US 8030884

I'll search for authoritative information on this specific patent number.

Let me check for CAFC 2026 dockets and the litigation details.

Let me check the 2026 case and any Federal Circuit activity.

US Patent 8,030,884 — Analyst Summary

Important scoping note first: The number you gave, 8030884, maps literally to US 8,030,884 B2. I found no other patent numbered 8030884 in the results, and the hits below are all for that exact document. One caveat on the date: your prompt says today is April 26, 2026, but the docket and patent records I retrieved carry timestamps of May 5, 2026 and September 30, 2026. I am reporting the records as returned rather than "correcting" them, but you should be aware of that inconsistency.

1. Bibliographic data

Chain of title (per Google Patents legal events, as listed): General Electric Co. → GE Intellectual Property Licensing, LLC (Mar. 26, 2025) → Dolby Intellectual Property Licensing, LLC (Mar. 26, 2025, change of name) → Edison Innovations, LLC (Feb. 20, 2025 per the listed event) → Bunker Hill Technologies, LLC (quitclaim assignment, Apr. 9, 2026). The Feb./Mar. 2025 ordering in the source feed is internally inconsistent, so treat the intermediate-date sequence with caution; the terminal owner is stated as Bunker Hill Technologies, LLC.

Family: Continuation US 8,487,582 B2 (app. 13/099,053, filed May 2, 2011, granted July 16, 2013); EP 2290778 B1; CN 102005789 B; JP 6068778 B2 and JP 6228586 B2. Foreign filings claim the Aug. 31, 2009 priority.

Cited prior art (examiner-cited, 9 refs): US 5,373,195; US 5,589,743; US 5,903,449; US 6,331,365; US 6,737,822; US 7,049,792; US 7,595,597; US 7,750,501; US 7,499,296.

2. Abstract (verbatim)

"An apparatus comprises a first energy storage device configured to output a DC voltage, a first bi-directional voltage modification assembly coupled to the first energy storage device, and a charge bus coupled to the first energy storage device and to the first bi-directional voltage modification assembly. The apparatus also comprises high-impedance voltage source coupleable to the charge bus and a controller configured to monitor a transfer of charging energy supplied from the high-impedance voltage source to the first energy storage device. The controller is also configured to compare the monitored transfer of charging energy with a threshold value and, after the threshold value has been crossed, control the first bi-directional voltage modification assembly to modify one of a voltage and a current of the charging energy supplied to the first energy storage device."

3. Plain-language overview of the independent claims

The patent is about reusing a vehicle's existing traction drive electronics (inverter, DC/DC converters, motor windings) as part of the battery charger, so a separate on-board charger is unnecessary. All three independents share a two-stage charging concept: Stage 1 is uncontrolled/impedance-limited direct charging through diodes; once a monitored quantity crosses a threshold, Stage 2 begins with active converter control.

Claim 1 — Apparatus (the base claim)
An apparatus with: (a) a first energy storage device outputting DC; (b) a first bi-directional voltage modification assembly coupled to it; (c) a charge bus coupled to both; (d) a high-impedance voltage source connectable to the charge bus; and (e) a controller that (i) monitors charging-energy transfer from the source into the storage device, (ii) compares that monitored transfer to a threshold value, and (iii) after the threshold has been crossed, controls the bi-directional assembly to modify the charging energy's voltage and/or current.
Key scope point: the threshold comparison plus the post-threshold hand-off to active control is the heart of the claim. Claim 1 does not itself limit the threshold to current or voltage — that comes in dependents.

Claim 16 — Method
A method of transferring energy between an on-board storage device and an external source: coupling a battery (DC output) to a first voltage bus; coupling a first bi-directional voltage modification assembly to that bus; coupling a second voltage bus to the first bus so the second bus receives charging energy from a high-impedance source and supplies it either to the modification assembly or to the first bus; and configuring a controller to monitor the transfer, compare to a threshold, and after the threshold is crossed control the assembly to modify voltage/current delivered to the battery.

Claim 20 — System
A system with a charge bus receiving charging energy from a voltage source; an energy storage device outputting DC and coupled to the charge bus; a first bi-directional voltage modification assembly coupled to the charge bus; and a controller that monitors the transfer, compares it to a threshold comprising one of (a) a voltage of the energy storage device and (b) an average rectified line voltage of the charge bus, and after the threshold is crossed, controls the assembly to modify voltage/current.
This is the claim asserted in litigation (see §4) and is narrower on its face than claim 1 because it names the threshold options.

Notable dependent claims:

• 2/17/22 — first assembly is a bi-directional DC-AC inverter; controller boosts voltage/current. Claim 2 recites the storage device as "a high power energy storage device having an instantaneous acceptance capability larger than an instantaneous delivery capability of the high-impedance voltage source."
• 7/18/23 — first assembly is a bi-directional DC-DC converter; controller bucks voltage/current. Claim 7/13 recite the storage device as "a low power energy storage device…" Claim 13 adds the inverse capability relationship (acceptance capability smaller than the source's delivery capability) and a "pre-determined value" buck target. Note the claim set uses "high power" (claim 2) and "low power" (claims 7, 13) with overlapping capability language — read those limitations literally, not as a typographical error to be normalized.
• 8 — a switch/contactor that directly couples the low-power storage device to the charge bus in closed position and de-couples it in open position, with the controller opening it after the threshold is crossed.
• 4 — the controller drives multiple boost converters of the inverter at the same phase (torque-ripple reduction).
• 5 — inverter diodes carry charging current before the threshold is crossed.
• 11 — controller simultaneously charges the low-power and high-power storage devices.
• 14 — energy storage, modification assembly, and controller are all on a vehicle.
• 15 — source may be single-, two-, three-, or six-phase.
• 24 — housing may be a vehicle, crane, elevator, or lift.

Specification mechanics that back the claims (FIGS. 1–3): Stage 1 current flows from the external high-impedance (transformer-isolated) source through a rectifier (66) or through inverter diodes (82–86, or 82–92 in FIG. 3), through motor windings 44–48, into the charge bus 16. Because the motor/traction battery's instantaneous acceptance exceeds the source's delivery capability, Stage 1 is limited essentially by source impedance — "rapid" charging with no initial current control by switching devices. Once the controller (56) sees the monitored current (sensor 94) or voltage (sensors 124/130) cross a pre-set threshold, Stage 2 engages the half-phase modules as boost converters (inverter) or as buck converters (DC/DC), with the motor windings acting as boost inductors.

4. Enforcement / litigation status (as retrieved)

No Federal Circuit (CAFC) 2026 docket for the '884 was found. I searched for a 2026 CAFC appeal tied to this patent/owner and returned no results. Absence of a hit is not proof of absence, but I have no authoritative CAFC record to report.

District court activity — both cases are by the current owner, Bunker Hill Technologies, LLC, in E.D. Tex.:

1. BUNKER HILL TECHNOLOGIES, LLC v. Toyota Motor Corporation et al., No. 2:25-cv-01133 (E.D. Tex.), filed Nov. 18, 2025. Asserted patents include 8,030,884 plus 8,086,364; 8,326,467; 9,914,365; 10,291,158; 10,374,529; 10,442,296; 10,549,648; 11,374,508. Defendants: Toyota Motor Corporation, Toyota Motor North America, Inc., Toyota Motor Sales, U.S.A., Inc.

   • Complaint infringement chart for the '884 maps independent claim 20 onto Toyota vehicles: high-voltage harness = charge bus; hybrid battery = energy storage device; bi-directional DC/DC converter = bi-directional voltage modification assembly; Battery Computer Assembly = controller (threshold triggered at full charge).
   • Docket activity through the retrieved record: Toyota answered and counterclaimed (Mar. 10, 2026); Bunker Hill replied to the counterclaim (Mar. 30, 2026); referral to the magistrate judge was vacated (April 29–30, 2026); scheduling conference set for June 2, 2026 before District Judge Robert W. Schroeder III.
   • Separately, Toyota filed IPR2026-00250 against US 10,549,648 (a different patent in the same family/portfolio), not against the '884. I found no IPR petition against the '884.

2. BUNKER HILL TECHNOLOGIES, LLC v. Nissan Motor Co., Ltd., No. 2:26-cv-00230 (E.D. Tex.), filed March 20, 2026. Asserted patents include 8,030,884 plus others (referenced as '023, '582, '439, '365, '121 and more). Accused products include 2023–25 Nissan Ariya, 2018–26 Nissan Leaf, and 2026 Nissan Rogue. Filing-fee receipt and docket entries are dated Mar. 20–25, 2026.

Google Patents itself flags this family under "Family has litigation" with E.D. Tex. cases 2:26-cv-00230 and 2:25-cv-01133, plus a Darts-IP "first worldwide family litigation" link.

5. Uncertainty / confidence notes

• High confidence on title, application number, filing/priority date, issue date, inventors, original assignee, claim count, claim text, and abstract — all taken from the Google Patents full text you supplied, which is authoritative for claim language.
• Moderate confidence on litany of current ownership: the Google Patents legal-events feed contains an internally inconsistent date ordering (a Feb. 20, 2025 Edison assignment appearing alongside later Mar. 26, 2025 Dolby/GE events), and I could not reach USPTO PatentCenter or the assignment database directly. The terminal owner is repeatedly stated as Bunker Hill Technologies, LLC.
• Moderate confidence on litigation specifics: they come from Stanford NPE/litigation databases, Justia dockets, RPX, and third-party complaint-analysis pages, not from PACER directly. The complaint-element mappings are third-party analyses, not court findings, and the analyses themselves flag likely disputes over whether a "Battery Computer Assembly"/"battery controller" performs the claim's specific compare-to-threshold step.
• No CAFC 2026 appeal located for the '884; stating that as a negative search result, not as a confirmed fact.
• The "adjusted expiration 2029-10-30" figure is the platform's assumption (2009 filing plus statutory term/adjustments), not a legal conclusion.

I'll search for litigation involving US 8,030,884 specifically.

Let me get more detail on each Bunker Hill case and confirm which patents were asserted.

Let me verify the Ford case and the second Nissan case, and check for any other assertions of the '884 patent.

PTAB / AIA Trial Review — U.S. Patent No. 8,030,884

Bottom line up front: I found no AIA trial proceeding of any kind against US 8,030,884. The structured "PTAB proceedings on file" block supplied in this prompt returns zero AIA trials from the USPTO Open Data Portal, and my independent web searches (PTAB decisions, litigation dockets, Unified Patents' challenge tracker, Docket Alarm/ipverse case databases) surfaced no IPR, PGR, or CBM naming the '884 patent. Because the ODP block is the canonical source and it is empty, the correct answer is zero proceedings — the analysis below is therefore mostly a negative finding plus the adjacent activity a defendant should not confuse with an attack on this patent.

Proceedings overview

Total AIA trial proceedings on US 8,030,884: 0 (0 active, 0 with claims invalidated, 0 with claims sustained, 0 settled, 0 institution denials). The patent has never been challenged at the PTAB, which means all 24 claims stand exactly as issued — claims 1–24 are UNTESTED, not "hardened." A defendant facing assertion cannot point to any FWD canceling anything, but also cannot claim the patent has been vetted: the absence of PTAB activity on a patent that is now being asserted by an NPE against Ford, Toyota, and Nissan is a vacuum, not a shield. Note: the prompt's ODP block is authoritative for AIA trials only; ex parte reexamination (a Central Reexamination Unit proceeding, not an AIA trial) is a separate track and is discussed below because a defensive aggregator is actively using it in this family's neighborhood.

Per-proceeding detail

None. There are no proceedings to detail. Rather than pad this section, here is the adjacent activity you must not mistake for an '884 proceeding:

IPR2026-00250 — Toyota Motor Corporation v. Bunker Hill Technologies, LLC

• Patent challenged: US 10,549,648 — NOT the '884 patent. (Title: "Propulsion System for Electric or Hybrid Electric Vehicles.")
• Type: Inter Partes Review
• Filed: 2026-02-03
• Status: Sources conflict — one case database reports "Terminated-Settled" (institution decision 2026-07-14, termination 2026-08-12); a docket aggregation snapshot taken earlier shows "Pending." I could not resolve the conflict and will not assert a disposition.
• Petition grounds: anticipation and obviousness of claims 1–20 over Conlon (US 2009/0176610 A1), Ortmann (US 2013/0012347 A1), and Reynolds (US 2014/0100726 A1), with a declaration by Dr. Mahdi Shahbakhti.
• Defensive value for '884: None directly. But it is the single most important pattern signal in this portfolio: Toyota is running a coordinated IPR campaign against the Bunker Hill/Dominion Harbor EV-charging family, and the '884 patent — asserted against Toyota in the same litigation — has so far escaped that campaign.
• Sources: https://sandbox.docketalarm.com/cases/PTAB/IPR2026-00250/Toyota_Motor_Corporation_v._BUNKER_HILL_TECHNOLOGIES_LLC/ and https://ipverse.greyb.com/ptab-web/cases/case-details/IPR2026-00250

IPR2026-00333 — Toyota Motor Corporation et al. v. Bunker Hill Technologies, LLC

• Patent challenged: US 11,374,508 — NOT the '884 patent. Toyota seeks cancellation of all 17 claims over Tsuzuki in combination with Reynolds, Imai, Ashtiani, Satoru, and Zing.
• Type: IPR | Filed: 2026 (per case-law aggregator)
• Defensive value for '884: Same pattern signal — Toyota is willing to file multiple IPRs per patent-owner in this family. It has not (as of my search) filed one on '884.
• Source: https://cases.arcticinvent.com/us/patent/us/petition-as-filed/ipr2026-00333/

Ex parte reexamination 90/016,093 — Unified Patents v. US 9,914,365 (Bunker Hill)

• Not an AIA trial, and not the '884 patent. On 2026-03-27 Unified Patents filed an ex parte reexamination request against US 9,914,365 (rapid-charging power electronics); the CRU granted it on 2026-06-01, finding substantial new questions of patentability on all challenged claims.
• Why it matters to an '884 defendant: it demonstrates the available validity-challenge routes against this owner — with IPRs unavailable or undesirable against an aging NPE patent, a third party (Unified, represented by Erise IP) used ex parte reexam instead. Unified is the defensive aggregator in this chain.
• Sources: https://www.unifiedpatents.com/insights/2026/3/29/dominion-harbor-entity-bunker-hill-ev-battery-patent-challenged and https://portal.unifiedpatents.com/exparte/90016093

Flagged but unverified: Unified's 2026-07-06 insight post ("Dominion Harbor entity Bunker Hill patent validity challenge coming soon") describes a Bunker Hill patent "generally relat[ing] to a vehicle-based uninterruptible power supply (UPS)" that Unified was then charting prior art against, and notes Bunker Hill has sued Ford, Toyota, and Nissan. That description does not match the '884 patent's disclosure well (the '884 spec is about onboard boost/buck charging of traction energy storage), so I cannot attribute it to '884. Treat it as a live risk that a further Bunker Hill patent may be challenged by Unified — verify the patent number before relying on it. Source: https://www.unifiedpatents.com/insights/2026/7/6/dominion-harbor-entity-bunker-hill-patent-validity-challenge-coming-soon

Strategic summary

Claim status. All 24 claims of US 8,030,884 — independent claims 1, 16, and 20, and dependents 2–15, 17–19, and 21–24 — are SUSTAINED in the sense of never having been adjudicated, and CANCELLED: none. There is no FWD, no certificate of cancellation, no adverse judgment, and no disclaimer I could find. Any validity argument against '884 today is built from scratch on § 102/§ 103 grounds in district court or in a fresh ex parte reexam; there is no PTAB record to borrow, quote, or estop anyone with. Note also the patent's term: priority 2009-08-31, statutory/PTA expiration recorded as 2029-10-30, which compresses the damages tail for any assertion campaign but also makes '884 an old patent — relevant because the PTO's current discretionary-denial and "settled expectations" policies (raised in the pending Supreme Court briefing by Unified) may make it harder to get an IPR instituted on a 2009 patent asserted late.

Estoppel landscape. There is no § 315(e)(2) estoppel on this patent, because no IPR/PGR was ever instituted. Practically, that cuts in favor of a defendant: the full universe of prior art — including patents, printed publications, and, in district court, system art, on-sale art, and § 112 grounds that IPR cannot reach — remains available. There is likewise no § 315(b) problem for the patent owner's current targets yet, but the clock is running: Bunker Hill's complaints are public, and service of a complaint starts the one-year § 315(b) window even if the case is later voluntarily dismissed (the Click-to-Call line of authority, with the PTAB's § 315(b) determinations being unreviewable under Thryv). As of today, 2026-09-30, the earliest-served defendants (Ford, complaint filed 2025-11-10 and terminated by joint dismissal 2026-02-11; Toyota, filed 2025-11-18) are approaching or near the end of that window — so a fresh IPR from those defendants on '884 is time-barred or nearly so. That is a strong reason the ex parte reexam route (as Unified used on '365) is the realistic vehicle for any new '884 challenge. (Caveat: I am reasoning from filing dates surfaced in search results, not from verified service dates; confirm service dates on the docket before treating any window as closed.)

Pattern signals. (1) No repeat-petitioner pattern on '884 — there is no petitioner at all. (2) Toyota is a serial petitioner against this owner (at least IPR2026-00250 on the '648 patent and IPR2026-00333 on the '508 patent), yet '884 was left unchallenged while the parallel litigation ran — possibly because the '884 claims are harder to map to prior art, possibly because of settlement timing. (3) A defensive aggregator is in the chain: Unified Patents is actively filing ex parte reexaminations against Bunker Hill/Dominion Harbor EV-charging patents (revealed in the '365 reexam grant, 2026-06-01) and has publicly signaled at least one more challenge. (4) Ownership is now NPE-style: the record shows General Electric → GE Intellectual Property Licensing → Dolby Intellectual Property Licensing → Edison Innovations → Bunker Hill Technologies, LLC (quitclaim, recorded 2026-04-09 per the Google Patents legal-events table; note the recorded dates in that table are not strictly chronological, so treat the exact sequence cautiously). Bunker Hill is characterized by Stanford's NPE database as a non-practicing entity. (5) Litigation venues: E.D. Tex., including Bunker Hill v. Toyota (2:25-cv-01133) and the case flagged in the prompt at 2:26-cv-00230; the '884 patent is among the asserted patents listed in the Bunker Hill E.D. Tex. complaints.
Sources: https://npe.law.stanford.edu/case/[308840](/patent/308840), https://patents.google.com/patent/[US8030884B2](/patent/US8030884B2)/en

Family risk that a defendant must not miss. The '884 patent has a continuation, US 8,487,582 (same title, filed 2011-05-02, claiming the 2009-08-31 priority date). A search-result listing of asserted patents in the Bunker Hill E.D. Tex. campaign includes '582 alongside '884. Invalidating or licensing around '884 does nothing to '582, which shares the same specification — any § 112 or priority analysis you develop against '884 generally transfers to '582, but you must challenge or clear it separately. There is also EP 2 290 778 B1, JP 6 068 778 B2, and CN 102005789 B for ex-U.S. exposure.

Recommended next steps

• Verify the negative finding directly, before relying on it. Run the patent number through the PTAB E2E / PTAB Center trial search for "8,030,884" and through USPTO Patent Center for any reexamination, reissue, disclaimer, or certificate of correction. The ODP ingest is the canonical AIA-trial list and it is empty for this patent; a manual E2E query is the cheapest way to confirm nothing was filed between the ODP snapshot and today (2026-09-30). Links: https://ptacts.uspto.gov/ptacts/ and https://patentcenter.uspto.gov/
• Do not build a defense on an FWD that does not exist. There is no PTAB disposition to quote or link. Any IPR-estoppel-based or "claims already canceled" argument about '884 is factually unavailable and would be sanction-bait.
• Treat the '884 validity case as a from-scratch prior-art project. Because there is no instituted IPR, you have no § 315(e)(2) estoppel exposure as a petitioner candidate only if you never file; conversely, the patent owner has not been forced to defend anything. The strongest near-term lever, given § 315(b) timing and the PTO's current institution climate, is likely an ex parte reexamination modeled on Unified's '365 request (90/016,093) — ex parte reexam is not subject to the § 315(b) bar and is not restricted to the petitioner's own litigation posture. For any client served inside the last 12 months, evaluate a protective IPR immediately: § 315(b) runs from service, not from dismissal, and Click-to-Call/Thryv mean you cannot count on the dismissal of a case to reopen the window.
• Watch the Toyota IPR campaign for spillover. Monitor IPR2026-00250 ('648) and IPR2026-00333 ('508) — if Toyota settles or the Board issues a merits decision in either, the prior-art packages and expert (Shahbakhti) may be reused against other family members, and the settlements may signal how Bunker Hill prices these patents.
• Track Unified Patents' next Bunker Hill filing. Unified has publicly stated a further challenge is coming against a Bunker Hill patent (described as vehicle-based UPS art), and it has shown it files ex parte reexams roughly two months before CRU grant. If your defense budget is limited, that filing may do work you would otherwise have to fund.
• Clear the continuation, not just '884. Confirm which claims of US 8,487,582 are being asserted; the '582 patent is the likeliest substitute if '884 claims are ever canceled or designed around.

Confidence statement. I have high confidence that no AIA trial proceeding exists against US 8,030,884 (ODP block empty + no contrary search result). I have lower confidence on: (a) the exact status of IPR2026-00250 (conflicting "pending" vs. "terminated-settled" reports, and in any event a different patent); (b) whether Unified's "vehicle-based UPS" target is or is not '884; and (c) current service dates driving the § 315(b) windows. I did not exhaustively query PTAB E2E or Patent Center (search-step limit reached), and I found nothing resembling a Federal Circuit appeal relating to this patent — consistent with there being no underlying PTAB decision to appeal.

I'll attempt to retrieve the underlying USPTO assignment records and correspondent data before reconstructing the chain.

I have solid litigation and chain-of-title context. Let me try to pin down reel/frame numbers and the recording correspondents.

Assignment Record Reconstruction — US Patent 8,030,884 B2

Data-integrity note up front. I could not reach USPTO PatentCenter / Assignment Center directly from this environment. The assignment facts below are drawn from (a) the Google Patents legal-events feed in the authoritative full text you supplied, (b) IAM, MarketScreener/S&P Capital IQ, Unified Patents, the Stanford NPE litigation database, and docket mirrors. Correspondent-of-record fields were not retrievable in any source I reached — I will not invent attorney names or reel/frame numbers to fill that field. Only two reel/frame numbers are actually sourced; the rest are listed without them and flagged.

(Also: the earlier summary flagged a "April 26, 2026" vs. September 30, 2026 date conflict. Your current prompt states 2026-09-30, which matches the fetch timestamp on the patent record, so that discrepancy appears resolved in favor of 2026-09-30.)

Inventors

Pattern check: Both inventors assigned to GE as employer, which is the normal course for GE Global Research salaried inventors — not a founder-held startup assignment. I found no evidence that either inventor departed GE within 12 months of filing, and no evidence of inventor-retained rights or later inventor-side transfers. The "inventors leave → portfolio fire-sale" precursor pattern is therefore not present. Note the fire-sale that did occur was driven by GE corporate divestiture (see below), a decade later and unrelated to inventor turnover.

Original assignee

General Electric Company (New York), recorded 2009-08-31 at reel 023169/0396.

• Line of business: diversified industrial/technology conglomerate (power, aviation, healthcare, and at the time a substantial transportation/EV-drive business). The patent itself is an EV/plug-in traction-drive charging invention — squarely within GE's then-active hybrid/electric drive and locomotive electrification work.
• Product embodiment: GE was an operating company in this space and its engineers did build and deploy hybrid-drive and traction power-electronics systems (e.g., hybrid locomotive and heavy-vehicle drive programs). I cannot confirm that GE ever shipped a commercial product practicing the two-stage claim-20 charging method, and I will not assert that it did.
• Current status (as assignor): GE did not file for bankruptcy. What happened is a corporate restructuring/divestiture: GE spun into GE Aerospace and GE Vernova, and the GE Licensing patent portfolio (reportedly ~5,000 patents, ~$429M) was sold to Dolby Laboratories (NYSE: DLB) in September 2024. GE's patent-holding arm appears in the chain as GE Intellectual Property Licensing, LLC. This is a divestiture/monetization, not a Chapter 7/11 fire-sale.

Assignment timeline

Source reel/frame are given only where actually observed. Non-assignment legal events (maintenance fees, grant) are shown for completeness and clearly labeled.

• 2009-08-28 / 2009-08-29 (executed) / recorded 2009-08-31 — Reel 023169/0396

  • Conveyance: Assignment (ASSIGNMENT OF ASSIGNORS INTEREST)
  • Assignor: Robert Dean King; Robert Louis Steigerwald (individually)
  • Assignee: General Electric Company, New York
  • Correspondent: not retrievable from the sources available — no correspondent data in the Google Patents feed; I will not guess.
  • Context: Original employer assignment at filing.

• 2011-09-14 — not an assignment — status event: patent grant ("PATENTED CASE"). No reassignment of title.

• 2015-04-06 / 2019-03-25 / 2023-03-22 — not assignments — maintenance-fee payments (4th, 8th, 12th year, large entity). These confirm the patent stayed alive and fee-paying but transfer no title.

• (date not established) General Electric Company → GE Intellectual Property Licensing, LLC

  • Conveyance: Assignment (ASSIGNMENT OF ASSIGNOR'S INTEREST, per the Google Patents event text)
  • Reel/frame: not retrieved (Google's feed shows this event dated 2025-03-26, but see inconsistency note below)
  • Correspondent: not retrievable.
  • Context: Internal corporate restructuring of GE's patent holdings into its licensing subsidiary.

• (date not established) GE Intellectual Property Licensing, LLC → Dolby Intellectual Property Licensing, LLC

  • Conveyance: Change of Name (CHANGE OF NAME — assignor GE IP Licensing LLC)
  • Reel/frame: not retrieved
  • Correspondent: not retrievable.
  • Context: Change of name only, tied to Dolby's September 2024 acquisition of the GE Licensing portfolio. (Google's feed timestamps this 2025-03-26; the underlying Dolby/GE deal closed September 2024 — inconsistency flagged below.)

• 2025-02-19 (executed) / recorded 2025-02-20 — Reel 070293/0273

  • Conveyance: Assignment (ASSIGNMENT OF ASSIGNOR'S INTEREST)
  • Assignor: Dolby Intellectual Property Licensing, LLC
  • Assignee: Edison Innovations, LLC, Texas
  • Correspondent: not retrievable from the sources I reached.
  • Context: Transfer-to-asserter / bulk portfolio sale. Dolby sold ~2,500 of the assets it had acquired from GE Licensing to Edison Innovations, a subsidiary of Dominion Harbor Group (announced 2025-02-19; legal advisor to Dolby on the GE Licensing deal was Wilson Sonsini). Edison Innovations = licensing-only entity; it announced "immediate rollout of licensing opportunities."

• 2026-04-09 (recorded) — no reel/frame retrieved

  • Conveyance: Quitclaim Assignment
  • Assignor: Edison Innovations, LLC
  • Assignee: Bunker Hill Technologies, LLC
  • Correspondent: not retrievable.
  • Context: Intra-family reorganization / transfer-to-asserter. Bunker Hill Technologies is itself a Dominion Harbor Enterprises, LLC entity (confirmed by Unified Patents' write-up of Bunker Hill's campaign). So Edison Innovations → Bunker Hill is a same-principal transfer within the Dominion Harbor stable, not an arm's-length sale. Flagged anomaly: Bunker Hill is named as plaintiff in suits filed Nov. 2025, i.e., before this April 2026 quitclaim recordation — title was papered late or through an unretrieved intermediate.

Assignment Center caveat: The two reel/frame numbers above (023169/0396 and 070293/0273) are the only ones I could ground. The GE→GE IP Licensing, GE IP Licensing→Dolby (name change), and Edison→Bunker Hill links exist as recorded events but I could not retrieve their reel/frame or correspondent fields. Verify all three directly at the USPTO Assignment Center.

Inconsistency to flag: Google Patents lists the Edison Innovations acquisition event on 2025-02-20 while listing the preceding GE→GE IP Licensing and GE IP Licensing→Dolby events on 2025-03-26 — i.e., the feed shows the downstream transfer dated before its upstream predecessors. That ordering cannot be literally correct. The press-record sequence is: GE Licensing → Dolby (Sept. 2024) → Edison Innovations (Feb. 19, 2025). Treat the Google feed dates for the GE IP Licensing and Dolby name-change steps as unreliable.

Timeline diagram

timeline
    title Ownership of US 8030884
    2009 : Filed by General Electric
         : Inventors assign rights to GE
    2011 : Patent issued
    2024 : GE Licensing sold to Dolby
    2025 : Dolby sells assets to Edison Innovations
         : Edison is a Dominion Harbor entity
         : Suits filed vs Ford and Toyota
    2026 : Quitclaim to Bunker Hill Technologies
         : Suit filed vs Nissan
         : Unified reexam targets sibling patent

NPE / troll-pattern signals

1. Shell-entity transfer — PRESENT.
The patent left an operating company and passed into a licensing-only chain: GE → GE Intellectual Property Licensing, LLC → Dolby Intellectual Property Licensing, LLC (reel-less name change) → Edison Innovations, LLC (reel 070293/0273, recorded 2025-02-20) → Bunker Hill Technologies, LLC (quitclaim, recorded 2026-04-09). Edison Innovations "Innovations" and Bunker Hill "Technologies" are licensing/assertion nameplates, and Edison Innovations was publicly described as a Dominion Harbor Group licensing subsidiary with no products. Concrete evidence beyond the name: the Feb. 19, 2025 acquisition announcement frames the assets as a licensing portfolio ("immediate rollout of licensing opportunities"), and the entity is a Dominion Harbor subsidiary, not an operating manufacturer.

2. Known asserter in the chain — PRESENT.
Neither Edison Innovations nor Bunker Hill is on your enumerated list (Acacia, Marathon, IV, Wi-LAN, Conversant, etc.), but both are Dominion Harbor entities — Dominion Harbor Group / Dominion Harbor Enterprises — a well-known high-frequency patent licensing/assertion organization. Grounding: the Edison Innovations press release describing it as "a subsidiary of global patent licensor Dominion Harbor Group" (Feb. 19, 2025), and Unified Patents' March 27, 2026 write-up describing "Bunker Hill Technologies, an NPE and entity of Dominion Harbor Enterprises, LLC." Stanford's NPE litigation database classifies Bunker Hill as a Non-Practicing Entity across its dockets.

3. Repeat correspondent across the chain — UNVERIFIABLE / not established.
I could not retrieve a correspondent of record for any recording in this chain, so I cannot confirm or refute a recurring recording attorney, and I will not name one. Separately, on the litigation side (not the assignment side), there is a clear repeat player: Patrick Joseph Conroy of Nelson Bumgardner Conroy PC (Dallas) is counsel of record for Bunker Hill on the Ford (2:25-cv-01116), Toyota (2:25-cv-01133), and Nissan (2:26-cv-00230/00231) complaints. That is litigation counsel recurrence, not assignment-correspondent recurrence — the signal as you defined it stays unclear/not established.

4. Cascading transfers — PRESENT.
GE → GE IP Licensing → Dolby IP Licensing → Edison Innovations → Bunker Hill Technologies is a chain of four transfers, three of them within roughly 18–20 months (Sept. 2024 through 2026), with the final two hops (Dolby → Edison, Feb. 2025; Edison → Bunker Hill, 2026) landing the patent in the same corporate family (Dominion Harbor). The final hop is an intra-family quitclaim — precisely the "chained LLCs, same principals" pattern.

5. Pre-litigation transfer — PRESENT (with a documented wrinkle).
Edison Innovations acquired the portfolio Feb. 19, 2025; the first suits naming this patent followed within ~9 months — Ford, 2:25-cv-01116 (Nov. 10, 2025) and Toyota, 2:25-cv-01133 (Nov. 18, 2025) — and Nissan, 2:26-cv-00230 (Mar. 20, 2026). The transfer-to-asserter timing fits the signal. The wrinkle: the Edison → Bunker Hill quitclaim was not recorded until Apr. 9, 2026, yet Bunker Hill was already the named plaintiff in Nov. 2025 — i.e., assertion preceded the recorded transfer here. That inversion is itself a red flag for a late-papered or unretrieved intermediate assignment.

6. Bankruptcy fire-sale — NOT PRESENT.
GE did not enter Chapter 7/11. The relevant event is a solvent divestiture: the GE Licensing portfolio (≈5,000 patents, ≈$429M) was sold to Dolby in Sept. 2024, which then resold ~2,500 assets to Edison Innovations. No court-supervised sale, no distressed debtor. Distinguished from Kodak/Nortel/Polaroid fact patterns.

7. Privateering — NOT PRESENT / UNSUPPORTED.
There is no evidence GE (or Dolby) retained an interest in, funded, or directs this assertion campaign against Toyota, Ford, and Nissan. The record shows an outright sale of assets and an independent Dominion Harbor monetization program. "Aggregator bought a portfolio and monetized it" is distinct from "operating company using an NPE proxy against competitors"; the latter element is absent.

8. Defensive aggregator — NOT PRESENT.
The chain terminates at Bunker Hill Technologies, LLC, an asserting NPE — the opposite of neutralization. Reinforcing that the patent is live as an assertion tool: Unified Patents filed an ex parte reexamination on March 27, 2026 against sibling US 9,914,365 (same Bunker Hill campaign; asserted against Ford, Toyota, and Nissan), and Toyota filed IPR2026-00250 against US 10,549,648, another family/portfolio patent. Those are third-party validity challenges against the campaign — not title transfers, and not a defensive acquisition.

Verdict

NPE — high confidence.

The chain is grounded in recorded USPTO events, not naming inference: reel 023169/0396 (GE, 2009-08-31) → GE Intellectual Property Licensing, LLC → Dolby Intellectual Property Licensing, LLC (name change) → reel 070293/0273 (Edison Innovations, LLC, recorded 2025-02-20) → Bunker Hill Technologies, LLC (quitclaim, recorded 2026-04-09). That gives the four strongest signals simultaneously: a shell-entity transfer out of an operating company into licensing-only LLCs, a known asserter (both Edison Innovations and Bunker Hill are Dominion Harbor entities), cascading transfers within ~18 months, and a pre-litigation transfer immediately preceding the Nov. 2025 Ford/Toyota suits and the Mar. 2026 Nissan suit (with the anomaly that Bunker Hill was suing months before the quitclaim was recorded). Corroboration: Stanford's NPE database labels Bunker Hill a non-practicing entity, and Unified Patents ran an ex parte reexam against a sibling patent in the same campaign on 2026-03-27. Caveat driving the "moderate" vs "high" tension: because I could not retrieve the correspondent-of-record for any link, the recurring-recording-attorney signal is unverified — the high-confidence call rests on the other signals, which are independently sufficient (2+ strong signals).

Verify directly:

• USPTO Assignment Center — https://assignmentcenter.uspto.gov/ (search patent 8,030,884)
• USPTO legacy assignment search — https://assignment.uspto.gov/patent/index.html#/patent/search?q=8030884
• Google Patents legal events — https://patents.google.com/patent/[US8030884B2](/patent/US8030884B2)/en

Reel/frame still to retrieve (do not treat as absent — treat as unretrieved): the GE→GE IP Licensing, GE IP Licensing→Dolby name-change, and Edison Innovations→Bunker Hill Technologies recordings.

I'll research each cited reference. Let me start with searches to ground the prior-art records.

Let me research the remaining cited references.

Prior-Art Analysis — US 8,030,884 B2

Scope note up front: I was working against a limited search budget and was cut off before I could pull the full spec text of every one of the eleven references. What follows separates (a) what is verifiable from the authoritative record (the patent's own citation table, plus the full-text snippets I retrieved for several references) from (b) my lower-confidence characterizations of the remaining references. I flag every instance where I am inferring rather than quoting.

1. Which "citation" set applies

The Google Patents record for US 8,030,884 B2 contains three distinct citation lists, and conflating them is a common error:

Your question — "look at each patent citation for 8030884" — maps to the 11-reference front-page list. I analyze those below and treat the 26 family-cited references separately in §4, because several of them are, candidly, more on-point to the two-stage charging concept than some of the 11.

2. The eleven examiner-cited references

2.1 US 5,373,195 — Technique for decoupling the energy storage system voltage from the DC link voltage in AC electric drive systems

• Dates: filed 1992-12-23; issued 1994-12-13. Assignee: General Electric. Inventors: Rik W. A. A. De Doncker; Robert D. King. (Verified — Espacenet bibliographic record and Google Patents.)
• Disclosure: An AC electric drive with a bi-directional power semiconductor interface — a buck-boost (bi-directional) DC-DC converter — between the battery/auxiliary storage device and the inverter, "boosting an input dc voltage and … decoupling the dc link voltage from the input dc voltage." Control means (30/40) receive dc-link voltage, battery voltage, and dc input current measurements and regulate along a torque envelope. Confirmed verbatim in the retrieved text: switching devices T_b1/T_b2 with antiparallel diodes, filter inductor L_f, and closed-loop current/voltage sensors.
• Anticipation assessment: This is the closest structural reference to the bi-directional voltage modification assembly element of claim 1 and to dependent claims 7/13/18/23 (bi-directional DC-DC converter that bucks/boosts). But it contains no external/high-impedance charging source, no "charge bus … coupleable" to such a source, and no two-stage threshold-triggered hand-off. Therefore it does not anticipate claim 1, 16, or 20, and cannot anticipate the dependents (which incorporate the parent's limitations). Relevance is §103 — it supplies the bi-directional converter element.

2.2 US 5,589,743 — Integrated cranking inverter and boost converter for a series hybrid drive system

• Dates: filed 1995-03-03; issued 1996-12-31. Assignee: General Electric. Inventor: Robert D. King. (Verified — patent PDF front page.)
• Disclosure: A three-phase inverter placed substantially in parallel with a full-bridge rectifier in a series hybrid, doing double duty as cranking inverter and boost converter; the boost converter raises the DC-link voltage above what an uncontrolled rectifier can produce. Anti-parallel diodes form an uncontrolled rectifier when the active devices are off. Current sensors (30/32, 38/40) provide overcurrent control.
• Anticipation assessment: Relevant to the "reuse of traction inverter as a boost converter," "plurality of diodes," and "boost" concepts (claims 2, 4, 5, 17, 22). It is a series-hybrid internal architecture — the source is an engine-driven alternator, not an external high-impedance source coupleable to a charge bus, and there is no compare-to-threshold → switch-stages logic. No anticipation; §103 reference for the boost-converter use of the inverter.

2.3 US 5,903,449 — Bi-directional power control system for voltage converter

• Dates: filed 1998-06-09; issued 1999-05-11. Assignee: General Electric. (Dates verified from the patent's citation table.)
• Disclosure: Lower confidence. Title and GE lineage indicate a bi-directional control scheme for a voltage converter (a foundational GE DC/DC control patent). I did not retrieve its full text within budget.
• Anticipation assessment: On its face it addresses bi-directional converter control, relevant as §103 support to the "control … to modify one of a voltage and a current" element. No indication it discloses an external high-impedance charging source or threshold-based charging. No anticipation — §103.

2.4–2.6 US 6,331,365 / 6,737,822 / 7,049,792 — GE Traction motor drive family (all filed 1998-11-12)

• Dates: all share filing 1998-11-12; issued respectively 2001-12-18, 2004-05-18, 2006-05-23. Assignee: General Electric. (Verified.)
• Disclosure (from retrieved US 6,331,365 text): A hybrid battery system combining a high-power-density battery (e.g., Ni-Cd, coupled across the DC link) with a high-energy-density battery (e.g., zinc-air, coupled through a boost converter with a blocking diode), plus a dynamic retarder and AC motor drive. A hybrid power source controller uses current and voltage sensors for closed-loop control; the boost converter regulates how much energy is drawn from the high-energy battery, and regenerative energy is captured in the high-power battery.
• Anticipation assessment: This is the most substantive of the GE citations for the multi-storage-device aspects — relevant to claims 10, 11, 12 (a "high power" device alongside a "low power" device; simultaneous charge control) and claim 2's "instantaneous acceptance capability." The '884 spec's own "first/second energy storage device" (12/100) and bi-directional DC-DC converter (102–106) language tracks this family's disclosure closely, and the '884 shares inventor King with these references — a fact worth noting for derivation/§103 analysis. However, again, no external high-impedance source, no charge bus coupleable to it, no two-stage threshold hand-off. No anticipation; strong §103 candidates.

2.7 US 2002/0051368 A1 — Mobile power generation system (Ulinski)

• Dates: filed 2000-02-14; published 2002-05-02. (Verified from citation table.)
• Disclosure: Lower confidence — a mobile power-generation system. Pertinent, if at all, only to the generic "power electronics + controller" environment.
• Anticipation assessment: No anticipation. I see no basis for it to disclose the charge-bus/high-impedance-source two-stage charging. Treat as background/§103 only with caution.

2.8 US 7,499,296 B2 — Electric power converter device with control means and process and converting power (MGE UPS Systems)

• Dates: filed 2004-09-27; issued 2009-03-03. (Verified.) Assignee: MGE UPS Systems.
• Disclosure: Lower confidence — a power-converter control apparatus. Presumably a DC/DC or DC/AC converter with control means; it is an uninterruptible-power-supply context.
• Anticipation assessment: No anticipation of the vehicle charging claims. Its only plausible role is generic §103 support for "controller … control … voltage converter."

2.9 US 2007/0012492 A1 — Power generation system suitable for hybrid electric vehicles (Duo Deng)

• Dates: filed 2005-06-22; published 2007-01-18. (Verified.)
• Disclosure: Lower confidence — a hybrid-EV power-generation system. Relevant, at most, to the hybrid-EV environment common to the '884.
• Anticipation assessment: No anticipation. Background/§103 only.

2.10 US 7,750,501 B2 — System and method of over voltage control for a power system (Continental Automotive Systems US)

• Dates: filed 2005-10-27; issued 2010-07-06. (Verified.) Assignee: Continental Automotive Systems US, Inc.
• Statutory note: Because it was filed 2005-10-27 (before the '884's 2009-08-31 filing) but issued 2010-07-06 (after), it is prior art only under the pre-AIA §102(e) branch (US patent/publication effective as of its filing date), or via an earlier application publication — not §102(b).
• Disclosure: Lower confidence — over-voltage control for a vehicle power system, i.e., a controller comparing a monitored voltage to a limit. This is the citation most suggestive of the "compare … with a threshold value" element.
• Anticipation assessment: Even assuming it discloses threshold-based voltage limiting, it is an internal vehicle power-system context, not "charging energy supplied from a high-impedance voltage source to a first energy storage device," and it lacks the stage hand-off. No anticipation; §103 for the threshold-comparison element (relevant to claims 6, 12, 19's threshold options).

2.11 US 7,595,597 B2 — Vehicle propulsion system (GE)

• Dates: filed 2006-01-18; issued 2009-09-29 (pre-grant pub. US 2007/0164693 A1, 2007-07-19). Assignee: General Electric.
• Statutory note: issued 2009-09-29, after the '884's 2009-08-31 filing, so §102(e) (filing-date-effective) rather than §102(b); its 2007 publication is §102(a)/(b)-relevant for some claims.
• Disclosure: Moderate confidence — a GE vehicle propulsion system of the same genre as the '884 (bi-directional voltage modification / energy storage / traction inverter). From the retrieved Espacenet and citation data it is a propulsion-system reference in the same pipeline as the '884.
• Anticipation assessment: Same gap as the others — internal propulsion architecture, no external plug-in high-impedance charging source coupleable to a charge bus, no two-stage threshold control. No anticipation; §103.

3. Bottom-line §102 conclusion

None of the eleven cited references anticipates any claim of US 8,030,884. Anticipation under 35 U.S.C. §102 requires that a single reference disclose every element of the claim as arranged. No cited reference discloses the combination that defines all three independents:

1. a charge bus (or second voltage bus) coupleable to an external high-impedance voltage source;
2. charging energy delivered from that source into the energy storage device; and
3. a controller that compares the monitored transfer to a threshold and only after the threshold is crossed hands off to active converter control to modify voltage/current (or buck/boost).

The cited art is overwhelmingly internal-vehicle propulsion/battery-management art. The genuinely novel move in the '884 — using the traction electronics as an external-source charger with an impedance-limited first stage and a controlled second stage — is absent from all eleven. These are properly framed as §103 obviousness references, not §102 anticipation references. Two of them (US 6,331,365 and US 5,373,195) are the strongest, and the shared inventorship (King) with the '884 spec's first/second-storage-device and bi-directional-converter architecture should be noted.

Dependent-claim note: because dependent claims incorporate all limitations of the claim from which they depend, a reference that fails to anticipate independent claim 1/16/20 cannot anticipate any of their dependents either, regardless of how well it matches the dependent's added limitation.

4. Family-cited references worth flagging (different list — cited against the EP/JP counterparts)

I inspected the "Family Cites Families (26)" list because it contains references the EP examiner treated as closer than the U.S. set. Of these, the following are potentially more germane to the two-stage charging idea, though I did not retrieve full text and cannot confirm their disclosure (flagging as low confidence):

• US 6,118,678 A (Limpaecher, 1999-06-10 → 2000-09-12) — "Charge transfer apparatus and method therefore." A charge-transfer topology; worth retrieving.
• JP S59-61402 A (Toshiba, 1982-09-30 → 1984-04-07) — "Charger for battery driven vehicle." A very early on-board-charger reference.
• US 5,132,604 A (Honda, 1989-04-04 → 1992-07-21) — "Engine starter and electric generator system."
• WO 2009/022638 A1 and US 2007/029986 A1 — these appear in the EP 2 290 778 B1 search report as "relevant technical background" (verified in the retrieved EP B1 specification, ¶[0004]). They postdate several of the 11 and are the EP examiner's own background citations.
• Assorted JP/KR on-board charger art: JPH06-178407, JPH01-076608, JP3477850, JP3277825, JP4337442, JP4367391, KR100999969, KR100848297.

5. Most-relevant ranking (for §103 charting)

1. US 5,373,195 — bi-directional buck-boost interface between storage and DC link (claims 1, 7, 13, 18, 23).
2. US 6,331,365 (+ 6,737,822, 7,049,792) — hybrid high-power/high-energy storage + boost converter + current/voltage-sensed controller (claims 2, 10, 11, 12).
3. US 7,750,501 — voltage-over-limit control (threshold-comparison element; claims 6, 12, 19).
4. US 5,589,743 — traction inverter doubling as boost converter with diode rectification (claims 2, 4, 5, 17, 22).
5. US 7,595,597 — same-genre GE propulsion system (general §103 backdrop).
   6–11. 5,903,449; 7,499,296; 2002/0051368; 2007/0012492 — generic converter/controller/power-system art (weak).

6. Conflicts / corrections to prior sections and confidence

• No contradiction with the previously generated summary or litigation summary on the bibliographic or claim data; the 11-reference citation list here reconciles exactly with the "Cited prior art (9 refs)" partial list in the earlier summary (which named only 9). The full front-page table lists 11 — the earlier summary's "9" appears to have tracked Google's partial "Citations (9)" block, which omits US 6,737,822 and US 7,049,792 even though both appear in the full "(56) References Cited" table. Treat 11 as the correct count of examiner-cited U.S. references.
• High confidence on all citation titles, inventors, assignees, and filing/issue dates — these are from the patent's own (56) table and corroborated by Espacenet/Google Patents records I retrieved.
• High confidence on the §102 conclusion (no anticipation) — it follows from the independent-claim limitations versus the retrieved disclosures.
• Moderate/low confidence on the substance of US 5,903,449, US 7,499,296, US 2002/0051368, US 2007/0012492, and US 7,750,501 — I characterize these from title/known context, not full-text verification, because I exhausted my retrieval budget. If you want per-reference element-by-element §103 charts, those five need a full-text pull.
• Date caveat (verbatim, carried forward): the task states the current date as April 26, 2026, while the fetched patent/docket records carry timestamps of September 30, 2026. I am reporting records as returned rather than "correcting" either date.
• Statutory note: US 7,595,597 (issued 2009-09-29) and US 7,750,501 (issued 2010-07-06) post-date the '884's 2009-08-31 filing and are therefore §102(e)-effective (filing-date) references, not §102(b) references; I have not treated them as §102(b) art.

Grounding URLs:

• US 8,030,884 (citation table, claims, spec): https://patents.google.com/patent/[US8030884B2](/patent/US8030884B2)/en
• US 5,373,195: https://patents.google.com/patent/[US5373195A](/patent/US5373195A)/en and https://worldwide.espacenet.com/publicationDetails/biblio?CC=US&NR=[5373195A](/patent/5373195A)
• US 6,331,365: https://patents.google.com/patent/[US6331365B1](/patent/US6331365B1)/en
• US 5,589,743: https://patents.google.com/patent/US5589743
• EP 2 290 778 B1 (family search-report background): https://patentimages.storage.googleapis.com/78/29/53/71eb64773475c5/EP2290778B1.pdf

I'll ground this analysis by verifying the key references from the Prior Art section before building the obviousness combinations.

Useful confirmations. Let me verify the remaining key references from the citation list.

Obviousness Analysis — US 8,030,884 B2 under 35 U.S.C. § 103

Note on cross-referencing: This builds on the previously-generated Patent summary and Litigation summary. One flagged inconsistency carries forward: the prompt states today is April 26, 2026, while the Google Patents record you supplied carries fetch/legal-event timestamps into September 30, 2026. I use the record as returned and do not "correct" it. Also, per the earlier summary's §5, the intermediate chain-of-title dates are internally inconsistent; none of that affects the §103 analysis.

Governing law: The application was filed August 31, 2009, so pre-AIA § 103 applies (Graham v. John Deere; KSR Int'l v. Teleflex). Because the effective filing date predates March 16, 2013, references that issued after the filing date but were filed earlier (e.g., US 7,750,501, filed Oct. 27, 2005; US 7,595,597, filed Jan. 18, 2006) still qualify as prior art under pre-AIA § 102(e).

Level of ordinary skill (PHOSITA): a B.S. in electrical engineering plus ~2–5 years in power-electronics/motor-drive design for traction or industrial drives, or equivalent — familiar with three-phase inverters, bidirectional DC-DC converters, PWM control loops, and transformer-isolated charging.

1. The prior art of record (the "Prior Art" section)

These are the examiner-cited references listed on the patent page, plus the family-citation list. I have verified the text/abstracts of the ones marked ✅; the remainder I characterize only from their titles in the citation list and flag as unverified (⚠).

I could not retrieve full text for the ⚠ items before exhausting my search budget; where I rely on them I say so explicitly. The core grounds below rest on the ✅ references, which I did verify.

2. Claim 1 — element mapping

Ground 1 (primary): Claim 1 is obvious over US 5,373,195 in view of JP H06-178407, further in view of US 7,750,501.

• US 5,373,195 supplies the bidirectional voltage-modification assembly, the DC link, the sensors and controller, and — most importantly — the two-stage behavior: (i) passive transfer through a forward-biased diode with the switches off, then (ii) active boosting once the switches are enabled. That is precisely the '884's Stage 1 (diode conduction, impedance-limited) → Stage 2 (active converter control).
• JP H06-178407 supplies the missing element of an external source coupled into the traction inverter/charge bus, and does so expressly for the '884's stated purpose — eliminating dedicated on-board charger hardware to cut EV weight and cost. Its control circuit (10) already performs two-mode control (drive vs. charge).
• US 7,750,501 supplies the threshold comparison expressio: detect bus voltage, compare to a threshold, then command the converter.

Motivation to combine (KSR rationales):

1. Express problem statement + express solution. The '884's own Background concedes that "dedicated components such as boost converters, high-frequency filters, choppers, inductors… add extra cost and weight." JP H06-178407 states the identical objective in its 効果 and achieves it by the identical means. That is not hindsight — it is the asserted invention's own premise, articulated in a printed publication 15 years earlier.
2. Same field, same problem, same architecture. US 5,373,195, US 6,331,365, US 7,595,597 and the '884 share a common assignee lineage (GE) and a common hardware topology (battery ↔ DC-DC ↔ DC link ↔ inverter ↔ AC machine). A PHOSITA designing a plug-in variant would start from this exact family.
3. Predictable result / known technique. Routing current through freewheel/anti-parallel diodes during the high-current phase and closing an active loop afterwards is the standard, predictable behavior of every voltage-source inverter and bidirectional buck-boost (US 5,373,195, col. describing forward-biased diode Db1).
4. Threshold-triggered hand-off is a design choice. US 7,750,501 already teaches "compare a detected bus voltage to a threshold, then act on the converter," with a hysteresis comparator; applying that known control to the charging hand-off is the mere substitution of a known element to obtain a predictable result.

3. Claim 16 (method) and Claim 20 (system)

Claim 16 tracks claim 1 with "first voltage bus"/"second voltage bus" nomenclature. Same ground: US 5,373,195 + JP H06-178407 + US 7,750,501, with the "second voltage bus" reading on the DC link / inverter DC terminals to which the external source is coupled. JP H06-178407 additionally shows the coupling steps (switch 4 switching the plug cord/reactor into the inverter).

Claim 20 (the claim asserted in the E.D. Tex. cases per the Litigation summary) narrows the threshold to "one of a voltage of the energy storage device and an average rectified line voltage of the charge bus."

• "Voltage of the energy storage device": US 5,373,195 (voltage sensor 42 monitoring battery voltage); US 5,903,449 (voltage-limiting system operating on a measured voltage); US 7,750,501 (bus voltage vs. threshold voltage).
• "Average rectified line voltage of the charge bus": the average of a rectified AC line is a standard, well-known quantity in any AC-fed DC bus; US 5,903,449's multi-phase bus regulation and US 5,373,195's inverter with anti-parallel diodes D1–D6 (which rectify motor-side AC) supply it.

Ground 2: Claim 20 obvious over US 5,373,195 + JP H06-178407 + US 7,750,501, optionally + US 5,903,449.

4. Dependent claims

5. Where the patent is most likely to survive — and the honest weaknesses in the art

1. Claim 4 (same-phase boost operation). The '884 frames operating the paired half-phase modules at the same phase to "reduce or eliminate high-frequency torque ripple in motor 40." JP H06-178407 avoids motor excitation during charging by mechanically decoupling the motor (double-throw switch), i.e., it teaches away from leaving the machine connected. An examiner would likely need a secondary reference disclosing common-mode/interleaved operation of paralleled converters for torque cancellation. This is the limitation I would expect to be pressed in an IPR — and the one most exposed if the patentee cannot show a specific, non-routine implementation.

2. "High-impedance voltage source" as a claim element in claim 1. Claim 1 recites the source as part of the apparatus, whereas claim 20 recites only "a charge bus configured to receive charging energy from a voltage source." If "high-impedance" is construed to require a specific impedance magnitude or a source incapable of fast current control, claim 1's scope narrows and JP H06-178407's reactor-based source becomes a closer, cleaner fit. If construed as a purely functional/relative term ("impedance-limited relative to the storage device's acceptance capability"), claim 1 is broad and correspondingly more exposed.

3. The "instantaneous acceptance capability larger than instantaneous delivery capability" limitations (claims 2, 7, 13). These are functional relative-capability recitations. Under KSR, arranging known batteries and known sources so that one's acceptance exceeds the other's delivery is a predictable design parameter, not a patentable distinction — but the patentee will argue it is the reason the two-stage scheme works (Stage 1 is inherently impedance-limited), and the prior art of record does not, on the faces I verified, state that specific inequality.

4. No single reference anticipates. On the verified text, none of the §102 references discloses all of claim 1. The case is therefore a §103 case built on (a) a GE traction-drive primary, (b) JP H06-178407 for the external-source-into-the-inverter coupling, and (c) a threshold-comparison reference. That is a three-reference combination, which invites a "motivation to combine" fight and increases the risk of hindsight challenge.

5. Secondary-consideration exposure. The '884 has a real commercial story (it is being asserted against Toyota and Nissan, per the Litigation summary), and rapid-charging capability is a recognized need. Expect the patentee to argue unexpected results in the interaction of Stage-1 diode conduction with Stage-2 boost. Whether that succeeds turns on whether the record shows a comparative advantage over JP H06-178407's single-stage charging — which the specification, as quoted, does not establish with data.

6. Bottom line

• Claims 1, 16, 20 (and the asserted claim 20 in particular) are, in my assessment, likely obvious over US 5,373,195 + JP H06-178407 + US 7,750,501, with US 5,903,449 and US 6,331,365 as reinforcing secondary references. The combination supplies every element, and the motivation is supplied by the references themselves (JP H06-178407's express weight/cost-reduction rationale) and by the '884's own admitted prior art.
• Claims 2–3, 5–15, 17, 18–24 are likely obvious over the same grounds plus US 6,331,365 (dual-battery / boost-buck, simultaneous charging) and US 5,373,195 (diode-then-active two-stage).
• Claim 4 is the strongest candidate for survival absent additional art.
• Confidence caveat: I verified the text of US 5,373,195, US 5,903,449, US 6,331,365, US 7,750,501 and JP H06-178407. I did not retrieve US 5,589,743, US 6,737,822, US 7,049,792, US 7,595,597, US 7,499,296, US 2002/0051368, US 2007/0012492, or the Japanese family-cites; anything in §4 resting on those is inferred from title/spec-field alone and should be confirmed before being relied on in a petition. No IPR against the '884 was located in the earlier search, so this analysis is prospective rather than a prediction of filed grounds.