US 7020501

I'll verify the patent record against live sources before summarizing.

US 7,020,501 B1 — Verification Summary

Scope note: All identifiers below are reported literally as they appear in the record. I found no Federal Circuit (CAFC) 2026 docket involving patent 7,020,501; see "Litigation" below. Search results containing adjacent numbers (e.g., 7,020,701; 7,421,257; 7,979,096) are excluded per your instruction — those are different patents in the same family or unrelated, not the patent you asked about.

Bibliographic record

Abstract (verbatim): "A system for conserving energy in a multi-node network (110) includes nodes (205) configured to organize themselves into tiers (305, 310, 315). The nodes (205) are further configured to produce a transmit/receive schedule at a first tier (310) in the network (110) and control the powering-on and powering-off of transmitters and receivers in nodes (205) in a tier adjacent (315) to the first tier (310) according to the transmit/receive schedule."

Source: https://patents.google.com/patent/US7020501/en

Plain-language overview of each independent claim

Claim 1 — Method of conserving energy in a wireless-network node. The node receives a first "powering-on schedule" from another node; selectively powers on its transmitter and/or receiver per that schedule; derives a second powering-on schedule from the first; and transmits that second schedule to other nodes while its transmitter is on. The key structural feature is that every node re-broadcasts a schedule one hop further out, so the schedule propagates down the hierarchy.

Claim 4 — Apparatus (node) version of claim 1. Transmitter + receiver + processing unit that performs the same receive-schedule / power-on-per-schedule / derive-second-schedule / transmit-second-schedule sequence.

Claim 5 — Computer-readable medium version of claim 1. Same steps expressed as stored instructions. Textual note: the claim recites "a powering-on schedule" but later refers to "the first powering-on schedule," so the antecedent basis is imperfect on the face of the printed claim.

Claim 6 — Method of conveying messages in a sensor network. Organize the network into a hierarchy of tiers; transmit transmit/receive scheduling messages throughout; transmit and receive data messages between nodes in adjacent tiers per those scheduling messages; and at least one sensor node in a tier receives data messages from sensor nodes in a higher tier and forwards them to a sensor node in a lower tier. This is essentially "tiered tree forwarding gated by sleep/wake schedules."

Claim 10 — Method of conserving power at an intermediate first node. The first node sits on a path between one or more other nodes and a second node. It powers on its receiver to listen for a scheduling message; receives that message from the second node, where the message specifies (i) a first communication schedule for first-node↔second-node communications and (ii) a second communication schedule for when the first node may communicate with each of the other nodes; then selectively powers its receiver and transmitter on and off per both schedules. The notable limitation: a single scheduling message carries both the upstream link timing and the downstream/child timing.

Claim 14 — Apparatus version of claim 10. First node with transmitter, receiver, and processing unit configured to power on the receiver to listen for the scheduling message, and thereafter power the receiver and transmitter on/off per the two schedules.

Claim 15 — Computer-readable medium version of claim 10.

Claim 16 — Data structure encoded on a computer-readable medium. First data: identifiers of sensor nodes affiliated with a parent node. Second data: a first time schedule for transmitting messages from the parent to the affiliated sensor nodes, plus a second time schedule for receiving messages at the parent from each affiliated sensor node. This claims the affiliation/schedule table itself (in the spec, "affiliated children IDs" + "Tx/Rx schedule" with Parent Tx and Child-to-Parent Tx fields).

Claim 19 — Method (parent-side schedule construction). Receive messages at a first node from neighboring nodes notifying the first node of their presence; determine a first communication schedule for communicating with each neighboring node; determine a second communication schedule for each neighboring node to communicate with other nodes in the network; and transmit a message to each neighboring node including both schedules.

Observations and uncertainties

• Claims are narrower than the "Summary of Invention" bullets. The specification's summary describes a method of merely receiving a powering-on schedule and selectively powering on (¶ [0008]), but the issued independent claims 1, 4, and 5 add the derive-and-retransmit limitations ("producing a second powering-on schedule … and transmitting the second powering-on schedule"). Anyone characterizing the patent's scope from the summary alone would overstate it.
• Tier-direction terminology in claims 10/12/13 is worth flagging: claim 13 (depending from claim 11) recites transmitting scheduling messages to "the second node in a higher tier," while in the specification's FIG. 3 the sink-ward parent (which sources the schedule) is in the lower tier and children are in higher tiers. Claims 12 and 13 appear to use the opposite tier convention from the illustrated embodiment. I state this as a reading of the claim text, not as a verified claim-construction ruling.
• Cited prior art (application-level): US 5,583,866; US 6,192,230; US 6,208,247; US 6,292,508; US 6,381,467; US 6,414,955; US 6,564,074; US 6,694,149. Non-patent items include Clare et al., "Self-Organizing Distributed Sensor Networks"; Doherty, "Algorithms for Position and Data Recovery in Wireless Sensor Networks"; Liu et al., simulation modeling of large-scale ad-hoc sensor networks; and Van Dyck (NIST).
• Family: The patent is the CIP-parent of US 10/328,566 (US 7,421,257, "Receiver scheduling in ad hoc wireless networks"), with continuations US 7,623,897, US 7,979,096, US 7,979,098, US 2015/0029914A1, US 9,674,858, US 10,588,139, US 10,863,528, and (per the cited-by table) US 11,445,523. Note claim 19 of the application publication US 2015/0029914 differs materially (beacon/routing-table subject matter), so claim numbering should not be carried across family members without checking each document.

Litigation / enforcement

• E.D. Tex. case: Azure Networks LLC et al. v. Texas Instruments Incorporated et al., No. 6:10-cv-00681 (E.D. Tex., filed Dec. 22, 2010). Named alleged infringers in the record include Freescale Semiconductor, NXP Semiconductors N.V./B.V./USA, Atmel, Microchip Technology, ZMD America, and Zentrum Mikroelektronik Dresden GmbH. Sources: https://npe.law.stanford.edu/patent/7020501 and the Google Patents litigation link (https://portal.unifiedpatents.com/litigation/Texas%20Eastern%20District%20Court/case/6%3A10-cv-00681). The Stanford NPE database page reported "Displaying 1 – 2 of 2" cases while surfacing only the 2010 case in the retrieved snippet, so a second case may exist that I could not display.
• Assignments: BBNT Solutions LLC (original) → BBN Technologies Corp. (merger, 2006) → Stragent LLC (2009) → Power Mesh Networks LLC / Azure Networks LLC → Tri-County Excelsior Foundation / OSO IP LLC → III Holdings 1, LLC (2014-06-24).
• CAFC 2026: My searches found no 2026 Federal Circuit docket, appeal, or opinion involving US 7,020,501. The 2026 CAFC results returned (e.g., ParkerVision v. Qualcomm, Netlist v. Micron, Magnolia v. Kurin) involve unrelated patents and must not be conflated with this patent. I flag this as a negative search result, not proof of absence — I did not have direct query access to the CAFC docket system or USPTO PatentCenter, so an appeal or administrative proceeding outside indexed sources cannot be ruled out.

Confidence: High for the bibliographic data, abstract, and claim text (taken from the full patent text and corroborated by RPX/Justia). Medium for current assignee of record (Google Patents disclaims verification). Low/uncertain for any litigation after 2010 and for the existence of any second, non-displayed case.

I'll research litigation involving US Patent 7,020,501. Let me start with the litigation-specific sources.

Let me gather more details on the identified case and confirm whether there are additional cases.

Let me confirm the outcome and check for any additional cases involving this specific patent.

Litigation Involving U.S. Patent No. 7,020,501

I ran targeted searches against patent-litigation sources (Stanford NPE Litigation Database, Justia Dockets, Unified Patents, Techdirt, and the Google Patents litigation family flag). Here is what is confirmed, plus one item I could only partially verify.

Confirmed Litigation

Case: Azure Networks LLC et al. v. Texas Instruments Incorporated et al.
(also cited as Azure Networks LLC and Tri-County Excelsior Foundation v. Texas Instruments Inc., et al.)

Grounding / sources:

• The complaint confirms TCEF is "the owner by assignment" of the '501 Patent and Azure is the "exclusive licensee," and identifies accused products such as the TI CC2430 SoC and various RF transceivers (Azure Networks v. Texas Instruments complaint, Exhibit A) — see the court filing mirror: https://iknow.stpi.narl.org.tw/Post/Files/Complaint/Complaint_pclass_11_A003_Azure%20Networks%20%20v.%20Texas.pdf
• Case record: Stanford NPE Litigation Database, https://npe.law.stanford.edu/patent/7020501 (the '501 patent appears in connection with this action) and Justia Dockets, https://dockets.justia.com/docket/texas/txedce/6:2010cv00681/127299
• The Google Patents record for US 7,020,501 carries a "Family has litigation" flag pointing to Eastern District of Texas case 6:10-cv-00681 (https://portal.unifiedpatents.com/litigation/Texas%20Eastern%20District%20Court/case/6%3A10-cv-00681).

Context on the Asserting Parties

• The '501 patent was originally assigned to BBNT Solutions LLC, later BBN Technologies Corp., and ultimately passed through Stragent, LLC → Power Mesh Networks, LLC → Azure Networks, LLC → Tri-County Excelsior Foundation (with Azure holding an exclusive license back). This chain is documented in the USPTO assignment records reflected on the Google Patents page and in contemporaneous reporting.
• The Dec. 22, 2010 suit was filed the same week as a companion Azure/TCEF suit, Azure Networks LLC et al. v. Alereon, Inc. et al., which asserted different patents (e.g., U.S. 7,218,633 and related personal-area-network patents) — not the '501 patent. I am flagging this so the two 2010 filings are not confused.

Unverified / Could Not Confirm

1. Second case in the NPE database. The Stanford NPE page states "Displaying 1–2 of 2" cases involving the '501 patent, but only the Texas Instruments action (6:10-cv-00681) rendered in the retrieved snippet. A separate, later Azure Networks LLC v. Texas Instruments Inc., No. 6:15-cv-00032 (E.D. Tex., filed Jan. 12, 2015, Judge Robert W. Schroeder III) exists and shows as "Disposed" with an order dismissing all claims and counterclaims with prejudice (Justia/UniCourt). However, I could not confirm from the sources retrieved that the '501 patent was among the patents asserted in that 2015 case, so I am not counting it as a confirmed '501 action.
2. Final disposition of 6:10-cv-00681. The docket reflects termination, but I did not retrieve the specific dispositive order (dismissal, settlement, or judgment). I will not guess at the outcome.
3. No PTAB activity specific to the '501 patent was identified in the searches performed.

Bottom Line

Based on the sources searched, the only confirmed litigation specifically asserting U.S. Patent No. 7,020,501 is:

Azure Networks LLC v. Texas Instruments Incorporated et al., No. 6:10-cv-00681 (E.D. Tex.), filed Dec. 22, 2010, asserting the '501 patent against TI, Freescale, Atmel, NXP B.V., NXP Semiconductors USA, Microchip, ZMD America, and Zentrum Mikroelektronik Dresden.

A second, potentially related Azure Networks action (6:15-cv-00032) was dismissed with prejudice, but I could not verify that the '501 patent was asserted in it. If you need the precise final judgment/termination orders and the exact list of patents in the 2015 case, I would recommend pulling the PACER dockets for 6:10-cv-00681 and 6:15-cv-00032 directly, since the free web sources resolved only the pleading and docket-summary level.

PTAB / AIA Trial Landscape — U.S. Patent No. 7,020,501

"Energy efficient forwarding in ad-hoc wireless networks" · Appl. No. 09/998,946 · Filed 2001-11-30 · Granted 2006-03-28 · Inventors Elliott & Pearson · Original assignee BBNT Solutions LLC
Current assignees of record (per Google Patents): OSO IP LLC; III Holdings 1, LLC · Legal status: Expired – Lifetime (adjusted expiration 2023-08-09)

Proceedings overview

Total AIA trial proceedings on U.S. Patent No. 7,020,501: zero — no IPR, no PGR, and no CBM has ever been instituted, terminated, or even filed against this patent on the record; the USPTO Open Data Portal returns an empty AIA-trial set, and targeted web searching surfaced no proceeding (PTAB, docket aggregator, or party disclosure) naming the '501 patent.

The structured "PTAB proceedings on file" block is the canonical source and reports no PTAB activity, with no active trials, no claims invalidated, no claims sustained, no settlements, and no institution denials — simply an absence of filings. Because there is no proceeding, there is no final written decision, no adverse judgment, no panel to name, and no Federal Circuit appeal to report for the '501 patent. Nothing below is invented to fill that gap; where I could not verify a fact, I say so.

The defensive posture this creates is unusual and should not be misread as "the patent is hardened." Two facts dominate:

1. The patent is expired. The recorded adjusted expiration is 2023-08-09. As of today (2026-09-22) there is no prospective infringement to enjoin and no ongoing royalty to accrue. Any assertion today can only reach past damages, and even then only within the 35 U.S.C. § 286 six-year lookback from the filing of a complaint — practically a narrow 2020–2023 window.
2. No challenger ever tested these claims at the PTAB. Zero IPRs means zero claim cancellations — but it also means the claims are untested, not validated, and no petitioner-side estoppel exists to constrain anyone. The strongest defensive artifact in this file is not a PTAB decision; it is the expiration certificate date.

Proceedings on file

None. There is no IPR20xx-#####, PGR20xx-#####, or CBM20xx-##### number to report for the '501 patent. I did not fabricate one, and I flag explicitly that the following related matters surfaced during research and are not proceedings on the '501 patent:

• IPR2023-00529 / IPR2023-00531 — [Microsoft Corp.](/litigations/by-plaintiff/Microsoft%20Corp.) & Affirmed Networks v. Lemko Corp. — unrelated patents (7,653,414; 7,855,988).
• PTAB petition against U.S. Pat. 8,xxx,832 (dSDN / fxDevice) — unrelated patent and unrelated parties.
• CSR PLC v. Azure Networks, LLC, No. 14-976 (U.S. Apr. 20, 2015) — a Supreme Court GVR (vacate-and-remand in light of Teva v. Sandoz) arising from Azure Networks, LLC v. CSR PLC, No. 6:11-cv-139 (E.D. Tex.) — the '129 patent (personal area network / MAC address claim construction), not the '501 patent. See the Federal Circuit opinion at https://www.finnegan.com/a/web/47287/2G4ozr/azure_v_csr.pdf and the cert. disposition at https://casetext.com/case/plc-v-azure-networks-llc.

Caveat on completeness (stated rather than papered over): I searched for PTAB filings under the patent number, the "Azure Networks" and "III Holdings 1" owner names, and the E.D. Tex. case number. A proceeding could in principle exist that is not indexed by public aggregators (e.g., an early IPR terminated before institution with minimal fanfare). The ODP "no proceedings" result plus the absence of any web hit makes that unlikely, but the authoritative confirmation is a PTAB E2E / PTAB API query under US7020501, which I recommend running before relying on this in a brief.

Context that matters more than a nonexistent FWD: the pre-AIA litigation record

Because there is no PTAB record, the only adversarial testing of the '501 patent happened in district court:

Sources: complaint PDF (https://iknow.stpi.narl.org.tw/Post/Files/Complaint/Complaint_pclass_11_A003_Azure%20Networks%20%20v.%20Texas.pdf); Stanford NPE Litigation Database entry for patent 7020501 (https://npe.law.stanford.edu/patent/7020501); Google Patents litigation link to https://portal.unifiedpatents.com/litigation/Texas%20Eastern%20District%20Court/case/6%3A10-cv-00681.

Note the database quirk: the Stanford NPE page states "Displaying 1 - 2 of 2" cases for '501 but renders only the 2010 case; the second may be the related 6:11-cv-00139 (Azure Networks v. CSR, filed 2011-03-22) or a later 2015 Azure filing window. Treat the case count as unconfirmed.

Strategic summary

Which claims are canceled vs. sustained vs. untested. All 19 claims of the '501 patent are UNTESTED at the PTAB — nothing is canceled, nothing is adjudicated valid. Claims 1, 4, and 5 are the "powering-on schedule / derive-a-second-schedule" family (independent claim 1; claim 4 apparatus; claim 5 CRM); claims 6–9 cover tiered sensor-network message conveyance; claims 10–15 cover an intermediate-node scheduling-message method/apparatus/CRM with first and second communication schedules; claims 16–18 cover the affiliation/schedule data structure; claim 19 covers the parent-node schedule-distribution method. The absence of any IPR is a real weakness in the patent's paper record relative to heavily-litigated NPE patents (compare the family's own later continuations, which were repeatedly asserted) — but it means a defendant gets no free claim cancellation to wave at opposing counsel.

Estoppel landscape. Because no IPR/PGR was ever filed on the '501 patent, § 315(e)(2) estoppel is empty: no petitioner, real party in interest, or privy is barred from raising any ground, and no defendant inherits a pre-vetted invalidity record. Conversely, nothing constrains your use of § 102/§ 103 art at the PTAB or in court. Practical constraints on a new petition, though, are severe: (a) § 315(b) — a one-year bar runs from service of a complaint alleging infringement of the patent, and any 2010/2011-era service long predates today; (b) § 311(b) limits IPR to patents and printed publications, so the 2001-era non-patent literature cited during prosecution (Clare et al., "Self-Organizing Distributed Sensor Networks," Mar. 7, 2001; Doherty, Berkeley; Liu et al., European Simulation Interoperability Workshop, Jun. 25–27, 2001; Van, "Distributed Sensor Processing over an Ad Hoc," NIST; Liu/Lee, "Bluetooth Scatternet Route Structure," IEEE) is only usable to the extent it qualifies as a printed publication; (c) expiration (2023-08-09) makes an IPR an expensive nullity exercise — you would be paying to invalidate claims that cannot be infringed going forward. PGR is unavailable (pre-AIA filing date of 2001-11-30), and CBM both sunset (2020-09-16) and would face a hard "technological invention" fight on sensor-network power management claims.

Pattern signals. The asserted owner chain is a classic monetization sequence rather than an operating company: BBNT Solutions → BBN Technologies → Stragent, LLC (2009) → Power Mesh Networks, LLC → AZURE NETWORKS, LLC (2009-10-07) → TRI-COUNTY EXCELSIOR FOUNDATION (2010-09-01, a court-appointed-special-advocate charity formed by CASA of Harrison County — used, per the appellees' brief in Azure v. CSR, to bolster E.D. Tex. venue and generate tax deductions) → back to AZURE NETWORKS (2013-08-05 and confirmatory assignments) → III HOLDINGS 1, LLC (Intellectual Ventures) (2014-06-24). No defensive aggregator appears anywhere in the chain for the '501 patent. Unified Patents is not on file here (Unified's Nov. 5, 2014 IPR targeted III Holdings' U.S. 7,702,781 on cloud storage — a different patent, and its own campaign), and no third-party IPR challenge to the '501 patent has ever been filed by anyone. The patent owner has therefore never had to defend these claims at the PTAB and has never lost a claim here.

Recommended next steps

1. Lead with expiration, not with invalidity. Confirm the adjusted expiration date (recorded here as 2023-08-09) against USPTO PatentCenter before responding to any demand. If a letter or complaint threatens prospective infringement or an injunction, the response is that the patent term has run. If it seeks past damages, immediately audit the § 286 six-year window and the patent's expiration to bound the exposure, and demand the demand-letter sender identify a live, unexpired claim — a well-asserted expired patent is a § 285 fee-shifting candidate.
2. Force claim-number specificity. The 2010 complaint pleaded only "one or more claims." Any current assertion should be met with a demand to identify asserted claims with particularity. With no PTAB record, there is no claim-construction or invalidity record to borrow — the asserted claim number is your leverage point.
3. If you nevertheless want a PTAB record, run a § 315(b) and expiration triage first. A petition is time-barred if the patent owner (or a privy) served an infringement complaint on you more than one year ago, and institution of a review of a patent that expired in 2023 is rarely cost-justified. If a fresh complaint was served on you within the last twelve months, a defensive IPR remains formally available; budget for it only after confirming the six-year damages tail makes the invalidity fight commercially worthwhile.
4. Pull the authoritative PTAB record yourself before filing anything, since my negative result rests on the ODP block plus absence of web hits: query PTAB E2E (https://ptacts.uspto.gov/ptabweb) and the USPTO Open Data Portal for 7020501, and confirm the family members' status separately if the demand letter cites continuations — US 7,421,257 (from CIP 10/328,566), US 7,623,897, US 7,979,096, US 7,979,908, US 2015/0029914, US 9,674,858, US 10,588,139, and US 10,863,528. Those continuations have their own expiration dates and their own (unverified here) PTAB histories; do not let an expired '501 claim be bootstrapped into a live claim from a later-issued continuation without checking each patent number independently.
5. Verify the 2010–2015 litigation outcome. I could not confirm the disposition of 6:10-cv-00681 from the sources retrieved. Its resolution (settlement/license vs. judgment) materially affects any damages or license-defense theory, and any license taken in that campaign may run to the current assignee.

Bottom line for a defendant today: there is no PTAB decision to cite, because there is no PTAB proceeding — but you are not without a defense. The patent's expiration on 2023-08-09, combined with the absence of any adjudicated claim construction or validity finding in the entire assertion history of this patent, leaves any current demand letter resting on an unexpired-claim theory that the patent owner must prove and, on the record available, cannot.

I'll research the assignment record, litigation, and the entities in this chain before writing.

Good — rich findings. Let me dig into the intermediate entities and the litigation specifics.

Assignment & Ownership Analysis — US 7,020,501 B1

"Energy efficient forwarding in ad-hoc wireless networks"
App. 09/998,946 · filed 2001‑11‑30 · issued 2006‑03‑28 · inventors Elliott & Pearson · original assignee BBNT Solutions LLC

Data-integrity note (read first). I could not retrieve the USPTO Assignment Center / assignment.uspto.gov records for this patent with the tools available in this session. Accordingly I have no reel/frame numbers and no correspondent-of-record names for any link in this chain, and I will not invent them. The timeline below is reconstructed from the Google Patents "Legal Events / reassignment" record (fetched 2026‑09‑22 from https://patents.google.com/patent/US7020501/en), which reports assignor, assignee, conveyance type and a date but not execution vs. recordation distinction, reel/frame, or correspondent. Cross-references are from dockets, the Stanford NPE Litigation Database, Unified Patents, and law-firm case reporting as cited. Verification via Assignment Center is still required for reel/frame and correspondent fields.

Inventors

Unusual-pattern check: No departure pattern. Neither inventor appears as an assignor in any subsequent recorded transaction — the last record naming them as assignors is the 2002‑02‑27 employer assignment. There is no record evidence that either inventor left within 12 months of filing, and no record evidence of any inventor-held retained rights. So the "inventors bail out before the fire-sale" tell is not present; the portfolio sale was corporate, not inventor-driven. (Note: absence of later inventor names in a recordation database is weak evidence either way — inventors typically don't appear in asset-transfer records.)

Original assignee

BBNT Solutions LLC (issued patent face; recorded assignment 2002‑02‑27).

• Line of business: BBN / Bolt Beranek and Newman is a research-and-development and government/defense contractor — not a sensor-network product vendor. Its output is contract R&D and prototypes, not a commercial product line. I found no evidence that BBNT Solutions or its successor shipped a product embodying claims 1–19; the specification's monitor-point/sensor-node architecture reads as a research program artifact, and the covered subject matter (low-power ad-hoc sensor networking) was not a BBN commercial offering.
• Corporate status: BBNT Solutions LLC merged into BBN Technologies Corp. (recorded 2006‑03‑02, conveyance "Merger"). BBN Technologies was subsequently acquired by Raytheon (now Raytheon BBN Technologies); this is corroborated on the patent's own citation record, where later BBN-originated patents list "Raytheon Bbn Technologies Corp." as assignee. Operating, and now a Raytheon (RTX) subsidiary — not dissolved, not in bankruptcy.
• Notable timing: the ad-hoc sensor-network patent family was recorded out of BBN Technologies on 2009‑08‑19, roughly two months before Raytheon's acquisition of BBN closed. A portfolio divestiture immediately ahead of an acquisition is a classic corporate-housekeeping/fire-sale pattern, though it is not by itself proof of distress.

Assignment timeline

All dates below are as reported in the Google Patents legal-events record. Reel/frame: not retrievable by me — ⚠️ unverified. Correspondent: not retrievable by me — ⚠️ unverified. I have flagged both rather than guess.

1. 2002‑02‑27 (recorded) — Reel ⚠️ n/a — not retrieved

   • Conveyance: Assignment of assignors' interest
   • Assignor: Brig Barnum Elliott; David Spencer Pearson
   • Assignee: BBNT Solutions LLC
   • Correspondent: ⚠️ not retrieved
   • Context: routine inventor-to-employer assignment at original assignee.

2. 2004‑05‑12 (recorded) — Reel ⚠️ n/a — not retrieved

   • Conveyance: Patent & Trademark Security Agreement
   • Assignor: BBNT Solutions LLC
   • Assignee: Fleet National Bank, as Agent
   • Correspondent: ⚠️ not retrieved
   • Context: securitization / secured-lending lien over BBN's patent portfolio (collateral), not a transfer of title.

3. 2006‑03‑02 (recorded) — Reel ⚠️ n/a — not retrieved

   • Conveyance: Merger
   • Assignor: BBNT Solutions LLC
   • Assignee: BBN Technologies Corp.
   • Correspondent: ⚠️ not retrieved
   • Context: internal reorganization — same corporate family, name/successor change only.

4. 2008‑10‑10 (recorded) — Reel ⚠️ n/a — not retrieved

   • Conveyance: Assignment of assignors' interest
   • Assignor: Stragent, LLC
   • Assignee: Power Mesh Networks, LLC
   • Correspondent: ⚠️ not retrieved
   • Context: shell-to-shell transfer inside the Longview, TX assertion cluster. Anomaly: this record predates the 2009‑08‑19 BBN→Stragent record by ~10 months, so it cannot be downstream of the BBN transfer on a single-application reading. Either (a) it covers a different application in the same family, or (b) Google Patents has attached a family-level record to this publication. Treat link 4's position in the chain as unverified.

5. 2009‑08‑18 (recorded) — Reel ⚠️ n/a — not retrieved

   • Conveyance: Release by Secured Party
   • Assignor: Bank of America, N.A. (successor to Fleet National Bank), as Agent
   • Assignee: BBN Technologies Corp.
   • Correspondent: ⚠️ not retrieved
   • Context: lien release — clears the 2004 security interest (Bank of America absorbed Fleet in 2004).

6. 2009‑08‑19 (recorded) — Reel ⚠️ n/a — not retrieved

   • Conveyance: Assignment
   • Assignor: BBN Technologies Corp.
   • Assignee: Stragent, LLC
   • Correspondent: ⚠️ not retrieved
   • Context: transfer-to-asserter — operating R&D contractor sells the sensor-network family to a Longview, TX patent-licensing LLC. This is the pivot out of the operating world.

7. 2009‑10‑07 (recorded) — Reel ⚠️ n/a — not retrieved

   • Conveyance: Assignment
   • Assignor: Power Mesh Networks, LLC
   • Assignee: Azure Networks, LLC
   • Correspondent: ⚠️ not retrieved
   • Context: shell-to-shell transfer, ~7 weeks after the Stragent record.

8. 2009‑10‑27 (recorded) — Reel ⚠️ n/a — not retrieved

   • Conveyance: Release of Security Interest
   • Assignor: Bank of America, N.A.
   • Assignee: BBN Technologies Corp.
   • Correspondent: ⚠️ not retrieved
   • Context: cleanup release of the 2004 collateral record.

9. 2010‑09‑01 (recorded) — Reel ⚠️ n/a — not retrieved

   • Conveyance: Assignment
   • Assignor: Azure Networks, LLC
   • Assignee: Tri-County Excelsior Foundation (Marshall, TX 501(c)(3) / Type‑1 supporting organization to CASA of Harrison County)
   • Correspondent: ⚠️ not retrieved
   • Context: transfer-to-venue anchor — reported as a "donation" of the asserted patents to a local charity; the charity then granted Azure back an exclusive, fully enforceable license. Within ~3.7 months of the first suit.

10. 2013‑08‑05 (recorded) — Reel ⚠️ n/a — not retrieved

    • Conveyance: Assignment
    • Assignor: Tri-County Excelsior Foundation
    • Assignee: Azure Networks, LLC
    • Correspondent: ⚠️ not retrieved
    • Context: chain-of-title correction after the Federal Circuit standing challenge.

11. 2013‑08‑14 (recorded) — Reel ⚠️ n/a — not retrieved

    • Conveyance: Confirmatory Assignment
    • Assignor: OSO IP, LLC
    • Assignee: Azure Networks, LLC
    • Correspondent: ⚠️ not retrieved
    • Context: reorg/cleanup — confirmatory record attempting to paper the whole portfolio chain.

12. 2013‑08‑14 (recorded) — Reel ⚠️ n/a — not retrieved

    • Conveyance: Change of Name
    • Assignor: Power Mesh Networks, LLC
    • Assignee: Balther Technologies, LLC
    • Correspondent: ⚠️ not retrieved
    • Context: name change only — no change in beneficial ownership.

13. 2013‑08‑14 (recorded) — Reel ⚠️ n/a — not retrieved

    • Conveyance: Change of Name
    • Assignor: Balther Technologies, LLC
    • Assignee: OSO IP, LLC
    • Correspondent: ⚠️ not retrieved
    • Context: name change only — Power Mesh → Balther → OSO IP is one entity renamed twice.

14. 2013‑08‑14 (recorded) — Reel ⚠️ n/a — not retrieved

    • Conveyance: Confirmatory Assignment
    • Assignor: Stragent, LLC
    • Assignee: OSO IP, LLC
    • Correspondent: ⚠️ not retrieved
    • Context: chain-of-title repair, same-day batch with 11–13 (four records on a single day).

15. 2014‑06‑24 (recorded) — Reel ⚠️ n/a — not retrieved

    • Conveyance: Assignment of assignors' interest
    • Assignor: Azure Networks, LLC
    • Assignee: III Holdings 1, LLC
    • Correspondent: ⚠️ not retrieved
    • Context: transfer-to-asserter / aggregation exit — III Holdings 1, LLC is a subsidiary of Intellectual Ventures Management, LLC (see §NPE signals 2). This is the terminal recorded event.

Current ownership per Google Patents: "OSO IP LLC; III Holdings 1 LLC." Reading the record together, OSO IP retained the renamed-shell role while the asserted assets moved to III Holdings 1 in 2014.

⚠️ Caveat on records 11–14: these 2013‑08‑14 dated confirmatory/name-change records appear on the family (siblings include US 7,421,257; 7,623,897; 7,979,096; 7,979,098; later 10,588,139 / 10,863,528). I could not confirm from the retrieved data whether each record names US 7,020,501 specifically or a sibling application. Verification against the reel/frame image is required.

Timeline diagram

timeline
    title Ownership of US 7020501
    2002 : Inventors assign to BBNT Solutions LLC
    2004 : Portfolio security lien to Fleet National Bank
    2006 : BBNT Solutions merges into BBN Technologies Corp
    2008 : Power Mesh Networks takes rights from Stragent
    2009 : Stragent acquires family from BBN Technologies
         : Fleet lien released by Bank of America
         : Azure Networks acquires from Power Mesh Networks
    2010 : Donated to Tri-County Excelsior Foundation
         : First suit filed in EDTX against TI and others
    2013 : Confirmatory transfers among Stragent OSO IP and Azure
    2014 : Assigned to III Holdings 1 LLC

NPE / troll-pattern signals

1. Shell-entity transfer — PRESENT

The asset leaves an operating R&D contractor and enters a chain of Texas single-purpose LLCs: BBN Technologies Corp. → Stragent, LLC (2009‑08‑19) → Power Mesh Networks, LLC (2008‑10‑10) → Azure Networks, LLC (2009‑10‑07) → Tri-County Excelsior Foundation (2010‑09‑01) → back to Azure (2013‑08‑05) → III Holdings 1, LLC (2014‑06‑24). Concrete, non-naming-based evidence: (a) Stragent, LLC self-describes as an entity that "develops, acquires, and licenses patent technology" and was named in IPRs (IPR2017‑01502, ‑01519, etc.) as patent owner and in Delaware/EDTX assertion campaigns against BMW, Daimler, Volvo and others; (b) Azure Networks, LLC is listed in the Stanford NPE Litigation Database under the "Acquired patents" asserter category (https://npe.law.stanford.edu/party/azure-networks-llc); (c) Azure is a "Texas limited liability company having its principal place of business in Longview, Texas" per its own complaint, i.e., no manufacturing footprint. Name-suffix evidence alone was not relied on.

2. Known asserter in the chain — PRESENT

• III Holdings 1, LLC — publicly identified by Unified Patents as an Intellectual Ventures subsidiary/NPE ("Intellectual Ventures is a well known NPE which has a subsidiary called III Holdings 1, LLC" — https://www.unifiedpatents.com/insights/2016/5/4/unified-challenges-intellectual-ventures-ivinvents-owned-patent). This falls squarely inside the listed "Intellectual Ventures" NPE category. Onscope lists III Holdings 1's parent as Intellectual Ventures Management, LLC.
• Azure Networks, LLC / Tri-County Excelsior Foundation — plaintiffs in Azure Networks LLC et al v. Texas Instruments Inc. et al, No. 6:10‑cv‑00681 (E.D. Tex., filed 2010‑12‑22), plus ~38 further defendants in Q1 2015 alone per an NPE quarterly report; both are indexed in the Stanford NPE Litigation Database.
• Stragent, LLC — documented serial NPE (39 suits over 51 patents per IPRdaily's NPE survey; PTAB patent owner in the 8,209,705 / 8,566,843 AUTOSAR litigations).
• The named Google Patents litigation link for this patent, E.D. Tex. 6:10‑cv‑00681, is exactly the Azure/Tri-County case.

3. Repeat correspondent across the chain — UNCLEAR (data gap, not a negative finding)

I could not retrieve any correspondent-of-record. I explicitly decline to name a correspondent I cannot verify. Two adjacent, verified observations that bear on the "same lawyer runs the shells" hypothesis but are not correspondent-of-record findings because they come from litigation, not recording:

• Eric M. Albritton, Albritton Law Firm, Longview, TX appeared repeatedly as counsel for the Azure/Tri-County plaintiffs across the 2010–2012 EDTX campaign (e.g., 6:12‑cv‑00252 Azure/TCEF v. MediaTek).
• Azure's principal place of business (Longview, TX) is the same city as Stragent LLC's base of operations — an address/venue cluster worth checking against the reel/frame correspondent fields.
  Recommended verification step: pull the reel/frame images for the 2009‑08‑19, 2009‑10‑07, 2010‑09‑01, and 2013‑08‑14 records and compare the correspondent block. That comparison is the single highest-value follow-up on this chain.

4. Cascading transfers — PRESENT

Five recorded ownership-moving events in a 12‑month window (2009‑08‑19 → 2009‑10‑07 → 2010‑09‑01, plus the two 2009 releases), then four records all on 2013‑08‑14 (two confirmatory assignments and two change-of-name records) involving Stragent, Power Mesh/Balther, OSO IP and Azure — the same interlocking set of principals recurring. The 2013‑08‑14 batch is on its face a chain-of-title repair exercise, which is itself evidence that the prior transfers were being contested (see the standing litigation below).

5. Pre-litigation transfer — PRESENT

Asset recorded to Tri-County Excelsior Foundation on 2010‑09‑01; first suit naming Azure and Tri-County as co-plaintiffs filed 2010‑12‑22 (6:10‑cv‑00681) — ~3.7 months, comfortably inside the six-month window. Law-firm reporting confirms the sequence directly: "In 2010, Azure Networks donated the asserted patent to co-plaintiff Tri-County, an Eastern District of Texas charity… Shortly after making the donation, Azure and Tri-County entered into a license agreement that granted back to Azure an exclusive right to practice the invention, as well as the exclusive right to enforce the patent." (Akin Gump IP Newsflash, 2014‑11‑14; Finnegan Last Month at the Federal Circuit, Dec. 2014.) The charity structure was used to anchor venue in the Eastern District of Texas — a district court even heard argument that "Tri-County was created just to secure venue in the Eastern District of Texas" (Azure Networks, LLC v. CSR PLC, 2013‑1459).

6. Bankruptcy fire-sale — NOT PRESENT

No Chapter 7/11 filing by BBNT Solutions LLC or BBN Technologies Corp. appears in the record. BBN went operating → merged (2006) → acquired by Raytheon (2009), i.e., a solvent acquisition, not a bankruptcy. The 2009 divestiture of this family is better characterized as pre-acquisition portfolio housekeeping than a distress sale.

7. Privateering — NOT PRESENT / UNCLEAR

No SEC filing, court filing or press coverage was found showing that BBN or Raytheon directed, funded, or shared in Stragent's/Azure's assertions. The chronology cuts against it: the family was recorded out of BBN on 2009‑08‑19, before Raytheon's acquisition of BBN (Oct. 2009), so Raytheon never held these assets. Mark as not present on the evidence available.

8. Defensive aggregator — NOT PRESENT

The chain terminates at III Holdings 1, LLC, an Intellectual Ventures acquisition vehicle, which is an asserting entity, not RPX / AST / LOT / Unified / OIN. Nothing here indicates neutralization; on the contrary, Unified Patents later had to file IPRs against III Holdings 1 patents (e.g., US 7,702,781).

Verdict

NPE — high confidence

Justification: this is a textbook cascade out of an operating research contractor into an assertion chain — BBN Technologies Corp. → Stragent, LLC (2009‑08‑19) → Power Mesh Networks, LLC (2008‑10‑10) → Azure Networks, LLC (2009‑10‑07) → Tri-County Excelsior Foundation (2010‑09‑01), with the charity transfer landing ~3.7 months before the 2010‑12‑22 filing of E.D. Tex. 6:10‑cv‑00681 (Azure/Tri-County v. TI, Atmel, Freescale, Microchip, NXP) — and it terminates at III Holdings 1, LLC (2014‑06‑24), publicly identified as an Intellectual Ventures subsidiary. Three independent strong signals are satisfied (shell-entity transfer, known asserter at both ends of the chain, pre-litigation transfer), plus cascading transfers and a 2013‑08‑14 four-record chain-of-title repair consistent with the Federal Circuit standing fight over the sibling '129 patent. The one signal that would sharpen this analysis — repeat correspondent of record — could not be retrieved and is flagged as a data gap rather than resolved either way.

Verify at: https://assignmentcenter.uspto.gov/ and https://assignment.uspto.gov/patent/index.html — search patent number 7020501 (or application 09/998,946) to obtain the reel/frame numbers and correspondent names omitted above, and confirm whether the 2013‑08‑14 confirmatory/name-change records actually name this patent versus a family sibling.

I'll analyze US patent 7020501 and its prior art. Let me search for authoritative sources.

Let me gather details on the specific prior art references cited in the patent.

Prior-Art Analysis — U.S. Patent No. 7,020,501 B1

"Energy efficient forwarding in ad-hoc wireless networks"

• Patent No.: US 7,020,501 B1 (interpreted literally)
• Application No.: US 09/998,946
• Inventors: Brig Barnum Elliott; David Spencer Pearson
• Original Assignee: BBNT Solutions LLC (later BBN Technologies Corp.; current assignees listed as OSO IP LLC / III Holdings 1 LLC)
• Priority/Filing Date: 2001-11-30; Granted/Published: 2006-03-28
• Status: Expired – Lifetime (adjusted expiration 2023-08-09)
• Source: https://patents.google.com/patent/US7020501/en

Scope of the claims being mapped (literal): Claims 1, 4, 5 (inbound powering-on schedule → selective Tx/Rx power-on → produce a second schedule → transmit it onward); claims 2–3 (ad-hoc multi-node/sensor network); claims 6–9 (tier hierarchy + Tx/Rx scheduling messages between adjacent tiers); claims 10–15 (intermediate node receiving a scheduling message specifying a first schedule and a second schedule); claims 16–18 (data structure of affiliated children IDs + Tx/Rx schedules); claim 19 (receiving presence messages, determining two schedules, transmitting them).

Section 1 — The eight U.S. patent citations of record

The patent's own "Patent Citations (8)" list (all marked * cited by examiner) is:

1. US 6,192,230 B1 — "Wireless data communication system having power saving function" (Lucent Technologies)

• Dates: priority 1993-03-06; published 2001-02-20.
• Description: Discloses a wireless LAN with battery-powered mobile stations and an access point (and, in a second embodiment, an "ad-hoc" network of FIG. 8–12 in which one station assumes a master role). The master broadcasts synchronizing messages (PSYNC) on a synchronization timer while slave stations remain awake; on receipt slaves enter a doze state. Stations with traffic transmit traffic-indicator messages (PTIM) in the synchronized awake window just before the next synchronizing message. Power to the transceiver is switched by a doze timer/power-management circuit. (Sources: https://patents.google.com/patent/US6192230 ; EP 0 615 364 B1 counterpart.)
• Potential §102 relevance: Directed squarely at synchronized power-on/power-off scheduling driven by a message from another node — the core of claims 1, 4, 5 and the "powering-on/powering-off based on a schedule" concept of claims 10, 14, 15. The ad-hoc embodiment touches claim 2. Anticipation is nevertheless doubtful: it does not clearly show the claim-1/4/5 element of a receiving node producing a second (derived) schedule and transmitting it onward, nor the tier-hierarchy of claims 6–9. It is therefore stronger as §103 art.

2. US 6,292,508 B1 — "Method and apparatus for managing power in a frequency hopping medium access control protocol" (Proxim, Inc.)

• Dates: priority 1994-03-03; published 2001-09-18.
• Description: Manages power in a frequency-hopping wireless network of nodes. The system is initialized by synchronizing the nodes to a first node; a node is then placed into "an inactive state of reduced power consumption," saving timing information of the first node. The transmitter is powered only during actual transmission; receivers may be off for a substantial portion of time while still ensuring communications are received. Frames destined for a sleeping node are buffered, and a wakeup signal indicates which nodes have buffered traffic. Claim 8 sends a synchronization signal indicating a hop number and hop time remaining. (Sources: https://patents.google.com/patent/US6292508 ; FreePatentsOnline 6292508.)
• Potential §102 relevance: Strong conceptual overlap with claims 1, 4, 5 (selectively powering transmitters/receivers on and off under control of another node) and with claims 10–15 (receiver powered on to listen for a message and powered off based on timing derived from that message; wakeup signaling). It also concerns self-organizing peer/ad-hoc operation (claims 2, 19). Again, the forwarding of a derived second schedule to further nodes (claims 1/4/5) is not clearly shown, so §103 is the more realistic ground.

3. US 5,583,866 A — "Method for delivering broadcast packets in a frequency hopping local area network" (Motorola, Inc.)

• Dates: priority 1994-12-05; published 1996-12-10.
• Description: A method for delivering broadcast packets in a frequency-hopping LAN. As cited, it is directed to broadcast delivery/scheduling in a frequency-hopped LAN rather than to sleep-scheduling per se.
• Potential §102 relevance: Only marginal. It could bear on the broadcast/message distribution aspects of claims 19 and 6 (distributing scheduling content as broadcasts), but I cannot identify any claim for which it alone would supply every element. Best regarded as background art.

4. US 6,564,074 B2 — "Power management method of and apparatus for use in a wireless local area network (LAN)" (Hewlett-Packard Co.)

• Dates: priority 1997-10-03; published 2003-05-13.
• Description: Power-management scheme for wireless-LAN stations (doze/awake duty-cycling of the radio under a coordinated power-management regime).
• Potential §102 relevance: General teaching of selectively powering a wireless station's transceiver on and off — relevant background to claims 1, 4, 5, 10. Like the other LAN references, it does not appear to disclose the tiered, multi-hop, schedule-forwarding architecture of the challenged claims, again pointing to §103 rather than §102.

5. US 6,208,247 B1 — "Wireless integrated sensor network using multiple relayed communications" (Rockwell Science Center, LLC)

• Dates: priority 1998-08-18; published 2001-03-27. Inventors include J. R. Agre, L. P. Clare, H. O. Marcy, A. J. Twarowski, W. Kaiser, et al.
• Description: Miniature low-power sensing stations each with sensor(s), a digital signal processor, a microprocessor, and a wireless transceiver, organized into a communicating network using multiple relayed (multi-hop) transmissions from station to station. The specification expressly discusses the need to conserve energy ("an individual wireless sensor station requires a limited, self-contained power supply, which usually dictates that it conserve energy"), the difficulty of learning network topology when stations are randomly placed, and scheduling multi-hop communications. The microprocessor operates at low power until a comparator output exceeds a threshold. (Sources: https://patents.google.com/patent/[US6208247B1](/patent/US6208247B1) ; patentimages US6208247.pdf.)
• Potential §102 relevance: This is the closest sensor-network reference of record and the most serious threat to the "sensor network" and tiered-routing claims. It supplies: a wireless multi-hop sensor network (claims 2, 3, 6, 7) and relayed forwarding toward a collection point. Because it does not clearly set out hierarchical tiers of nodes each receiving/forwarding derived powering-on schedules from an adjacent lower tier (claims 1, 4, 5, 10–15), I assess it as §103 art for those claims, and as a potential §102 reference for the broad "wireless sensor network" claims (2, 3) and possibly elements of claim 6.

6. US 6,414,955 B1 — "Distributed topology learning method and apparatus for wireless networks" (Innovative Technology Licensing, LLC)

• Dates: priority 1999-03-23; published 2002-07-02.
• Description: A wireless network of communicating devices (preferably sensors) uses a distributed method of topology learning to organize multiple-hop, relayed communication among devices. It identifies communication neighbors and interference neighbors for each device (preferably using ranging and distributed calculation), limits the number of devices involved in each step, and thereby conserves energy and bandwidth. It expressly facilitates scheduling of communications in any of a variety of multiple-access protocols, is scalable with no inherent limit on network size, and supports adding/removing nodes. (Sources: EP 1 039 689 A2/A3 counterpart, applicant Rockwell Science Center, inventors Clare and Agre; https://patentimages.storage.googleapis.com/07/bd/c1/ed952b08123cee/EP1039689A2.pdf .)
• Potential §102 relevance: Highly relevant to the self-organization into a hierarchy and the distributed scheduling of transmissions of claims 6–9, and to the neighbor/affiliation data structures of claims 16–18. Its stated goals — energy conservation and distributed scheduling for a scalable sensor network — map onto the problem the '501 patent addresses. The specific "first/second powering-on schedule" format and the derived-schedule forwarding are not clearly disclosed, so claims 1–5 and 10–15 are better attacked under §103.

7. US 6,694,149 B1 — "Method and apparatus for reducing power consumption in a network device" (Motorola, Inc.)

• Dates: priority 1999-12-22; published 2004-02-17.
• Description: Reduces power consumption in a network device (radio duty-cycling / power-save operation).
• Potential §102 relevance: General teaching of power-saving receiver/transmitter control — background to claims 1, 4, 5, 10. I could not confirm claim-specific disclosure from the sources retrieved; treat as §103/background.

8. US 6,381,467 B1 — "Method and apparatus for managing an ad hoc wireless network" (Motorola, Inc.)

• Dates: priority 2000-06-22; published 2002-04-30.
• Description: Managing an ad-hoc wireless network (network formation/management and coordinating the participating devices).
• Potential §102 relevance: Bears on the ad-hoc, multi-node network limitation of claims 2 and 6, and generally on organized operation of ad hoc nodes (claim 1 preamble, claim 19). Its handling of per-node transmit/receive scheduling and tiering is, based on the citations available to me, less specific than US 6,208,247 and US 6,414,955; treat as §103/background.

Section 2 — The five non-patent citations of record

All are marked * cited by examiner. As listed by Google Patents:

1. Clare, Loren P. et al., "Self-Organizing Distributed Sensor Networks," University of California Los Angeles / Rockwell Science Center, Mar. 7, 2001 (print date), 9 pages. — By the same Rockwell/UCLA group as US 6,208,247 and US 6,414,955. Directly addresses self-organizing distributed sensor networks, i.e., the tiered/self-organizing premise of claims 6–9 and the "organizing nodes into tiers" step. Potentially the most dangerous art to claims 6–9; its print date (March 2001) precedes the '501 filing (Nov. 30, 2001).
2. Doherty, Lance, "Algorithms for Position and Data Recovery in Wireless Sensor Networks," Univ. of California at Berkeley, Mar. 7, 2001 (print date), 54 pages. — Sensor-network data recovery / position algorithms; background to the sensor-network aspects (claims 2, 3, 6).
3. Liu et al., "Simulation Modeling of Large-Scale Ad-hoc Sensor Networks," European Simulation Interoperability Workshop, Univ. of Westminster, London, Jun. 25–27, 2001, 12 pages. — June 25–27, 2001 is after the '501 priority date (Nov. 30, 2001)? No — it is before Nov. 30, 2001, so it can qualify as prior art; large-scale ad-hoc sensor network modeling (claims 2, 6).
4. Robert E. Van, "Distributed Sensor Processing over an Ad Hoc [network]," NIST. — Distributed sensor processing in ad hoc networks; background to claims 6 and 19.
5. Young Liu, Myung Lee, "Bluetooth Scatternet Route Structure," IEEE. — Hierarchical (scatternet) route structure; background to the tier-hierarchy concept of claims 6–9.

Section 3 — Consolidated claim-by-claim view (best-effort; §102 where a single reference plausibly supplies all elements, otherwise §103)

Section 4 — Explicit caveats (per the operating rules)

• I am an analyst, not the examiner. The mappings above are a technical relevance assessment of the references as cited on the face of US 7,020,501, not a record of any USPTO §102 rejection. The prosecution history was not retrieved, so I cannot state which references the examiner actually applied.
• Anticipation standard. §102 anticipation requires a single reference disclosing every element, arranged as in the claim. Most of the cited references are single-hop or centrally-scheduled LAN systems and do not plainly disclose the '501 patent's distinctive hierarchical derived-schedule forwarding (claims 1, 4, 5, 10–15). My best judgment is that the strongest §102 exposure is on the broad/structural claims (3, possibly 2 and 6–9) via US 6,208,247 and US 6,414,955 (and the Clare et al. NPL), with the remainder being §103 territory.
• Literal identifiers. All patent numbers are reproduced exactly as they appear in the "Patent Citations (8)" and "Non-Patent Citations (5)" sections of the Google Patents record for US 7,020,501 (e.g., US6192230B1, US6292508B1, US5583866A, US6564074B2, US6208247B1, US6414955B1, US6694149B1, US6381467B1). I have not normalized or "corrected" any of them.
• Confidence levels. Descriptions for US 6,192,230, US 6,292,508, US 6,208,247, and US 6,414,955 are grounded in retrieved documents (URLs given inline). Descriptions for US 5,583,866, US 6,564,074, US 6,694,149, and US 6,381,467, and for the NPL items other than Clare et al., are lower-confidence (based on the citing metadata and general knowledge) — I could not, within the available searches, retrieve each full text, and I flag them as such rather than assert unverified detail.
• Family note. The '501 patent shares a priority date (2001-11-30) with a family that includes US 7,421,257 B1, US 7,623,897 B1, US 7,979,096 B1, US 7,979,098 B1, US 9,674,858 B2, US 10,588,139 B2, and US 10,863,528 B2 (and publication US 2015/0029914 A1). These are later family members/continuations rather than prior art to the '501 patent.

Primary sources:

• https://patents.google.com/patent/US7020501/en (authoritative full text and citation list)
• https://patents.google.com/patent/US6192230
• https://patents.google.com/patent/US6292508
• https://patents.google.com/patent/US6208247B1
• EP 1 039 689 A2/A3 (counterpart disclosure of US 6,414,955, Rockwell Science Center)

I'll ground the analysis by verifying what the cited references actually disclose before constructing combinations. Let me pull details on the key ones.

Obviousness Analysis — U.S. Patent No. 7,020,501 B1 under 35 U.S.C. § 103

Note on scope. This section builds on the bibliographic and claim summaries already generated (which I do not repeat). It uses only the prior-art materials appearing on the patent page's "Patent Citations (8) / Non-Patent Citations (5)" sections, plus the "Cited By" tables where needed to disqualify material. I could not retrieve the prosecution history (file wrapper) or the full text of every reference, so disclosure-level statements below carry explicit confidence tags. Where a search result contradicted the page's own dating, I flag it.

1. Governing framework and presumptions

Caveat on the record. I have no evidence of any Graham secondary consideration (unexpected results, long-felt need, licensing-due-to-merits nexus) being asserted for the '501 patent. The assignment chain and the 2010 E.D. Tex. suit discussed in the litigation summary reflect commercial activity, but without nexus evidence that is weak and typically discounted.

2. The prior-art universe on this page — what counts and what does not

This is the most important threshold step, because the page presents 105 and 198 "Cited By" entries that can look like prior art.

Excluded (not prior art):

• Every entry in the two "Cited By" tables. The earliest priority date across those tables is 2002-05-23 (Hester/Motorola, US 2003/0231597 A1 and US 2004/0042501 A1). Nothing in either cited-by table predates 2001-11-30, so none can be § 102(a), § 102(b), or § 102(e) art against this patent. The 2026-era items (CalAmp, Ball Aerospace, Northrop Grumman) are plainly irrelevant.
• Family members appearing in the cited-by tables — US 7,979,096; US 7,979,098; US 9,674,858; US 10,588,139; US 10,863,528; and US 11,445,523 — share the 2001-11-30 priority. Not prior art.
• US 2006/0229083 A1 (BBN, "Methods and apparatus for reduced energy communication in an ad hoc network") — priority 2004-12-17; post-dates. Also listed in a "cited by" position only.
• Co-pending application Ser. No. 09/999,353 (incorporated by reference in the '501 spec, filed 2001-11-15, same assignee). Even if it later published, pre-AIA § 103(c) disqualifies commonly owned § 102(e)/(f)/(g) art from an obviousness rejection. So it is not a viable § 103 reference. I flag this because a challenger might otherwise be tempted to use it.

Available (the real prior art set): the 8 patent citations and the 5 non-patent citations listed on the page. Their qualification status:

⚠ Flagged contradiction with the earlier section. The Google Patents page lists Clare et al. with the parenthetical "Mar. 7, 2001 (print date)." My search results show the paper was actually presented April 5–9, 1999 and published in SPIE Vol. 3713 (1999) (DOI 10.1117/12.357138; also cited in a later WINS patent as "SPIE 13th Annual Symposium … pp. 1–9, Apr. 5–9, 1999"). The "Mar. 7, 2001" figure appears to be a retrieval/print date, not the publication date. Per my operating rules I follow the search results: R3 is 1999 art and therefore § 102(b), not merely § 102(a). Either way it predates the priority date, so qualification is unaffected — but the subsection matters for how a challenger pleads it. Sources: https://www.mendeley.com/catalogue/3805c5c7-525b-3ab5-b75a-830aa4710af3/ ; https://patentimages.storage.googleapis.com/8f/14/00/c039c269ef7b8e/[US8832244](/patent/US8832244).pdf

3. What the verified references actually teach (disclosure dossiers)

R1 — US 6,208,247 (Rockwell). "Wireless integrated sensor network using multiple relayed communications." Retrieved text is unusually on-point. It expressly identifies the motivation:

"an individual wireless sensor station requires a limited, self-contained power supply, which usually dictates that it conserve energy."
"Wireless communication among large numbers of densely placed sensor stations requires sophisticated multiplexing or scheduling to avoid cross-interference. If the stations are placed randomly … it is difficult to learn the topology of the network so that multi-hop communications (communications relayed among multiple stations) may be scheduled."

→ R1 supplies (a) the multi-hop relayed sensor-network architecture, (b) the battery-conservation problem statement, and (c) an express linkage between topology learning and the scheduling of multi-hop communications. Source: http://patentimages.storage.googleapis.com/2f/40/9c/435902511777d5/US6208247.pdf

R2 — US 6,414,955 / EP 1 039 689 A2 (Rockwell). "Distributed topology learning method and apparatus for wireless networks." Retrieved text: distributed, decentralized topology learning that "identifies interference neighbors and communication neighbors for each device," using TDMA time-slot channel reuse, "thereby conserving energy and bandwidth," and expressly "facilitates scheduling of communications in any of a variety of multiple access protocols." It targets "a network of low power wireless nodes in which many of the nodes have a limited power source (such as a battery or a solar powered source)." The EP 1 039 689 A2 abstract (published 2000-09-27) carries the same disclosure, giving a § 102(b) printed-publication date. Sources: https://patents.google.com/patent/[US6414955B1](/patent/US6414955B1) ; EP 1039689 A3 PDF (patentimages.storage.googleapis.com/37/13/2f/27909cd6cb5bb6/EP1039689A3.pdf)

R3 — Clare, Pottie & Agre (SPIE 1999). Self-organizing microsensor networks that "bootstrap and dynamically maintain organizational structure … without the need for human assistance," evolving "so as to achieve these functions via low power operation," developed under DARPA AWAIRS. → hierarchical self-organization + low-power operation. Source: https://www.mendeley.com/catalogue/3805c5c7-525b-3ab5-b75a-830aa4710af3/

R4 — US 6,192,230 (Lucent). Battery-powered stations whose transceiver is switched on/off by a doze timer and power-management circuit; an access point or master station broadcasts synchronizing messages and traffic indicator messages; mobile stations alternate between "doze" and "awake" per a timing scheme; FIG. 8 embodiment is expressly "a so-called 'ad-hoc' network" in which one station acts as master and broadcasts PSYNC, and other stations transmit traffic indicators in a synchronized awake period. Claims 10–16 recite the ad-hoc master/slave variant. Source: https://patents.google.com/patent/US6192230 ; EP 0615364 B1.

R9 — US 6,694,149 (Motorola). A network device is "placed in a quiescent mode and scheduled to switch to an active mode at a scheduled time"; on wake it receives a control message; if no data, it "sets a new scheduled time and returns to the quiescent mode." Groups are defined and control messages "identify an active set." → a node receives a scheduling/control message and derives its next wake time from it. Source: https://patents.google.com/patent/[US6694149B1](/patent/US6694149B1)

R5 / R6 / R7 / R8 / R10 / R11 / R12 — titles and dates only. I could not retrieve full text within the search budget. Based on title and date they are cumulative to R4/R9 (MAC-layer power management; FH-LAN broadcast delivery; ad-hoc network management; WLAN power management; sensor-network localization/simulation; scatternet routing). I will not assert specific disclosures for these and do not rely on them below, except as corroboration of the general state of the art.

4. Claim-by-claim obviousness analysis

4.1 Claim 1 (and its apparatus/CRM twins, claims 4 and 5)

Claim 1 elements → mapping:

Proposed combination: R4 + R1 + R2 (optionally + R9, + R3).
Motivation: R1 itself states the problem — limited self-contained power supplies "dictate that they conserve energy," and multi-hop communications "may [need to] be scheduled" once topology is learned. R2 teaches that distributed topology learning "conserves energy and bandwidth" and "facilitates scheduling of communications." A POSITA seeking to extend sensor-node lifetime would be led to the coordinated duty-cycling of R4 and to the distributed, self-organizing schedule distribution of R2, and would apply them to the relayed multi-hop architecture of R1. Under KSR, combining a known multi-hop relay architecture with a known coordinated sleep/wake mechanism, to achieve the known benefit of reduced energy consumption, is a predictable use of prior-art elements for their established functions.

Assessment: Strong § 103 case. The only element requiring more than one reference's teaching is "producing a second schedule … and transmitting it," which R9 (derive next wake time) + R2 (derive own schedule from distributed topology) together supply.

4.2 Claims 2 and 3 (dependents)

• Claim 2 (ad-hoc, multi-node wireless network): R4's FIG. 8 ad-hoc embodiment and the ad-hoc subject matter of R1/R3/R11. Obvious.
• Claim 3 (wireless sensor network): R1, R2, R3, R10, R11. Obvious — and R1/R3 make it near-anticipatory of the field alone.

4.3 Claim 6 (conveying messages) and dependents 7–9

Proposed combination: R1 + R2 + R4 (+R3).
Claim 7 (scheduling messages = power-on/off time schedules): met by R4/R9.
Claim 8 (destination = data collection point): R1 discloses sensors reporting to a central processing/collection location (and criticizes central processing's reliability, not its existence — a POSITA would retain the sink concept).
Claim 9 (collection point in the lowest tier): an arbitrary architectural placement — design choice; the "tier 0 = sink" arrangement is the natural consequence of the hop-count hierarchy of R2/R1.
Assessment: Strong.

4.4 Claims 10, 14, 15 — the intermediate-node claims (the § 103 friction point)

These claims require a single scheduling message from the second node that specifies (i) the first↔second node schedule and (ii) the schedule on which the first node may communicate with each of its own downstream nodes.

What the prior art of record supplies:

• R4/R9 — receiving a message that dictates the node's own awake/doze (or active/quiescent) intervals. → covers (i) and the "selectively power on/off based on the schedule" step.
• R2 — a node learns both its communicating set and its interfering set, and this "facilitates scheduling of communications," i.e., the node's transmission opportunities relative to both its upstream and downstream neighbors in a TDMA frame. In a slotted multi-hop TDMA network of the kind R2 describes, a single frame schedule inherently encodes both the child→parent slots and the parent→grandchild slots.
• R1's background — scheduling multi-hop communications requires knowing the topology; the natural protocol consequence is a schedule distributed from the sink downward.

Proposed combination: R4 + R2 (+ R1).
Motivation: (a) to eliminate the overhead and energy cost of the node waking separately to discover and then schedule downstream transmissions, a POSITA would consolidate the node's own link time and its children's allotted times into the schedule message it already receives and re-broadcasts; (b) R2 supplies the distributed-scheduling framework in which such consolidation is natural; (c) KSR's "design incentive … to improve" and "predictable variation" rationales apply to consolidating two schedule fields into one message.

Assessment: Moderate, not strong. If any reference expressly discloses a single message carrying both the parent-link and the child-link schedules, I have not found it in the verified set, and I will not assert one. A challenger must argue obviousness of the consolidation itself. That is a reasonable argument (overhead reduction was a recognized goal — R2 expressly frames itself around "conserving energy and bandwidth"), but it is the thinnest part of the case, and it is precisely where a patentee would focus its rebuttal.

Cross-reference to a flagged issue from the earlier section: claims 12 and 13 use a tier convention (transmitting data "to … a lower tier," scheduling messages "to … a higher tier") that runs opposite to FIG. 3's illustrated convention. If claim 13 is read literally, it recites a node sending schedules upward, which the verified prior art of record does not clearly show. This is the one claim family where the on-face claim text, rather than the reference set, may do the work.

4.5 Claim 16 and dependents 17, 18 (data structure)

Proposed combination: R9 + R2 (or R4 + R2).
Motivation: once the affiliation/neighbor-identification function of R2 and the scheduled-wake function of R4/R9 are combined (as in §4.1), the record layout that stores "who my children are" plus "when I transmit to them" plus "when they transmit to me" is the direct, expected implementation — a mere design choice / arrangement of data flowing from the combined functionality, not a patentably distinct advance. KSR and the "design choice" line of authority support this.
Assessment: Strong on § 103. (Separate, non-§103 note: claim 16 is also exposed on § 101 grounds as a data structure per se, but that is outside this task's scope.)

4.6 Claim 19 (parent-side schedule construction)

Mirror image of claim 10. Elements: receive presence messages from neighbors; determine (i) a first schedule for communicating with each neighbor and (ii) a second schedule for each neighbor to communicate with other nodes; transmit a message including both schedules.

Proposed combination: R9 + R4 + R2.

• R9: a coordinating entity "periodically transmit[s] … group control message[s] … identifying an active set," and devices are "scheduled to switch to an active mode at a scheduled time" — i.e., the coordinator determines schedules and messages them out.
• R4: the AP/master determines and broadcasts the synchronizing/traffic-indicator schedule to mobile/ad-hoc stations, which is functionally "a first schedule for communicating with each of the neighboring nodes."
• R2: the distributed topology-learning framework supplies both the presence/neighbor identification step and the second schedule (each node's opportunity to communicate with its own neighbors), expressly "facilitat[ing] scheduling of communications."
  Motivation: Same as §4.5 — the coordinator needs to tell each child not only when to talk to it, but when to talk to the grandchild tier, so that the TDMA frame is conflict-free (R2's interference topology). Consolidating both into one message reduces the number of wake-ups, directly serving the energy-conservation purpose stated in R1/R2/R3.
  Assessment: Moderate-to-strong, sharing the single-message limitation risk identified for claim 10.

5. Consolidated motivation-to-combine (KSR rationales)

1. Same field of endeavor / common problem. All eight patent citations and all five NPL items are wireless networks, with R1/R2/R3/R10/R11 in sensor networks and R4/R5/R6/R8/R9 in battery-powered wireless MAC/power management. KSR recognizes combination of references addressing the same problem.
2. The problem was expressly articulated in the art. R1 states verbatim that self-contained sensor power supplies "usually dictate that they conserve energy" and that multi-hop communications must be scheduled. That supplies the reason to look to R4/R9's coordinated sleep scheduling.
3. Predictable solution to a known problem. Duty-cycling a transceiver is the canonical, finite answer to battery depletion; the only engineering question is coordination, and coordinated scheduling messages were well known (R4, R9). KSR: "a finite number of identified, predictable solutions."
4. Design incentive / market force. "Research … directed towards the building of networks of distributed wireless sensor nodes" (the '501 spec's own Background) and the DARPA AWAIRS low-power mandate (R3) created strong pressure to extend node operational life.
5. No teaching away. R4 affirmatively embraces an ad-hoc, master-coordinated embodiment; R2 is expressly for low-power multi-hop wireless nodes with battery/solar supplies. Nothing in the record teaches away from relaying schedules over multiple hops.
6. Critical date integrity. All relied-upon references are dated before 2001-11-30, with several qualifying under § 102(b) outright (R3 — 1999; R6 — 1996; R2 via EP 1 039 689 A2 — 2000-09-27; R4 via EP 0 615 364 B1 — 1994).

6. Where the obviousness case is weak

1. Claims 10 / 14 / 15 / 19 — the single-message, dual-schedule limitation. The verified record does not contain a reference expressly teaching one message that carries both the node↔parent schedule and the node↔children schedule. The rejection must rest on the combination plus a rationale for consolidating the fields. This is the strongest non-obviousness argument available to the patentee.
2. Claim 13's tier direction. The on-face claim text ("scheduling messages to the second node in a higher tier") does not match FIG. 3's convention and may not be met by the cited art as literally read. (Building on the inconsistency flagged in the earlier section.)
3. Claim 1's "producing a second powering-on schedule." If construed to require generation of a new, downstream schedule rather than merely storing/repeating the parent's, the case narrows to R9 + R2 and becomes contestable.
4. Evidentiary gaps. I could not verify the disclosures of R5, R6, R7, R8, R10, R11, or R12, and I have no prosecution history. Any real validity challenge should chart each reference's actual disclosure (not merely its title), and should specifically look for art in the 802.11 power-save / HIPERLAN families and in the broader WINS portfolio (US 6,735,630; 6,826,607; 6,832,251; 6,859,831 — all post-date the '501 priority and are therefore not available, but the pre-2001 WINS/SPIE material is a fertile hunting ground).
5. Antecedent-basis wrinkle in claim 5 (previously noted): a § 112 issue, not § 103, but it can affect how the claim is construed in any obviousness analysis.

7. Bottom line

Confidence. High for the § 102 status and content of R1, R2, R3, R4, and R9 (full text or abstract retrieved and quoted). High for the disqualification of the "Cited By" material as prior art (all post-date 2001-11-30 or are family members). Medium for the overall § 103 conclusion, which is inherently a judgment call without a full prior-art search or the prosecution history. Low for any statement about R5–R8, R10–R12 disclosures beyond their titles and dates — those I did not verify and do not rely on.