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IN THE UNITED STATES DISTRICT COURT

FOR THE EASTERN DISTRICT OF TEXAS

MARSHALL DIVISION

WINTERSPRING DIGITAL LLC,

Plaintiff,

v.

RENESAS ELECTRONICS 

CORPORATION,

Defendant.

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Case No. 

JURY TRIAL DEMANDED

COMPLAINT FOR PATENT INFRINGEMENT

Plaintiff Winterspring Digital LLC (“Winterspring” or “Plaintiff”) for its Complaint 

against Renesas Electronics Corporation (“Renesas” or “Defendant”) alleges as follows: 

THE PARTIES

1. Winterspring is a limited liability company organized and existing under the laws 

of the State of Texas, with its principal place of business located at 104 East Houston Street, 

Marshall, Texas 75670

2. Upon information and belief, Renesas is a Japanese corporation, with a principal 

place of business located at Toyosu Foresia, 3-2-24 Toyosu, Koto-ku, Tokyo 135-0061, Japan. 

Upon information and belief, Renesas does business in Texas and in the Eastern District of Texas, 

directly or through intermediaries.

JURISDICTION

3. This is an action for patent infringement arising under the patent laws of the United 

States, 35 U.S.C. §§ 1, et seq. This Court has jurisdiction over this action pursuant to 28 U.S.C. 

§§ 1331 and 1338(a). 

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4. This Court has personal jurisdiction over Defendant. Defendant regularly conducts 

business and has committed acts of patent infringement and/or has induced acts of patent 

infringement by others in this Judicial District and/or has contributed to patent infringement by 

others in this Judicial District, the State of Texas, and elsewhere in the United States. 

5. Venue is proper in this Judicial District pursuant to 28 U.S.C. § 1391 because, 

among other things, Defendant is not a resident in the United States, and thus may be sued in any 

judicial district pursuant to 28 U.S.C. § 1391(c)(3).

6. Defendant is subject to this Court’s jurisdiction pursuant to due process and/or the 

Texas Long Arm Statute due at least to its substantial business in this State and Judicial District, 

including (a) at least part of its past infringing activities, (b) regularly doing or soliciting business 

in Texas, and/or (c) engaging in persistent conduct and/or deriving substantial revenue from goods 

and services provided to customers in Texas. 

PATENTS-IN-SUIT

7. On January 16, 2007, the United States Patent and Trademark Office duly and 

legally issued U.S. Patent No. 7,164,692 (the “’692 Patent”) entitled “Apparatus and Method for

Transmitting 10 Gigabit Ethernet LAN Signals Over a Transport System.” A true and correct copy 

of the ’692 Patent is available at http://pdfpiw.uspto.gov/.piw?docid=7164692.

8. On September 2, 2008, the United States Patent and Trademark Office duly and 

legally issued U.S. Patent No. 7,420,975 (the “’975 Patent”) entitled “Method and Apparatus For 

High-Speed Frame Tagger.” A true and correct copy of the ’975 Patent is available at 

http://pdfpiw.uspto.gov/.piw?docid=7420975.

9. On August 10, 2010, the United States Patent and Trademark Office duly and 

legally issued U.S. Patent No. 7,774,468 (the “’468 Patent”) entitled “Network Traffic Admission 

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Control.” A true and correct copy of the ’468 Patent is available at 

http://pdfpiw.uspto.gov/.piw?docid=7774468.

10. Winterspring is the sole and exclusive owner of all right, title, and interest in the 

’692, ’975, and ’468, Patents (the “Patents-in-Suit”) and holds the exclusive right to take all actions 

necessary to enforce its rights to the Patent-in-Suit, including the filing of this patent infringement 

lawsuit. Winterspring also has the right to recover all damages for past, present, and future 

infringement of the Patents-in-Suit and to seek injunctive relief as appropriate under the law. 

FACTUAL ALLEGATIONS

11. The Patents-in-Suit generally cover systems and methods for routing data over a 

network.

12. The ’692 Patent generally discloses an apparatus and method for transmitting LAN 

signals over a transport system. A system sends or receives a signal to or from a transport system, 

converts the signal to an intermediate form, re-clocks the intermediate signal, reconverts and then 

transmits the signal. The technology described in the ’692 Patent was developed by Jeffrey Lloyd 

Cox and Samir Satish Seth. By way of example, this technology is implemented today in 

microchips, SoCs and ASICs the receive, convert, monitor, and send 10-Gigabit LAN signals.

13. The ’975 Patent discloses an apparatus and methods for examining a packet, 

determining a protocol type and tagging the packet. The technology described in the ’975 Patent 

was developed by Velamur Krishnamachari and Dinesh Annayya from Cypress Semiconductor 

Corporation. By way of example, this technology is implemented today in microchips, SoCs and 

ASICs which implement packet tagging.

14. The ’468 Patent discloses systems and methods for traffic admission control using 

real time bandwidth allocation. The technology described in the ’468 Patent was developed by 

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Siddhartha Nag, and Srikanth S. Kumar. By way of example, this technology is implemented 

today in microchips, SoCs, and ASICs that perform traffic admission control using real time 

bandwidth allocation.

15. Renesas has infringed and is continuing to infringe the Patents-in-Suit by making, 

using, offering to sell, selling, and/or importing network switches, routers, and software which 

implement the technology disclosed in the above patents-in-suit. 

COUNT I

(Infringement of the ’692 Patent)

16. Paragraphs 1 through 15 are incorporated by reference as if fully set forth herein.

17. Winterspring has not licensed or otherwise authorized Defendant to make, use, 

offer for sale, sell, or import any products that embody the inventions of the ’692 Patent.

18. Defendant has and continues to directly infringe the ’692 Patent, either literally or 

under the doctrine of equivalents, without authority and in violation of 35 U.S.C. § 271, by making, 

using, offering to sell, selling, and/or importing into the United States products that satisfy each 

and every limitation of one or more claims of the ’692 Patent. Such products include ethernet 

Network Adaptors and Controllers, PHYs, ethernet switches, and optical modules, optical 

interconnects, and network synchronization tools that receive, convert, monitor, and send 10GE 

LAN signals.

19. For example, Defendant has and continues to directly infringe at least claim 10 of 

the ’692 Patent by making, using, offering to sell, selling, and/or importing into the United States 

products that receive, convert, and monitor 10GE LAN signals. 

20. For example, the Renesas 82P33741 Port Synchronizer performs a method 

transferring 10GE LAN client signals from a transport system to a client system comprising 

receiving the 10GE LAN client signal transmitted over the transport system, converting the 10GE 

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LAN client signal to an intermediate signal, recovering clock data from the intermediate signal, 

recovering a data stream from the intermediate signal, reconverting the intermediate signal to the 

10GE LAN client signal; transferring the 10GE LAN client signal to a client system; and 

monitoring the intermediate form with a monitoring device wherein the monitoring device is a 

10GE LAN media access controller. 

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“Renesas Port Synchronizer for IEEE 1588 and 10G/40G/100G Synchronous Ethernet: Datasheet” at Pg. 1. 

Available at: https://www.renesas.com/us/en/document/dst/82p33741-datasheet?r=117281. 

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21. Defendant has and continues to indirectly infringe one or more claims of the ’692 

Patent by knowingly and intentionally inducing others, including Renesas customers and endusers, to directly infringe, either literally or under the doctrine of equivalents, by making, using, 

offering to sell, selling and/or importing into the United States microchips, SoCs, ASICs and other 

products that receive, convert, monitor, and send 10GE LAN signals. 

22. Defendant, with knowledge that these products, or the use thereof, infringe the ’692 

Patent at least as of the date of this Complaint, knowingly and intentionally induced, and continues 

to knowingly and intentionally induce, direct infringement of the ’692 Patent by providing these 

products to end users for use in an infringing manner. 

23. Defendant induced infringement by others, including end users, with the intent to 

cause infringing acts by others or, in the alternative, with the belief that there was a high probability

that others, including end users, infringe the ’692 Patent, but while remaining willfully blind to the 

infringement.

24. Winterspring has suffered damages as a result of Defendant’s direct and indirect 

infringement of the ’692 Patent in an amount to be proved at trial.

25. Winterspring has suffered, and will continue to suffer, irreparable harm as a result 

of Defendant’s infringement of the ’692 Patent, for which there is no adequate remedy at law, 

unless Defendant’s infringement is enjoined by this Court.

COUNT II

(Infringement of the ’975 Patent)

26. Paragraphs 1 through 15 are incorporated by reference as if fully set forth herein.

27. Winterspring has not licensed or otherwise authorized Defendant to make, use, 

offer for sale, sell, or import any products that embody the inventions of the ’975 Patent.

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28. Defendant has and continues to directly infringe the ’975 Patent, either literally or 

under the doctrine of equivalents, without authority and in violation of 35 U.S.C. § 271, by making, 

using, offering to sell, selling, and/or importing into the United States products that satisfy each 

and every limitation of one or more claims of the ’975 Patent. Such products include but are not 

limited to network adaptors and controllers and ethernet switches that perform packet tagging. 

29. For example, Defendant has and continues to directly infringe at least claim 5 of 

the ’975 Patent by making, using, offering to sell, selling, and/or importing into the United States 

products that perform packet tagging:

30. For example, the Renesas RZ/N1D includes an apparatus comprising a network 

processor interface suitable for coupling to a network processor and a central processor interface 

suitable for coupling to a central processor. Upon information and belief, the Renesas RZ/N1D 

further includes a protocol determination logic block to determine a protocol type of data in a 

packet, wherein the protocol determination logic compares the protocol information in a first pass 

to predetermined values to procedure a first result and, if the first result is positive, compares the 

protocol information in a second pass to predetermined values to produce a second result, the first 

and second results forming a set of results. Upon information and belief, the Renesas RZ/N1D 

further comprises a tag select logic block to apply a tag to the packet indicating that the packet has 

an unknown protocol type if the first result is negative and if the first result is positive, the packet 

should be sent to either the central processor interface or the network processor interface based on 

the set of results. 

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31. Defendant has and continues to indirectly infringe one or more claims of the ’975 

Patent by knowingly and intentionally inducing others, including Renesas customers and endusers, to directly infringe, either literally or under the doctrine of equivalents, by making, using, 

offering to sell, selling and/or importing into the United States products that include microchips, 

SoCs, ASICs and other products that implement packet tagging.

32. Defendant, with knowledge that these products, or the use thereof, infringed the 

’975 Patent at least as of the date of this Complaint, knowingly and intentionally induced, and 

continues to knowingly and intentionally induce, direct infringement of the ’975 Patent by 

providing these products to end users for use in an infringing manner. 

33. Defendant induced infringement by others, including end users, with the intent to 

cause infringing acts by others or, in the alternative, with the belief that there was a high probability 

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“Renesas RZ/N1D Group, RZ/N1S Group, RZ/N1L Group User Manual: R-IN Engine and 

Ethernet Peripherals: User Manual” at. Pg. 114. Available at: 

https://www.renesas.com/us/en/document/mah/rzn1d-group-rzn1s-group-rzn1l-group-usersmanual-r-engine-and-ethernet-peripherals?language=en. 

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“Renesas RZ/N1D Group, RZ/N1S Group, RZ/N1L Group User Manual: R-IN Engine and 

Ethernet Peripherals: User Manual” at. Pg. 114. Available at: 

https://www.renesas.com/us/en/document/mah/rzn1d-group-rzn1s-group-rzn1l-group-usersmanual-r-engine-and-ethernet-peripherals?language=en. 

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that others, including end users, infringe the ’975 Patent, but while remaining willfully blind to the 

infringement.

34. Winterspring has suffered damages as a result of Defendant’s direct and indirect 

infringement of the ’975 Patent in an amount to be proved at trial.

35. Winterspring has suffered, and will continue to suffer, irreparable harm as a result 

of Defendant’s infringement of the ’975 Patent, for which there is no adequate remedy at law, 

unless Defendant’s infringement is enjoined by this Court.

COUNT III

(Infringement of the ’468 Patent)

36. Paragraphs 1 through 15 are incorporated by reference as if fully set forth herein.

37. Winterspring has not licensed or otherwise authorized Defendant to make, use, 

offer for sale, sell, or import any products that embody the inventions of the ’468 Patent.

38. Defendant has and continues to directly infringe the ’468 Patent, either literally or 

under the doctrine of equivalents, without authority and in violation of 35 U.S.C. § 271, by making, 

using, offering to sell, selling, and/or importing into the United States products that satisfy each 

and every limitation of one or more claims of the ’468 Patent. Such products include but are not 

limited to network adaptors and controllers and ethernet switches which allow for traffic admission 

control using real time bandwidth allocation.

39. For example, Defendant has and continues to directly infringe at least claim 1 of 

the ’468 Patent by making, using, offering to sell, selling, and/or importing into the United States 

products that hardware and software which allow for traffic admission control using real time 

bandwidth allocation. 

40. For example, the Renesas 89TTM552 Traffic Manager performs a method of a first 

edge node requesting from a director node, an amount of bandwidth over a first of a plurality of 

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paths in a network between the first edge node and a second edge node, wherein the director node 

is configured to maintain information indicative of bandwidth available along each of the plurality 

of paths. Upon information and belief, in response to the requested amount of bandwidth being 

available along the first path, the Renesas 89TTM552 Traffic Manager performs the step of the 

first edge node receiving, from the director node, an allocation of bandwidth as a real-time 

bandwidth pool associated with network resources in the first path. Upon information and belief, 

the Renesas 89TTM552 Traffic Manager performs the step of the first edge node receiving a 

connection request to establish a first real-time communication session between one of a first 

plurality of communication devices coupled to the first edge node and one of a second plurality of 

communication devices coupled to the second edge node. Upon information and belief, in 

response to determining that network resources in the real-time bandwidth pool are available to 

permit communication over the first path, the Renesas 89TTM552 Traffic Manager performs the 

step of the first edge node responding to the connection request by allocating a portion of the realtime bandwidth pool to the first real-time communication session.

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“Renesas 89TTM552 Traffic Manager Data Sheet” at. Pg. 1. Available at: 

https://www.renesas.com/us/en/document/dst/89ttm552-traffic-manager-data-sheet. 

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Id. at 2. 

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41. Defendant has and continues to indirectly infringe one or more claims of the ’468 

Patent by knowingly and intentionally inducing others, including Renesas customers and endusers, to directly infringe, either literally or under the doctrine of equivalents, by making, using, 

offering to sell, selling and/or importing into the United States products that include microchips, 

SoCs, ASICs and other products which allow for traffic admission control using real time 

bandwidth allocation. 

42. Defendant, with knowledge that these products, or the use thereof, infringe the ’468

Patent at least as of the date of this Complaint, knowingly and intentionally induced, and continues 

to knowingly and intentionally induce, direct infringement of the ’468 Patent by providing these 

products to end users for use in an infringing manner. 

43. Defendant induced infringement by others, including end users, with the intent to 

cause infringing acts by others or, in the alternative, with the belief that there was a high probability 

that others, including end users, infringe the ’468 Patent, but while remaining willfully blind to the 

infringement.

44. Winterspring has suffered damages as a result of Defendant’s direct and indirect 

infringement of the ’468 Patent in an amount to be proved at trial.

45. Winterspring has suffered, and will continue to suffer, irreparable harm as a result 

of Defendant’s infringement of the ’468 Patent, for which there is no adequate remedy at law, 

unless Defendant’s infringement is enjoined by this Court.

DEMAND FOR JURY TRIAL

Plaintiff hereby demands a jury for all issues so triable.

PRAYER FOR RELIEF

WHEREFORE, Winterspring prays for relief against Defendant as follows:

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a. Entry of judgment declaring that Defendant has directly and/or indirectly infringed 

one or more claims of the Patents-in-Suit;

b. An order pursuant to 35 U.S.C. § 283 permanently enjoining Defendant, its 

officers, agents, servants, employees, attorneys, and those persons in active concert or 

participation with it, from further acts of infringement of one or more of the Patents-in-Suit; 

c. An order awarding damages sufficient to compensate Winterspring for 

Defendant’s infringement of the Patents-in-Suit, but in no event less than a reasonable royalty, 

together with interest and costs;

d. Entry of judgment declaring that this case is exceptional and awarding 

Winterspring its costs and reasonable attorney fees under 35 U.S.C. § 285; and,

e. Such other and further relief as the Court deems just and proper.

Dated: January 23, 2023 Respectfully submitted,

/s/ Vincent J. Rubino, III

Alfred R. Fabricant

NY Bar No. 2219392

Email: ffabricant@fabricantllp.com

Peter Lambrianakos

NY Bar No. 2894392

Email: plambrianakos@fabricantllp.com

Vincent J. Rubino, III

NY Bar No. 4557435

Email: vrubino@fabricantllp.com

FABRICANT LLP

411 Theodore Fremd Road, Suite 206 South 

Rye, NY 10580

Telephone: (212) 257-5797

Facsimile: (212) 257-5796 

Justin Kurt Truelove

Texas Bar No. 24013653

Email: kurt@truelovelawfirm.com

TRUELOVE LAW FIRM, PLLC

100 West Houston

Marshall, Texas 75670

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Telephone: (903) 938-8321

Facsimile: (903) 215-8510

ATTORNEYS FOR PLAINTIFF

WINTERSPRING DIGITAL LLC.

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