3/en_58/162351.html

18. The Accused Products implement a feature of MAC-Forced Forwarding (MFF), 

to isolate users at the access side. Accused ZTE switches create and maintain MFF user 

information tables (e.g., route information tables) by capturing Acknowledgement (ACK) 

packets returned by the Dynamic Host Configuration Protocol (DHCP). Further, the Accused 

Products can capture or receive the DHCP ACK packets (e.g., access response message) from 

the DHCP server in a VLAN to create and maintain the MFF user table. 

https://manualzz.com/doc/26168198/zxr10-switch-product-quick-reference-guide_international

(page 40).

Case 6:20-cv-00211-ADA Document 1 Filed 03/23/20 Page 6 of 14
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...

...

...

...

Case 6:20-cv-00211-ADA Document 1 Filed 03/23/20 Page 7 of 14
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http://www.nova-minsk.com/ZTE/59E/SJ-20150114102049-009-

ZXR10%205900E%20Series%20(V3.00.11)Configuration%20Guide%20(Security).pdf

(pages 125-126).

19. DHCP response messages (e.g., the access response messages) can be received 

by the Accused Products from a DHCP server in a VLAN. 

https://www.manualslib.com/manual/788723/Zte-Zxr10-5900-Series.html?page=113 (Page 116).

20. The Accused Products can create and maintain an MFF user table by capturing 

DHCP ACK packets (e.g., access response) and obtaining field entries of a gateway 

corresponding to an IP address associated with a client (e.g., route-related information).

...

Case 6:20-cv-00211-ADA Document 1 Filed 03/23/20 Page 8 of 14
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... 

...

http://www.nova-minsk.com/ZTE/59E/SJ-20150114102049-009-

ZXR10%205900E%20Series%20(V3.00.11)Configuration%20Guide%20(Security).pdf

(pages 125-126).

21. The lease time is the predefined time that is embedded in the DHCP messages. 

The lease time is the remaining time till which the route item, IP address associated with the 

DHCP messages, is updated. The lease time can be a long lease or a short lease.

22. The Accused Products also can obtain a lease time from DHCP ACK packets 

configured at a DHCP server

...

...

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...

https://www.manualslib.com/manual/788723/Zte-Zxr10-5900-Series.html (Pages 97, 103).

23. The Accused Products maintain (e.g., update) an MFF user information tables

(e.g., routing tables) by capturing DHCP ACK packets (e.g., access response) and obtaining field 

entries of a gateway corresponding to an IP address associated with a client (e.g., route-related 

information). A corresponding entry between an IP and a MAC address of each user and a 

gateway IP address can be changed when a new DHCP request message is sent upon an

expiration of lease time. Accordingly, an MFF user information table (e.g., route table item) can 

be updated. 

...

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...

...

...

http://www.nova-minsk.com/ZTE/59E/SJ-20150114102049-009-

ZXR10%205900E%20Series%20(V3.00.11)Configuration%20Guide%20(Security).pdf

(pages 125-126).

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24. In view of preceding paragraphs, each and every element of at least claim 1 of 

the ’839 Patent is found in the Accused Products.

25. ZTE has and continues to directly infringe at least one claim of the ’839 Patent, 

literally or under the doctrine of equivalents, by making, using, selling, offering for sale, 

importing, and/or distributing the Accused Products in the United States, including within this 

judicial district, without the authority of Brazos.

26. ZTE has received notice and actual or constructive knowledge of the ’839 Patent 

since at least the date of service of this Complaint.

27. Since at least the date of service of this Complaint, through its actions, ZTE has 

actively induced product makers, distributors, retailers, and/or end users of the Accused Products 

to infringe the ’839 Patent throughout the United States, including within this judicial district, 

by, among other things, advertising and promoting the use of the Accused Products in various 

websites, including providing and disseminating product descriptions, operating manuals, and 

other instructions on how to implement and configure the Accused Products. Examples of such 

advertising, promoting, and/or instructing include the documents at:

• https://www.zte.com.cn/global/products/bearer/data_communication/ethernet_swit

ch/2900E-EN

• https://manualzz.com/doc/26168198/zxr10-switch-product-quick-referenceguide_international

• http://www.nova-minsk.com/ZTE/59E/SJ-20150114102049-009-

ZXR10%205900E%20Series%20(V3.00.11)Configuration%20Guide%20(Securit

y).pdf

• https://www.manualslib.com/manual/788723/Zte-Zxr10-5900-Series.html

• https://www.zte.com.cn/global/about/magazine/ztetechnologies/2005/8/en_241/161535.html

• https://www.zte.com.cn/global/about/magazine/ztecommunications/2005/3/en_58/162351.html

• https://www.zte.com.cn/global/products/bearer/data_communication/ethernet_swit

ch/5250-EN

• https://www.zte.com.cn/global/products/bearer/data_communication/ethernet_swit

ch/2900E-EN

Case 6:20-cv-00211-ADA Document 1 Filed 03/23/20 Page 12 of 14
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• https://www.manualslib.com/download/788723/Zte-Zxr10-5900-Series.html

28. Since at least the date of service of this Complaint, through its actions, ZTE has 

contributed to the infringement of the ’839 Patent by having others sell, offer for sale, or use the 

Accused Products throughout the United States, including within this judicial district, with

knowledge that the Accused Products infringe the ’839 Patent. The Accused Products are 

especially made or adapted for infringing the ’839 Patent and have no substantial non-infringing 

use. For example, in view of the preceding paragraphs, the Accused Products contain 

functionality which is material to at least one claim of the ’839 Patent.

JURY DEMAND

Brazos hereby demands a jury on all issues so triable.

REQUEST FOR RELIEF

WHEREFORE, Brazos respectfully requests that the Court:

(A) Enter judgment that ZTE infringes one or more claims of the ’839 Patent literally 

and/or under the doctrine of equivalents;

(B) Enter judgment that ZTE has induced infringement and continues to induce 

infringement of one or more claims of the ’839 Patent;

(C) Enter judgment that ZTE has contributed to and continues to contribute to the 

infringement of one or more claims of the ’839 Patent;

(D) Award Brazos damages, to be paid by ZTE in an amount adequate to compensate 

Brazos for such damages, together with pre-judgment and post-judgment interest for the 

infringement by ZTE of the ’839 Patent through the date such judgment is entered in accordance 

with 35 U.S.C. §284, and increase such award by up to three times the amount found or assessed 

in accordance with 35 U.S.C. §284;

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(E) Declare this case exceptional pursuant to 35 U.S.C. §285; and

(F) Award Brazos its costs, disbursements, attorneys’ fees, and such further and 

additional relief as is deemed appropriate by this Court.

Dated: March 23, 2020 Respectfully submitted,

/s/ James L. Etheridge

James L. Etheridge

Texas State Bar No. 24059147 

Ryan S. Loveless

Texas State Bar No. 24036997 

Travis L. Richins

Texas State Bar No. 24061296

ETHERIDGE LAW GROUP, PLLC

2600 E. Southlake Blvd., Suite 120 / 324

Southlake, Texas 76092

Telephone: (817) 470-7249

Facsimile: (817) 887-5950

Jim@EtheridgeLaw.com

Ryan@EtheridgeLaw.com

Travis@EtheridgeLaw.com

COUNSEL FOR PLAINTIFF

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