1

IN THE UNITED STATES DISTRICT COURT

FOR THE WESTERN DISTRICT OF TEXAS

WACO DIVISION

NIPPON TELEGRAPH AND )

TELEPHONE CORPORATION and )

ESSENTIAL WIFI LLC, )

)

Plaintiffs, ) C. A. No. 6:20-cv-225

)

v. ) JURY TRIAL DEMANDED

)

MEDIATEK INC. AND )

MEDIATEK USA INC., )

)

Defendants. )

COMPLAINT

Plaintiffs Nippon Telegraph and Telephone Corporation (“NTT”) and Essential WiFi,

LLC (“EWF”) (collectively, “Plaintiffs”) bring this action against MediaTek Inc. (“MT”) and 

MediaTek U.S.A. Inc. (“MTUS”) (collectively, “Defendants”) and allege as follows.

NATURE OF THE ACTION

1. This is an action for patent infringement. Defendants MT and MTUS have 

infringed and continue to infringe, contribute to the infringement of, and/or actively induce 

others to infringe U.S. Patent Nos. 7,280,551 (“the ’551 Patent”), No. 7,545,781 (“the ’781 

Patent”), No. 7,400,616 (“the ’616 Patent”), and No. 7,242,720 (“the ’720 Patent”) (collectively, 

the “Patents in Suit”). 

2. The Patents in Suit are “Standard Essential Patents” (“SEPs”), meaning that they 

are essential to the implementation of widely adopted standards, in this case pertaining to 

wireless communications over local area networks (“WiFi”).

3. Plaintiffs are prepared to grant a license to Defendants’ infringing products 

(“Accused Products”) on terms and conditions that are fair, reasonable, and non-discriminatory 

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(“FRAND”). Plaintiffs bring this action because Defendants have refused Plaintiffs’ FRAND 

offers and have refused to negotiate in good faith, but continue to practice, use, or otherwise 

comply with the WiFi standards covered by the Patents in Suit. 

4. Specifically, Defendants are unwilling licensees in the face of Plaintiffs’ good 

faith offers to license the Patents in Suit under FRAND terms. Instead, because Defendants 

continue to willfully practice the Patents in Suit without a license, Plaintiffs have been forced to 

bring this action against Defendants.

5. Plaintiffs further bring this Declaratory Judgment action to establish that 

Plaintiffs have complied with their FRAND commitment regarding the Patents in Suit and that 

Defendants are unwilling licensees. 

THE PARTIES

6. Plaintiff Nippon Telegraph and Telephone Corporation is a corporation organized 

under the laws of Japan, and headquartered in Tokyo, Japan.

7. Plaintiff Essential WiFi LLC is a company organized under Texas law with its 

principal offices in Austin, Texas.

8. On information and belief, Defendant MT is a corporation organized and existing 

under the laws of Taiwan, with its principal place of business located at No. 1, Dusing Road 1, 

Hsinchu Science Park, Hsinchu City 30078, Taiwan.

9. On information and belief, Defendant MTUS is a Delaware corporation and a 

wholly owned subsidiary of MT. On information and belief, MTUS maintains a place of 

business at 5914 W. Courtyard Drive, Austin, Texas 78730. On information and belief, MTUS 

is registered to conduct business in Texas and may be served through its registered agent, CT 

Corporation System, 1999 Bryan Street, Suite 900, Dallas, Texas 75201-3136. 

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JURISDICTION AND VENUE

10. This action arises under the Patent Laws of the United States, 35 U.S.C. § 1 

et seq. This Court has jurisdiction over the subject matter of this action pursuant to 28 U.S.C. §§ 

1331 and 1338(a).

11. This Court has personal jurisdiction over MT and MTUS because, directly or 

through intermediaries, each has committed acts within the Western District of Texas giving rise 

to this action and/or has established minimum contacts with the Western District of Texas, such 

that the exercise of jurisdiction would not offend traditional notions of fair play and substantial 

justice.

12. In particular, Defendant MT has directed numerous communications into this 

District to Plaintiff EWF in the course of discussing potential licenses to the Patents in Suit. 

13. Further, on information and belief, Defendant MTUS maintains one or more 

physical fixed places of business in Texas, including offices at 5914 W. Courtyard Drive, Austin, 

Texas 78730. 

14. In addition, MT and MTUS have placed or contributed to placing products that 

infringe the Patents in Suit (the “Accused Products”) into the stream of commerce via an

established distribution channel knowing or understanding that such products would be sold and

used in the United States, including in the Western District of Texas.

15. On information and belief, MT and MTUS also have each derived substantial 

revenue from infringing acts in the Western District of Texas, including from the sale and use of 

Accused Products.

16. Venue is proper under 28 U.S.C. § 1391(b)-(c) and 28 U.S.C. § 1400. In 

particular, venue is proper as to a foreign defendant in any district. 28 U.S.C. § 1391(c)(3); In re 

HTC Corp., 889 F.3d 1349 (Fed. Cir. 2018). Defendant MT is a foreign corporation.

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17. Further, venue is proper as to Defendant MTUS because it maintains one or more 

physical fixed places of business in Texas, including offices at 5914 W. Courtyard Drive, Austin, 

Texas 78730. 

18. Joinder of Defendants is proper because Defendants are related parties who are 

either jointly and severally liable for infringement, or who make use, sell, offer for sale, or 

import the same or similar accused products that practice the same patents. Further, as 

Defendants’ infringing acts are tied to the same underlying hardware and/or software, the factual 

question of infringement will be substantially identical as between Defendants. 

BACKGROUND

19. NTT is one of the largest telecommunications companies in the world. For 

decades, NTT has devoted considerable resources to the research and development of wired and 

wireless communications technology. NTT scientists have made significant advances in this field 

and many of their inventions have been patented by NTT in the United States. As a result, NTT 

owns or has rights to various intellectual property.

20. The Institute of Electrical and Electronics Engineers (“IEEE”) is a professional 

association whose activities span a broad range of disciplines, including telecommunications. As 

part of its activities, the IEEE develops and publishes industrial standards, including standards 

pertaining to wireless communications.

21. The IEEE 802.11 standards, developed by the IEEE LAN/MAN Standards 

Committee (IEEE 802), provide a set of media access control (MAC) and physical layer (PHY) 

specifications for implementing WiFi. WiFi usage is widespread in modern electronic products, 

including laptops, smartphones, routers, televisions, cameras and other devices that have wireless 

connections.

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22. The 802.11 family of standards includes multiple versions, which can differ from 

each other in terms of speed, transmission ranges, and frequency used. 

23. For example, the first widely-adopted WiFi standard is 802.11b, which provides a 

maximum data rate of 11 Mbps using “single-input, single output” (“SISO”) antenna technology, 

or transmission of a single data stream. 

24. By contrast, the IEEE 802.11n-2009 (“802.11n”) standard utilizes multiple 

antennas to dramatically increase data throughput over that provided by prior standards. In 

particular, a primary basis for 802.11n’s increased speed is its use of “multiple-input, multipleoutput” (“MIMO”) technology, whereby multiple data streams may be transmitted and received 

simultaneously. 802.11n further provides for 40MHz transmissions over two bonded adjacent 

20MHz channels, which are designated as primary and secondary channels. The 802.11n 

standard can support a maximum theoretical data rate of up to 300 Mbps. Additional features 

implementing and enabling the advantages of the 802.11n standard are described, as appropriate, 

with reference to specific Patents in Suit below.

25. IEEE 802.11ac is an amendment to IEEE 802.11 that further builds on 802.11n. 

In particular, the 802.11ac standard substantially simplified the methods used for beamforming, 

or focusing transmitted energy toward particular receivers. 802.11ac further provided for an 

application of MIMO methods in combination with beamforming, whereby, for example, an 

access point may transmit to multiple distinct users at the same time (“MU-MIMO”). Additional 

features implementing and enabling the advantages of the 802.11ac standard are described, as 

appropriate, with reference to specific Patents in Suit below.

26. The IEEE requires participants to commit to abide by their Intellectual Property 

Rights (“IPR”) policies, which set forth the rights and obligations of their members. For 

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example, members are required to disclose intellectual property rights that disclose standard 

essential and potentially standard essential patents and patent applications relevant to IEEE 

standards. Further, the IEEE requires members disclosing IPR to indicate, via a Letter of 

Assurance (“LOA”), whether they will commit to granting implementer members a license under 

terms that are FRAND.

27. NTT has been an active participant in the IEEE’s development of industry 

standards, including many of the 802.11 standards, since at least 1998. NTT scientists have 

participated in the drafting of the specifications for WiFi standards and have disclosed NTT 

technology to the IEEE for adoption in the WiFi standards.

28. EWF is the exclusive licensee of the Patents in Suit and has the right to grant 

sublicenses, exclude others, and to enforce, sue and recover damages for past and future 

infringement of the Patents in Suit.

THE PATENTS IN SUIT

29. On October 9, 2007, United States Patent No. 7,280,551 entitled “Wireless packet 

communication method and wireless packet communication apparatus,” was duly and legally 

issued to NTT, as assignee of the inventors Kengo Nagata, Tomoaki Kumagai, Shinya Otsuki, 

Kazuyoshi Saito, and Satoru Aikawa. A copy of the ’551 Patent is attached hereto as Exhibit A.

30. On June 9, 2009, United States Patent No. 7,545,781, entitled “Wireless packet 

communication method and wireless packet communication apparatus,” was duly and legally 

issued to NTT, as assignee of the inventors Shinya Otsuki, Tomoaki Kumagai, Kengo Nagata, 

Kazuyoshi Saito, Satoru Aikawa, and Yasuhiko Inoue. A copy of the ’781 Patent is attached 

hereto as Exhibit B.

31. On July 15, 2008, United States Patent No. 7,400,616 entitled “Wireless packet 

communication method and wireless packet communication apparatus,” was duly and legally 

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issued to NTT, as assignee of the inventors Kazuyoshi Saito, Tomoaki Kumagai, Shinya Otsuki, 

Kengo Nagata, Satoru Aikawa, Atsushi Ohta, and Akinori Hirukawa. A copy of the ’616 Patent 

is attached hereto as Exhibit C.

32. On July 10, 2007, United States Patent No. 7,242,720 entitled “OFDM signal 

communication system, OFDM signal transmitting device and OFDM signal receiving device,” 

was duly and legally issued to NTT, as assignee of the inventors Takatoshi Sugiyama, Yusuke 

Asai, Satoshi Kurosaki, Masahiro Umehira, Daisei Uchida, and Yasuo Suzuki. A copy of the 

’720 Patent is attached hereto as Exhibit D.

33. On November 15, 2011, NTT notified the IEEE in a public LOA that each of the 

Patents in Suit could include Essential Patent Claims with respect to at least the IEEE 802.11n 

standard. NTT further indicated that it will grant a license to the identified SEPs under terms 

that are FRAND.

DEFENDANTS’ REFUSAL TO NEGOTIATE IN GOOD FAITH

34. On May 31, 2016, EWF provided a letter to MT conveying Plaintiffs’ willingness 

to license its portfolio of WiFi patents that included the Patents In Suit on FRAND terms. EWF 

further provided detailed exemplary claim charts explaining the manner in which MT’s Accused 

Products infringe.

35. On information and belief, MTUS acts at the direction of MT with respect to the

Accused Products, and thus MT also negotiates licenses on behalf of MTUS.

36. EWF representatives, at their own expense, traveled to Taiwan and met in person

with MT’s representatives on multiple occasions, including October 12, 2016; December 14, 

2018; and August 28, 2019. EWF has further attempted to schedule additional meetings with 

MT’s representatives, only to be repeatedly informed that MT could not be available. In addition 

to in person meetings, EWF has exchanged extensive written correspondence with MT as well as 

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participated in teleconferences. In the course of its discussions with MT, EWF has provided 

detailed technical explanations beyond that set forth in its claim charts, responded to repeated 

rounds of questions posed by MT representatives, as well as provided a detailed explanation for 

EWF’s proffered FRAND royalty rate.

37. However, to date MT has not reciprocated EWF’s good faith efforts, but has

instead resisted taking a license to the Patents in Suit. In particular, MT has plainly sought only 

to delay negotiations, such as by repeatedly rehashing technical issues already addressed, 

“sandbagging” EWF’s representatives with substantive materials mere days prior to scheduled 

meetings despite having several months to prepare such materials. Further, MT did not attempt 

to provide a counter-offer until August 2019, three years after negotiations with EWF began, and 

even then provided an unreasonably low offer that does not comport with FRAND. For at least 

the foregoing reasons, MT has failed to comply with its FRAND obligations to negotiate in good 

faith and without undue delay.

38. MT has further argued that it should be entitled to even more technical discussion 

than the detailed explanations provided to date, as well as unilaterally imposed requirements for 

details underlying the calculation of EWF’s FRAND rate, and that absent additional explanation 

EWF has not satisfied its FRAND obligations. 

39. On November 24, 2019, EWF sent correspondence reiterating its willingness to 

provide a license to MT on FRAND terms, including a lump sum offer. 

40. MT did not accept the November 24 offer. Instead, MT once again provided an 

unreasonably low offer, coupled with alleged technical “rebuttal” that largely rehashed prior 

arguments.

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41. Defendants MT and MTUS have been operating and continue to operate without a 

license to the Patents in Suit. Given Defendants’ unwillingness to engage in meaningful 

licensing discussions, to license the Patents in Suit, or otherwise to cease infringing the Patents 

in Suit, Plaintiffs NTT and EWF initiated this action for the purpose of protecting their patent 

rights in the United States. 

GENERAL ALLEGATIONS RELATING TO INFRINGEMENT

42. The Accused Products implement IEEE standard 802.11n and/or 802.11ac “WiFi” 

technology for wireless communication. The Accused Products include, but are not limited to: 

the MediaTek Helio A22; MT8163; MT8173/MT8173C; MT8321; MT8163B; MediaTek 8167S; 

MediaTek Helio P22T; RT3592; RT5370; RT5572; MT8125; MT8135; MT6735; as well as 

various similar products.

43. On information and belief, Defendant MT designs, makes, uses, imports, offers to 

sell, and sells (and/or has made, used, imported, offered to sell, and sold) in the United States and 

in this judicial district, Accused Products. 

44. On information and belief, Defendant MTUS uses, imports, sells, and/or offers to 

sell (or has used, imported, sold, and/or offered to sell) the Accused Products in the United States

and in this judicial district, including at the direction of MT.

45. Defendants have therefore infringed and continue to infringe one or more claims 

of the Patents in Suit under 35 U.S.C. § 271(a), including the claims set forth in the sections 

below, literally or under the doctrine of equivalents, by making, using, selling, and/or offering 

for sale in the United States, and/or importing into the United States, the Accused Products, 

without authorization.

46. Defendants have previous actual knowledge of the Patents in Suit, knew they

were identified by NTT in connection with the 802.11 standard, and knew of Plaintiffs’ 

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allegation of its infringement thereof no later than May 31, 2016, and therefore prior to the filing 

of this complaint.

47. On information and belief, Defendants have actively, knowingly, and 

intentionally induced and are inducing infringement of the Patents in Suit by selling, offering to 

sell and/or importing into the United States the Accused Products after being notified of their 

infringement by Plaintiffs; with the knowledge and specific intent that third parties, including its 

customers or downstream consumers, will continue to use, sell, offer for sale, and/or import the 

Accused Products or products incorporating the Accused Products to infringe the Patents in Suit; 

and with the knowledge and specific intent to encourage and facilitate the infringement through 

the dissemination of the Accused Products and/or the creation and dissemination of promotional 

and marketing materials, supporting materials, instructions, product manuals, and/or technical 

information and/or provision of technical support relating to the Accused Products and infringing 

uses thereof.

48. Defendants’ acts of direct and indirect infringement have independently and 

collectively caused damage to Plaintiffs, and Plaintiffs are entitled to recover from Defendants

the damages they have sustained as a result of Defendants’ wrongful acts in an amount subject to 

proof at trial.

49. Defendants have actively and knowingly infringed and are infringing the Patents 

in Suit with knowledge of Plaintiffs’ patent rights and without reasonable basis for believing that 

Defendants’ conduct is lawful. Defendants’ acts of infringement have been and continue to be 

willful, deliberate, and in reckless disregard of Plaintiffs’ patent rights.

50. In the interest of providing detailed averments of infringement, Plaintiffs provide 

below as to each of the Patents in Suit at least one exemplary claim to demonstrate infringement

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by the Accused Products. However, the selection of claims and Accused Products are merely 

exemplary, and should not be considered limiting. Additional infringing products and infringed 

claims of the Patents in Suit will be disclosed in compliance with the Court’s rules and 

scheduling order. 

COUNT I: INFRINGEMENT OF THE ’551 PATENT

51. The foregoing paragraphs are incorporated by reference as if fully restated herein.

52. The Accused Products are devices that implement “carrier sense multiple access” 

(“CSMA”) functionality in accordance with at least IEEE standard 802.11n and/or 802.11ac, and 

in accordance with at least claims 1 and 5 of the ’551 Patent. The CSMA functionality allows a 

transmitting station to determine whether a channel for transmission is in a busy or idle state.

53. The ’551 Patent is valid and enforceable. The ’551 Patent relates to apparatuses 

and methods for transmitting wireless communication, including transmitting a plurality of 

wireless packets simultaneously under conditions where multiple channels and/or MIMO 

capability are present. 

54. With respect to claim 1, the Accused Products set a mandatory channel that is 

always used for transmission. For example, the 802.11n standard defines a distinct “primary 

channel” and “secondary channel.” E.g., 802.11n-2009, 3.240, 3A.61, 11.14. The primary 

channel is always used for transmission. See e.g., 802.11n-2009, 11.14.2, 11.14.9. The 

secondary channel is not always used for transmission. Id.

55. The Accused Products further transmit wireless packets by using a wireless 

channel/wireless channels that includes/include the mandatory channel, only when the 

mandatory channel is idle. For example, the 802.11n standard requires a transmitting station to 

first sense whether the primary channel is idle. E.g., 802.11n-2009, 11.14.9. If the primary 

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channel is idle, transmission may occur over the primary channel, or both the primary and 

secondary channels. See e.g. 3A.29, 3A.34, 11.14.2, 11.14.9, 20.3.7, 20.3.11.11.

56. With respect to claim 5, because the Accused Products implement at least the 

functionality provided by the 802.11n standard set forth above, they include a unit for setting a 

mandatory channel, and transmitting wireless packets only when the mandatory channel is idle 

by using a wireless channel or wireless channels that includes/include the mandatory channel. 

57. Thus, for at least the reasons described above, the Accused Products infringe one 

or more claims of the ’551 Patent, including claims 1 and 5.

58. Defendants have and continue to directly and indirectly infringe the ’551 Patent, 

including in the manner set forth in paragraphs 42-49 above. 

COUNT II: INFRINGEMENT OF THE ’781 PATENT

59. The foregoing paragraphs are incorporated by reference as if fully restated herein.

60. The Accused Products are wireless packet communication devices that implement 

“carrier sense” functionality in accordance with at least IEEE standard 802.11n and/or 802.11ac, 

and in accordance with at least claim 1 of the ’781 Patent.

61. The ’781 Patent is valid and enforceable. The ’781 Patent relates to apparatuses 

and methods for wireless communication, and in particular transmitting a plurality of wireless 

packets simultaneously where multiple wireless channels may be available. 

62. With respect to claim 1, the Accused Products provide a physical carrier sense 

determining a wireless channel to be busy or idle from received power. For example, the 

802.11n standard provides for a PHY-CCA that indicates the channel as BUSY in response to 

received power. See e.g., 802.11n-2009, 20.3.22.5.2. 

63. The Accused Products further provide a virtual carrier sense determining a 

wireless channel to be busy during a set transmission inhibition time. For example, 802.11 

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provides for a NAV mechanism, which is a virtual carrier sense mechanism. See e.g., 802.11-

2007, 9.2.1. The NAV includes a value that reflects the duration of the longest transmission sent 

on a channel. See id. 

64. The Accused Products further include a transmit-side station (STA) that sets a 

transmission inhibition time (Tmax + Ts) to a paired wireless channel other than a wireless 

channel which requires longest transmission time Tmax among wireless channels used for 

simultaneous transmission, when an existing set transmission inhibition time for the virtual 

carrier sense is smaller than the time (Tmax+Ts). For example, the 802.11n standard provides 

that a transmitting STA may transmit 40 MHz PPDUs or 20 MHz PPDUs during a transmit 

opportunity. See e.g., 802.11n-2009, 11.14.9. A transmission inhibition time applies to the

secondary channel based on a value used in a virtual carrier sense, or NAV vector. In an 

exemplary scenario, the time Tmax may include to the longest transmission duration of a PPDU, 

while Ts may include a predetermined duration, such as a duration based on SIFS intervals. See 

e.g., 802.11-2007, 9.2.5.4.

65. Thus, for at least the reasons described above, the Accused Products infringe one 

or more claims of the ’781 Patent, including claim 1.

66. Defendants have and continue to directly and indirectly infringe the ’781 Patent, 

including in the manner set forth in paragraphs 42-49 above. 

COUNT III: INFRINGEMENT OF THE ’616 PATENT

67. The foregoing paragraphs are incorporated by reference as if fully restated herein.

68. The Accused Devices are OFDM signal transmitting devices that implement 

“block acknowledgment” functionality in accordance with at least IEEE standard 802.11n and/or 

802.11ac, and in accordance with at least claim 1 of the ’616 Patent.

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69. The ’616 Patent is valid and enforceable. The ’616 Patent relates to apparatuses 

and methods for wireless communication, and in particular to communication of a plurality of 

packets wherein transmission of data may use MIMO techniques.

70. With respect to claim 1, the Accused Products include predetermined sequence 

numbers in a plurality of data packets, the predetermined sequence numbers being for 

distinguishing said plurality of packets from each other. For example, the 802.11n standard 

defines sequence numbers provided in a sequence number field, and fragment numbers provided 

in a fragment number field. See e.g., 802.11n, 7.1.3.4.1-2.

71. Further, the Accused Products generate a single acknowledgement (“ACK”) 

packet which has received a plurality of data packets transmitted using MIMO and transmit the 

single ACK packet to a transmit-side STA without using MIMO. For example, the 802.11n 

standard requires implementation of a “BlockAck” feature, which, for example, would not be a 

MIMO transmission when carried in a non-HT PPDU or in communications with legacy devices. 

See e.g., 802.11n-2009, 9.10.1-2, 9.6.0e.4. Further, a BlockAck packet contains information that 

corresponds to a sequence number of a data packet successfully received. See e.g., 802.11-2007, 

7.2.1.8.

72. Thus, for at least the reasons described above, the Accused Products infringe one 

or more claims of the ’616 Patent, including claim 1.

73. Defendants have and continue to directly and indirectly infringe the ’616 Patent, 

including in the manner set forth in paragraphs 42-49 above. 

COUNT IV: INFRINGEMENT OF THE ’720 PATENT

74. The foregoing paragraphs are incorporated by reference as if fully restated herein.

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75. The Accused Products are OFDM signal transmitting and receiving devices that 

implement “beamforming” functionality in accordance with at least IEEE standard 802.11n 

and/or 802.11ac, and in accordance with at least claim 18 of the ’720 Patent.

76. The ’720 Patent is valid and enforceable. The ’720 Patent relates to methods, 

systems and devices for transmitting and receiving OFDM signals. In particular, certain 

embodiments involve devices comprising multiple receiving and/or transmitting antennas.

77. With respect to claim 18, the Accused Products comprise an OFDM signal 

transmitting device used in an OFDM signal communication system for transmitting signals over 

the same radio frequency from the OFDM signal transmitting device comprising a plurality of N 

transmitting antennas to an OFDM signal device comprising N receiving antennas. For example, 

the 802.11n standard provides for OFDM transmission over multiple antennas (MIMO). As a 

further example, the 802.11ac-2013 standard provides for Very High Throughput (“VHT”) 

transmission using beamforming for SU-MIMO or MU-MIMO. 

78. The Accused Products comprise an interference canceller, among an inverse 

matrix computer, the interference canceller, and a pilot signal generator. For example, the 

802.11n standard utilizes an inverse matrix computer to compute a steering matrix Qk to account 

for each channel and Gaussian noise. See e.g., 802.11n-2009, 20.3.12. Further, PLCP training 

fields are provided by a pilot signal generator. Id. at 20.3.4. Similarly, the 802.11ac standard 

provides that SU-MIMO and MU-MIMO beamforming utilizes a steering matrix Qk determined 

from the beamforming feedback matrix Vk. 802.11ac-2013, 22.3.11. One or more training fields 

in the VHT PPDU are generated by a pilot signal generator. See id. at 22.3.2, 22.3.8.3.4. 

79. Further, the inverse matrix computer of the Accused Products computes each of 

inverse matrices of N-dimensional square matrices for each subcarrier constituted by the 

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propagation coefficients for the respective propagation paths. For example, 802.11n provides 

that the steering matrix Qk is comprised of Ntx rows and Nsts columns, where Ntx represents the 

number of transmit chains, and Nsts represents the number of space-time streams. See 802.11n2009, 20.3.12. The computation is based on channel estimation, including propagation path 

measurements. See e.g., id. at 203.12.2. The steering matrix provided by 802.11ac operates 

similarly. See e.g., 802.11ac-2013, 9.29.1-3, 22.3.11. Upon information and belief, details 

concerning the use of inversion, or equivalents thereof, are implemented in software and/or 

source code for the Accused Products and may be verified through discovery.

80. Further, the interference canceller of the Accused Products cancels interference 

components based on the inverse matrix computed by the inverse matrix computer. For 

example, after computing the steering matrix Qk, the beamformer provided by 802.11n utilizes 

an interference canceller to replace the transmitted vector xk with Qkxk, such that yk = HkQkxk + 

n. See e.g., 802.11n-2009, 20.3.12. A similar method is provided by 802.11ac. 

81. The pilot signal generator of the Accused Products generates N kinds of pilot 

signals for use by the inverse matrix computer to compute the inverse matrix. For example, the 

802.11n standard provides for PLCP preamble training fields provided by a pilot signal 

generator. See e.g, 802.11n-2009, 20.3.4.a. The 802.11ac standard’s training fields are similarly 

generated by a pilot signal generator. See e.g., 802.11ac-2013, 22.3.2. 

82. The Accused Products comprise a data converter for respectively converting the 

transmission information signals of N systems into OFDM symbols. For example, the 802.11n 

standard provides that the stream parser and constellation mapper convert data into OFDM 

symbols. See e.g., 802.11n-2009, 20.3.11.7. A similar process is provided by 802.11ac. See 

e.g., 802.11ac-2013, 22.3.3. 

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83. The Accused Products further comprise an interference canceller, as discussed 

above, for multiplying the respective subcarriers of the respective OFDM symbols generated by 

the data converter. 

84. The Accused Products comprise inverse fast Fourier transformer circuitry for 

performing inverse Fourier transformation on the outputs from the interference canceller. See 

e.g., 802.11n-2009, 20.3.9.4.6; 802.11ac-2013, 22.3.3.

85. The Accused Products comprise transmission frequency converters for converting 

the frequency band of the output from the inverse fast Fourier transformers into radio frequency. 

See e.g., 802.11n-2009, 20.3.4.t; 802.11ac-2013, 22.3.4.2. 

86. Thus, for at least the reasons described above, the Accused Products infringe one 

or more claims of the ’720 Patent, including claim 18.

87. Defendants have and continue to directly and indirectly infringe the ’720 Patent, 

including in the manner set forth in paragraphs 42-49 above. 

COUNT V: PLAINTIFFS’ FRAND COMPLIANCE

88. The foregoing paragraphs are incorporated by reference as if fully restated herein.

89. As described above, NTT is a successful contributor to the 802.11 standards. 

Based on those contributions, NTT voluntarily committed to the IEEE to offer licenses to NTT’s 

standards essential patents related to various 802.11 standards, including the Patents in Suit. 

90. Because of Defendants’ unlicensed practice of the Patents in Suit, EWF, as the 

exclusive licensee of the Patents in Suit, offered to engage in good faith negotiations with 

Defendants to meet NTT’s obligations to the IEEE. Pursuant to IEEE policy, EWF has been, 

and remains, prepared to grant Defendants a license to the Patents in Suit on terms that are 

FRAND. 

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91. However, Defendants are unwilling licensees. As described above, Defendants 

have refused to negotiate a license in good faith and have repeatedly sought to delay negotiations 

by rehashing issues already addressed on multiple occasions. In particular, Defendants have 

explicitly argued that EWF has not discharged its duty to provide an explanation of infringement 

required by its FRAND obligations. 

92. There is a dispute between Plaintiffs and Defendants regarding whether EWF’s 

actions and offers to Defendants for a license to the Patents in Suit complied with NTT’s 

commitment to be prepared to grant a license to its standard essential patents on terms and 

conditions consistent with the IEEE’s IPR policy and any applicable laws. 

93. Plaintiffs request that the Court declare that (a) Plaintiffs have complied with their 

obligations under NTT’s FRAND commitment; and (b) the terms and conditions offered by 

Plaintiffs regarding a license to the Patents in Suit are consistent with NTT’s FRAND

commitment.

JURY DEMAND

Plaintiffs demand a trial by jury on all triable issues in this action.

PRAYER FOR RELIEF

WHEREFORE, Plaintiffs respectfully request the following relief:

A. A judgment that the Patents-in-Suit are valid and enforceable;

B. A judgment that Defendants have directly infringed, contributorily infringed, and 

induced infringement of the Patents-in-Suit; 

C. An order awarding Plaintiffs statutory damages and damages according to proof 

resulting from Defendants’ infringement of the Patents-in-Suit, together with prejudgment and 

post-judgment interest and costs under 35 U.S.C. § 284;

Case 6:20-cv-00225-ADA Document 1 Filed 03/25/20 Page 18 of 19
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D. An order trebling or otherwise enhancing damages under 35 U.S.C. § 284 in view 

of the willful and deliberate nature of Defendants’ infringement of the Patents-in-Suit;

E. A judgment that this is an exceptional case under 35 U.S.C. § 285 and that 

Plaintiffs be awarded its costs and attorneys’ fees; 

F. A judgment that that Plaintiffs have complied with NTT’s FRAND commitment 

in negotiations with Defendants;

G. A judgment that the terms and conditions offered by EWF, as NTT’s exclusive 

licensee, to Defendants regarding the Patents in Suit are consistent with NTT’s FRAND 

commitment; or, in the alternative, to declare the terms and conditions necessary to meet NTT’s

FRAND commitment;

H. A judgment that Defendants are unwilling licensees to the Patents in Suit; and

I. Any and all other relief as may be available under law and which the Court may 

deem proper.

Dated: March 25, 2020 Respectfully submitted,

DICKINSON WRIGHT PLLC

By: /s/ Steven R. Daniels

Steven R. Daniels, Texas Bar No. 24025318

Jia-Geng Lu, Texas Bar No. 24081010

607 W. 3rd Street, Suite 2500

Austin, Texas 78701

Telephone: (512) 770-4200

Facsimile: (844) 670-6009

SDaniels@dickinsonwright.com

JLu@dickinsonwright.com

Attorneys for Plaintiffs

Nippon Telegraph and Telephone Corporation

and Essential WiFi, LLC

Case 6:20-cv-00225-ADA Document 1 Filed 03/25/20 Page 19 of 19