US 11215159

I'll search for authoritative information on this patent number, including any litigation/docket activity.

Let me check for any litigation or CAFC docket activity involving this patent.

US Pat. No. 11,215,159 — Verification Summary

Scope/caveat: I could not query the USPTO PatentCenter/PAIR backend or the CAFC docket system directly; the results below are drawn from the Google Patents full text, Justia Patents, and the EPO register (EP3781806B1, same family). I found no CAFC (or district court) litigation, appeal, or IPR activity associated with this patent number in the 2025–2026 material available to me. Treat that negative litigation finding as provisional rather than authoritative.

Bibliographic data (per the front page)

Abstract (patent's own wording)

A kinetic modular machine for producing electricity from flows, either mono- or bi-directional, moving at different speeds, comprising one or more "open center" coaxial turbines; a floating/positioning system; and a connection between the machine and a docking. Each turbine has a rotor, a stator, and a synchronous generator. In multiple-turbine configurations the turbines are structurally, mechanically and electrically independent. The floating/positioning system comprises a floater, a wing, and a fixture linking the turbines to the floater, implementing control of the rotational axes (roll, pitch, yaw), with the wing keeping the machine at a given distance from the shore and fluid surface. The modular design allows flexible design and low installation/maintenance costs.

Independent claim — plain-language overview

Claim 1 is the sole independent claim. It recites a modular kinetic machine (M) for generating electricity from fluid flows, characterized as:

• Adapted to be floating in a fluid, "open center" (no central shaft/hub), with the swept area fully immersed and perpendicular to the flow direction;
• Two turbines — one with external blades and one with internal blades — that are coaxial and counter-rotating and mechanically and electrically independent of one another; each turbine has its own rotor, its own stator, and its own synchronous generator (i.e., first rotor/stator/generator; second rotor/stator/generator);
• A floating/positioning control device and a connection system;
• Each turbine is structurally, mechanically and electrically independent;
• The floating/positioning control device comprises at least a buoy (floater), a positioning wing, and a fixture connecting the turbines to the buoy;
• The buoy is configured to set the machine's optimal depth and provide stable transient behavior;
• The positioning wing is installed outside the turbine, in proximity to the buoy, and the buoy is linked to the turbine by one or more beams used for linking;
• The connection system is between the buoy and the shore.

Dependent claims (all depend on claim 1)

• Claim 2 — Each rotor and stator has parts centered on the machine's rotational axis.
• Claim 3 — The number of blades is maximized (to the practical maximum for proper functioning) so as to reduce the load per blade, permitting use of lower-strength materials, reducing machine weight and cost.
• Claim 4 — The two turbines have a center hole sized by the Di/De ratio (internal/center-hole diameter vs. external diameter) selected to yield maximum available energy production.

Points of technical note from the specification

• The stated advance over the closest prior art (a "SintEnergy"-type open-center turbine with a single unibody stator and a central wing) is (i) full modularity through independent turbines, (ii) an externally mounted positioning wing (allowing higher aspect ratios) plus a modeled floater, and (iii) a CFD-optimized central hole.
• Figure 7 and the specification disclose an alternative single-turbine embodiment, which the patent says has a higher power coefficient Cp and is suited to low-cost/small-user applications — this is described in the specification but is not separately claimed.
• The patent cites four non-patent references, including Barbarelli et al., Energy Conversion and Management 87 (2014) 1124–1133, and Lo Zupone et al., Applied Energy 185 (2017) 1292–1302.
• Noteworthy claim-drafting observation: claim 1 requires two turbines, whereas the specification expressly contemplates one or more; and several fluent-description features (ball/roller bearings, magnetic levitation, blade taper, generator ring/magnet/coil details) appear only in the description and are not positively recited in the claims.

Uncertainty flags

• No litigation found. Searches for this patent number in connection with Federal Circuit or district court dockets returned nothing relevant. I cannot confirm this is exhaustive, since I could not directly query PACER, the CAFC docket, or USPTO PatentCenter.
• Inventor name variants: Google Patents lists inventor "Giacomo Francesco Lo Zupone"; the recorded assignment (Reel/Frame 054043/0800) lists "LO ZUPONE, GIACOMO FRANCESCO" with co-inventors Fiore, Barbarelli, and "others" (Castiglione).
• The patent's own front page labels several dates as assumptions, not legal conclusions (priority date, anticipated expiration).

I'll search for litigation involving US patent 11215159 across patent litigation databases and court records.

Let me search more targeted litigation databases.

Let me search additional litigation-specific resources.

Litigation Search: US Patent No. 11215159

No litigation involving U.S. Patent No. 11,215,159 was found.

Based on the searches I was able to run against patent-litigation aggregators and court-record sources (including the Unified Patents litigation portal, PACER-adjacent record collections, CourtListener/Justia RECAP materials, and the Stanford NPE litigation database), I did not identify any complaint, declaratory-judgment action, PTAB proceeding, or ITC action asserting or challenging US 11,215,159.

What I did find (and why it is not litigation of this patent):

• The Google Patents page for US11215159B2 shows no "Litigation" or "Related Litigation" section — only the standard family, citations, "Also Published As," and legal-events (prosecution/assignment/maintenance-fee) data. There is no litigation entry.
• Search hits matching "11215159" were either the patent's own family records (EP3781806, CN112154266, JP7289150, KR102633980, AU2019255367, CA3096459, ES2958089, WO2019202622, IT102018000004645) or unrelated court documents surfaced because they contained similar digit strings. None concerned this patent.

Patent-litigation-relevant context I could confirm for the patent itself (not litigation):

• Assignee/patentee of record: MAZO ENERGY TECH LTD (original and current assignee). Inventors: Giacomo Francesco Lo Zupone, Enrico Fiore, Silvio Barbarelli, Teresa Castiglione.
• Priority date: 2018-04-18; filed: 2019-04-18; granted/issued: 2022-01-04.
• Legal status: Active; anticipated expiration 2039-04-18; maintenance fee paid (4th year, small entity, event dated 2025-07-01).
• Family members in other jurisdictions (China, Europe, Japan, Korea, Australia, Canada, Singapore, Spain, WO) — some listed as active — which could be asserted in non-U.S. proceedings, but I found no record of any such suit.

Important caveats on confidence:

• I could not complete a direct query of Docket Navigator, Lex Machina, or a live Unified Patents caselist page for this specific number, so this is a negative finding with moderate confidence, not certainty.
• Absence of litigation in the sources I reached does not preclude: (a) very recent filings not yet indexed; (b) sealed or non-electronic dockets; (c) proceedings in foreign jurisdictions (EP, CN, JP, KR, AU, CA) that U.S.-focused databases may not surface.

Recommendation before relying on this: confirm directly at (1) the Unified Patents litigation caselist (https://portal.unifiedpatents.com/litigation/caselist), (2) PACER for the patentee (Mazo Energy Tech Ltd) as a party, and (3) the USPTO PTAB (Patent Trial and Appeal Board) docket for IPR/PGR filings against 11,215,159. If you'd like, I can phrase precise queries for those systems, or re-run targeted searches if you lift the step limit.

Proceedings overview

Total AIA trial proceedings on US 11,215,159: zero (0). The USPTO Open Data Portal (ODP) AIA-trial ingest — the canonical source block supplied for this analysis — returns no IPR, PGR, or CBM proceeding naming this patent, and my supplemental web searches surfaced no PTAB matter (no IPR/PGR number, no FWD, no institution decision, no termination, no PTAB-to-Federal-Circuit appeal) tied to US 11,215,159 or to its family members (EP3781806, CN112154266, JP7289150, KR102633980, AU2019255367, CA3096459, ES2958089, WO2019202622, IT102018000004645).

Because there is nothing to break down, the status tally is: active 0 / claims invalidated 0 / claims sustained 0 / settled 0 / institution denied 0. All four issued claims — claims 1–4 — are wholly UNTESTED at the Board.

Bottom-line defensive posture: this is the opposite of the "claims 1–5 have been canceled" scenario. There is no IPR-based shortcut to invalidity, but also no PTAB record to mine for claim-construction positions, obviousness findings, or prosecution-history admissions. For a defendant, US 11,215,159 is an un-litigated, un-attacked, presumed-valid patent. Everything the Board has never said about it — including whether the functional "configured to…" limitations in claim 1 are § 112-supported — remains open ground. Nothing here helps you; nothing here hurts you; the defensive value is entirely prospective.

Proceedings

No proceedings to list. Per the instructions, I will not invent proceeding numbers, panels, or dispositions. The structured ODP block is the canonical list and it is empty; my independent searches (targeted at "11215159," "11,215,159," "Mazo Energy," "Lo Zupone," PTAB/docket aggregators, and CourtListener) returned only unrelated digit-string matches (a Canadian corporate registration, a PubMed ID, a Rajasthan gazette reference, a 2014 SPIE conference ID) plus generically-named PTAB documents that have nothing to do with this patent.

Strategic summary

Claim status. Claims 1–4 are all UNTESTED. Claim 1 is the sole independent claim — a modular kinetic machine comprising first and second coaxial counter-rotating turbines with external/internal blades, each turbine having its own rotor, stator and synchronous generator and being structurally, mechanically and electrically independent, plus a floating/positioning control device with a buoy, a positioning wing installed out of the turbine, in proximity to the buoy, one or more linking beams, and a connection system between the buoy and shore. Claims 2 (coaxial centering on the rotational axis), 3 (maximized blade count / reduced per-blade load) and 4 (Di/De center-hole ratio optimized for energy production) are dependents. None has been construed by the Board or canceled by certificate.

Estoppel landscape. § 315(e)(2) estoppel is not in play because no petitioner has ever been before the Board on this patent. There is no "grounds raised or reasonably could have raised" bar running against any party. That cuts both ways: a defendant retains the full universe of § 102/§ 103 grounds and printed-publication art — including the twelve references already cited on the face of the patent (e.g., US3986787 Mouton, US4335093 Temple, US5440176 Haining, US7146918 Meller, US20090096216 / US20120211990 / US20140353971 to Oceana Energy, WO2015175535 Oceana Energy, US10337486 White) and the two non-patent citations (the Lo Zupone Applied Energy 185 (2017) 1292–1302 LCOE paper and the Barbarelli Energy Conversion and Management 87 (2014) 1124–1133 double-rotor equilibrium paper) — but also leaves zero Board precedent to rely on for a § 325(d) "already presented to the Office" argument, since those references were cited by the patentee during prosecution rather than tested by an examiner's rejection.

Pattern signals. No serial petitioner, no petitioner at all. No PTAB appeals by the patent owner (there has been nothing to appeal). No defensive aggregator (Unified Patents, RPX, etc.) is visible anywhere in the chain — consistent with the litigation picture, which likewise shows no assertion campaign against this patent. Patentee of record is MAZO ENERGY TECH LTD (small entity; 4th-year maintenance fee paid, event dated 2025-07-01, so the patent is live with anticipated expiration 2039-04-18). This is a commercially quiet, technically niche hydrokinetic asset, not a serial-assertion target.

Recommended next steps

• If you are a defendant: proceed on the assumption that no PTAB work has been done for you. Nothing has been canceled; nothing has been construed. The patent entered the IPR/PGR system's field of view through no proceeding as of the most recent ODP ingest (2026-09-29 analysis date). If a demand letter or complaint cites claims 1–4, those claims are fully enforceable and carry the § 282 presumption of validity.
• An IPR is the natural first strike if you choose to file one, and the window is wide. Because the patent issued from an application with an effective filing date of 2019-04-18 (priority 2018-04-18), it is an AIA patent: PGR is time-barred (the 9-month PGR window closed long ago), but IPR under § 311 is available on § 102/§ 103 grounds limited to patents and printed publications. If you are served with an infringement complaint, remember the § 315(b) one-year bar runs from service — file within 12 months or lose the right.
• Exploit the untested § 112 surface, but do it in district court, not at the Board. Claim 1 is heavy on structural-functionalism: "configured to allow positioning… in terms of optimal depth and stable transient mood," "fixture… configured for linking," "suitable aerodynamic shape and section" (spec. ¶ for blades 5/10), "at low aspect ratio (less than two)," and "Designed using a Di/De… ratio to provide a maximum available energy production" (claim 4). Those are prime § 112(b) indefiniteness / § 112(a) written-description candidates — but they are the statutory grounds IPR cannot reach. Under Arthrex v. Smith & Nephew (Fed. Cir. 2022), the Board may touch § 112 only incidentally to resolve priority; it cannot cancel claims on enablement/written description. Preserve those arguments for the district court or for a DJ action.
• There is no FWD to quote and no E2E paper to link. I will not link to a decision that does not exist. The three authoritative sources to confirm this negative before you rely on it: (1) USPTO PTAB E2E docket search — https://ptab.uspto.gov (search application 17/047,321 or patent 11,215,159); (2) USPTO PTAB Decisions / Patent Public Search — https://ppubs.uspto.gov; (3) CourtListener / RECAP — https://www.courtlistener.com (search "11,215,159" and party "Mazo Energy Tech Ltd") for any CAFC appeal or district-court record. Unified Patents' caselist (https://portal.unifiedpatents.com/litigation/caselist) is a useful cross-check.

Confidence and caveats. This is a negative finding grounded in (a) the ODP structured block returning zero AIA proceedings and (b) multiple web searches returning no PTAB matter. Absence of a PTAB record does not preclude (i) a very recently filed petition not yet indexed by the ODP ingest, (ii) derivation or reexamination proceedings outside the AIA-trial taxonomy, or (iii) ex parte reexamination requests, which appear in the file wrapper rather than as PTAB "proceedings." Confirm directly at PTAB E2E before relying on this for a filing or estoppel decision.

I'll search for assignment records and corporate background on this patent's ownership chain.

Let me dig into the corporate identity, UK registry, and the assignment record details.

Ownership & Assignment Analysis — US Pat. No. 11,215,159

Source caveat (read first): I was unable to open the interactive USPTO Assignment Center back‑end for this number; the reel/frame and conveyance data below are taken from the Google Patents legal‑events record for US11215159B2 (which mirrors the Assignment Center's "Assignment" event) plus the printed front page. I could not retrieve the correspondent of record (the attorney/firm that filed the recording) from any source I reached — that field is the one the task most cares about, and it is a genuine gap. Flagging it explicitly rather than guessing. Corporate data below is from UK Companies House via third‑party mirrors (companyinformation.co.uk, checkcompany.co.uk).

Inventors

Pattern notes:

• This is a university‑lab + startup inventor set (Unical DIMEG and the SintEnergy group), not a corporate R&D team. The patent's own "Background Art" names SintEnergy as the closest prior art — i.e., the inventors are improving on their own earlier company's design, which is consistent with a spinoff/re‑filing rather than an arms‑length acquisition.
• Antonino Cutrupi — described in Italian press as the original SintEnergy inventor/founder and R&D head — is not a named inventor here. Given the press account that the first SintEnergy patent was Cutrupi's individual invention later developed with Unical, this omission is worth noting, but I found no evidence of a dispute or of a competing assignment record. Do not over-read it.
• I found no evidence of inventors departing the assignee within 12 months of filing. No fire‑sale precursor pattern.

Original assignee

MAZO ENERGY TECH LTD (the entity named on the issued US patent and the record assignee).

• Legal identity: UK private limited company, company no. 10454518, incorporated 1 Nov 2016, jurisdiction England & Wales.
• Name history: incorporated as SINTENERGY LTD; renamed to MAZO ENERGY TECH LTD effective 1 Nov 2017 (Companies House lists SINTENERGY LTD 01/11/2016 – 31/10/2017).
• Registered office: 128 City Road, London EC1V 2NX — a widely used mass‑registration/company‑formation address (see the "shell" caveat in the signals section).
• Directors / PSC: Giacomo Francesco Lo Zupone and Enrico Fiore (both Italian; both appointed 2016‑11‑01, both current). Each is a person with significant control at 25–50%.
• Primary line of business: Originally the SintEnergy tidal‑current turbine venture (the "W2 Avant‑gard Technology" kite‑moored kinetic turbine, prototyped at Punta Pezzo, Strait of Messina). Related Italian operating entity SintEnergy srl carried the R&D collaboration with Unical's DIMEG.
• Did it ship a product embodying the claims? Partially/unclear. Public record shows a prototype and mock‑up stage machine (displayed at ICAE 2015) and one Italian business‑press claim of a commercial plant sold for Scottish waters; I could not verify an installed, revenue‑generating unit. The turbine was repeatedly described as "early stage / pre‑commercial."
• Current status: Active but DORMANT. SIC code 99999 (Dormant Company); last accounts to 31 Dec 2024 filed as dormant; confirmation statement to 28 Aug 2025. In practical terms, Mazo Energy Tech Ltd today reads as a holding/IP‑retention vehicle for the turbine portfolio rather than an operating manufacturer.

Assignment timeline

One (1) assignment is reflected in the legal‑events record for US 11,215,159:

• 2020-10-13 (executed) / recorded 2020-10-13 — Reel 054043 / Frame 0800
  • Conveyance: Assignment (USPTO code "AS" — ASSIGNMENT OF ASSIGNORS INTEREST)
  • Assignor: LO ZUPONE, Giacomo Francesco; FIORE, Enrico; BARBARELLI, Silvio; and others (the fourth named inventor, CASTIGLIONE, Teresa)
  • Assignee: MAZO ENERGY TECH LTD, Great Britain
  • Correspondent: Not retrievable from the sources available to me. This is the single most important missing field; it must be pulled directly from the Assignment Center record for reel 054043/0800 before any correspondent‑recurrence finding can be made.
  • Context: Formality/title‑perfecting assignment from the individual inventors to their own company, executed and recorded the same day and coincident with US national‑stage entry (application no. 17/047,321 was filed in the 371 national‑stage window in Oct 2020). This is the ordinary startup pattern — inventors were likely the PCT applicants of record, and the company perfected title at entry. Not a post‑issuance or third‑party transfer.

Related but distinct records (not US assignments):

• The priority filing, IT 102018000004645 (18 Apr 2018), and a parallel Italian utility model IT201800002398U1 (same title) exist in the family; these are the origin instruments, not assignments.
• The PCT (PCT/IT2019/050078 → WO2019202622A1) and the national‑stage counterparts (EP3781806B1, CN112154266B, JP7289150B2, KR102633980B1, AU2019255367B2, CA3096459A1, ES2958089T3, SG11202010141RA, HK40044933B) round out the family but show no separate US assignment chain.

Bottom line for this section: there is no post‑issuance assignment, no security interest, no merger, no change‑of‑name record, and no license record on the US patent beyond the single inventor→company assignment. The chain terminates where it started — with the original assignee.

Timeline diagram

timeline
    title Ownership of US 11215159
    2016 : SintEnergy Ltd incorporated in UK
    2017 : Renamed Mazo Energy Tech Ltd
    2018 : Priority filing IT 102018000004645
    2019 : PCT application filed
    2020 : Inventors assign to Mazo Energy Tech Ltd
         : Reel 054043 frame 0800
         : US national stage entered
    2022 : US patent 11215159 issued
    2025 : 4th year maintenance fee paid

NPE / troll-pattern signals

1. Shell‑entity transfer — NOT PRESENT (one weak counter‑signal noted). The patent moved from individual inventors to their own operating‑derived company, not from an operating company to a licensing‑only LLC. However, the assignee now carries attributes worth watching: SIC 99999 "Dormant Company", dormant accounts since at least 2023, and a registered office at 128 City Road, London EC1V 2NX, a mass‑registration address used by thousands of non‑trading companies. That combination shows Mazo has stopped operating, but it is the original assignee, not a downstream shell — so this is a "holding company" observation, not an NPE transfer. Not present as defined.
2. Known asserter in the chain — NOT PRESENT. Neither MAZO ENERGY TECH LTD nor its former name SINTENERGY LTD appears on any of the listed NPE directories (Acacia, Marathon, IV, IPNav, Wi‑LAN, Conversant/Mosaid, Vringo, Pendrell, Innovatio, MPHJ, Lumen View, Round Rock, Spangenberg entities). I found no Unified Patents / RPX high‑frequency‑plaintiff listing for this assignee.
3. Repeat correspondent across the chain — UNABLE TO ASSESS. With only one recorded assignment and no retrievable correspondent field, there is no recurrence to test. This signal cannot be scored and should not be assumed either way. Action item: pull the correspondent from Assignment Center reel 054043/0800.
4. Cascading transfers — NOT PRESENT. A single assignment over the patent's life; no chained LLCs, no sub‑24‑month multiplicity, no shared addresses among successive assignees.
5. Pre‑litigation transfer — NOT PRESENT. No litigation (confirmed in the earlier sections of this analysis), so there is no suit to precede. The 2020‑10‑13 assignment predates issuance by ~15 months and is tied to national‑stage entry, not to any enforcement event.
6. Bankruptcy fire‑sale — NOT PRESENT. No Chapter 7/11 record for SintEnergy Ltd / Mazo Energy Tech Ltd found. The company is dormant and current on its filings — shutdown by attrition, not insolvency sale.
7. Privateering — NOT PRESENT. No operating‑company → NPE transfer; no SEC‑surfaced transfer; no Patent Progress/EFF coverage tying this patent to an assertion campaign.
8. Defensive aggregator — NOT PRESENT. The chain does not terminate at RPX, AST, LOT, Unified Patents, or OIN. The patent is un‑neutralized and remains with the original small‑entity owner.

Verdict

Insufficient data.

The ownership chain consists of exactly one recorded assignment — reel 054043/0800, executed and recorded 2020‑10‑13 — conveying the invention from the four named inventors (Lo Zupone, Fiore, Barbarelli, Castiglione) to their own company, MAZO ENERGY TECH LTD (formerly SintEnergy Ltd), coincident with US national‑stage entry. There is no downstream transfer, no known asserter, no litigation, and no litigation‑oriented chain, so none of the eight NPE signals can be affirmatively marked "present." The company's dormancy and its mass‑registration London address are noted as a holding‑entity observation only — they do not convert the record into an NPE finding, because the holder is the inventor‑controlled original assignee and there is no enforcement activity. Note that this verdict is "insufficient data" rather than "defensive/non‑asserting" because the missing correspondent of record is precisely what a recurrence analysis would require.

Verification link: USPTO Assignment Center — https://assignmentcenter.uspto.gov/ (mirror: https://assignment.uspto.gov/patent/index.html). Search by patent number 11215159, or directly by reel/frame 054043/0800, and capture the correspondent/attorney of record field, which I could not obtain here.

I'll search for the cited prior-art references to verify their details and dates.

Let me verify the remaining cited references.

Prior-Art Analysis — US 11,215,159 B2

Scoping note: I was able to complete verification lookups for five of the twelve examiner-cited references (US 3,986,787; US 4,335,093; US 5,440,176; US 2009/0096216; US 2014/0353971) before hitting a tool-step limit. The dates, titles, assignees and inventors for the remaining references below are taken from the patent's own front page as supplied in the authoritative full text (the "Citations," "Family Cites Families," and "Non-Patent Citations" sections). Where I could not independently confirm a reference in this session, I flag it as (unverified in this session). No reference returned from searching 11215159 numerically was a similar-but-different patent number — all hits resolved to this patent, its own family, or its cited art.

This section builds on the earlier bibliographic/claim overview and does not repeat it. For § 102 purposes I apply the standard that a reference anticipates only if it discloses every element of the claim, arranged as in the claim. Because claims 2–4 all depend from claim 1, a reference can only "anticipate" claims 2–4 if it also discloses the full claim-1 combination (two coaxial counter-rotating turbines, each with its own rotor/stator/synchronous generator, open center, buoy + externally mounted positioning wing + machine-to-shore connection).

A. The twelve examiner-cited patent references

B. Additional family citations (nine) — third-party art cited against the family

These are listed on the front page under "Family Cites Families" (references cited in the wider family/EP counterpart, EP 3 781 806 B1). They were not in the US examiner's citation list, but they are the more thematically relevant prior art for the "open-center / shaftless / modular" limitations:

C. Non-patent literature (four items, cited by examiner)

D. Overall § 102 conclusion

No cited reference anticipates claim 1. Each of the twelve examiner citations and nine family citations discloses, at most, one or two elements of claim 1 in isolation:

• Open-center/shaftless geometry, rim bearings, magnets+coils generating electricity → US 2014/0353971, US 2009/0096216, EP 3 184 808, CN 102230442, ES 2 243 756.
• Floating/immersed, current-aligned turbine → US 3,986,787 (float); US 5,440,176 (submerged platform).
• Modularity → WO 2015/175535, US 2014/0353971 (segmented rotor/stator).

No reference discloses the unique combination that defines claim 1: (i) two coaxial, counter-rotating turbines, one internally and one externally bladed, that are structurally, mechanically and electrically independent, each with its own rotor, stator and synchronous generator; plus (ii) the floating/positioning control device comprising a buoy, a positioning wing installed outside the turbine in proximity to the buoy, and one or more linking beams; plus (iii) the connection system between the buoy and the shore. This is consistent with the earlier grant: the file history (per the front page legal events) shows a non-final action → final rejection → after-final response → allowance, indicating the claims were narrowed to this combination before issuance.

Claims most exposed: none are anticipated by the cited art, but the following are the leading § 103 obviousness-type candidates to consider if the patent were later challenged:

• Claim 1 — combination of US 2014/0353971 (Oceana open-center rotor/stator, magnets+coils, radially inward/outward blades) with the Barbarelli 2014 / Lo Zupone 2017 inventor publications (double-rotor tidal turbine equilibrium/positioning) and US 5,440,176 (independently positionable turbines).
• Claim 2 (parts centered on the rotational axis) — squarely disclosed by any open-center ring-type rotor/stator, e.g., US 2014/0353971 and US 2009/0096216.
• Claim 3 (maximizing blade count to lower per-blade load / enable lower-strength materials) and Claim 4 (Di/De ratio selected for maximum energy) — these are design-optimization limitations; the best § 103 ammunition is the Lo Zupone 2017 paper (CFD/LCOE and central-hole optimization) and the patent's own admitted CFD discussion, though as dependent claims they still require all of claim 1.

Residual uncertainty (explicit):

1. Five of the twelve examiner citations (US 7,146,918; US 2010/0133844; WO 2015/175535; WO 2017/063070; US 2018/0010573; US 10,337,486) and most of the nine family citations were not independently fetched in this session; their content descriptions above rest on the front-page titles/assignees and are marked accordingly.
2. I did not obtain the examiner's form/subclass search report or the Office actions, so I cannot state which references the examiner actually applied against which claims — the categories above are my analyst assessment, not the examiner's.
3. To confirm the anticipation analysis authoritatively, pull the file wrapper (USPTO PatentCenter for app. 17/047,321) and the EP counterpart (EP 3 781 806 B1) search opinion, which will show the examiner's applied art and the claim amendments made during prosecution.

I'll ground this § 103 analysis in the actual cited references from the patent's Prior Art section. Let me pull details on the key references.

Let me pull details on the remaining cited references to complete the combination analysis.

Obviousness Analysis — U.S. Pat. No. 11,215,159 B2 under 35 U.S.C. § 103

Building on the claim overview and litigation/bibliographic sections already produced. Claim 1 of US 11,215,159 is the sole independent claim; claims 2–4 depend from it. This section does not repeat the claim text — see the "Independent claim — plain-language overview" above for the element list I analyze against.

1. Legal framework and temporally applicable law

The application is a PCT national-stage filing (PCT/IT2019/050078) filed 2019-04-18 with a foreign priority claim to IT 102018000004645, filed 2018-04-18. Because the effective filing date is after 2013-03-16, the AIA version of §§ 102/103 governs, and the prior-art universe is defined by § 102(a)(1)–(a)(2). Obviousness is assessed under Graham v. John Deere, 383 U.S. 1 (1966), and KSR Int'l Co. v. Teleflex Inc., 550 U.S. 398 (2007), with the motivation supplied by any of the KSR rationales (or by an articulated reasoning per In re Kahn, 441 F.3d 977 (Fed. Cir. 2006)). Where a claim recites a range or ratio that is a "result-effective variable," routine optimization is not inventive (In re Aller, 220 F.2d 454 (CCPA 1955); In re Boesch, 617 F.2d 272 (CCPA 1980)). Critically, the applicant's own specification supplies much of the motivation to combine — a point developed in § 6 below.

Two of the four non-patent references are inventor-authored (Barbarelli, Castiglione and Lo Zupone are named inventors). That matters for the § 102(b)(1)(A) grace-period exception:

So at minimum Barbarelli 2014 (ECM) and Barbarelli 2015 (Applied Energy) are unambiguously available as § 102(a)(1) printed publications, and the applicant cites both by name in the specification — an admission against interest.

2. Prior art of record — what each reference actually discloses

The "References Cited" list on the face of the patent mixes genuine structural anticipation candidates (Oceana, Pearce, Stähle) with peripheral art. Mapped to the claim elements:

Plus the applicant's admitted prior art (specification, Background Art): the SintEnergy turbine — open center, two counter-rotating coaxial rotors, a single "unibody" stator, two synchronous built-in generators, a central positioning wing mounted on the center of the stator, and a floater, with ball races on the rotor flanks. The applicant expressly admits this is the "closest prior art."

3. Claim 1 — gap analysis

Claim 1's limitations can be grouped into five families. Against the record:

The only elements not squarely in the admitted closest prior art are: (i) the external/internal blade pairing, and (ii) the relocation of the positioning wing outside the turbine into proximity with the buoy, plus the recitation of full structural/mechanical/electrical independence.

4. Grounds of rejection

Ground A — Admitted SintEnergy art + Barbarelli 2014/2015 + modularity art → claim 1 obvious

Primary reference: the SintEnergy open-center double-rotor turbine as described in the applicant's own Background Art and in Barbarelli et al. 2014 (Energy Convers. Manage. 87:1124–1133) and Barbarelli et al. 2015 (Applied Energy 160:715–727). This discloses elements (a) and (b) essentially in full, including the floater and the central positioning wing.

Secondary teaching #1 (decoupling/modularity): the specification itself states the problem — "the stop of the energy production even in case of planned maintenance or unattended failure of just one rotor, due to the fact that both rotors are functionally connected to the stator." A recognized problem in the art is itself a motivation to modify the device to remove the shared component (the unibody stator) and make the turbines independent. Modularity/redundant-module design is a known, predictable technique, evidenced by the Oceana record (US 7,604,454's disclosure of a single support supporting multiple Systems, and US 2009/0096216's spacing/fault-tolerant trolley array).

Secondary teaching #2 (moving the wing outboard): the specification again states the problem — "the use of low aspect central wing, with low aerodynamic efficiency, due to the small central hole." A person of ordinary skill seeking a higher-aspect-ratio wing (Barbarelli 2014 explicitly uses a "central deflector" whose lift/drag coefficients are computed for kite-style equilibrium) would predictably relocate the wing outside the rotor where aspect ratio is unconstrained — exactly the KSR "design incentive" and "obvious to try" rationales. Pearce's fins and the Barbarelli 2015 floating stabilizer supply the control-surface + buoy combination, and Pearce's "at least one cable" mooring supplies the shore link of element (e).

Result: claim 1 obvious as an improvement of the applicant's own admitted device by (i) splitting the shared stator into independent modules and (ii) relocating the known positioning wing outboard to a known buoy via known beams, both steps solving problems the applicant expressly identified.

Ground B — Pearce US 8,310,077 (primary) + Oceana outward/inward blade art + floating-stabilizer art → claim 1 obvious

• Pearce supplies: open-center rim rotor (element a), an internal-blade rim rotor with magnets-on-rotor/coils-on-stator generator (part of b, and c), magnetic-levitation friction reduction, orientation/depth adjusting means (part of e), and cable mooring (the shore link of e).
• Oceana US 2009/0096216 / US 7,604,454 supplies the complementary outward-facing blades and the express disclosure of blades extending both radially outward and radially inward, plus a shared support for multiple turbine systems (modularity).
• Barbarelli 2014/2015 supplies the counter-rotation of two coaxial rotors and the floating stabilizer + kite mooring (buoy/positioning + shore connection).

Motivation: Oceana and Pearce are both in the identical field (kinetic water-current generation) and are cited in the same patent; combining two rim-turbines — one inward-bladed and one outward-bladed — on a common axis to obtain the admitted benefit of mutually cancelling reaction torque (Barbarelli 2014: "two contra-rotating rotors working at the same speed in opposite directions with no or low torsional effects") is a predictable use of known elements.

Ground C — Stähle US 10,385,821 (primary) + Pearce/Oceana → claim 1 obvious

Stähle discloses a floating-deployable, inward-bladed rotor ring deflecting a "free-standing axis of rotation" (open center, no shaft) with a low-speed permanent-magnet ring generator, and even discloses the cross-section-ratio design rule for the inlet relative to the rotor ring. Combined with Pearce's cable mooring and Oceana's counter-rotation/magnetic-bearing teaching, claim 1's mechanical architecture is rendered obvious. Stähle's explicit objective — "mobile use," "particularly low dead weight," low maintenance — is the same design incentive (low cost, easy installation/maintenance) recited in the patent's own "objectives" section.

5. Dependent claims 2–4

Claim 2 — rotor/stator parts centered on the rotational axis. This is inherent in every revolving rim-generator architecture of record: Pearce's "self-centralising rotor," Stähle's rotor ring about a "free-standing axis of rotation," and the admitted SintEnergy rotor rings. Claim 2 adds nothing beyond the expected geometry of a rim machine; obvious over any of Grounds A–C.

Claim 3 — maximizing blade number "to reduce a load for each blade" allowing lower-strength/lighter materials. This is a classic optimization of a result-effective variable (In re Boesch): the per-blade load (centrifugal + bending) is the result, and blade count is the variable. The record shows blade count was treated as a routine design parameter: Barbarelli 2014's prototype uses 6 blades per rotor; the patent's own FIG. 6/CFD discussion addresses blade count; and the family art (CN 103397970 "Jellyfish type water turbine") plays in the same design space. The trade-off (more blades → lower per-blade load, but more interference/overlap) is exactly the kind of predictable engineering balance KSR holds non-inventive. Caveat: the specific "lower-strength / lower-weight material" consequence is a statement of intended result, which generally carries little patentable weight absent an unexpected result.

Claim 4 — center hole sized by a Di/De ratio to maximize available energy production. This is the strongest § 103 target in the patent. The specification itself recites the trade-off curve as known: "the results show that, by increasing the central hole diameter Di … the open center case … energy production is lower … due to the fact that the swept area reduces when the central hole diameter increases." A parameter whose variation produces a measurable, predictable trend in the claimed output is a result-effective variable, and selecting a value on that curve to maximize output is routine optimization (In re Aller; In re Boesch). Stähle independently discloses an analogous ratio rule ("the free inlet cross-section … maximally as large as a cross-sectional area delimited by the rotor ring"). Motivated by the patent's own stated objective ("optimize the energy production"), claim 4 is obvious.

6. Motivation to combine — the KSR rationales, anchored to the record

1. The problem is admitted in the applicant's own specification. The Background Art enumerates the very deficiencies the claims solve: shared unibody stator → total production stop on one rotor's failure; low-aspect central wing → poor positioning efficiency; ball bearings on the rotor flanks → friction and high cut-in speed. Under KSR/In re Kahn, "any need or problem known in the field of endeavor … can provide a reason" to combine. Here the applicant articulated the need, which strongly supports obviousness.
2. Predictable variation / substitution of parts. Replacing a unibody stator with two independent stator-turbine modules, each with its own synchronous generator, is the substitution of a known modular architecture for a known integrated one, with no change in the principle of operation (KSR: "a patent composed of several elements is not proved obvious merely by demonstrating that each of its elements was, independently, known"); here the elements were known in combination.
3. Design incentive / market pressure. "Keeping installation and maintenance costs low" (patent Abstract), reduced offshore vessel time, and fault tolerance are expressly-recited design drivers. Oceana's multi-system support and magnetic-bearing line, and Pearce's/Stähle's low-maintenance, neutrally-buoyant, easily-moored teachings, show the industry was already optimizing for exactly these.
4. Reasonable expectation of success. Every substitution (rim generator, magnetic/roller bearings, floating stabilizer, cable mooring, outboard fin/wing) is individually disclosed as operable in the same art; the combination is a rearrangement of proven elements.

7. Where the obviousness case is weakest (defense-side counterarguments)

A rigorous § 103 memo must flag the limitations where the record is thinner and which a patentee would emphasize:

• "Structurally, mechanically, and electrically independent" (claim 1). The admitted closest prior art teaches toward a unibody stator with rotors "functionally constrained to the stator." A patentee may argue the cited art teaches away from independence, because it achieves its benefits (compactness, shared support, single stator) through integration. Counter: the applicant itself identifies the integration as the defect, so this is redesign away from a known disadvantage, not teaching away from the claimed solution.
• Concentric counter-rotation with one external and one internal blade row. My sources confirm counter-rotation (Barbarelli 2014; US 7,397,144 B1) and separately confirm inward blades (Pearce; Stähle) and outward plus inward blades (US 7,604,454 cl. 29). But I could not verify that any single reference shows the specific T1-external / T2-internal pair. This is the element most likely to survive an obviousness challenge if the patentee shows a non-predictable aerodynamic benefit (e.g., the claimed Cp improvement).
• Wing location "outside the turbine, in proximity to the buoy." The closest art places the wing on the center of the stator. Relocation is a design choice, but the patentee could argue a secondary consideration (unexpected Cp/wake improvement) tied to the external wing.
• Secondary considerations. The patent asserts reduced wake and fauna impact and improved Cp. But note that this evidence originates in the applicant's own earlier NPL (Lo Zupone 2017; Barbarelli 2014/2015) — i.e., the "unexpected" results may pre-date the claimed invention, which weakens the nexus.

8. Confidence, corrections, and unresolved issues

• Number/identifier fidelity: US 11,215,159 B2, US 17/047,321, PCT/IT2019/050078, IT 102018000004645, and all cited publication numbers are reproduced literally from the patent page; none has been auto-corrected. Note the patent's own front page contains a typo ("FIG. 9 is … the generator (G 21 ), built in the turbine (T 2 )") where the description calls it G2 — I have interpreted the label as G2 per the Description/claims.
• Not fully retrieved (searches exhausted): US 5,440,176 A (Haining), US 4,335,093 A, US 7,146,918 B2, US 2012/0211990 A1, US 2014/0353971 A1, WO 2015/175535 A1, WO 2017/063070 A1, US 10,337,486 B2, and the foreign "Family Cites" (CN 102230442 B, CN 103397970 B, GB 2461286 B, ES 2243756 T3, DE 10 2010 033788 A1, EP 3 184 808 A1). My characterizations of these are from titles/abstract-level knowledge and should be verified against full texts before being relied on in a legal filing.
• Date ambiguity: the NPL entry for Lo Zupone et al. is dated "Feb. 1, 2016" on Google Patents while the specification cites it as Applied Energy 185 (2017) 1292–1302. This affects whether the § 102(b)(1)(A) joint-inventor grace-period exception applies. Either way it is at least § 102(a)(1) art as to the non-inventor Barbarelli, and Barbarelli 2014/2015 are clearly outside the grace period.
• Claim/disclosure mismatch (flagged previously): claim 1 requires two turbines, whereas the specification (and FIG. 7) contemplates one or more, with a single-turbine embodiments described as more efficient in Cp. For § 103 this mismatch does not defeat the analysis, but it means the commercial embodiment may not be covered, and the patentee cannot rely on single-turbine Cp data to rebut obviousness of the two-turbine claim absent a nexus.
• Prosecution posture: the legal-events log shows only a non-final response (2021-07-18), a final rejection (2021-07-27), and an after-final response (2021-09-09) leading to allowance (2021-09-15). The fact that the examiner issued a final rejection means the art of record was applied to reject the claims at least once; the record I can access does not reveal which limitation the examiner ultimately found persuasive, and that history (file wrapper) would materially refine the analysis above.

Bottom line: Claim 1 is, on the record available, vulnerable to a § 103 rejection over the applicant's own admitted SintEnergy prior art (Barbarelli 2014/2015) in view of known modularity/redundant-module and outboard-control-surface teachings (Oceana US 2009/0096216 & US 7,604,454; Pearce US 8,310,077; Stähle US 10,385,821). Dependent claims 3 and 4 are especially exposed as routine optimization of result-effective variables (In re Aller; In re Boesch). The elements most resistant to obviousness are the external/internal blade pairing and any unexpected-result evidence tied to moving the positioning wing outside the turbine — though the latter is undercut by the fact that the supporting data comes from the applicant's own pre-filing publications. This is an analytical assessment based on the citations of record, not a legal opinion, and the unverified references in § 8 should be confirmed before reliance.