US 8289939

I'll search for this specific patent and check for any CAFC 2026 docket activity.

Let me drill into the litigation/PTAB records and check specifically for any Federal Circuit 2026 activity.

Let me pull the granted claim set and verify the independent claims precisely.

US 8,289,939 B2 — "Signal Communication Coordination"

Important caveat up front: I could not access the USPTO PatentCenter record directly in this session. The bibliographic data below is drawn from the Google Patents family record for US8289939B2 (authoritative text supplied to me), the Cisco IPR petition filed in IPR2022-00958 (which quotes the '939 specification and claims), and litigation dockets. Where I could not verify something to a high degree of confidence, I say so explicitly. I have not auto-corrected any identifier; all numbers are reported literally as they appear.

1. Bibliographic data

Ownership chain (per recorded assignments): Vivato, Inc. → Wayout Wireless, LLC (2006-09-21, first amendment to asset purchase agreement) → Vivato Networks, LLC (2007-08-06, change of name) → Vivato Networks Holdings, LLC (2007-12-07) → Aequitas Capital Management / Aequitas Equipment Finance, LLC (2007–2009, security agreement, loan assignment, limited judgment of foreclosure, sheriff's certificate of judicial sale) → XR Communications, LLC (2009-12-23).

Note a minor discrepancy in the public records: Google Patents lists the priority date as 2002-11-04, while the associated PCT publication WO 2004/042528 A2 (published 2004-05-20, original assignee Vivato Inc.) is indexed with a priority date of 2002-11-03 and application date 2003-11-02. I report both literally rather than reconciling them.

2. Abstract (verbatim)

"An exemplary access station for wireless communications includes: a wireless input/output unit that is configured to establish multiple access points; and signal transmission/reception coordination logic that is capable of ascertaining that an access point of the multiple access points is receiving a signal and that is adapted to restrain at least one other access point of the multiple access points from transmitting another signal responsive to the ascertaining that the access point is receiving the signal. An exemplary method includes: monitoring multiple respective indicators acquired from multiple respective baseband units; detecting whether at least one respective indicator of the multiple respective indicators is affirmatively indicating that a signal is being received; and if so, providing at least one instruction to at least two medium access controllers of multiple respective medium access controllers, the at least one instruction restraining the at least two medium access controllers from causing a transmission."

3. Independent claims — plain-language overview

The patent is directed to a co-located multi-beam / multi-access-point base station (a beamformed "Wi-Fi switch") in which a signal being received on one access point can be "thrashed" by a simultaneous downlink transmission on a different access point. The independent claims cover (a) the apparatus that suppresses that transmission, and (b) the coordination logic/method that aggregates baseband receive indicators.

Independent claim 1 — Apparatus (wireless access station with coordinated access points).

• A wireless input/output (I/O) unit establishes a plurality of access points (the spec maps each access point to a communication beam of the antenna array).
• Signal transmission/reception coordination logic monitors those access points for received signals and ascertains that a first access point is receiving a first signal.
• In response, the logic restrains at least two other access points from transmitting.
• The logic also restrains an access point from transmitting on a first channel in response to ascertaining that an access point is receiving a signal on a second, different channel (the inter-channel/inter-modulation case).
• Dependent claims add: access points are co-located (claim 2); IEEE 802.11 operation (claim 3); the received signal is an uplinked packet or a portion thereof, e.g., a preamble (claims 4–6); restraint applies to downlink signals (claim 7); restraint persists while the reception continues (claim 8); each access point corresponds to a communication beam (claim 9); each access point is associated with a MAC/baseband-unit pair (claim 10); the coordination logic is MAC coordinator logic (claim 11), which may link two or more access stations (claim 12).

Independent claim 15 — Apparatus (multi-reception restraint).

• Same "wireless I/O unit establishing a plurality of access points" plus "signal transmission/reception coordination logic" preamble as claim 1.
• The logic ascertains, by monitoring the access points for received signals, that (i) a first access point is receiving a first signal on a first channel and (ii) a second access point is receiving a second, ongoing signal on a second channel.
• In response, it restrains at least a third access point from transmitting a third signal on a third channel, where the restraint prevents degradation to the first and second signals.

Independent claim 30 — Apparatus (cross-channel restraint).

• Same preamble.
• The logic ascertains, by monitoring the access points for received signals, that a first access point is receiving a first signal on a first channel.
• In response, it restrains at least a second access point from transmitting a second signal on a second channel different from the first channel.

Sourcing note: the claim 1 text above is taken from the granted-patent claim listing for US 8,289,939. Claims 15 and 30 are described and quoted (with bracketed element labels [15B.1], [30B.1], etc.) in Cisco's IPR petition for IPR2022-00958. In that petition Cisco states that "the two challenged independent claims recite substantially similar subject matter" and that "[t]he primary difference between the independent claims lies in the circumstances of when reception of signals is ascertained and when an access point is restrained." Cisco challenged claims 15–22 and 30–35 only. Uncertainty I cannot resolve from the sources retrieved: the patent appears to contain more than these three independent claims (the claim set numbers through at least claim 35), and I could not retrieve the full text of claims 2–14, 23–29, and 36+ or confirm whether a method/means-plus-function independent claim (the patent's pre-grant publication included method and "means for" claims, e.g., claim 80 and claim 89 of US 2004/0223476 A1) survived into the granted claim set. The abstract does recite a method ("monitoring… detecting… providing at least one instruction to at least two medium access controllers"), so a corresponding method claim likely exists, but I have not verified its number or exact wording.

Also worth noting (claim-construction relevance): In the parallel district court litigation, a special master report and recommendation (as summarized in the Cisco petition, citing CISCO-1013 and CISCO-1014) treated the "signal transmission/reception coordination logic" limitations of claims 15 and 30 as means-plus-function terms under 35 U.S.C. § 112 ¶ 6, with corresponding structure identified as "signal transmission/reception coordination logic 404 (with the characteristics and configuration set forth for the signal transmission/reception coordination logic 404 in the '939 patent), and equivalents thereof." Defendants in that litigation separately contended the limitation was indefinite for insufficient disclosed structure. I report these as party/special-master positions, not as adjudicated outcomes.

4. Litigation and PTAB posture (including what I did not find)

PTAB:

• IPR2022-00958, Cisco Systems, Inc. v. XR Communications LLC d/b/a Vivato Technologies — filed May 4, 2022; challenged claims 15–22 and 30–35 of the '939 patent as obvious over U.S. Patent No. 7,158,501 to Kasami (Ground 1: Kasami alone). Grounds for standing and the challenge are set out in the petition. The proceeding was terminated November 28, 2022 with institution denied (Google Patents characterizes it as "Not Instituted – Merits"); the panel was Judges Barbara Parvis, James Mayberry, and Terrence McMillin (Tech Center 2400, Art Unit 2476). The Cisco petition also expressly states: "Petitioner does not agree that the '939 patent is entitled to priority to either provisional."
• Google Patents' litigation field for this patent lists only this one PTAB case (the "Petitioner" field on that page is blank, which I read as a data-completeness gap, not as an absence of a petitioner — the underlying petition is captioned to Cisco Systems, Inc.).

District court activity involving the '939 patent (per Google Patents' litigation links and third-party databases):

• E.D. Tex. 2:23-cv-00202 (XR Communications LLC d/b/a Vivato Technologies v. AT&T Inc., et al.) — the '939 patent is among the patents in suit (with 8,737,511; 10,715,235; 10,594,376; 7,177,369). AO 120 report filed January 8, 2026 records that all claims and causes of action were dismissed with prejudice and counterclaims dismissed without prejudice.
• Related 2023 E.D. Tex. cases: 2:23-cv-00203 and 2:23-cv-00204.
• 2021 California cases: C.D. Cal. 2:21-cv-04912, 2:21-cv-04942, 8:21-cv-01064; N.D. Cal. 3:21-cv-04679; W.D. Tex. 6:21-cv-00623.
• 2025 cases: E.D. Tex. 2:25-cv-00697, -698, -699 (filed July 8, 2025) against AT&T entities, Verizon entities, and T-Mobile USA, asserting inter alia 8,161,528; 8,199,724; and 8,289,939; also E.D. Tex. 2:25-cv-01253 and W.D. Tex. 7:25-cv-00590, 7:25-cv-00591.
• The Google Patents family record also lists an E.D. Tex. case numbered 2:26-cv-00001.

CAFC 2026 docket search — result: no appeal found. I searched Federal Circuit 2026 materials (including the September 2026 oral-argument calendar and 2026 weekly Federal Circuit summaries) for XR Communications / Vivato and for patent numbers 8,289,939 / 8,199,724 / 8,161,528 and found no 2026 Federal Circuit appeal docketed under any of those identifiers. I want to be explicit about the limits of this: my searches were of secondary aggregators and published calendars, not a direct PACER/CM-ECF or CAFC docket query, and the January 8, 2026 dismissal-with-prejudice in 2:23-cv-00202 could in principle give rise to an appeal whose docketing notice did not surface in my searches. Treat "no CAFC 2026 appeal" as a negative search result, not as a verified absence.

5. Summary of the invention in one paragraph

The '939 patent addresses the "thrashing" problem that arises when one base station simultaneously runs multiple co-located access points (each served by a respective communication beam formed by a phased antenna array). Because a transmission on one beam can be received, at high level, by the front end of another beam on the same (or an adjacent/improperly-bounded) channel, a downlink packet sent on beam y can destroy an uplink packet being received on beam x. The patent's solution is coordination logic — implemented as MAC coordinator logic or, in alternative embodiments, at the baseband layer or distributed across spatially separated access stations — that collects receive indicators (e.g., CCA busy indications) from the multiple baseband units, combines them (logically "OR"ing them, and optionally grouping them per channel), and feeds a "constructive receive indicator" back to the MACs so that while any enabled baseband unit is receiving, the other MACs are restrained from causing transmissions. The specification adds per-channel grouping (channel assignment information), masking of selected indicators (a masking register) so that an overlapping foreign subnet cannot permanently mute the station, watchdog timers keyed to maximum packet duration and to per-channel receive states, and scanning logic that detects other access points' BSSIDs in order to mask the corresponding beam.

6. Sources

• US 8,289,939 B2 family/bibliographic/legal-status record: https://patents.google.com/patent/US8289939/en
• Granted claim text and specification excerpts: https://patents.justia.com/patent/8289939
• Pre-grant publication claim set: https://patents.justia.com/patent/20040223476 and https://www.freepatentsonline.com/y2004/0223476.html
• Cisco IPR petition quoting the '939 claims (Exhibit 11 to Doc. 81-12 in E.D. Tex. 2:23-cv-00202): https://www.courtlistener.com/docket/67349582/81/12/xr-communications-llc-dba-vivato-technologies-v-att-inc/ and the corresponding PDF at https://storage.courtlistener.com/recap/gov.uscourts.txed.[222063](/patent/222063)/gov.uscourts.txed.222063.81.12.pdf
• IPR2022-00958 docket (filing date, denial, judges): https://gaeflexstaging-dot-docketupdate.appspot.com/cases/PTAB/IPR2022-00958/Cisco_Systems_Inc._v._XR_Communications_LLC_dba_Vivato_Technologies/
• E.D. Tex. 2:23-cv-00202 AO 120 report / dismissal entered 1/8/2026: https://archive.org/download/gov.uscourts.txed.222063/gov.uscourts.txed.222063.300.0.pdf
• Stanford NPE litigation database, case 2:25-cv-00697 (patents 8,161,528; 8,199,724; 8,289,939): https://npe.law.stanford.edu/case/[307184](/patent/307184)
• Federal Circuit September 2026 argument calendar (searched; no XR/Vivato entry): https://www.cafc.uscourts.gov/wp-content/uploads/OralArguments/PublicCalendar-September2026.pdf
• PCT family member: WO 2004/042528 A2 record: https://portal.unifiedpatents.com/patents/patent/WO-2004042528-A2

I'll research litigation involving US patent 8289939. Let me run several targeted searches.

Let me dig deeper into the specific cases and their outcomes.

Litigation Involving U.S. Patent No. 8,289,939

Patent: U.S. 8,289,939 B2 — "Signal communication coordination" (filed Nov. 3, 2003; issued Oct. 16, 2012; priority to Nov. 4, 2002 provisional applications 60/423,702 and 60/423,696; app. 10/700,342).
Owner/Plaintiff: XR Communications, LLC d/b/a Vivato Technologies (originally assigned to Vivato, Inc.; chain of title through Wayout Wireless, Vivato Networks, Aequitas, to XR Communications).

This patent has been asserted in a large, interrelated campaign by XR Communications/Vivato — most often as one of several patents in a single suit, not on its own. Below are the matters I could identify and corroborate, with the caveat noted at the end.

1. District Court Litigation

2. Post-Grant Proceedings (PTAB)

Note: Several other XR/Vivato IPRs exist, but they target different patents in the family (e.g., IPR2022-00613 and IPR2024-00868 on the '511 patent; IPR2022-01155 and IPR2024-00613 on the '235 patent; IPR2024-00314 on the '369 patent) — those are not proceedings on the '939 patent.

3. Key Substantive Developments on the '939 Patent

• Claim construction (C.D. Cal., D-Link lead case): The Special Master and Judge Carter construed "wireless input/output (I/O) unit" to have its plain and ordinary meaning, and supplied corresponding structure for the "signal transmission/reception coordination logic" limitation. (Order at D.I. 312, adopting R&R D.I. 280.)
• Claim construction (W.D. Tex., Sept. 30, 2022): Judge Albright construed "signal transmission/reception coordination logic" as having its plain and ordinary meaning and not invoking §112(6) means-plus-function.
• Claim construction (E.D. Tex., 2024): In the AT&T lead case, the court disagreed and held the term to be means-plus-function, identifying Figure 7/12 algorithms as the corresponding structure; Vivato lodged a partial objection (D.I. 115). This §112 dispute over the '939 patent was a central battleground.
• IPR2022-00958 was denied institution, so the challenged '939 claims were not cancelled at the PTAB.

4. Important Caveats

1. Scope discipline: I limited results to matters involving U.S. 8,289,939. XR Communications/Vivato files have a very large overlapping portfolio ('231, '296, '728, '369, '511, '376, '235, '939, etc.), and many published decisions in these suits address sibling patents rather than the '939 patent. Where a case is in the '939 "litigation" record of Google Patents/Unified Patents or Stanford's NPE database but I could not independently confirm the assertion, I flagged it as such.
2. Unconfirmed 2025–2026 cases: For the very recent dockets (2:25-cv-00697 through -00699, 2:25-cv-01253, 7:25-cv-00590/-00591, 2:26-cv-00001), I have court/case numbers and jurisdiction but could not reliably confirm all defendant identities, exact filing dates, or current status from the retrieved sources. These should be verified against PACER/CourtListener before being relied upon.
3. "Outcome/status" lag: Docket data (PACER/RECAP/Unified) can lag. The E.D. Tex. AT&T lead case and the 2025 filings are, to the best of the sources retrieved, still active as of the information available.

Primary sources consulted: Google Patents family/litigation page (https://patents.google.com/patent/[US8289939](/patent/US8289939)/en); Stanford NPE Litigation Database (https://npe.law.stanford.edu/patent/8289939 and https://npe.law.stanford.edu/case/[307184](/patent/307184)); Unified Patents litigation/PTAB pointers; CourtListener/RECAP dockets (E.D. Tex. 2:23-cv-00202); and the Cisco IPR2022-00958 petition reproduced as an exhibit in that docket.

If you need me to confirm the unverified 2025–2026 defendants, filing dates, and dispositions, I can run targeted docket lookups case-by-case.

I'll verify the structured data against live sources, since the "PTAB proceedings on file" block and the earlier sections of this analysis appear to conflict.

Let me pull the institution-denial reasoning and check for any other AIA trials on the '939, plus any appeal.

Two important threads to close: the denial's reasoning, and a possible second '939 IPR ("Defendants' IPR on the '939 patent") referenced in the joint claim construction statement.

PTAB / AIA Trial Proceedings — U.S. Patent No. 8,289,939

Conflict flagged up front. The structured "PTAB proceedings on file" block in this task states that the USPTO ODP API returns no AIA trial proceedings for the '939 patent. That is incomplete, not authoritative on the facts: a real, docketed IPR exists — IPR2022-00958 — and it is documented in three independent places I retrieved (the Google Patents family record supplied in this analysis, the Cisco petition reproduced as Plaintiff's Ex. 11 / Doc. 81-12 in E.D. Tex. 2:23-cv-00202, and the PTAB docket mirror). The most likely explanation is that IPR2022-00958 (filed 2022-05-04, terminated 2022-11-28) predates or falls outside the ODP ingest window rather than that it never existed. Per the task instructions, I treat the structured block as the default list and web search as the source for older proceedings the ODP has not indexed — I have flagged the discrepancy rather than silently resolved it.

I could not open the four corners of the Board's institution-denial decision in this session (tool budget exhausted before I reached the PTAB E2E / PTAB Decisions document itself), so I do not quote the panel's denial reasoning verbatim and I do not state a denial ground I cannot source. That gap is called out below.

Proceedings overview

One AIA trial proceeding is confirmed on the '939 patent — IPR2022-00958 (Cisco Systems, Inc. v. XR Communications LLC d/b/a Vivato Technologies) — and it was terminated by denial of institution on 2022-11-28, meaning zero challenged claims were invalidated, zero were sustained on the merits, and zero reached a Final Written Decision; the bottom line for a defendant is that the '939 patent is PTAB-untested and therefore "un-narrowed" by any AIA ruling, which cuts both ways: the patent owner cannot be collaterally estopped on any claim, but no defendant has ever gotten the benefit of a Board cancellation either.

IPR2022-00958 — Cisco Systems, Inc. v. XR Communications LLC d/b/a Vivato Technologies

• Type: Inter Partes Review (AIA), pre-institution phase only.
• Filed: 2022-05-04.
• Status: Institution Denied (verbatim from the PTAB docket mirror). Terminated 2022-11-28. Google Patents characterizes the outcome as "Not Instituted – Merits"; the docket style itself reads "Status: Institution Denied." Gloss: no trial was instituted, so no Final Written Decision issued and no claim of the '939 was canceled, narrowed, or confirmed.
• Judge panel: Judges Barbara A. Parvis, James Mayberry, and Terrence McMillin (Tech Center 2400, Art Unit 2476). The same panel composition (Parvis, McMillin) also sat on the related IPR2018-00762 against XR's '231 patent, so this is a panel already familiar with the Vivato portfolio.
• Petition grounds (per the petition's own § V and Ground 1):
  • Challenged claims: claims 15–22 and 30–35 only (the two independent apparatus claims 15 and 30 and their dependents).
  • Art: U.S. Patent No. 7,158,501 to Kasami et al. ("Kasami"), filed 2002-05-29, asserted as prior art under at least pre-AIA 35 U.S.C. § 102(e).
  • Statutory basis: § 103(a) obviousness — a single ground, "Claims 15–22 and 30–35 would have been obvious over Kasami." No § 102 anticipation ground; no § 112 ground was presented.
  • Supporting evidence: Expert Declaration of Dr. Kevin Jeffay (Ex. 1003) and a support exhibit set including the Gast 802.11 handbook (Ex. 1006), Lehne (Ex. 1009), O'Hara & Petrick IEEE 802.11 Handbook (Ex. 1012), and the C.D. Cal. claim-construction record (Exs. 1013–1014).
  • Priority challenge: The petition states expressly in footnote 1: "Petitioner does not agree that the '939 patent is entitled to priority to either provisional." That is a substantive position, not a throwaway — it would move the effective date from 2002-11-04 to 2003-11-03 and enlarge the qualifying art.
  • Claim-construction posture adopted for the IPR: Cisco took the § 112 ¶ 6 position for free — it adopted, "solely for purposes of this proceeding," the C.D. Cal. structure finding for "signal transmission/reception coordination logic" (see next bullet) while reserving the right to challenge the limitation as indefinite in another forum (footnote 4).
• Institution decision: Denied — date of termination 2022-11-28 (≈ 208 days after filing, consistent with a § 314(a) decision on the institution deadline). I did not retrieve the text of the decision, so I cannot tell you why the panel declined. Three candidate rationales are visible in the record, and I will not pick one without the document:
  1. Discretionary denial under § 314(a) (Fintiv). Cisco pre-emptively argued the Fintiv factors in § VI of the petition ("The Board Should Reach the Merits"), conceding "the early stage of the litigation and uncertainty regarding the trial date," and noting it "filed this petition within one month after Patent Owner narrowed the set of asserted claims in the co-pending district court litigation" — the classic diligence rationale and the classic Fintiv fact pattern (a parallel W.D. Tex./C.D. Cal. campaign against nine defendants to be tried separately).
  2. Merits denial under § 314(a). Google Patents labels it "Not Instituted – Merits," which — if that label is reliable — would mean the panel was not persuaded of a reasonable likelihood on Kasami alone.
  3. § 325(d) / prior-art-considered. Possible but not evidenced in what I retrieved.
     If you are relying on why it was denied, pull the decision from PTAB E2E before you rely on any of the three.
• Final Written Decision: None issued. There is accordingly no claim-level verdict to report. Claims 15–22 and 30–35 were neither canceled nor sustained; claims 1–14, 23–29, and 36+ were never challenged and remain wholly untested at the PTAB.
• Settlement / termination: No settlement and no adverse-judgment termination is indicated. The proceeding ended by denial of institution, which is the Board's own act, not a party resolution. (No confidential settlement terms exist to report.)
• Appeal: None. A denial of institution is not an appealable final decision under 35 U.S.C. § 319 / 28 U.S.C. § 1295(a)(4)(A) — review, if any, lies in a mandamus petition, and I found no mandamus filing. The earlier section of this analysis also searched the Federal Circuit's September 2026 argument calendar and 2026 dockets and found no appeal involving XR/Vivato or the '939. Treat "no appeal" as a negative search result, not a verified absence; a direct PACER/CM-ECF query should confirm.
• Defensive value: Mixed, and the reason matters. On the positive side for a defendant today: the challenged claims survived the only petition ever filed against them — nothing is canceled, so there is no "claim 15 is dead, stop asserting it" argument available. On the negative side for a defendant: because institution was denied, § 315(e)(2) estoppel never attached, and the denial carries no issue-preclusive effect — a defendant is free to file a fresh petition against claims 15–35 on the same or different art (subject only to § 315(b)'s one-year bar running from service of an infringement complaint, and to the Director's Fintiv/§ 325(d) discretion). The corollary for the patent owner is equally important: it got zero adjudicated validity findings, so nothing about the '939's validity has been judicially settled in its favor either.
• Primary sources:
  • PTAB docket mirror (filing date, termination, panel, status, TC/AU): https://gaeflexstaging-dot-docketupdate.appspot.com/cases/PTAB/IPR2022-00958/Cisco_Systems_Inc._v._XR_Communications_LLC_dba_Vivato_Technologies/
  • Petition (full text, claim charts, Ground 1), CourtListener Ex. 11 to Doc. 81: https://www.courtlistener.com/docket/67349582/81/12/xr-communications-llc-dba-vivato-technologies-v-att-inc/
  • Petition PDF: https://storage.courtlistener.com/recap/gov.uscourts.txed.[222063](/patent/222063)/gov.uscourts.txed.222063.81.12.pdf
  • (Not yet retrieved — needed): the Decision Denying Institution itself, via PTAB E2E / PTAB Decisions for IPR2022-00958.

Unresolved lead — "Defendants' IPR on the '939 patent" (no proceeding number retrieved)

Do not treat this as a proceeding; treat it as a to-do. The E.D. Tex. Joint Claim Construction and Prehearing Statement (Doc. 76 / Doc. 4-3 filing, June 2024) lists, as Plaintiff's extrinsic evidence for the '939 terms:

"[P]etition and any other filings in IPR2022-00958; Defendants' IPR on the '939 patent; and exhibits thereto."

That phrasing — "Defendants' IPR on the '939 patent," distinguished from IPR2022-00958 — suggests a second, later IPR petition against the '939 filed by the AT&T/Verizon/T-Mobile defendants and/or the Ericsson/Nokia intervenors (all of whom are sophisticated, repeat IPR filers who jointly petitioned in other matters, e.g., IPR2024-00137 re the '888 patent). I could not confirm its existence, number, filing date, or disposition, and I will not invent a proceeding number. Note for the reader: the IPR2024-00314 repeatedly cited in the same docket is against the '369 patent, not the '939, and the citation of it in the same exhibit tables is a plausible source of confusion.

Action: query PTAB E2E by patent number 8,289,939 and by petitioner name (AT&T Services; Cellco/Verizon; T-Mobile; Nokia of America; Ericsson) for a petition filed in 2024–2025. If one exists and was denied, it belongs in this table; if it was instituted, then there is an active trial with a statutory 1-year FWD deadline that this analysis does not currently capture — which would materially change the defensive posture.

Strategic summary

Claim-by-claim status. No claim of U.S. 8,289,939 has been canceled, amended, disclaimed, or held unpatentable in any AIA trial. The only claims ever put at issue were claims 15–22 and 30–35, and they emerged from IPR2022-00958 intact by virtue of the denial of institution, not by adjudication. Everything else — claims 1–14, 23–29, and 36 and above — has never been challenged at the PTAB at all. So there is no "surviving-claims" list to give a defendant the comfort of a narrowed patent: the patent is as broad today as it was on 2012-10-16, less whatever narrowing the § 112 ¶ 6 construction imposes in district court. The most consequential narrowing of this patent is happening not at the PTAB but in the E.D. Tex. claim construction — where "signal transmission/reception coordination logic" was held means-plus-function and tied to Figures 7/12 (and arguably 13) algorithmic structure, over Vivato's objection (Doc. 99; Vivato's partial objection at Doc. 113/115). For a defendant, that construction is the real case-dispositive lever, and it is not a PTAB outcome.

Estoppel landscape. This is the single most important point for a defendant being asserted against today: denial of institution generates no estoppel. Section 315(e)(2) bars a petitioner (and its privies) from raising in a civil action any ground it "raised or reasonably could have raised" only after a final written decision — and the Board never issued one here. Two practical consequences follow. First, Cisco and Cisco's privies are not estopped; nor are the E.D. Tex. defendants estopped by anything Cisco did, because estoppel is petitioner-specific and, in any event, never attached. Second, the Kasami ground is not "used up." A defendant can file a fresh petition against claims 15–35 on Kasami (or on the better-structured Kasami + 802.11-1999 and/or Kasami + a reception-triggered restraint reference combination), and can add claims 1–14 and 36+ that were never reached. The live constraints are instead: (a) § 315(b) — one year from service of the complaint (the 2025 E.D. Tex./W.D. Tex. complaints against AT&T, Verizon, T-Mobile and others filed 2025-07-08 start or have started those clocks); (b) discretionary denial risk under § 314(a)/Fintiv and § 325(d), which is exactly what appears to have ended IPR2022-00958 and will be argued again; and (c) § 325(d) — Kasami itself was never "considered by the Office" during prosecution, so a repeat-Kasami petition is not automatically a § 325(d) loser, but the Board may still weigh the prior denial.

Pattern signals. (i) No repeat-petitioner pattern on the '939: only one petition has ever been filed against it, by Cisco, and Cisco did not re-file. (ii) No defensive aggregator sits in this chain — the earlier section's suggestion that Unified Patents filed IPR2022-00958 is contradicted by the docket, which captions the petitioner as Cisco Systems, Inc.; the "Unified" reference in the Google Patents litigation table appears to be a data-source artifact (Unified's litigation dataset licensed to Google Patents). Treat the petitioner as Cisco. (iii) Patent owner is a minimal PTAB appellant — no FWD here to appeal, and no '939 appeal exists; XR's Federal Circuit activity in this family (e.g., XR Commc'ns v. D-Link, Nos. 2022-1785 et al.; XR Commc'ns v. ARRIS, 2023 WL 3529830) has concerned sibling patents. (iv) Sibling-patent IPRs are active and separate: IPR2018-00762 ('231), IPR2022-00613 and IPR2024-00868 ('511, the latter by Ericsson), IPR2022-01155 and IPR2024-00613 ('235), and IPR2024-00314 ('369, denied institution 2024-07-15). None of these touch the '939, but they demonstrate that the E.D. Tex. defendants and intervenors are active, capable IPR petitioners — which is precisely why the "Defendants' IPR on the '939 patent" lead is credible and worth chasing. (v) Procedural tell: Cisco filed the '939 petition within one month of the patent owner narrowing asserted claims in the C.D. Cal. litigation — a diligence posture, and a signal that the asserted-claim set is a moving target the patent owner manages to avoid IPR exposure.

Recommended next steps

1. Do not tell a client "the '939 has survived two IPRs and is hardened" — and do not tell them "claims 15–22 and 30–35 were canceled." Neither is true. The accurate statement is: one IPR was filed; institution was denied; no claim has been adjudicated unpatentable; and no estoppel attached. If a demand letter from XR/Vivato cites claims 15–35 (the asserted set — see the infringement contentions in E.D. Tex., which chart claims 15, 17, 20–22, 30, 33–35), those claims are live and un-canceled; there is no FWD to quote.
2. Retrieve the IPR2022-00958 Decision Denying Institution from PTAB E2E (search by proceeding number or patent 8,289,939). Determine whether the denial was discretionary (§ 314(a)/Fintiv or § 325(d)) or on the merits. This single fact controls your petition strategy: a merits-based denial means the Kasami-as-sole-reference theory is weak and you must bring a multi-reference obviousness case; a discretionary denial means the merits were never reached and a well-timed petition (with the § 314(a) Fintiv factors now cured by the January 2026 dismissal-with-prejudice in 2:23-cv-00202) has a genuine shot.
3. Resolve the "Defendants' IPR on the '939 patent" lead referenced in the E.D. Tex. Joint Claim Construction Statement. Search PTAB E2E for petitions by AT&T Services / Cellco Partnership (Verizon) / T-Mobile / Nokia of America / Ericsson against 8,289,939 filed in 2024–2025. If such a petition exists and was instituted, there is an active trial you must monitor against the statutory deadlines — institution decision due ~6 months from filing, Final Written Decision due no later than 12 months from institution (extendable up to +6 months for good cause), and an oral hearing typically ~2–3 months before the FWD. If it was denied, add it to the table above; if no such petition exists, the exhibit's phrase is likely a drafting artifact and this lead can be closed.
4. Run the § 315(b) calculus now. For the 2025 complaints (E.D. Tex. 2:25-cv-00697/-698/-699, filed 2025-07-08; 2:25-cv-01253; W.D. Tex. 7:25-cv-00590/-591) the one-year bar has already run or is running. For the 2:26-cv-00001 filing and any 2026 service, there may still be a window.
5. If you file, expect a discretionary-denial fight, and prepare for it in the petition itself — stipulate out of the overlapping grounds (Sand Revolution–style), address Fintiv factors 1–6 on the current (post-dismissal) district-court posture, and pre-empt § 325(d) by showing Kasami and any 802.11 references were not substantively considered during prosecution (they were not — the Office rejected the claims over different art). Note also that the E.D. Tex. district court's § 112 ¶ 6 construction of "signal transmission/reception coordination logic" is a validity-neutral but claim-narrowing point that can and should be leveraged separately in the litigation.
6. Escalate the § 112 ¶ 6 / indefiniteness thread in the district court, not the PTAB. The E.D. Tex. court held the '939 "signal transmission/reception coordination logic" term means-plus-function, identified Figures 7/12 (and Vivato argues Figure 13) algorithms as corresponding structure, and noted apparent tension with claim 15's "ongoing" second-signal limitation on the present-tense "is receiving" language. That is a § 112 exposure the PTAB cannot award you in an IPR (no § 112 grounds in an IPR) but which is already teed up in E.D. Tex. and was the subject of Vivato's partial objection at Doc. 113/115. It is the most promising non-PTAB path.

Sources cited (all retrieved unless noted):

What I could not verify, restated: (a) the ground on which IPR2022-00958 was denied; (b) whether a second '939 petition by the E.D. Tex. defendants exists; (c) a direct PACER/CAFC docket confirmation that no appeal or mandamus was filed. I have not fabricated any proceeding number, claim-level outcome, or panel quotation, and I have not asserted a Final Written Decision where none issued.

I'll research the USPTO assignment record for US 8,289,939, focusing on reel/frame, conveyance type, and correspondent of record.

Let me try to pin down the actual reel/frame records for app 10/700,342 and the Vivato/XR assignment correspondents.

I hit the tool-call limit mid-research. I'll report exactly what I verified and be explicit about the two fields I could not retrieve (reel/frame and correspondent of record). I will not invent reel/frame numbers or attorney names.

Assignment reconstruction — U.S. Patent No. 8,289,939

Scope and sourcing caveat (read first). My assigned primary source — the USPTO Patent Assignment Center (https://assignmentcenter.uspto.gov/, mirror at https://assignment.uspto.gov/patent/index.html) — returned no accessible page content in this session. What I did retrieve is (a) the Google Patents "Legal Events" assignment list for US8289939B2, which is populated from the USPTO assignment record (assignor, assignee, and conveyance type are given; reel/frame and correspondent are not), (b) corroborating docket/exhibit material in E.D. Tex. 2:23-cv-00202, and (c) a USPTO PTAB petition exhibit that reproduces the recorded assignment cover sheets themselves (confirming the documents are on file at the USPTO). I confirmed eight assignee-change events after filing. I could not retrieve a single reel/frame number or a single correspondent name/address for this patent. Those fields are marked "NOT RETRIEVED" below, and I explain what that does to signal #3.

Inventors

All four are listed on the face of the patent and all four appear as assignors on the recorded assignment of inventors' interest to Vivato, Inc., Portland, OR, recorded 2004-07-09 (Google Patents legal-events entry; assignee residence "Portland, OR" confirmed from the recorded cover sheet reproduced in a USPTO PTAB petition exhibit: https://ptacts.uspto.gov/ptacts/public-informations/petitions/[1555050](/patent/1555050)/download-documents?artifactId=Fp6ZJ8QaygZi-Z1mS5DU_hXM9S_Bt9M0T1T-3rlSaAIBkW0Ml6dbo94).

Unusual patterns — what I can and cannot say.

• Confirmed: this is an all-inventors-assign-to-single-corporate-assignee record with no retained inventor interest and no government-interest indication — the normal pattern for a venture-backed hardware startup.
• Confirmed: the original assignee was distressed within ~3 years of filing (asset-purchase transfer in 2006; see below).
• NOT verified — do not rely on this as a finding: the prompt's suggested pattern ("all inventors departing the original assignee within 12 months of filing"). I found no dated evidence of any inventor's departure, and I will not infer it. One adjacent data point I did see, in an XR venue-transfer filing, is that James Brennan was identified by XR as a willing nonparty witness, alongside Siavash Alamouti, out of roughly 11 named inventors across the asserted patents (https://ptacts.uspto.gov/ptacts/public-informations/petitions/[1550096](/patent/1550096)/download-documents?artifactId=6ppj4DOAwqEtjXitjuzAtNrIzfBAMGAh4ULgZudxP0NjdRqMQ6o5stk). That is a litigation-witness fact, not a departure date.

Original assignee

Vivato, Inc. (Portland, OR; also associated with San Francisco), the entity to which all four inventors assigned and the applicant of record for parent application 10/700,342.

• Primary line of business (at the time): wireless LAN infrastructure — a beamforming / switched-beam Wi-Fi "access station." This is a real, shipped product: the Vivato Switch was a phased-array, multi-beam outdoor/indoor Wi-Fi base station marketed in the early-to-mid 2000s. A university deployment evaluation of the actual product is in the public record (Vivato Switch Evaluation, Florida State University OTC, comparing a single Vivato Switch against 6–22 conventional APs: http://www.otc.fsu.edu/pdf/Vivato_Switch_Evaluation.pdf). This matters because it establishes that the '939's original assignee did ship hardware embodying the claimed multi-beam/multi-access-point architecture.
• Current status: defunct. Vivato ceased operating; its assets were transferred out in 2006, and the patent was ultimately taken from the successor entities by secured-lender foreclosure (a "Limited Judgment of Foreclosure" and a "Sheriff's Certificate of Judicial Sale" — see timeline). I have no verified date of corporate dissolution, and I am not asserting a Chapter 7/11 case number because I did not retrieve one.
• Litigation characterization of record: defendants in the earlier campaign described XR as "adopting the name of Vivato, Inc., a failed wireless technology company" and "attempt[ing] to resurrect Vivato, Inc.'s patent holdings" (Defendants' Opening Claim Construction Brief, C.D. Cal. 8:17-cv-00596, reproduced at https://www.docketalarm.com/cases/PTAB/IPR2018-00762/CISCO_SYSTEMS_INC._v._XR_Communications_LLC_d-b-a_Vivato_Technologies/docs/03-15-2018-Petitioner/Exhibit-1013-CSCO_1013___Defendants_Opening_CC_Brief.pdf?download=true). That is a party's characterization, not a finding — but it is on the record.

Assignment timeline

Every entry below is a recorded assignment event from the USPTO-derived Google Patents legal-events record. Reel/frame and correspondent were NOT RETRIEVED for any entry — the Assignment Center was unreachable in this session. Where I give a context label, it is my inference clearly labeled as such.

No entry below is fabricated; each corresponds to a listed recordation event with a stated assignor, assignee, and conveyance type.

1. 2003-11-03 (application filed) — recordation date not applicable (filing event, not an assignment)

   • Conveyance: n/a — application 10/700,342 filed by the inventors / Vivato, Inc.
   • Assignor / Assignee: n/a
   • Correspondent: NOT RETRIEVED
   • Context: initial filing; priority claimed to provisionals 60/423,702 and 60/423,696 (both 2002-11-04).

2. Executed ~2003–2004 / recorded 2004-07-09 — Reel/Frame NOT RETRIEVED

   • Conveyance: Assignment of Assignors' Interest (see document for details)
   • Assignor: Brennan, James; Casas, Eduardo; Jose, Bobby; Mehrotra, Praveen (the four inventors)
   • Assignee: Vivato, Inc., Portland, OR
   • Correspondent: NOT RETRIEVED — flagged: this is the original prosecution-side assignment; identifying the recording firm here is the usual way to match the patent to Vivato's later estate filings.
   • Context: inventors → operating company (standard startup capitalization of IP).

3. Executed 2006 / recorded 2006-09-21 — Reel/Frame NOT RETRIEVED

   • Conveyance: "First Amendment to Asset Purchase Agreement"
   • Assignor: Vivato, Inc.
   • Assignee: Wayout Wireless, LLC
   • Correspondent: NOT RETRIEVED
   • Context: stress/asset sale — the operating company's IP moving to a buyer under an amended asset-purchase agreement. My inference: Vivato was winding down.

4. Executed 2007 / recorded 2007-08-06 — Reel/Frame NOT RETRIEVED

   • Conveyance: Change of Name (see document for details)
   • Assignor: Wayout Wireless, LLC
   • Assignee: Vivato Networks, LLC
   • Correspondent: NOT RETRIEVED
   • Context: change of name only — Wayout Wireless, LLC renamed itself "Vivato Networks, LLC." (Note this is a pure name change, not a transfer of ownership; it is why the assignee reverts to a "Vivato"-branded name.)

5. Executed 2007 / recorded 2007-11-30 — Reel/Frame NOT RETRIEVED

   • Conveyance: Security Agreement
   • Assignor: Vivato Networks, Inc. (formerly Vivato Networks, LLC)
   • Assignee: Aequitas Capital Management, Inc.
   • Correspondent: NOT RETRIEVED
   • Context: securitization / collateral — not an ownership transfer. This records a lender's security interest in the patent. Important for the chain: it documents that Vivato Networks, Inc. pledged the '939 as collateral.

6. Executed 2007 / recorded 2007-12-07 — Reel/Frame NOT RETRIEVED

   • Conveyance: Assignment of Assignors' Interest (see document for details)
   • Assignor: Vivato Networks, LLC
   • Assignee: Vivato Networks Holdings, LLC
   • Correspondent: NOT RETRIEVED
   • Context: internal restructuring — IP moved into a holding vehicle (the classic pre-foreclosure / pre-sale holding structure).

7. Executed 2009 / recorded 2009-05-06 — Reel/Frame NOT RETRIEVED

   • Conveyance: Loan Assignment and Acceptance
   • Assignor: Aequitas Capital Management, Inc.
   • Assignee: Aequitas Equipment Finance, LLC
   • Correspondent: NOT RETRIEVED
   • Context: securitization — the secured lender's position (and the collateral file) rotated within the Aequitas family. Again, a financing-interest event, not a sale.

8. Executed 2009 / recorded 2009-05-06 — Reel/Frame NOT RETRIEVED

   • Conveyance: Limited Judgment of Foreclosure
   • Assignor: Vivato Networks, Inc.
   • Assignee: Aequitas Equipment Finance, LLC
   • Correspondent: NOT RETRIEVED
   • Context: foreclosure — the lender reduced its collateral claim to judgment against the borrower.

9. Executed 2009 / recorded 2009-06-05 — Reel/Frame NOT RETRIEVED

   • Conveyance: Sheriff's Certificate of Judicial Sale
   • Assignor: Vivato Networks Holdings, Inc. (formerly Vivato Networks Holdings, LLC)
   • Assignee: Aequitas Equipment Finance, LLC
   • Correspondent: NOT RETRIEVED
   • Context: judicial sale — the patents were taken through a sheriff's sale on the foreclosure judgment. This is the operative step that broke the Vivato estate's ownership.

10. Executed 2009 / recorded 2009-12-23 — Reel/Frame NOT RETRIEVED

    • Conveyance: Assignment of Assignors' Interest (see document for details)
    • Assignor: Aequitas Equipment Finance, LLC
    • Assignee: XR Communications, LLC (d/b/a Vivato Technologies)
    • Correspondent: NOT RETRIEVED — this is the single most important correspondent to obtain: it identifies who packaged the Vivato patent estate for assertion.
    • Context: transfer-to-asserter — the foreclosing lender sold the portfolio to the entity that now asserts it. The recording date (2009-12-23) precedes every enforcement campaign (2017, 2021, 2023, 2025) by years.

Chain-of-title summary (ownership only; financing entries excluded):
Vivato, Inc. → Wayout Wireless, LLC (asset purchase) → Vivato Networks, LLC (name change) → Vivato Networks Holdings, LLC (assignment) → Aequitas Equipment Finance, LLC (foreclosure + sheriff's sale) → XR Communications, LLC (2009-12-23).

Where to verify: USPTO Assignment Center, search by patent number 8289939 — https://assignmentcenter.uspto.gov/ (legacy UI: https://assignment.uspto.gov/patent/index.html). The recorded cover sheets for at least the Wayout Wireless → Vivato Networks step are reproduced verbatim in a public USPTO PTAB petition exhibit: https://ptacts.uspto.gov/ptacts/public-informations/petitions/1555050/download-documents?artifactId=Fp6ZJ8QaygZi-Z1mS5DU_hXM9S_Bt9M0T1T-3rlSaAIBkW0Ml6dbo94.

Timeline diagram

timeline
    title Ownership of US 8289939
    2002 : Provisionals filed Nov 4
    2003 : Nonprovisional app filed Nov 3
    2004 : Inventors assign to Vivato Inc
    2006 : Vivato Inc assets to Wayout Wireless
    2007 : Wayout renamed Vivato Networks
         : Security agreement to Aequitas
         : IP moved to Vivato Networks Holdings
    2009 : Loan assigned within Aequitas
         : Foreclosure judgment entered
         : Sheriff sale of patents
         : Assigned to XR Communications LLC
    2012 : Patent issued Oct 16
    2017 : First campaign suit vs D-Link group
    2022 : Cisco IPR denied institution
    2025 : New suits vs AT and T Verizon T Mobile

NPE / troll-pattern signals

1. Shell-entity transfer — PRESENT.
   The patent left an operating company that shipped a real product (Vivato, Inc. / the Vivato Switch) and passed through a renamed asset-holding vehicle (Wayout Wireless, LLC → Vivato Networks, LLC, recorded 2007-08-06, "Change of Name") and a holding LLC (Vivato Networks Holdings, LLC, recorded 2007-12-07) before landing at XR Communications, LLC (recorded 2009-12-23). XR Communications is a licensing vehicle that does not ship the claimed apparatus. Corroborating evidence that these are single-purpose holding entities rather than operating businesses: the conveyance types themselves ("First Amendment to Asset Purchase Agreement," 2006-09-21; "Change of Name," 2007-08-06) plus the absence of any product-side assignment or license to an operating manufacturer anywhere in the record. Caveat: I could not retrieve the registered-agent addresses, so the "registered-agent service / single-member LLC" tell is NOT RETRIEVED — the signal is supported by the operating-company→holding-vehicle movement and the conveyance types, not by address evidence.

2. Known asserter in the chain — PRESENT.
   The record holder since 2009-12-23 is XR Communications, LLC d/b/a Vivato Technologies, which appears as the "Patent Asserter" in the Stanford NPE Litigation Database for cases asserting this patent (e.g., https://npe.law.stanford.edu/case/[307184](/patent/307184) and https://npe.law.stanford.edu/patent/[8199724](/patent/8199724)). It is not on the specific named list in the prompt (Acacia, Marathon, IV, IPNav, Wi-LAN, Mosaid/Conversant, Vringo, Pendrell, Innovatio, MPHJ, Lumen View, Round Rock, Document Generation, Spangenberg, et al.), so I am not claiming a match to those. The finding is narrower and still solid: XR/Vivato is a recognized high-frequency patent asserter by the standard public asserter directories. Enforcement footprint I can cite: 2017 campaign against D-Link, Belkin, Aruba, Netgear, Ruckus, Ubiquiti, ASUS, Cisco, Extreme (C.D. Cal. 8:17-cv-00596); 2021 wave (Ruckus N.D. Cal. 3:21-cv-04679; Cisco W.D. Tex. 6:21-cv-00623; Samsung 6:21-cv-00626; Microsoft 6:21-cv-00695); 2023 wave against AT&T (E.D. Tex. 2:23-cv-00202; '939 listed as an asserted patent on the AO 120, holder "XR Communications, LLC"); and the 2025 wave against AT&T/Verizon/T-Mobile (E.D. Tex. 2:25-cv-00697/-698/-699) with the '939 again listed (https://storage.courtlistener.com/recap/gov.uscourts.txed.[222063](/patent/222063)/gov.uscourts.txed.222063.123.7.pdf).

3. Repeat correspondent across the chain — UNVERIFIABLE (not a finding either way).
   This is the signal the prompt weights most heavily, and it is precisely the one I could not test: no correspondent-of-record field was retrievable for any of the nine recorded events, because the Assignment Center was inaccessible in this session. I am reporting this as insufficient data, not as "not present." What to do: query the Assignment Center by patent number and record the correspondent on each of the nine entries (the 2006-09-21 Wayout, 2007-12-07 Holdings, and 2009-12-23 XR entries are the highest-value ones). The tell to look for is a single attorney/firm appearing on the 2007 restructuring steps and the 2009 XR transfer — that would link the bankruptcy/foreclosure packaging to the asserter in the same hands.
   Adjacent, clearly-labeled evidence that is NOT the correspondent-of-record signal: XR's litigation/prosecution-side counsel of record has been named in filings as Vlad Teplitskiy, Glen Nuttall, and Nicholas Transier (https://ptacts.uspto.gov/ptacts/public-informations/petitions/1550096/download-documents?artifactId=6ppj4DOAwqEtjXitjuzAtNrIzfBAMGAh4ULgZudxP0NjdRqMQ6o5stk). These are attorneys prosecuting/litigating the asserted patents, which is a different role from the assignment-recording correspondent. I flag the recurrence but explicitly do not conflate the two.

4. Cascading transfers — PRESENT (strong).
   Eight assignee-changing events after the 2004 inventors' assignment, with five recorded transfers between September 2006 and December 2009 — and four of them inside an eight-month window (2009-05-06 loan assignment, 2009-05-06 foreclosure judgment, 2009-06-05 sheriff's sale, 2009-12-23 transfer to XR Communications). The consecutive-LLC pattern (Wayout Wireless, LLC → Vivato Networks, LLC → Vivato Networks Holdings, LLC) inside ~16 months, followed by the Aequitas takedown, is the textbook cascade. Whether the assignees share a common correspondent address or common principals is NOT VERIFIABLE here for the same reason as signal #3.

5. Pre-litigation transfer — NOT PRESENT.
   The last ownership transfer of record is 2009-12-23 (to XR Communications). The first suit naming the '939 that I can date is the 2017 C.D. Cal. campaign — roughly seven years later. No assignment is dated within six months before any asserted suit, and no re-transfer accompanied the 2021, 2023, or 2025 waves. The chain was not re-arranged to set venue for any particular case; the venue story (California HQ asserter filing in E.D. Tex. / W.D. Tex.) was litigated directly on the transfer motions instead (see XR's venue record at petitions/1550096).

6. Bankruptcy fire-sale — PRESENT as a distressed/foreclosure sale, with a precision caveat.
   The patents were taken by a secured creditor through a "Limited Judgment of Foreclosure" (recorded 2009-05-06) and a "Sheriff's Certificate of Judicial Sale" (recorded 2009-06-05), on the strength of a Security Agreement recorded 2007-11-30 to Aequitas Capital Management, Inc. That is a foreclosure / UCC Article 9-style enforcement and judicial sale, which is functionally the distressed-asset disposition the prompt describes. I am not labeling it a Chapter 7 or Chapter 11 sale, because I did not retrieve a bankruptcy case number for Vivato and the record I have shows a lender remedy, not a bankruptcy-court sale. Both the secured party family (Aequitas Capital Management / Aequitas Equipment Finance) and the borrower-side entities (Vivato Networks, Inc./Holdings) appear in the chain.

7. Privateering — NOT PRESENT.
   Privateering requires an operating company transferring to an NPE that sues the operating company's competitors on its behalf. Here the transferor side (Vivato, Inc.; Vivato Networks entities) was out of business at the time of the operative transfers, and the ultimate asserter (XR/Vivato) targets large carriers and equipment vendors (AT&T, Verizon, T-Mobile, Cisco, Samsung, Microsoft, Dell) rather than any set of entities the now-defunct Vivato competed with. There is no SEC-filing or Patent Progress/EFF evidence of an operating sponsor behind XR. Signal not present.

8. Defensive aggregator (anti-NPE) — NOT PRESENT.
   The chain terminates at XR Communications, LLC, an asserter — not at RPX, AST, LOT Network, Unified Patents, or OIN. I specifically checked the one plausible confusion point: Unified Patents appears in this patent's public record only as a data-source attribution on the Google Patents page ("Unified Patents Litigation Data"/"Unified Patents PTAB Data"), not as an owner or a petitioner. The single IPR on this patent (IPR2022-00958) was filed by Cisco Systems, Inc., not by a defensive aggregator. No settlement, license, or assignment to a defensive aggregator is recorded. The patent is not neutralized.

Verdict

NPE — high confidence.

Two or more strong signals are present on the face of the record: (i) a shell-entity / holding-vehicle transfer chain in which the '939 moved from an operating company that shipped hardware (Vivato, Inc.) through renamed single-purpose vehicles — Wayout Wireless, LLC recorded 2006-09-21, renamed Vivato Networks, LLC recorded 2007-08-06, IP moved to Vivato Networks Holdings, LLC recorded 2007-12-07 — and out to a licensing entity, XR Communications, LLC, recorded 2009-12-23; (ii) a known high-frequency asserter as record owner, XR Communications, LLC d/b/a Vivato Technologies, listed as the "Patent Asserter" in the Stanford NPE Litigation Database and shown asserting this same patent across the 2017, 2021, 2023 and 2025 enforcement waves; and (iii) a cascading/distressed cascade of five recorded transfers between 2006-09 and 2009-12, culminating in a foreclosure judgment (2009-05-06) and sheriff's judicial sale (2009-06-05) to the foreclosing lender Aequitas Equipment Finance, LLC, which then sold to XR.

The one signal I could not evaluate — and the one the prompt flags as the best tell — is the repeat correspondent: reel/frame and correspondent-of-record were not retrievable in this session, so signal #3 is reported as insufficient data, not as "not present." Verify via the USPTO Assignment Center at https://assignmentcenter.uspto.gov/ by searching patent number 8289939, and prioritize capturing the correspondent on the 2007-12-07 (Holdings) and 2009-12-23 (XR Communications) entries; if the same recording attorney or firm appears on both, that converts the strongest remaining unknown into an additional confirmed signal.

Sources: Google Patents family/legal-events record for US8289939B2 — https://patents.google.com/patent/US8289939/en; USPTO PTAB petition exhibit reproducing the recorded assignment cover sheets — https://ptacts.uspto.gov/ptacts/public-informations/petitions/1555050/download-documents?artifactId=Fp6ZJ8QaygZi-Z1mS5DU_hXM9S_Bt9M0T1T-3rlSaAIBkW0Ml6dbo94; Stanford NPE Litigation Database — https://npe.law.stanford.edu/case/307184 and https://npe.law.stanford.edu/patent/8199724; E.D. Tex. 2:23-cv-00202 AO 120 and invalidity contentions — https://storage.courtlistener.com/recap/gov.uscourts.txed.222063/gov.uscourts.txed.222063.123.7.pdf; Vivato Switch product evaluation — http://www.otc.fsu.edu/pdf/Vivato_Switch_Evaluation.pdf; USPTO Assignment Center (verification target) — https://assignmentcenter.uspto.gov/.

Honesty note on the gaps: I did not fabricate any reel/frame number or correspondent name. If it would help, a follow-up pass against the Assignment Center — searching by patent number 8289939, and cross-searching assignee "Vivato Networks" and "Aequitas Equipment Finance" — should surface the nine reel/frame pairs and their correspondents, which would close the only material hole in the analysis above.

I'll search the USPTO-record prior art (the "References Cited" section) for US 8,289,939. Let me run several targeted lookups.

Let me pull the actual citation lists from patent-record sources.

Let me try to retrieve the front-page reference list directly.

Prior Art Analysis — U.S. Patent No. 8,289,939 (literal ID: 8289939)

Analysis date: April 26, 2026 · Tool available: web search only (no direct PatentCenter/ODP API access in this session)

0. Scope discipline and a required disclosure about sourcing

Identifier discipline. I searched the literal number 8,289,939. Search engines returned many near-neighbours — U.S. 7,331,939 (Fangrow, medical), U.S. 5,713,939 (Nedungadi, medical), U.S. 10,255,575 / US 9,231,711 (which cite 8289939), and various "939 Citations" pages. None of those is this patent and I have excluded all of them.

Disclosure you need before reading the tables. You asked me to "look at each patent citation for 8289939." The authoritative source for that is the printed front page of the patent — the (56) References Cited block — which I could not retrieve in full this session. The Google Patents text extract supplied to me carries classifications, definitions, abstract, description and legal events, but not the (56) citation table; my attempts to pull the front-page list (Justia citation table, FPO, patentimages PDF) returned the specification and claims but not the (56) block. Rather than reconstruct that list from memory — which would risk manufacturing numbers — I report below:

• (A) the bibliographic record I did confirm,
• (B) the reference set that is verifiably of record against the '939 patent in third-party proceedings (IPR2022-00958 and E.D. Tex. 2:23-cv-00202), where I can cite the actual documents, and
• (C) an explicit list of what I could not verify.

Where a claim-text detail below contradicts or fills a gap flagged in the earlier generated sections, I say so. One such item: the earlier "Patent summary" section flagged that claims 2–14 were not retrievable. I have now retrieved claims 1–15 from the Justia record, and reproduce claim 1 verbatim in §2.

1. Confirmed bibliographic record (USPTO data, as mirrored by Google Patents / Justia)

Critical dates for §102 purposes (pre-AIA):

2. The claim set the references must be measured against

Independent claim 1 (verbatim, from the granted patent; note the source's own typographical artefacts are reproduced literally):

"1. An apparatus comprising:
a wireless input/output (I/O) unit that is configured to establish a plurality of access points; and
signal transmission/reception coordination logic that is capable of ascertaining, by monitoring the plurality of access points for received signals, that a first access point of the plurality of access points is receiving a first signal and that is adapted to restrain at least two other access points of the plurality of access points from transmitting signal responsive to the ascertaining that the first access point is receiving the first signal;
wherein the signal transmission/reception coordination logic restrains at least one other access point of the plurality of access points from transmitting the other signal on a first channel responsive to the ascertaining that the access point of the plurality of access points is receiving the signal on a second different channel."

Dependents retrieved this session (1–14): 2 co-located APs · 3 IEEE 802.11 · 4 uplinked packet · 5 portion of an uplinked packet · 6 preamble · 7 downlink restrained · 8 restraint persists while receiving · 9 AP = communication beam · 10 AP = MAC/baseband-unit pair · 11 coordination logic = MAC coordinator logic · 12 MAC coordination logic links two or more access stations · 13 logic affects a baseband unit · 14 logic affects an RF part.

Other independents: claim 15 (multi-reception / "ongoing" second signal, restrain a third AP on a third channel, prevent degradation to first and second signals), claim 23, claim 30 (cross-channel restraint). Claims 15–22 and 30–35 were the set challenged in IPR2022-00958. Pre-grant publication US 2004/0223476 A1 also carried system claims 79 and method claims 80 and 86 — I have not confirmed which of those survived into the granted set, so I do not map prior art to them below.

3. The reference set verifiably of record against the '939 patent

3.1 How to read this table

Two populations of references exist against this patent, and conflating them is the most common error in this family:

• Population A — references cited on the face of the patent (examiner/applicant IDS). I could not retrieve this population. See §5.
• Population B — references cited by third parties against the patent (IPR petitioner; E.D. Tex. defendants). This is what I can verify, from primary documents.

Everything in the table below is Population B unless marked otherwise.

One reference I verified independently: US 6,456,844 B1 — Parantainen ("Method for admission control in interference-limited cellular radio network," Nokia; PCT filed 1997-12-18; issued 2002-09-24) → §102(b). It is cited in the contentions' channel-selection group.

4. Reference-by-reference analysis, with §102 claim mapping

4.1 US 7,158,501 B2 — Kasami et al. (the most relevant reference on this record)

Full citation. U.S. Patent No. 7,158,501 B2, "Wireless communication apparatus," inventors Kasami et al., filed 29 May 2002, issued 2 January 2007; published counterpart US 2002/0181492 A1 (5 December 2002); JP priority JP 2001-160928 (29 May 2001); EP counterparts EP 1 263 168 A3 and EP 1 286 506 A3. Assignee: Toshiba.

Brief description (from the petition's charting of the reference itself). A base station with transmitter modules 12-1…12-3 and receiver modules 11-1…11-3 operating over a plurality of beams formed by an adaptive array antenna. A reception end detecting section 18 / reception time detection section 20 parses a "required time" field from a received packet and computes a maximum reception end time; a transmission enabling section 19 "maintains the transmitter modules 12-1 to 12-3 in a transmission disable state in the reception mode" and supplies a transmission-enable signal only "in response to the reception end signal." Kasami also discloses modules operating on the "substantially same channel or adjacent channel," treats each directed beam as a distinct spatial channel in SDMA, and — in a separate embodiment — has co-located wireless module sections 102-1/102-2 exchange a "reception information notifying/acquisition" indication, with module 102-2 "so controlled as to transmit no radio signal" because "a transmission signal of the wireless module 102-1 is not outputted as an interference signal."

§102 posture — this is the cleanest point in the whole analysis. Kasami is available as §102(e)(2)/(e)(1) art on its U.S. filing date of 29 May 2002, which precedes every candidate priority date for the '939 (4 Nov 2002 or 3 Nov 2003). Two consequences:

1. The priority-date fight does not affect Kasami's availability. Even if defendants win their argument that the provisionals do not support the asserted claims and the effective date moves to 3 Nov 2003, Kasami still qualifies.
2. Note the Hilmer nuance: the earlier section's observation that Kasami carries a JP priority date of 29 May 2001 is interesting but legally irrelevant for §102(e) — foreign priority does not give a reference a §102(e) date. The operable date is the U.S. filing date, 29 May 2002. Anyone relying on the 2001 date is off by a year and by a doctrine.

Which claims does it potentially anticipate under §102?

But weigh this against the record: IPR2022-00958 was filed on Kasami alone, on §103 obviousness (not §102 anticipation), and the Board denied institution. Two implications: (i) no adjudicator has ever treated Kasami as an anticipating reference; and (ii) the Board was unpersuaded that Kasami reached the challenged claims even on the lower obviousness threshold. A §102 theory is therefore a larger ask than the one already rejected. The right reading is that Kasami is a §102(e) reference of record with strong §102 potential against narrow dependents and claim 30, contested against claims 1 and 15 — not a silver bullet. I could not retrieve the institution decision text, so I cannot tell you whether the denial turned on the "ongoing"/temporal limitation, the motivation-to-combine showing, or the §112 ¶ 6 construction step. That document should be pulled before anyone builds a theory on this reference.

4.2 US 7,042,860 B2 — Kasami; Obayashi

Citation. U.S. Patent No. 7,042,860 B2, Kasami & Obayashi, issued 9 May 2006. Listed in the E.D. Tex. invalidity contentions as exhibit B04 ("Kasami 860").

Description. A second Toshiba/Kasami reference in the same technical family as the '501 patent; the contentions place it in the "Restraining Transmission" group, i.e., it is used for the proposition that restricting transmission because of interference was known.

§102 posture. If its U.S. filing date precedes 4 Nov 2002, it is §102(e) art; if later, it is not prior art at all against a Nov. 2002 priority date. I did not verify its filing date this session, and I will not guess it. Claim mapping (conditional, filing date permitting): claims 7, 8, 13, 14 and, in combination with '501, the restraining element of 1/15/30. On its own it is a combination reference, not an anticipation reference — the contentions use it that way.

4.3 US 5,515,378 — Roy, III et al.

Citation. U.S. Patent No. 5,515,378, Roy, III et al., "Spatial division multiple access wireless communication systems," issued 7 May 1996, ArrayComm, Inc.

Description. A base station that uses an adaptive antenna array to form multiple simultaneous spatial channels (beams) and serves multiple remote users on the same frequency at the same time using spatial processing.

§102 posture. Issued 1996 → §102(b), unassailable as prior art regardless of the priority fight.

§102 claim mapping — and I want to be candid: Roy supports only the architectural preamble of claims 1/15/30 — a wireless unit establishing a plurality of access points / beams — and is the best reference of record for claim 9 (AP ↔ communication beam) and the "plurality of access points" element generally. It does not disclose ascertaining that one access point is receiving and restraining another access point's transmission responsive to that reception. Roy therefore does not anticipate claim 1, 15 or 30, and its presence on this list should not be mistaken for an anticipation case. It is a §103 reference (and the specification of the '939 itself equates access points with communication beams, which weakens a "different invention" rebuttal).

4.4 US 7,127,211 B1 — Hildebrand et al.

Citation. U.S. Patent No. 7,127,211 B1, Hildebrand et al., issued 24 October 2006. Listed as Cisco exhibit CISCO-1015.

Description. I could not verify this reference's title, assignee, filing date or disclosure content in this session. It appears in the petitioner's exhibit list alongside the claim-construction exhibits, but the exhibit list alone does not establish what the petitioner used it for. I am not going to characterise its teaching.

§102 posture. On its issue date alone it cannot be §102(a)/(b) art (2006 is after any asserted priority date); it can only be prior art under §102(e) if its underlying U.S. filing date precedes the '939's priority date, which I have not verified. Claim mapping: cannot be stated. Pull the exhibit from the PTAB/CourtListener record or the patent itself.

Flag for whoever verifies this: if US 7,127,211 turns out to be commonly owned with or a family member of the Vivato portfolio, its status as "prior art" against the '939 is non-trivial (pre-AIA §103(c) / common-ownership issues). That is a live question, not a settled one, and it should be checked before this reference is charted.

4.5 US 6,456,844 B1 — Parantainen

Citation. U.S. Patent No. 6,456,844 B1, "Method for admission control in interference-limited cellular radio network," Nokia; PCT filed 18 Dec. 1997; issued 24 Sept. 2002.

Description. Interference-threshold-based admission control with channel measurement and channel selection/reassignment. §102 posture: issued 2002-09-24 — before the priority date, so §102(b) if the provisional benefit holds at 4 Nov 2002 (24 Sept. 2002 < 4 Nov. 2001? No — 24 Sept. 2002 is after 4 Nov. 2001, so it is not §102(b); it is §102(a) art only if it predates the invention, or §102(e) as of its 1997 filing date). Claim mapping: the cross-channel restraint of claims 1 and 30 — but as a §103 reference. It is a cellular admission-control system, not a per-packet reactive restraint, so an anticipation theory is not credible.

4.6 The 802.11 sources (IEEE 802.11-1999; 802.11h proposal; Gast; O'Hara & Petrick)

Description. The 802.11 standard family supplies CSMA/CA, clear channel assessment (CCA) busy/non-busy, DCF timing, beacons and BSSID; the 802.11h proposal supplies dynamic channel selection / transmit power control.

§102 posture. IEEE 802.11-1999 → §102(b). The 802.11h draft date is unverified and matters: a 2003 draft is not prior art against a Nov. 2002 priority date.

§102 claim mapping. These sources are highly relevant to dependent claim 3 (IEEE 802.11 operation) and to the "constructive receive indicator → MAC CCA input" concept, because the '939 specification itself defines its own indicators in exactly these terms ("the receive indicators may comprise clear channel assessment (CCA) or busy/non-busy indications"; "the constructive receive indicators may comprise an indication for one or more predetermined inputs, such as a CCA or busy/non-busy input, of MACs"). But a standard that defines CCA within a single MAC does not disclose cross-access-point coordination — which is the entire inventive point. No anticipation of claims 1, 15 or 30. It is the natural secondary reference for claim 11 (MAC coordinator logic) and for a §103 theory.

4.7 A direction-of-citation caution

Search results surface 8289939 in the "Referenced Cited" tables of later patents — e.g., US 9,231,711 ("Interference management service for portable communication devices") lists "8289939 | October 16, 2012 | Jose et al." and later-dated IDS search strings (e.g., in the file history of US 10,255,575) also contain the number. Those are citations to the '939, not prior art for it. No later-issued patent can be §102 art against it. This is worth stating explicitly because it is an easy way to produce a false prior-art list in this family.

5. What I could not verify — read this before relying on the above

1. The complete (56) "References Cited" block from the front page of US 8,289,939 is not in my retrievable record this session. Your request was specifically for "each patent citation for 8289939," and I can only partially satisfy it. The honest answer is: I have the third-party-cited reference set (above) and not the examiner/applicant-cited set. To close this, pull:
   • the granted patent PDF front page (exhibit CISCO-1001 in IPR2022-00958 is a clean copy), or
   • the "Patent Citations" table at https://patents.google.com/patent/US8289939/en (present on the page, not in the text extract I received), or
   • Justia at https://patents.justia.com/patent/8289939, or
   • PatentCenter for application 10/700,342, "References Cited" tab.
2. Filing dates for US 7,042,860 (Kasami/Obayashi) and US 7,127,211 (Hildebrand) — unverified. Both are, or are not, §102(e) art depending entirely on those dates. Do not chart them without them.
3. Individual serial numbers for the contents' art-group labels (Reudink, AP-1000, Fujinami, Gibson, Roman, Katzela, Holma, Souissi, Johansson, Mansfield, Scherzer, Jaszewski, Hansen, Busch, McHenry, Gibbons, Proctor, Hamalainen, Watanabe, Sashihara) — not verified. I have deliberately supplied no presumed numbers. The earlier "Obviousness" section flagged the same gap; it is unresolved.
4. The text of the IPR2022-00958 institution decision — not retrieved. Without it, no one can say why Kasami failed at the threshold.
5. The B01–B26 claim charts in E.D. Tex. Doc. 123 — not retrieved (only the exhibit index, from which B04 = US 7,042,860 was read).
6. Which pre-grant claims (79, 80, 86, 89) survived into the granted set — unresolved, so no mapping is offered to them.

6. Bottom line

• Most relevant prior art for US 8,289,939: U.S. Patent No. 7,158,501 B2 to Kasami et al. It is the only reference that has been asserted against this patent in an AIA proceeding (sole ground, IPR2022-00958), it is available as §102(e) art on its 29 May 2002 U.S. filing date irrespective of how the priority dispute resolves, and it squarely discloses beam-based multi-module operation with reception-triggered transmission disable plus an express adjacent-channel/interference rationale. It is the best §102 candidate for claim 30 and for claims 7, 8, 9, 10, 13 and 14, and a contested §102 candidate for claims 1 and 15. Caveat, stated once more: the Board declined to institute on it.
• Second tier: US 7,042,860 (Kasami/Obayashi) and US 5,515,378 (Roy III) — the first for the "restraining transmission" element (subject to its unverified filing date), the second for claim 9 and the "plurality of access points" preamble. Neither anticipates an independent claim on the record as it stands.
• The 802.11 standard materials (802.11-1999, 802.11h, Gast, O'Hara & Petrick) are §102(b) prior art but do not disclose cross-access-point coordination; they belong to a §103 case aimed at claim 3 and claim 11.
• No single reference of record anticipates claims 1, 15 and 30 together. Every candidate fails on at least one of: (i) the reactive, while-receiving ascertaining step; (ii) "at least two other access points" (claim 1); (iii) the "ongoing" second signal + third channel combination (claim 15); or (iv) the cross-channel restraint (claims 1/30). That is why the record shows §103 obviousness, not §102 anticipation. Any prior-art statement that represents these references as anticipatory should be treated as unverified.
• §112 ¶ 6 remains the parallel track. Because "signal transmission/reception coordination logic" was treated as a means-plus-function term in C.D. Cal. and E.D. Tex. (with corresponding structure identified as logic 404 / MAC coordinator logic 606 and equivalents), any §102 case must map to disclosed structure — which raises the bar for generic "controller" mappings of the kind used for Kasami's sections 18/19.

7. Sources

Not retrieved / not asserted: the front-page (56) reference list of US 8,289,939; the filing dates of US 7,042,860 and US 7,127,211; the identity and content of US 7,127,211; the IPR institution decision; the B01–B26 claim charts; serial numbers for the contentions' remaining art-group labels.

I'll ground the combination theories in the actual references where possible, rather than assuming their disclosures.

Obviousness Analysis — U.S. 8,289,939 B2 under 35 U.S.C. § 103

Building on prior sections. This section assumes the claim text, element breakdown, ownership/priority history, litigation posture, and face‑of‑patent citation list already established above. It does not repeat them; it maps those references onto the claims and states motivations. Where the earlier "Prior Art" section flagged that reference disclosures were unverified, that limitation is carried forward and, where I closed a gap this session, marked [NEWLY VERIFIED].

0. Two thresholds before any combination is assessed

(a) Legal framework. The application was filed 2003‑11‑03 (pre‑AIA), so pre‑AIA § 103(a) governs, applied through the Graham factors and the KSR rationales / MPEP 2143. The patent carries a § 282 presumption of validity. Critically for a § 103 theory: the applicant's own Background (§[0004]–[0006]) concedes omni‑directional WLAN drawbacks including "electromagnetic interference is unmanaged" and that "inefficiencies may multiply unchecked if two or more centralized points of emanation happen to be positioned so as to have overlapping coverage areas" — an admission that the problem set was known, which weakens any "unexpected problem solved" narrative.

(b) Claim construction changes what the prior art must show. Under the E.D. Tex. construction, "signal transmission/reception coordination logic" is means‑plus‑function, with corresponding structure = the FIG. 7/12 (and per Vivato, FIG. 13) algorithms. Under W.D. Tex. (Albright, 9/30/2022) it is not § 112 ¶ 6. This is not academic: under In re Donaldson, a § 112 ¶ 6 claim is still invalid under § 103, but the prior art must disclose the recited function and the disclosed structure or an equivalent — a narrower target than a plain‑meaning "any logic that does this." A § 103 case built on Kasami must therefore be briefed on the "FIG. 7 aggregation structure" axis, not just the functional axis. That is the single largest evidentiary risk in what follows.

(c) Priority dispute does not move the best art. Cisco disputed provisional priority (FN1 of the IPR2022‑00958 petition). That fight matters for § 102(b) carve‑outs on mid‑2002 references — but Kasami is § 102(e) art as of its U.S. filing date of 2002‑05‑29 regardless, because pre‑AIA § 102(e) does not travel back to a foreign (§ 119) priority date (In re Hilmer). Kasami therefore qualifies whether the '939 dates to 2002‑11‑04 or 2003‑11‑03. The strongest combination should be built so that the priority issue is irrelevant.

1. The element "gaps" any § 103 combination must fill

2. Reference set: what is verified as to disclosure vs. cited-only

Cisco's non‑patent exhibits (Gast 802.11 Wireless Networks (Apr 2002) = 1006; O'Hara & Petrick IEEE 802.11 Handbook: A Designer's Companion (1999) = 1012; Lehne (1999) = 1009; Litva (1996) = 1008; Bhode & Perini (2001) = 1007; Held (2001) = 1010; Roy US 5,515,378 = 1011) were retrieved as an exhibit list. Their disclosures were not verified this session; the 802.11 handbooks are the obvious source for the CCA/busy‑indication and CSMA/CA mechanisms the spec refers to.

3. Combination scenarios and the motivation for each

Combination 1 — Kasami alone (the Cisco theory; claims 15–22, 30–35)

Mapping. Kasami's one apparatus = the "wireless I/O unit"; receiver/transmitter module pairs 11‑1/12‑1, 11‑2/12‑2, 11‑3/12‑3 = first/second/third "access points"; the reception‑end detecting section = the coordination logic's "ascertaining"; Kasami claim 4 = the restraint; Kasami's FIG. 10 (multiple simultaneous receptions) + "required time" field in the packet (9:42‑51) = the "ongoing" reception; the multi‑beam array's distinct beams = distinct "spatial channels."

Motivation (KSR/MPEP 2143).

• (C) Known technique improving similar devices in the same way — Kasami is the same device class (one station, multiple simultaneous TX/RX paths, one array) and its stated object is "good communication… without causing interference between transmission and reception" (7:46‑49).
• (D/F) Known problem, recognized in the art — Kasami expressly identifies "where a channel to be used has been an adjacent channel," "the signals of the respective channels interfere with each other, and a data transmission error occurs" (2:49‑54). That is G5/G6 in the prior art's own words.
• Reasonably pertinent art / same field of endeavor — Kasami's background expressly invokes SDMA applied to an 802.11 CSMA/CA WLAN, i.e., the identical architecture to the '939's FIG. 2/6.

Weak point. Kasami's "channel" difference is partly a spatial‑channel argument (Cisco's own petition relies on it, pages 41–54, PageIDs 1986–1999). If the district court reads "channel" as a frequency channel, the claim‑30 mapping degrades and must be carried by the "adjacent channel" passage plus an 802.11 reference (Combination 2).

Combination 2 — Kasami + 802.11/CSMA‑CA references (Gast 1006; O'Hara & Petrick 1012; the 802.11 standard)

What it adds. The 802.11 PHY's CCA/busy indication, the MAC's deferral behavior, and the understanding that a station's "medium busy" state is a per‑channel physical‑layer output. That converts Kasami's time‑based "reception end time" restraint into the '939's "receive indicator → constructive receive indicator → MAC do‑not‑transmit input" architecture (G7), and supplies the per‑channel dimension (G5/G6).

Motivation.

• (A) Combination of known elements according to known methods → predictable result. Gating a transmitter on a CCA‑busy signal is a known, single‑bit, well‑understood operation; the '939's own specification says the constructive receive indicator "may comprise an indication for one or more predetermined inputs, such as a CCA or busy/non‑busy input" of the MACs. The patent owner cannot argue unpredictability about an implementation its own spec calls conventional.
• (C) Kasami's background frames its problem as arising in an 802.11 CSMA/CA WLAN; a POSITA working on Kasami would consult the 802.11 medium‑access rules by necessity.
• Finite number of predictable solutions (MPEP 2143.02/2144.04) — the implementer's choices (derive the receive indicator from CCA vs. a dedicated line; combine with a logical OR vs. a wired‑OR; group globally vs. per channel; gate at MAC vs. baseband) are a small, closed set with predictable outcomes. The '939 claims each of these as alternatives.

Combination 3 — Kasami + Nevo (US 2003/0214961, plus family members US 6,990,082 / US 7,239,615 on the face)

What it adds — and it is the strongest secondary. Nevo discloses a device with two co‑located transceivers and controller managers, plus a network manager that coordinates transmit and receive operations so the device can operate both radios contemporaneously; the coordination includes "temporarily suspend signal transmission" by one radio and muting a radio while the other operates. That is functionally the '939's MAC coordinator logic + constructive receive indicator + restraint structure (G7), and it supplies the architectural teaching that a supervisor arbitrates between physically co‑located radios.

Motivation.

• (C) Use of a known technique to improve similar devices in the same way. Both Kasami and Nevo address the same physical problem — co‑located transceivers whose simultaneous TX/RX interferes — and Nevo's own abstract frames the goal as enabling contemporaneous communication while proactively avoiding interference.
• (F) Design incentives. A POSITA integrating multiple radios on one chassis/platform has an obvious incentive to add an arbitration layer; the '939's FIG. 6 (MACs 604 + MAC coordinator logic 606 + plural BB units 608) is exactly that structure.
• Reasonable expectation of success. Nevo's coordinator already treats TX/RX state as a shared, arbitrable resource; adding a receive‑state input and a mute output requires no change in Nevo's principle of operation.

Note on the "different networks" objection. A patent owner will argue Nevo is about dissimilar protocols/networks (Bluetooth/802.11) rather than one WLAN, and therefore not analogous. That is a weak argument: the § 103 test is whether the reference is reasonably pertinent to the particular problem — co‑located‑radio self‑interference — which it plainly is, and Nevo's own specification describes operating both transceivers in receive simultaneously and alternating transmits, i.e., the exact arbitrated TX/RX schedule the '939 claims.

Combination 4 — Kasami + Gans (US 5,987,037) and/or Kasami + Frank (US 2004/0063468)

What it adds. Independent, robust support for G1: a multiple‑beam wireless system (Gans, § 102(b), 1999) and a base station subsystem that schedules a different user in each of multiple fixed beams and transmits concurrently per beam (Frank).

Motivation.

• Both are in the same field of endeavor (cellular/WLAN access infrastructure using antenna arrays) and address the same problem (capacity/spectral reuse via multiple concurrent beams).
• (A)/(F) Once a POSITA multiplies concurrent beams to raise sector capacity — the express object of both — the self‑interference problem necessarily arises, and Kasami supplies the recognized remedy. This is the classic "reason to combine: the secondary reference creates the condition the primary reference was designed to cure."
• Rhetorical/legal value: combining with Gans (1999 issue; § 102(b)) removes the priority fight and the "beams aren't access points" fight from the critical path, because the multibeam‑=‑multiple‑coverage‑areas teaching no longer depends on construing Kasami.

Combination 5 — Kasami + McFarland (US 6,807,146 / Atheros family)

What it adds. G6/G8: the recognition that adjacent sub‑channels/frequency channels bleed into one another unless separated, and that nodes can simply avoid using sub‑channels occupied by others — the exact logic behind the '939's per‑channel grouping (channel assignment information 802), its cross‑channel restraint, and its masking register 814.

Motivation.

• (C)/(D) Applying "keep adjacent channels from interfering" to a per‑channel transmission‑gate is a known technique used to improve a similar device in the same way; the '939's cross‑channel restraint is the direct, predictable consequence.
• (B) Substitution of one known element for another — substituting a per‑channel gate for Kasami's global gate yields predictable results (better throughput without the cross‑channel failure mode).

Combination 6 — Kasami + Adachi (US 2003/0064752 / US 6,983,167) (flagged inference)

Why this would be unusually strong if confirmed. If these are the Toshiba SDMA applications of the same inventive group — and "Adachi, Tomoko" appears as a named co‑inventor on the Kasami application — then the combination is same‑assignee, same‑inventors, same‑technology, and would be very hard to attack as hindsight‑driven or non‑analogous. Verification required of the Adachi references' disclosure and inventorship overlap before this is asserted as anything more than a lead.

Combination 7 — Hildebrand (US 7,127,211) for claims 16/17

Claim 16's "inter‑modulation distortion" is a mechanism claim. Hildebrand (retrieved this session only as an exhibit‑list entry — "U.S. Patent No. 7,127,211 to Hildebrand, et al.") is identified in the petition as addressing inter‑modulation in multi‑transmitter base stations with shared transmit/receive antennas. Combined with Kasami's express statement that simultaneous TX/RX "may act as an interference and affect on the reception… thus disabling reception" (2:10‑15), a POSITA would understand the restraint to prevent IM products. Motivation: (C), and the claim recites a result (what the restraint prevents), not a structure — a § 103 point that also implicates whether the limitation carries patentable weight at all (the petition raises this in the alternative).

4. Claim‑by‑claim § 103 posture

Method / system claims (the "monitoring… detecting… providing at least one instruction to at least two medium access controllers" subject matter recited in the abstract; not reached in IPR2022‑00958): Kasami + Nevo is the combination to brief. Kasami supplies multiple receiver modules and a control section that gates multiple transmitter modules (claim 14's synchronous/common‑back‑off across modules is the ancestor of "provide the same instruction to at least two MACs"); Nevo supplies the controller‑manager‑over‑plural‑transceiver architecture and the suspend‑transmission instruction.

5. Where the § 103 case is weakest (argue this before the examiner does)

1. § 112 ¶ 6 structure. Under the E.D. Tex. construction, the functional showing is not enough — the prior art (or the combination) must disclose the FIG. 7/12 aggregation structure or an equivalent. In re Donaldson permits the § 103 challenge, but the burden shifts to a structure comparison. This, not the Kasami merits, is why the prior IPR is the wrong vehicle to re‑run unmodified.
2. "Channel." If construed as frequency channel, claim 30's "different from" and claim 1's cross‑channel clause need substantive support; use McFarland's adjacent‑channel teaching and 802.11's channel plan, and do not rest on a "spatial channel" theory.
3. § 325(d) / "already considered." Face‑of‑patent references (Nevo/Zehavi/Chen/Adachi/McFarland family members) were before the examiner. Kasami was not — which is why Kasami‑anchored grounds are the cleaner § 325(d) posture even though Kasami itself was the subject of the earlier (denied) petition.
4. Secondary considerations. I found no evidence of commercial success, licensing‑driven design‑around, or copied‑by‑competitors nexus. The one market fact in the record is the commercial failure of the Vivato product and the 2009 foreclosure — which undercuts (though does not refute) a commercial‑success argument.
5. Institution denial is not a § 103 holding. A denial of institution creates no estoppel (§ 315(e)(2) attaches only after an FWD) and no issue preclusion. It does, however, mean the Board was, at minimum, unpersuaded on the record presented — so any re‑filed ground must be materially different and materially better evidenced (e.g., adding Gans/Frank for G1, adding Nevo for G7, and pre‑emptively curing the § 314(a)/Fintiv factors now that the E.D. Tex. lead case was dismissed with prejudice in January 2026).

6. Bottom line

• The independent claims are, on the present record, more likely than not obvious over Kasami alone as to the functional elements (ascertain reception → restrain other transmit paths → prevent degradation → cross‑channel/adjacent‑channel rationale), and clearly obvious over Kasami in view of one or more of Gans, Frank, Nevo, and McFarland as to the contested structural elements (plural co‑located beam‑served "access points"; a coordinating manager over plural radios; per‑channel grouping).
• The claims that are genuinely harder are those keyed to the FIG. 6 MAC‑coordinator architecture (claims 10–12 and the system/method subject matter) and to the cross‑channel "different channel" limitation (claim 30 / claim 1 third clause) — and those difficulty points are construction‑driven, not disclosure‑driven.
• Recommended combination hierarchy for a filing or an invalidity contention: (1) Kasami + Gans + Nevo as the lead (priority‑dispute‑proof; forecloses the beams‑aren't‑access‑points and no‑coordinator fights); (2) Kasami + 802.11 handbooks for the CCA/constructive‑indicator mechanism; (3) Kasami + McFarland for per‑channel grouping and adjacent‑channel restraint; (4) add Hildebrand for claims 16/17 and Adachi for the SDMA specifics only after verification.
• Do not assert these as established outcomes. The Kasami disclosure is verified; Gans, Frank, McFarland (full text), Hildebrand, the Adachi references, and the non‑patent exhibits are cited‑only or title‑level in my retrieval and must be read and charted element‑by‑element before any of the above is relied on. The E.D. Tex. § 112 ¶ 6 order and the "Defendants' IPR on the '939" lead remain the two open items identified earlier that most affect how this § 103 theory should be packaged.