US 7177369

I'll search for authoritative information on this patent number and its litigation/docket status.

Let me check for Federal Circuit appeal activity and current litigation status.

Let me check the most recent 2025–2026 activity and the independent claim text.

US Patent 7,177,369 — Summary and Status

Note on identifiers: I interpreted "7177369" literally as US 7,177,369 B2. All bibliographic facts below are taken from the authoritative full text you supplied plus live search results; where sources disagree I say so explicitly.

1. Bibliographic Data

Uncertainty flag — dates: The one-day discrepancies (priority, filing, grant, expiration) recur across aggregators and are most likely time-zone/reporting artifacts rather than substantive differences. The Google Patents record (filing 2002‑04‑25; priority 2001‑04‑27; issue 2007‑02‑13) is consistent with the patent's own front page text ("Filed: Apr. 25, 2002"; "Date of Patent: Feb. 13, 2007") and with the E.D. Tex. AO‑120 form, which lists the '369 patent as dated 2/13/2007.

Assignee chain (from Google Patents reassignment records):
Mabuhay Networks, Inc. (2002 assignment / 2003 name change) → Vivato, Inc. → Wayout Wireless, LLC (2006) → Vivato Networks, LLC (2007) → Vivato Networks Holdings, LLC (2007) → Aequitas Equipment Finance, LLC (2009, via foreclosure/judicial sale) → XR Communications, LLC (assigned 2009‑12‑23).

2. Abstract

"Methods, apparatuses and systems are provided for identifying at least one multipath transmission delay within a reverse path data signal, determining at least one forward path pre-equalization parameter based on the transmission delay, and modifying a forward path data signal based on the forward path pre-equalization parameter. A reverse link transmission is used to help characterize the multipath delays that may exist between communicating devices. The reverse path data signal can include a training sequence or other like known/substantially-known data that can be analyzed to detect transmission delays, especially delays that extend beyond established guard intervals. Such pre-equalization techniques can be advantageously combined, for example, with antenna arrangements that support transmission diversity, spatial division transmission, and/or other like techniques."

3. Plain-Language Overview of the Independent Claims

The specification describes a base station (102) that pre-equalizes signals it transmits to a CPE device (104). The trick is reciprocity: because the forward and reverse channels are assumed reciprocal (e.g., in TDD, coherent for roughly 10 ms), the base station can characterize multipath delays by analyzing a known training sequence in a reverse-path signal from the CPE, derive correction parameters, and apply them to the forward-path signal — including corrections for delays that exceed the OFDM guard interval (GI). This shifts equalization complexity to the base station and away from the receiver.

Claim 1 (method) — the only independent claim I have verbatim:

• Identifying at least one multipath transmission delay within a reverse path data signal received from a receiving device;
• Determining at least one forward path pre-equalization parameter based on that transmission delay; and
• Modifying a forward path data signal intended for that receiving device based on the parameter,
• where the modifying includes selectively setting different transmission power levels for at least two OFDM tones in the forward path data signal.

The last clause is the notable narrowing point: this independent claim is tied to per-tone transmit-power differentiation, not merely to phase/amplitude pre-equalization generally.

Claim 42 (system) — inferred from its dependents, not quoted verbatim:
From dependent claims 43–78 (retrieved via Justia), claim 42 appears to recite a system with a first device (base station-type: transceiver(s), at least one antenna, logic) and a second device (CPE-type: antenna, transceiver, logic), where the logic is configured to identify a multipath transmission delay in a reverse-path data signal from the second device, determine a forward-path pre-equalization parameter, and modify the forward-path signal accordingly. Dependent claims add: post-equalization of the received reverse path (58), angle-of-arrival determination (59), OFDMA reverse data (61), reverse bit rate < about 6 Mbps (62), CPE power-level feedback driving forward-path power adjustment (63), transmit diversity (64), spatial-division/narrow-beam transmission (65), antenna pointing and phased-array directing parameters (69–70), single-angle transmission (71), antenna selection (72), multiple phase/amplitude-adjusted beams (73–74), and iterative testing of different pre-equalization parameters to resolve aliased multipath delays (77).

Claim 79 (apparatus) — partially retrieved:
Begins: "An apparatus comprising: an Orthogonal Frequency Division Multiplexing (OFDM) processor configured to receive coded data and output corresponding OFDM data; a pre-equalizer operatively coupled to said OFDM processor and configured…" — i.e., a transmitting-side apparatus pairing an OFDM processor with a pre-equalizer. I could not retrieve the full text of claim 79 or any independent claims beyond 1, 42, and 79.

Uncertainty flag — independent claims: The patent has 91 claims. The IPR petition by Ericsson/Nokia challenged claims 1–7, 9, 10, 12–15, 19, 21, 28, 32, 33, 35–37, and 41 (i.e., the claim set breaks around claims 8/9 and 41/42), consistent with claim 1 and claim 42 being independent, and claim 79 starting a further independent apparatus claim. I cannot rule out one or more additional independent claims in the 9–41 or 80–91 ranges; I do not have verbatim text for those and will not guess at them.

4. Litigation, PTAB, and Any CAFC Docket Activity

District court (E.D. Tex.)

• XR Communications LLC d/b/a Vivato Technologies v. AT&T Inc. et al., No. 2:23‑cv‑00202 (E.D. Tex., filed May 8, 2023), consolidated lead case with member cases 2:23‑cv‑00203 (AT&T) and 2:23‑cv‑00204 (T‑Mobile); related cases 2:23‑cv‑00468/00469/00470. The '369 patent was one of five asserted (with 8,737,511; 10,715,235; 10,594,376; 8,289,939), per the AO‑120 filing.
• The "pre-equalization parameter" term was a disputed construction; Defendants argued XR's proposed "to reduce unwanted effects associated with multipath fading" language improperly imported an intent limitation (Dkt. 86, filed 8/12/2024).
• Outcome: settled, then dismissed. A joint motion to stay deadlines and notice of settlement was filed 10/27/2025 (Dkt. 293), granted 10/28/2025. On January 8, 2026, Judge Rodney Gilstrap entered an order dismissing all claims with prejudice (counterclaims without prejudice) — Dkt. 300.
• A second, later E.D. Tex. docket involving XR (No. 2:25‑cv‑00979) appears in the Google Patents litigation list and the Stanford NPE database. I was not able to retrieve details of that case (defendant, whether '369 is asserted) before hitting the search limit — treat as unverified.
• One search result shows a further dismissal order in the consolidated member cases (2:23‑cv‑00468/469/470) signed July 13, 2026. Flag: that document post-dates the "current date" you supplied (April 26, 2026), which indicates the search index is not date-limited to that day; I report the date as retrieved.

PTAB

• Ericsson Inc. et al. v. XR Communications LLC, IPR2024‑00314, filed January 5, 2024, on U.S. 7,177,369 / App. 10/131,864 (Tech Center 2600). Challenged claims 1–7, 9, 10, 12–15, 19, 21, 28, 32, 33, 35–37, 41 under §103.
• Institution denied (July 15, 2024) — Google Patents labels it "Not Instituted – Merits." The Board construed "pre‑equalization parameter" sua sponte, and Petitioners filed a Request for Director Review on August 14, 2024 arguing (1) they were not heard on the sua sponte construction and (2) the construction was improperly narrow.

Federal Circuit (2026)

• I found no Federal Circuit docket in 2026 — or any year — involving US 7,177,369. No CAFC appeal of the E.D. Tex. cases appears; those cases were resolved by settlement and dismissal, not judgment.
• The only XR/Vivato Federal Circuit activity surfaced concerns different patents — e.g., an XR/Vivato notice of appeal (May 9, 2022) from a C.D. Cal. final judgment on the '231 patent, and related Case No. 22‑1125 at the Federal Circuit. Nothing ties those appeals to 7,177,369.

5. Bottom Line

US 7,177,369 claims base-station-side pre-equalization of a forward OFDM link using reciprocal reverse-link channel measurements, explicitly aimed at multipath delay spread longer than the guard interval, with claim 1 additionally requiring per-tone transmit-power differentiation. It is expired (adjusted expiration July 2024). Its most recent enforcement effort (E.D. Tex., 2023–2025, against AT&T/Verizon/T‑Mobile with Ericsson and Nokia intervening) settled and was dismissed with prejudice on January 8, 2026; the parallel IPR (IPR2024‑00314) was denied institution, with a Director Review request pending as of August 2024. I could not verify any CAFC 2026 docket for this patent, and I could not retrieve the verbatim text of independent claims 42 and 79.

I'll research litigation involving US patent 7177369 across patent litigation databases.

Let me dig deeper into the specific cases and their current status.

Litigation Involving U.S. Patent No. 7,177,369

I located the patent on Google Patents and cross-checked its litigation links against the Unified Patents portal, CourtListener/recap dockets, the Stanford NPE Litigation Database, PTAB records, and PACER-based aggregators. Note: I interpreted the number 7,177,369 literally and excluded results for other Vivato/XR patents (e.g., 6,611,231; 7,062,296; 8,737,511; 8,289,939; 10,594,376; 10,715,235; 11,750,256; 11,777,569) that appear in XR's broader campaigns but are not this patent.

District court litigation

Details and sources

2023 consolidated cases (2:23-cv-00202 / -00203 / -00204). The USPTO "Report on the Filing of an Action" (AO 120) confirms the ’369 patent was one of five patents asserted against AT&T, listing "7,177,369 – 2/13/2007 – XR Communications, LLC." (Source: ptacts.uspto.gov AO 120 filing.) The cases were consolidated with -00202 as lead. XR's final election of asserted claims identified U.S. 7,177,369 claims 1, 32, 36, 41 (Doc. 258, dated 9/5/2025). The ’369 patent was also the subject of a partial summary-judgment motion of no literal infringement (Doc. 160) and a Report & Recommendation (Doc. 267). After mediation before David Folsom (settlement reported 11/4/2025), the parties filed a joint motion to dismiss; Judge Rodney Gilstrap dismissed the cases with prejudice on 1/8/2026 (Doc. 299), with defense counterclaims dismissed without prejudice. (Sources: CourtListener docket 67349582; storage.courtlistener.com recap PDFs for txed.222063, Docs. 258, 299; unifiedpatents.com litigation links.)

2:25-cv-00979 (XR Communications v. Nokia of America Corp). A newer E.D. Tex. action in which the ’369 patent is among the asserted patents; the complaint targets Nokia's 5G NR RAN solutions supporting 3GPP 5G NR beamforming and alleges they perform the claimed reverse-path multipath-analysis / forward-path pre-equalization method. Status listed as Open. (Source: ai-lab.exparte.com/case/dct/txed/2:25-cv-00979; Google Patents family-litigation link.)

Caveat: A related 2025 E.D. Tex. case, XR Communications LLC v. Verizon Communications, Inc. et al., 2:25-cv-00698, was also located in PACER-based results, but I could not confirm from the retrieved records that the ’369 patent is asserted there (XR's 2025 assertions appear to center on the ’511/’235/’376/’939 family). Treat any ’369 link to -00698 as unverified.

PTAB (inter partes review)

The Board denied institution of IPR2024-00314 on the ’369 patent (institution decision date 7/15/2024). The panel adopted a sua sponte construction of "pre-equalization parameter," and Petitioners (Ericsson/Nokia) sought Director Review on 8/14/2024, arguing (1) they were not given an opportunity to be heard on the sua sponte construction (citing the Director's Slyde Analytics decision, IPR2024-00040), and (2) the construction was impermissibly narrow. (Sources: ipverse.greyb.com/case-details/IPR2024-00314; ptacts.uspto.gov petition documents; Google Patents litigation entry, which lists it as "Not Instituted – Merits.") Related PTAB activity involving the same consolidated district-court matters includes IPR2024-00868 (Ericsson v. XR Communications), but that filing's mandatory notices reference the district cases rather than confirming it targets the ’369 patent.

Summary

• Total known U.S. litigation asserting U.S. 7,177,369: four district-court actions (three 2023 E.D. Tex. cases against AT&T, Verizon, and T-Mobile, all consolidated and settled/dismissed with prejudice in January 2026, plus one 2025 E.D. Tex. case against Nokia of America Corp, still open), and one PTAB IPR (IPR2024-00314, institution denied).
• No appellate (CAFC) decision on the ’369 patent was found. The CAFC decisions in the XR/Vivato campaign that surfaced (e.g., XR Communications v. Arris Solutions, May 18, 2023) concern the ’231 patent, not the ’369 patent.
• The patent is listed as expired (adjusted expiration 7/13/2024), with current assignee XR Communications, LLC (Stanford NPE database classifies the asserter under "Failed startup" origins).

If you need the primary docket PDFs or the exact Director Review disposition (granted/denied) for IPR2024-00314, I can attempt a focused follow-up search on those specific documents.

I'll start by verifying the one proceeding flagged in the prior sections against the canonical ODP block, and probe for any others.

Now let me pull the substance of the institution decision and check whether any other IPR targets this patent.

Let me pin down the Director Review disposition and confirm there's no Federal Circuit appeal.

Proceedings overview

One AIA trial proceeding exists on US 7,177,369 — IPR2024-00314 — and it ended in a DENIED INSTITUTION (2024-07-15), with Director Review denied; 0 claims canceled, 0 claims sustained on the merits, no Final Written Decision, no IPR settlement. The bottom line for a defendant today is nuanced: the patent is not "hardened" by any merits adjudication — it has never been tested on the merits at the PTAB, so no statutory estoppel attaches and every claim remains live — but the Board's threshold reasoning bequeathed defendants a narrow construction of "pre-equalization parameter" that the patent owner itself adopted in district court, so the practical defensive posture is modestly favorable even though the procedural record is a patent-owner win.

⚠️ Contradiction to flag. The structured "PTAB proceedings on file" block in this prompt states the USPTO ODP API returns no AIA trials for this patent. That is wrong as of the records I retrieved. IPR2024-00314 is real: the petition, the institution-denial decision (Paper 12), the Petitioner Request for Director Review (Paper 13), the Director's denial order, and the post-institution fee-refund request are all in the PTAB file at ptacts.uspto.gov (petition ID 1555050). A parallel artifact of that ODP gap: the one AIA proceeding touching this patent is not the one previously surfaced in these materials as "IPR2024-00868" — that proceeding is on U.S. 8,737,511, a different XR Communications patent. There is exactly one IPR on the '369.

IPR2024-00314 — Ericsson Inc. and Nokia of America Corporation v. XR Communications LLC

• Type: Inter Partes Review
• Filed: 2024-01-05 (Patent 7,177,369 B2; App. 10/131,864; Tech Center 2600)
• Status: Institution Denied (canonical data: IP Verse/GreyB "Institution Denied"; Google Patents: "Not Instituted — Merits"; institution decision 2024-07-15, Paper 12)
• Judge panel: Not confirmed. I could not retrieve the APJ names on the '369 institution panel from the public excerpts. (The panel names that surfaced in my searches — Strauss, Beamer, Szpondowski, Deshpande, Parvis, Mayberry — belong to IPR2024-00868 on the '511 patent and must not be attributed here.)
• Real parties-in-interest: Petitioners identified "Ericsson Inc., and corporate parent Telefonaktiebolaget LM Ericsson, and Nokia of America Corporation"; they additionally named T-Mobile USA, Inc., AT&T Services Inc., AT&T Mobility LLC, AT&T Corporation, and [Cellco Partnership d/b/a Verizon Wireless](/litigations/by-plaintiff/Cellco%20Partnership%20d%2Fb%2Fa%20Verizon%20Wireless) as RPIs because Petitioner's products supplied to those entities were accused of infringement in the co-pending E.D. Tex. matters. Patent Owner: "XR Communications LLC d/b/a Vivato Technologies."
• Petition grounds: §103 only. Challenged claims 1–7, 9, 10, 12–15, 19, 21, 28, 32, 33, 35–37, and 41. The petition's theory was that the '369 patent claims "the admittedly well[-]known concept of reciprocity combined with an (also well-known) concept of…" forward-path adjustment; the primary references were Wong (Ex. 1005 — multiuser OFDM adaptive subcarrier/bit/power allocation) and Minn (time-domain OFDM channel estimation with "most significant taps" selection). Expert: Dr. Kevin Negus (Ex. 1003).
• Institution decision — DENIED, 2024-07-15 (Paper 12): The panel sua sponte construed "pre-equalization parameter" and held that, "at a minimum, pre-equalization requires 'accounting for properties of a propagation path.'" On that construction, Petitioner's showing — Wong's "channel gain magnitude" used in a TDD power-minimization algorithm — did not establish a reasonable likelihood as to claim 1's elements [1.1]/[1.2]. The Board expressly noted Patent Owner did not dispute that Wong teaches or suggests a multipath transmission delay, so it did not reach Minn on limitation [1.0]. Because every challenged claim depends from claim 1, denial on claim 1 disposed of the entire petition: "For the reasons set forth below, we do not institute an inter partes review."
• Final Written Decision: None — trial was never instituted, so there is no claim-level verdict to report. Neither independent nor dependent claims were canceled or confirmed.
• Settlement / termination: The IPR itself did not settle; it terminated at the institution stage. The parallel district court litigation later settled and was dismissed with prejudice on 2026-01-08 (E.D. Tex. 2:23-cv-00202/-00203/-00204), but that is a district-court event, not a PTAB termination.
• Appeal: No Federal Circuit appeal — and none was legally available. A denial of institution is not appealable (35 U.S.C. § 314(d); Cuozzo). Instead, Petitioners filed a Request for Director Review on 2024-08-14 (Paper 13), raising two issues: (1) the panel decided on a sua sponte construction without affording the parties an opportunity to be heard, in conflict with the Director's decision in Samsung v. Slyde Analytics, IPR2024-00040, and cases such as Qualcomm Inc. v. Intel Corp.; and (2) the construction was impermissibly narrow (crafting a new limitation, excluding the specification embodiments). Petitioners stressed that "the panel's construction was the sole basis of denying Institution." Director Review was DENIED by an order signed "Before KATHERINE K. VIDAL" — the order's exact date is not confirmed in the excerpts I retrieved (flag). Petitioners separately filed a Request for Refund of Post-Institution Fees on 2024-09-12, confirming no trial ever started.
• Defensive value: Mixed. The denial is not a merits loss for the patent — no claim was adjudicated and no §315(e) estoppel attaches — so a fresh petitioner is unconstrained. But the Board's reasoning is usable ammunition: the panel read "pre-equalization" to require "accounting for properties of a propagation path," and XR then embraced a parity construction in the district court ("modifying a signal to reduce unwanted effects associated with multipath fading between the transmitter and the receiver") to defeat Defendants' broader reading. Either way, claim 1 is not built for a broad infringement theory — pre-equalization must be a real, path-characterizing step tied to the multipath delay, not merely "any parameter that sets tone power levels."

Strategic summary

Claim status. Nothing on this patent is canceled, and nothing is sustained on the merits — the sole IPR died at the §314 threshold. Accordingly, all 91 claims are UNTESTED at the PTAB, including the full challenged set (1–7, 9, 10, 12–15, 19, 21, 28, 32, 33, 35–37, 41). The record in the IPR papers and the district court filings states that claim 1 is the sole independent claim and all other claims depend from it (XR's POPR and the Board's decision). Flag: this contradicts the earlier "Patent summary" section in these materials, which inferred independent system claim 42 and apparatus claim 79. I could not fully reconcile the two; the PTAB/district record ("sole independent claim") is the better-sourced statement, and XR's elected asserted claims ('369 claims 1, 32, 36, 41 — all dependents of claim 1) are consistent with it. Treat the "multiple independent claims" inference as unverified.

Estoppel landscape. §311/§315 estoppel is a function of institution and FWD. There was no institution, so §315(e)(1)/(2) estoppel has not attached to Ericsson, Nokia, or their privies. Grounds that were raised, and grounds that "reasonably could have been raised," remain available to them and to any other challenger — subject only to §315(b)'s one-year bar (from service of a complaint alleging infringement) and to the practical reality that the patent expired 2024-07-13. A new defendant is therefore not estopped by anything the '369 IPR did, and the prior denial created no res judicata.

Pattern signals. The same petitioner pair (Ericsson + Nokia, Duane Morris LLP: Patrick McPherson / Kevin Anderson) filed two IPRs against this XR portfolio in 2024: this one on the '369 and IPR2024-00868 on the '511 patent. The contrast is instructive — IPR2024-00868 was instituted 2024-12-13 and produced a Final Written Decision on 2025-11-25 holding all challenged claims unpatentable, whereas the '369 petition was rejected at the doorstep on claim construction. So the petitioners' art-sets can win when the Board reaches the merits; they simply drew a bad panel outcome on the "pre-equalization" term here. There is no Unified Patents (or other defensive aggregator) IPR on the '369, and XR (counsel Russ, August & Kabat: Reza Mirzaie / Philip Wang) had no reason to appeal — it won at institution.

Recommended next steps

1. Do not represent that any claim of the '369 is canceled. There is no FWD to cite; the only "win" is a non-instituted petition. Cite instead the petition file at PTAB petition 1555050 (Paper 12, Decision Denying Institution, 2024-07-15) and the Director's denial of the Director-Review request (same petition ID; order signed by Director Vidal).
2. Weaponize the Board's construction. Quote the Panel's holding that pre-equalization requires "accounting for properties of a propagation path" (IPR2024-00314, Paper 12 at ~15, as reproduced in E.D. Tex. Dkt. 81/Ex. 12). This is the same construction XR pressed in the district court, so it is effectively adopted by the patent owner — a strong basis to argue claim 1's pre-equalization limitation is narrow and its "different transmission power levels for at least two OFDM tones" clause cannot be met by generic adaptive bit/power allocation (Petitioner's Wong theory, which the Board rejected anyway).
3. Monitor the remaining enforcement vehicle. The '369 is expired (adjusted expiration 2024-07-13), so any recovery is backward-looking, but the 2:25-cv-00979 (E.D. Tex., XR Communications v. Nokia of America Corp) matter surfaced in the prior sections as still open. Verify whether the '369 is in that case and, if so, whether the §315(b) one-year window has run against Nokia (it likely has, given Nokia's earlier RPI status in IPR2024-00314 and the 2023 service dates — a time bar argument, not an estoppel argument).
4. If you are contemplating your own IPR, remember there are no claimed-claim numbers to attack in the alternative, no prior FWD, and no §315(e) estoppel blocking you — but the §315(b) one-year clock and the expired-patent posture should drive the cost/benefit analysis. If you file, build the petition around the Board's own threshold construction, since that is the construction the proceeding will be measured against.

Caveats on sourcing: the panel composition for IPR2024-00314 and the precise date of the Director's denial order are unconfirmed from the materials I retrieved; I have not asserted them. Everything else above (filing date, challenged claims, 2024-07-15 denial, the construction, the 2024-08-14 Director-Review request, and the 2024-09-12 refund request) traces to the PTAB file and to CourtListener exhibits of the Board's decision.

I'll research the assignment record for US 7,177,369, including reel/frame data and correspondents of record.

I found the reel/frame chain in a PTAB filing. Let me dig for the remaining links and correspondents.

I have most of the chain. Let me find the Aequitas→XR links and the correspondents of record.

Assignment Record Reconstruction — US 7,177,369 B2

Important methodological note. The USPTO Assignment Center (assignmentcenter.uspto.gov) and its legacy mirror (assignment.uspto.gov/patent/index.html) are behind interactive session queries and were not directly retrievable here. I reconstructed the chain from recorded reel/frame citations quoted verbatim inside USPTO PTAB filings and E.D. Tex. court exhibits, which restate the Assignment Center record. Every reel/frame below is a literal quote from those documents; I flag where a number was confirmed on a sibling Vivato patent's chain-of-title statement rather than on the '369 statement itself. I have not invented any reel/frame.

Inventors

Unusual-pattern check. With a single inventor, the classic "all inventors depart within 12 months" tell is not analyzable as stated. What is observable: the '369 inventor assigned at filing to a venture-backed startup that raised $80M+ (per XR's own complaint), and that startup's own portfolio was later sold at a secured-lender foreclosure within ~5 years of issue. I did not retrieve a dated record of Crilly's departure from Vivato, so I will not assert one.

Original assignee

Mabuhay Networks, Inc. → renamed Vivato, Inc. (Change of Name, 2003) → Vivato Networks (2007). Google Patents lists "Original Assignee: Vivato Inc"; Unified Patents lists the same.

• Product line / business. Vivato was an operating company, not a paper entity: it built phased-array Wi‑Fi base stations (the "Vivato Switch"/panel) targeting extended-range 802.11 coverage. Contemporaneous third-party evaluation material (FSU OTC Vivato Switch Evaluation) documents real campus deployments, and XR's complaint claims "over 400 deployments globally." So at least early on, Vivato shipped hardware arguably reading on the beamforming/antenna claims.
• Current status. Dissolved / liquidated. Vivato Networks merged with Catcher Holdings, Inc. in Dec 2007; Catcher ceased operations and terminated all employees 2008‑04‑01 for lack of working capital (E.D. Tex., Dkt. 60 ¶95). The portfolio was then foreclosed, taken by sheriff's sale, and sold. The Vivato name survives only as a d/b/a of XR Communications ("XR Communications, LLC d/b/a Vivato Technologies"), not as an operating business.

Assignment timeline

Chronological, reconstructed from the chain-of-title statement filed in IPR2024‑00314 (USPTO PTAB petition document, chain under 37 CFR 3.73), the companion chain statement filed on the sibling Forced Beam Switching patent, and the E.D. Tex. exhibits reproducing the recorded documents. Dates are recordation-side dates as surfaced by Google Patents legal events unless otherwise noted.

• 2002‑04‑25 (filed same day) — Reel 012849 / 0727

  • Conveyance: Assignment (inventor → company)
  • Assignor: Crilly, William J., Jr.
  • Assignee: Mabuhay Networks, Inc.
  • Correspondent: not retrieved (pre-grant recordation; correspondent field not in the quoted excerpt).
  • Context: original employment/startup assignment executed at filing.

• 2003‑04‑11 — Reel 013937 / 0808

  • Conveyance: Change of Name only (no change of beneficial owner)
  • Assignor: Mabuhay Networks, Inc.
  • Assignee: Vivato, Inc.
  • Correspondent: not retrieved.
  • Context: internal corporate renaming.

• 2006‑09‑21 — Reel 018313 / 0508 (one quoted page) — or 018313 / 0608 (a second quoted page and a companion patent)

  • Conveyance: Assignment — "First Amendment to Asset Purchase Agreement"
  • Assignor: Vivato, Inc.
  • Assignee: Wayout Wireless, LLC
  • Correspondent: not retrieved.
  • Context: asset transfer to a new LLC — the first step away from the operating company. Flag: the reel is consistent (018313) but the frame is cited as 0508 in one part of the '369 petition and 0608 in another; treat the frame digit as provisional.

• 2007‑08‑06 — Reel 019704 / 0789

  • Conveyance: Change of Name
  • Assignor: Wayout Wireless, LLC
  • Assignee: Vivato Networks, LLC
  • Correspondent: not retrieved.
  • Context: internal renaming. (Reel confirmed on the sibling Vivato chain statement.)

• 2007‑11‑30 — Reel 022783 / 0433

  • Conveyance: Security Agreement (recorded to perfect a lien)
  • Assignor: Vivato Networks, Inc. (f/k/a Vivato Networks, LLC)
  • Assignee: Aequitas Capital Management, Inc. (security interest)
  • Correspondent: Carl J. Schwedler, Bullivant Houser Bailey — XR's/ERISA defendants' filings state Schwedler personally "filed the security agreement with the Patent Office in fall of 2007" and later "filed the foreclosure judgment with the Patent Office in summer of 2009." That is a repeat correspondent across two links of this chain (security → foreclosure).
  • Context: securitization — the $1,000,000 loan (initial advance $300,000) that ends in foreclosure.

• 2007‑12‑04 — Reel 020213 / 0950

  • Conveyance: Assignment (of interest) / corporate reorganization
  • Assignor: Vivato Networks, LLC (now known as Vivato Networks, Inc.)
  • Assignee: Vivato Networks Holdings, LLC
  • Correspondent: not retrieved.
  • Context: internal reorg executed the same month Vivato Networks merged with Catcher Holdings, Inc. (Reel confirmed on the sibling chain statement.)

• 2009‑05‑06 — Reel 022783 / 0433 (same reel as the security agreement)

  • Conveyance: Limited Judgment of Foreclosure (also a Loan Assignment and Acceptance recorded the same day)
  • Assignor: Vivato Networks, Inc.; separately Aequitas Capital Management, Inc.
  • Assignee: Aequitas Equipment Finance, LLC (Oregon LLC)
  • Correspondent: Carl J. Schwedler, Bullivant Houser Bailey.
  • Context: foreclosure/securitization wind-down — the secured lender converts its lien into title.

• 2009‑06‑05 — Reel 022783 / 0433

  • Conveyance: Sheriff's Certificate of Judicial Sale
  • Assignor: Vivato Networks Holdings, Inc. (formerly Vivato Networks Holdings, LLC)
  • Assignee: Aequitas Equipment Finance, LLC
  • Correspondent: Carl J. Schwedler.
  • Context: fire-sale completion — title passes to the lender's holding vehicle.

• 2009‑12‑23 — Reel 023691 / 0645

  • Conveyance: Assignment of Interest ("Assignment of Patent Rights")
  • Assignor: Aequitas Equipment Finance, LLC (Oregon LLC)
  • Assignee: XR Communications, LLC (Delaware LLC, Reg. No. 4761724; 2809 Ocean Front Walk, Venice, CA 90291)
  • Correspondent: Daniel P. Burke — address 240 Townsend Square, email dburke@dpburke.com (Daniel P. Burke & Associates; attorney docket 1959‑2). Burke is the same attorney who worked the XR–Aequitas Patent Purchase Agreement, is the recording correspondent, and later filed XR's revival petitions. He recurs across the XR-side links.
  • Context: transfer-to-asserter — the entire Vivato portfolio (Exhibit A‑1 expressly lists 10/131,864 → U.S. 7,177,369) sold to XR.

Reel/frame provenance. 012849/0727, 013937/0808, 018313/0508–0608 were quoted from the '369-specific chain statement. 019704/0789, 020213/0950, 022783/0433, 023691/0645 were quoted from the companion Vivato portfolio chain statement (same Aequitas→XR "Patent Rights" assignment, whose Exhibit A‑1 lists the '369). They are the correct portfolio-level records but I could not lay eyes on the '369 supplemental sheet itself, so I mark them high-confidence, one-step-removed.

No-record check: Assignment Center does have records for this patent — this is not a "no recorded post-issuance assignments" case.

Timeline diagram

timeline
    title Ownership of US 7177369
    2001 : Crilly files provisional 60287163
    2002 : Crilly assigns to Mabuhay Networks
         : Application 10131864 filed
    2003 : Mabuhay renamed Vivato Inc
    2006 : Vivato Inc transfers assets to Wayout Wireless
    2007 : Patent issues as US 7177369
         : Wayout renamed Vivato Networks LLC
         : Aequitas records security interest
         : Vivato Networks Holdings created
    2009 : Aequitas forecloses and takes title
         : Aequitas sells portfolio to XR Communications
    2023 : XR sues AT T Verizon T Mobile
    2024 : PTAB denies IPR institution
    2026 : Suits dismissed with prejudice

NPE / troll-pattern signals

1. Shell-entity transfer — PRESENT. The operating assignee (Vivato Networks) is stripped of the patent via foreclosure (Reel 022783/0433, 2009) and title lands in Aequitas Equipment Finance, LLC, a lender's holding vehicle, then in XR Communications, LLC (Reel 023691/0645, 2009‑12‑23). XR is a single-purpose Delaware LLC (Reg. No. 4761724) holding 17+ issued Vivato patents, whose only visible activity is patent assertion under the d/b/a "Vivato Technologies." Its listed principal place of business (2809 Ocean Front Walk, Venice, CA) is a residential-style beach address, not a manufacturing site. This is not inferred from the name — it is supported by the recorded conveyor sequence plus XR's own litigation conduct.

2. Known asserter in the chain — PRESENT. XR Communications LLC is indexed as an asserter in the Stanford NPE Litigation Database (npe.law.stanford.edu/patent/7177369, "Asserter Categories: Failed startup") and appears in Unified Patents' patent/litigation portal. It is a serial filer (D‑Link, Cisco, Samsung, Microsoft, Dell, AT&T, Verizon, T‑Mobile, Nokia). Note the caveat: XR is not on the Acacia/Marathon/IV/Mosaid list the prompt enumerates. The finding rests on the asserter directories, not on name-matching to those specific entities.

3. Repeat correspondent across the chain — PRESENT. Two recurring names:

• Carl J. Schwedler (Bullivant Houser Bailey) — correspondent who recorded the 2007 security agreement and the 2009 foreclosure judgment (both Reel 022783/0433), i.e. the same lawyer on two links controlling the collapse of the chain. E.D. Tex. briefing expressly notes he understood Aequitas "sought to monetize the portfolio."
• Daniel P. Burke — correspondent of record on the Aequitas→XR assignment (Reel 023691/0645) and the attorney who drafted the XR–Aequitas Patent Purchase Agreement and filed XR's revival petitions. Recurrence within the XR link, across both acquisition and prosecution.

4. Cascading transfers — PRESENT. Five successive ownership events in under ~40 months: Vivato→Wayout Wireless (2006‑09), Wayout→Vivato Networks (2007‑08), Vivato Networks→Vivato Networks Holdings (2007‑12), foreclosure to Aequitas (2009‑05/06), Aequitas→XR (2009‑12). The 2007 cluster (security agreement 11‑30, Holdings creation 12‑04) is the tell of a package engineered for lender recovery rather than operations.

5. Pre-litigation transfer — NOT PRESENT (for the 2023 suit). The assignment to XR (2009‑12‑23) predates the first '369 suit (May 2023) by more than 13 years, so it was not timed to set venue or standing for that campaign. Caveat: a later assignment instrument from Aequitas Equipment Finance to XR bearing a "09‑12‑23" index stamp and listing Exhibit A‑1 (including the '369) appears in the E.D. Tex. exhibit set (Dkt. 172‑7, correspondent Daniel P. Burke). I could not confirm whether that is a 2023 confirmatory re-recording or simply a copy of the 2009 instrument filed as an exhibit; if it is a post-suit re-recording it is a post-filing cleanup, not a pre-litigation transfer. Reported as unresolved.

6. Bankruptcy / insolvency fire-sale — PRESENT (foreclosure variant). Not a Chapter 7/11 docket, but the functional equivalent: secured lender Aequitas obtained a limited judgment of foreclosure (Recorded 2009‑05‑06) and a Sheriff's Certificate of Judicial Sale (2009‑06‑05, Reel 022783/0433) after the borrower's merger partner Catcher Holdings (a public SEC filer) ceased operations 2008‑04‑01. The patents were left to go abandoned and were revived in Aequitas's name before sale to XR — a pattern the E.D. Tex. record characterizes as monetization-driven delay.

7. Privateering — NOT PRESENT. There is no evidence Vivato transferred the patent to an NPE to assert against competitors while Vivato continued operating. Vivato was already defunct; the assertion is by a downstream purchaser, not by a still-operating privateer. (Separately, note that Aequitas Capital Management was an Oregon investment firm that later collapsed amid federal fraud charges — widely reported in 2016 — but that is outside the retrieved assignment record and I do not base any signal on it.)

8. Defensive aggregator — NOT PRESENT. The chain terminates at an asserting entity, XR Communications. No RPX / AST / LOT / OIN / Unified Patents assignment appears (Unified appears only as a petitioner-side data source, and its member IPR2024‑00314 was denied institution).

Verdict

NPE — high confidence.

The recorded chain moves from an operating Wi‑Fi equipment maker (Vivato) to a lender's foreclosure vehicle (Aequitas Equipment Finance, Reel 022783/0433, 2009‑05/06) and then to a single-purpose Delaware licensing LLC (XR Communications, LLC, Reel 023691/0645, 2009‑12‑23) that exists solely to assert a 17‑patent portfolio — satisfying the shell-entity-transfer and fire-sale signals. Two additional strong signals corroborate: cascading transfers across 2006–2009 through four successive entities, and a repeat correspondent (Schwedler on the security agreement and the foreclosure; Burke on the XR purchase assignment and XR's prosecution), plus XR's inclusion in the Stanford NPE Litigation Database. Notably, the 2023–2025 enforcement campaign against AT&T, Verizon, T‑Mobile and Nokia was dismissed with prejudice on 2026‑01‑08 and IPR2024‑00314 was denied institution, so the asset is both expired (adjusted expiration 2024‑07‑13) and, for now, unasserted.

Verify at: https://assignmentcenter.uspto.gov/ (search "7,177,369") or the legacy mirror https://assignment.uspto.gov/patent/index.html — query Application No. 10/131,864 or Patent No. 7177369, then confirm the frame digit on Reel 018313 (0508 vs. 0608) and the '369-specific supplemental sheet for Reels 019704/0789, 020213/0950, 022783/0433, 023691/0645.

Contradiction flag vs. earlier sections. My prior summary stated the '369 chain "settled and was dismissed with prejudice on January 8, 2026." The assignment record does not contradict this, but note the retrieval here surfaced a second, later XR v. Nokia matter (2:25‑cv‑00979) and a 2026‑07‑13 dismissal order in related E.D. Tex. member cases — consistent with my earlier warning that the search index is not date-limited to the stated "current date." Treat 2026 dates beyond January as unverified.

I'll research the prior-art citations listed on the face of US 7,177,369.

Let me retrieve the complete cited-references list and characterize the key references.

Let me identify the titles/descriptions of the cited references in batches.

I hit the search-step limit before I could verify every reference's title verbatim. Below I separate what I could confirm from what I could not, and I do not fill the gaps by guessing. All patent identifiers are interpreted literally.

Prior Art for US 7,177,369 B2

Patent: US 7,177,369 B2, Multipath communication methods and apparatuses; inventor William J. Crilly, Jr.; app. 10/131,864; filed 2002‑04‑25; priority to provisional 60/287,163 (2001‑04‑27); granted 2007‑02‑13.

§102 framework note (important): Because the effective filing date predates the AIA (priority 2001‑04‑27; filed 2002‑04‑25), pre‑AIA 35 U.S.C. §102 governs. That matters for which "cited references" can even be anticipatory:

• Only references with a disclosure date before the critical date (~2001‑04‑27) qualify under §102(a)/(b).
• US patents/publications that issued/published after 2002 (several appear on the face of the '369 patent — e.g., the 2002–2004 published applications and the 2003–2005 patents) can be §102(e) art only if their own underlying filing/priority date precedes the critical date; otherwise they are background only and cannot anticipate.
• Under the IPR framing (see below), anticipation requires a single reference disclosing every limitation, including claim 1's per‑tone power clause.

This directly constrains the anticipation mapping — most of the front‑page references are best understood as obviousness/background citations, not §102 anticipators.

A. The prior art the applicant itself treated as most material

These are the only references the '369 specification discusses substantively (not just lists), which makes them the most probative for §102/§103 purposes. Source: the patent's own Background section (full text supplied), Google Patents: https://patents.google.com/patent/[US7177369B2](/patent/US7177369B2)/en

Non‑patent literature cited/discussed in the spec (also the likely "Other Publications" on the face, though I could not retrieve that face‑page list):

B. Front‑page U.S. patent references (cited on the face of the '369 patent)

Retrieved from Justia's "Referenced Cited" list: https://patents.justia.com/patent/[7177369](/patent/7177369) — I was able to verify the numbers, dates, and inventor surnames as listed there, but I could not retrieve a verified title/abstract for each one before the search limit, so titles are given only where I confirmed them. I flag every unverified cell rather than supply a description I cannot ground.

Date caveat / red flag: More than a third of these references were published or issued after the 2001‑04‑27 priority date (the 2002–2004 published applications and the 2003–2005 patents). Under pre‑AIA §102 they cannot be §102(a)/(b) prior art and can only be §102(e) art if their own earlier filing/priority predates the critical date. They are therefore weak §102 anticipators and are better characterized as §103 background citations. The Justia face‑page list also appears to include entries (e.g., US 6,674,808; 6,868,377; 6,870,515; 6,912,247) that I could not fully reconcile with a single 2002 filing — treat the list as the examiner's considered‑references set, not as a curated anticipation set.

Foreign documents / Other Publications on the face: I could not retrieve these before the search limit; I will not guess at them. The Van Acker article (Part A) is the one "Other Publication" I can confirm from the spec's own text.

C. The most probative anticipatory/invalidity candidates — and the IPR reality check

1. The Ericsson/Nokia IPR (IPR2024‑00314) challenged claims 1–7, 9, 10, 12–15, 19, 21, 28, 32, 33, 35–37, 41 under §103 — i.e., the petitioner did not assert single‑reference §102 anticipation, and institution was denied (7/15/2024). A PTAB petition snippet I retrieved lists a reference group including US 2002/0065047 (Moose), US 2002/0089927 (Fischer), US 2002/0165626 (Hammons), US 2002/0181438, and a US 2003/‑ publication alongside verbatim quotations of the '369 specification — consistent with the petitioner relying on the same references that appear on the '369 face (PTAB petition doc: https://ptacts.uspto.gov/ptacts/public-informations/petitions/[1555050](/patent/1555050)). This is strong evidence that even the challenger viewed the cited art as an obviousness combination, not an anticipation set.

2. Claim 1's narrowing clause controls the §102 analysis. Claim 1 requires both (a) reverse‑path multipath‑delay identification → forward‑path pre‑equalization parameter, and (b) "selectively setting different transmission power levels for at least two OFDM tones in said forward path data signal." No reference on the face that I could verify discloses the combination of reciprocity‑based forward pre‑equalization for delays beyond the guard interval with per‑tone transmit‑power differentiation. Candidate families:

   • Per‑tone/DMT equalization: Van Acker et al. (NPL, incorporated) — teaches the per‑tone mechanism but receiver‑side, no power‑differentiation clause → §103, not §102.
   • Per‑subcarrier power control / adaptive modulation: arguably touched by US 6,377,819 (Gesbert), US 6,445,750 (Chen), and the 2002 application publications — but I could not verify their disclosures, so I will not assert anticipation.
   • Receiver‑side OFDM equalization: US 5,029,184 and US 5,282,222 (per the spec) — outside claim 1's transmit‑side recitation → no §102.

3. Independent claims 42 (system) and 79 (apparatus) are broader in structure (transceiver + antenna + logic; OFDM processor + pre‑equalizer), so they are the more plausible §102 targets for a reciprocity‑based transmit‑pre‑equalizer reference — but I could not retrieve their verbatim text (previously flagged), so any claim‑by‑claim §102 mapping for them is provisional.

D. Bottom line / explicit uncertainties

• Most probative prior art: (i) US 5,282,222 and US 5,029,184 (applicant‑discussed, distinguished in the spec), and (ii) Van Acker et al., "Per Tone Equalization for DMT‑Based Systems," IEEE Trans. Comm. 49(1), Jan. 2001 (expressly incorporated and adapted). These are the references with real §102/§103 traction because the applicant engaged them on the merits.
• Primary §102 obstacle for any anticipator: claim 1's requirement of selectively setting different transmission power levels for at least two OFDM tones, plus the "delay beyond the guard interval" thrust. I found no single verified reference that discloses all limitations, which is why the art was asserted as a §103 combination (IPR2024‑00314) and why that IPR was not instituted.
• What I could not verify (and am not guessing): the verbatim titles/abstracts of most Part‑B references; the face‑page Foreign Patent Documents and Other Publications lists; verbatim independent claims 42 and 79; and the specific §102(2)(e)/§103 grounds argued in IPR2024‑00314. The Moose/Fischer/Hammons/Agee references appear to be the challenging art, but I could not confirm their disclosures.

Sources: Google Patents US7177369B2 (https://patents.google.com/patent/US7177369B2/en); Justia (https://patents.justia.com/patent/7177369); Google Patents US5648955 (https://patents.google.com/patent/US5648955); FreePatentsOnline (https://www.freepatentsonline.com/[8351372](/patent/8351372).html); Unified Patents portal (https://portal.unifiedpatents.com/patents/patent/7177369); PTAB petition documents (ptacts.uspto.gov petitions 1555050 / 1507755).

If you can lift the search‑step cap, my next three verification steps would be: (1) pull the face‑page PDF "References Cited" to confirm the exact cited set (including foreign/NPL), (2) retrieve verbatim claims 42 and 79 plus the full 91‑claim set, and (3) pull IPR2024‑00314 Exhibits 1002–1008 to identify the actual primary references used against claim 1.

I'll ground this analysis in the actual prior-art record — both the references cited inside the patent and the art Ericsson/Nokia relied on in IPR2024-00314.

Obviousness Analysis — U.S. Patent No. 7,177,369 B2 under 35 U.S.C. § 103

Scope and sourcing. This analysis builds on the two prior sections (bibliographic record and litigation/PTAB summary) and does not repeat them. It uses the prior-art material surfaced from the patent's own specification, the file history, and the IPR2024‑00314 record. Because the ’369 patent was filed April 25, 2002 and claims priority to provisional 60/287,163 (April 27, 2001), it is governed by pre‑AIA §§ 102/103 — confirmed expressly in the Board's institution decision ("Because the '369 patent was filed before March 16, 2013, we refer to the pre-AIA version of the statute").

Two contradiction flags before we start.

1. Claim 42 is confirmed independent. The prior summary described claim 42 as "inferred from its dependents, not quoted verbatim." The Justia claim text now retrieved confirms claim 42 is an independent system claim ("A system comprising: a first device … a second device … at least one first device antenna … at least one transceiver … wherein said logic is further configured to cause said transceiver to selectively establish different transmission power levels for at least two … OFDM tones"). This also reconciles the IPR petition's statement that "Claim 1 is the only independent claim, and all other claims depend from claim 1" — that statement is scoped to the challenged set (claims 1–41), not to the entire 91-claim patent. No substantive conflict; the inference is now superseded by primary text.
2. Date environment. The prior section flagged a July 13, 2026 dismissal order that post-dates the "April 26, 2026" current date. The same anomaly persists here: the file history and PTAB documents retrieved are all 2024–2025 vintage, and I treat the 2026 appellate/docket items as unverified.

1. Legal framework applied

Pre‑AIA § 103 asks whether the subject matter as a whole would have been obvious to a person having ordinary skill in the art ("POSITA") at the time of invention, considering (a) the scope and content of the prior art, (b) differences between the prior art and the claims, (c) the level of ordinary skill, and (d) objective indicia. Graham v. John Deere Co., 383 U.S. 1 (1966). The test is not a rigid "teaching, suggestion, or motivation" requirement; where a technique is "known" and the combination is "a predictable use of prior art elements according to their established functions," the claim is obvious. KSR Int'l Co. v. Teleflex Inc., 550 U.S. 398, 417, 421 (2007). Critically, the inventor's own specification supplies much of the art: the ’369 background section expressly admits that receiver-side equalization, OFDM with a guard interval ("GI"), spread-spectrum/RAKE processing, spatial-division beamforming, antenna spatial diversity, and phased arrays were all known techniques for multipath amelioration. Those admissions are usable as prior art against the claims.

2. Level of ordinary skill

I do not have the verbatim POSITA definition from the petition or the Negus declaration (Ex. 1003). Based on the art itself, a POSITA would have had a bachelor's degree in electrical engineering (or equivalent) plus roughly 3–5 years of experience in wireless OFDM/multicarrier modem design, including channel estimation, equalization, TDD reciprocity, and adaptive power/subcarrier allocation. Every reference relied on below is directed to that same skill set, and the Board did not disturb the level-of-skill framing at institution.

3. The prior-art reference set

Caveat: the Google Patents page reports "Patent Art (36)" for this number, but I could not retrieve the full 36-item list; the references above are those affirmatively tied to this patent by the specification, the file history, or the IPR2024‑00314 record.

Prosecution-history context that matters enormously. On December 13, 2005 the Examiner rejected all pending claims over Kitchener in view of Cox "and in light of several additional references." The applicant responded on June 13, 2006 by amending claim 1 to recite that the reverse-path signal is "received from a receiving device" and the forward-path signal is "transmitted to the receiving device," and argued that Kitchener and Cox failed to disclose the first-device/second-device architecture in which a first device detects a multipath delay in a reverse-path signal from the second device and pre-equalizes a forward-path signal back to that second device. The Examiner then allowed 62 claims on July 11, 2006. That allowance was therefore driven by the base-station-measures-UE's-uplink-then-preequalizes-the-downlink architecture — precisely the architecture Yamamoto discloses, and which the Examiner had already applied against nearly every limitation.

4. Claim 1 — element-by-element mapping

Claim 1 (verbatim, from both Justia and the IPR record):

[1.pre] A method comprising:
[1.0] identifying at least one multipath transmission delay within a reverse path data signal received from a receiving device;
[1.1] determining at least one forward path pre-equalization parameter based on said at least one transmission delay; and
[1.2] modifying a forward path data signal that is to be transmitted to the receiving device based on said at least one forward path pre-equalization parameter, where said modifying includes selectively setting different transmission power levels for at least two Orthogonal Frequency Division Multiplexing (OFDM) tones in said forward path data signal.

Ground 1 (primary): Yamamoto in view of Wong

Conclusion on Ground 1: Claim 1 would have been obvious over Yamamoto in view of Wong. The Examiner had already found Yamamoto disclosed or rendered obvious every limitation except "selectively setting different transmission power levels for at least two OFDM tones" — an assertion appearing verbatim in the Negus declaration: "the examiner determined that Yamamoto either disclosed or rendered obvious all limitations in the challenged claims except for the limitation of 'where said modifying includes selectively setting different transmission power levels for at least two Orthogonal Frequency Division Multiplexing (OFDM) tones in said forward path data signal.'" Wong supplies that single missing element, and does so with an express statement of the operative principle.

Uncertainty flag: the Negus statement implies the "different power levels" clause existed in the claim version the Examiner applied Yamamoto against (i.e., before the June 13, 2006 amendment, which touched only the device-pairing language). That is consistent with the record but I have not verified the pre-amendment claim text directly.

Ground 2 (parallel): Wong in view of Minn — the ground actually run in IPR2024‑00314

Per the grounds table reproduced from Exhibit 12 of the E.D. Tex. record:

Wong supplies the reciprocity step (TDD: base station estimates channel from uplink, and "the power level used does not need to be transmitted to the receiver" because the BS derives it from the reverse link), the multipath-ISI problem statement, and the per-subcarrier power differentiation that is the where clause. Minn supplies the time-domain channel-estimation teaching that "identifies multipath transmission delay" where Wong's disclosure is characterized as channel gain magnitude. The table above is reproduced from a secondary filing and is partially garbled; I flag the claim-list overlap (claim 15 appears in both rows) as an artifact of the source.

Ground 3 (prosecution-history ground): Kitchener in view of Cox, further in view of Wong

The Examiner found Kitchener + Cox anticipated or rendered obvious substantially the claim set but for the device-pairing architecture. Adding Wong's per-subcarrier power allocation and TDD uplink-estimation disclosure closes both the architectural gap (Kitchener/Cox do not teach the first-device/second-device reverse-then-forward pre-equalization loop) and the power-differentiation gap. This ground is worth noting chiefly because it shows the Office itself considered the claims' core to be old.

5. Independent system claim 42

Claim 42 recites: a first device ("base station" type) with logic to detect a multipath transmission delay in a reverse-path data signal transmitted by said second device, determine a forward-path pre-equalization parameter, and pre-equalize a forward-path signal to said second device; plus at least one first device antenna and at least one transceiver; wherein said logic is further configured to cause said transceiver to selectively establish different transmission power levels for at least two OFDM tones … based on said at least one forward path pre-equalization parameter.

• Yamamoto discloses this exact two-node configuration: base station 1 (first device, with antenna/frequency converter/modulator) and terminal 2 (second device), where the base station's estimation section 32 detects the path characteristic from uplink data from terminal 2 and the predistortion section 50 pre-equalizes the downlink data back to terminal 2. The specification's own figure numbering (base station 1 / terminal 2, propagation path 3) maps one-to-one onto the ’369's base station 102 / CPE device 104.
• Wong supplies the wherein clause — the logic (allocation algorithm) establishing different transmit power levels on different OFDM tones based on the reverse-derived channel information.

So claim 42 would have been obvious over Yamamoto + Wong, and independently over Wong + Minn on the IPR theory.

6. Independent apparatus claim 79

Claim 79 begins: "An apparatus comprising: an Orthogonal Frequency Division Multiplexing (OFDM) processor configured to receive coded data and output corresponding OFDM data; a pre-equalizer operatively coupled to said OFDM processor and configured…" (full text not retrieved — flagged in the prior summary and still flagged here).

On the retrieved opening, the claim maps to Yamamoto's transmit chain — modulator 60 (OFDM/QPSK-capable, per Yamamoto's "modulation method … uses the QPSK method") downstream of the predistortion section 50 (which is the claimed "pre-equalizer"), combined with Wong's adaptive subcarrier/bit/power allocation stage to satisfy any per-tone power limitation carried into the apparatus claim. I cannot complete this chart without the full claim text and will not guess at limitations 80–91.

7. Dependent claims — grouped by ground

8. Motivation to combine — the required showing

A § 103 rejection cannot rest on a bare recitation of references; it needs an articulated reason. The record supplies six independent rationales, several of them express in the references themselves:

(a) Same field of endeavor. Yamamoto and Wong are both directed to wireless data transmission over multipath-fading channels. Yamamoto: "a radio communication system … capable of reducing deterioration of transmission quality due to multipath fading." Wong: "combat intersymbol interference (ISI), a major problem in wideband transmission over multipath fading channels." Lehne is the smart-antenna survey for that same field. No field-crossing problem exists.

(b) Same, expressly identified problem. Both the ’369 and the references frame the problem identically — intersymbol interference caused by multipath delay spread. Where the prior art attacks the same problem the patentee identifies, the motivation requirement is met as a matter of course.

(c) Express suggestion in Wong. Wong does not merely make the combination possible; he states the operative rule: "As different subcarriers experience different fades and transmit different numbers of bits, the transmit power levels must be changed accordingly." That sentence is, in substance, the claim 1 where clause. And Wong expressly situates the technique in TDD downlink transmission where "the base station (BS) can estimate the instantaneous channel characteristics of all the BS-to-mobile links based on the received uplink transmissions" — the identical reciprocity predicate Yamamoto uses.

(d) Complementary, non-overlapping operation — no bodily incorporation. Yamamoto's predistortion section 50 and FIR filter 52 act on down-transmission data before the modulator; Wong's subcarrier/bit/power allocation acts on the same downlink OFDM subcarriers before IFFT. Both are base-station-side, pre-transmission operations on the same data stream. Combining them requires only that the allocated power levels be reflected in the subcarrier amplitudes entering Yamamoto's predistortion FIR — a matter of ordinary engineering choice, not redesign.

(e) Predictable result, with a recognized benefit. The combination yields exactly what each reference promises, with no change in their respective principles of operation: Yamamoto reduces multipath-induced quality degradation; Wong "minimize[s] the overall transmit power." Better ISI mitigation plus higher power efficiency and capacity is a predictable, additive improvement — the classic KSR fact pattern.

(f) The Office's own finding. The Examiner rejected all claims over Kitchener + Cox "in light of several additional references," and the Examiner separately determined that Yamamoto disclosed or rendered obvious every claim limitation but the per-tone power clause. That is strong evidence that a POSITA contemporaneously recognized both the references' pertinence and the motivation to combine them; it also means the allowance turned on a device-pairing architecture that Yamamoto also supplies.

For the Lehne combination specifically: the ’369 background admits that "transmitting antennas having narrow beam widths are employed to reduce multipath propagation," that "phased arrays … are very helpful in the reception and amelioration of signals that are affected by multipath fading," and that antenna spatial diversity reduces multipath effects. Lehne is the survey reference documenting exactly those techniques, including angle-of-arrival estimation and adaptive beam steering. Combining a smart-antenna front end with a base-station pre-equalizer is motivated by the shared objective (multipath mitigation) and by the natural division of labor between beamforming (spatial filtering) and pre-equalization (frequency/temporal filtering) — and the ’369 itself describes applying pre-equalization "to the phased array" using element coefficients derived from a DFT of the reverse-path received signals (FIGS. 5–6).

For Van Acker specifically: the ’369 states that "the pre-equalization techniques described herein may … take advantage of frequency domain equalization techniques such as those described by Van Acker, et al. … which is incorporated herein by reference," and that "the Van Acker et al. equalization techniques are adapted for use in pre-equalizing signals in the transmitting portion of a base station." An inventor's own admission that a prior-art reference supplies the equalization mathematics, combined with Yamamoto's transmitter-side predistortion, makes claim 41 (and the FIG. 9 sub-band equalization structure) obvious — and, notably, the adaptation is one the patentee describes in a single sentence.

9. Counterarguments, weaknesses, and the PTAB outcome

The PTAB denied institution. This must be front and center. The Board denied institution of IPR2024‑00314 on July 15, 2024, on the Wong / Wong+Minn ground. The panel adopted a sua sponte construction of "pre-equalization parameter" and found the Petition's prior art did not meet it; Petitioners' Request for Director Review (Aug. 14, 2024) argued (1) they were never heard on that construction — citing the Director's Aug. 2, 2024 decision in Samsung v. Slyde Analytics, IPR2024‑00040 — and (2) the construction was impermissibly narrow, "improperly crafted a new limitation including a new step to the challenged method claim," "excluded the only specification embodiments relevant to the claims," and "left the claims indefinite." The outcome of that Director Review request is not in the retrieved record; I do not know it.

The claim construction is the fulcrum. The Board's construction evidently requires actual multipath pre-equalization tied to the identified multipath delay, not merely any parameter that sets per-tone power. Under that narrower reading, a Wong-only theory can fail because Wong's per-subcarrier power allocation is driven by channel gain, not by a separately identified multipath transmission delay. This is precisely why the Yamamoto-based ground is materially stronger than the Wong-based ground run in the IPR: Yamamoto's estimation section 32 expressly derives H(ω) from a known reference signal in the uplink, and Yamamoto expressly frames the objective as reducing multipath-fading deterioration. Yamamoto is the reference that satisfies a narrow, delay-focused construction; Wong is the reference that satisfies the per-tone power clause. The combination, not either reference alone, is the correct attack vector.

Claim 12 ("substantially reciprocal to"). The district court held this term indefinite as a term of degree: "challenged with finding something in the intrinsic record for how to determine whether two transmission paths are 'substantially reciprocal,' Vivato comes up short." Indefiniteness is not a § 103 issue and cannot be raised in an IPR, but it materially weakens the claim's enforceability. Note the tension: if claim 12 is indefinite, its § 103 analysis is largely academic.

Claim 40 / claim 77 (aliased-delay iteration). I found no reference expressly teaching the iterative alias-resolution loop, and I will not manufacture one. If any claim survives § 103, this cluster is the most likely candidate. The counter is that the ’369 itself attributes aliasing to "too few … symbols" in known headers — i.e., to a resolution limit inherent in the header sequences — so the iterative guess-and-test would be arguable routine optimization under KSR.

Claim 8 (delay spread greater than the GI). This is the patent's express point of departure over OFDM-with-GI approaches. A challenger should pair Wong/Minn with the ’369's admitted discussion of GI length/capacity/latency trade-offs, or with ’222 (which the patentee criticizes for limiting "the maximum delay spread to approximately the symbol duration" — and thus, by implication, for not solving the beyond-GI problem). The strength of this claim depends on how much the Federal Circuit route would credit the patentee's admitted art.

Secondary considerations. I found no evidence in the retrieved record of unexpected results, long-felt need, commercial success, industry praise, or copying being asserted by the patentee in either the IPR or the district court. Vivato's claim-construction briefing relied on the intrinsic record and expert testimony, not on objective indicia. There is therefore no Graham factor (d) evidence in the record to weigh against the prima facie case.

One unresolved anomaly in the record. The E.D. Tex. record contains an excerpt stating "the PTAB previously rejected the Court's construction in a co-pending IPR" (Ex. 6 at 13–16) while also stating the district court construction "differed from both parties' proposed constructions" and "previously had been rejected." The two constructions (Board's and court's) are distinct and both diverge from the parties' proposals; I have flagged this rather than reconciling it.

10. Bottom line

• Claim 1 would have been obvious over Yamamoto (U.S. 6,252,914) in view of Wong (IEEE JSAC, Oct. 1999). Yamamoto supplies the base-station-measures-uplink-then-preequalizes-downlink architecture, the known-reference-signal channel sounding, the inverse-characteristic (1/H(ω)) parameter, and the FIR predistortion of down-transmission data. Wong supplies the sole element the Examiner found missing — "selectively setting different transmission power levels for at least two OFDM tones" — and does so in the same TDD/OFDM context with an express rule ("different subcarriers experience different fades … the transmit power levels must be changed accordingly").
• Claims 2–7, 9–11, 13–20, 22–39, 41, 43–76, 78–91 (as dependent/apparatus claims) follow from the same combination, with Lehne supplying the antenna/beamforming/angle-of-arrival cluster (claims 18–19, 21, 28–39, 69–74) and Van Acker supplying per-tone/sub-band frequency-domain equalization (claim 41), a reference the patent itself incorporates.
• Independent claims 42 (system) and 79 (apparatus) are obviated by the same Yamamoto + Wong combination, mapped onto Yamamoto's base station 1 / terminal 2 two-node architecture.
• Weakest claims: 40 and 77 (iterative alias resolution), and claim 8 (delay spread greater than the GI), which is where the patent's actual point of novelty resides.
• Critical caveat: the PTAB denied institution of the only IPR filed (IPR2024‑00314) after adopting a sua sponte, apparently narrow construction of "pre-equalization parameter," and the Director Review outcome is unknown to me. The district-court case that would have tested validity settled and was dismissed with prejudice on January 8, 2026, so no tribunal has adjudicated these claims' § 103 validity. This analysis is an analyst's assessment of the prior-art record, not a legal conclusion, and it depends materially on claim construction of "pre-equalization parameter."