US 11274883

I'll search for authoritative records on this patent number and any 2026 CAFC docket activity.

Let me run more targeted searches for litigation and Federal Circuit activity.

Summary — U.S. Patent No. 11,274,883 B2

Verification note: I relied on the full patent text you supplied as the authoritative source, and cross-checked it against publicly indexed records. Everything below is confirmed by that text; where I could not confirm something, I say so explicitly. I did not find any authoritative evidence of CAFC or PTAB activity involving this specific patent (details at the end).

Bibliographic data

Abstract (as issued)

A fluid heating process which does not utilize an open flame, heat is created by a rotating prime mover(s) driving a hydraulic heat generator. Heat is also collected from the prime mover cooling system, and any exhaust heat generated by the prime mover. The heat energy is collected from all these sources, and transmitted through heat exchangers to generate a hot fluid, which can be used to heat other fluids and used for any application where heat is required.

Family / prosecution context

• This patent is a continuation of Application No. 14/037,123, which issued as US 10,408,548 B2 ("Flameless glycol heater"). The specification describes the same disclosure; note that the parent's claims are directed to an apparatus ("a flameless heater system"), whereas 11,274,883's claims are directed to a method.
• Related later filings: US 17/667,915 → US 11,874,069 B2 (continuation), and US 18/396,906 → US 2024/0133638 A1 (pending).
• Foreign counterparts in the family: EP 3049732 A1 (reported not active/withdrawn), CA 2828522 C (granted 2016-01-12), WO 2015/042709 A1 (reported ceased). I did not independently verify the current legal status of those foreign cases.

Independent claim — plain-language overview

Claim 1 is the sole independent claim. It recites a method for flamelessly heating a material, with these steps/structural requirements:

1. Circulating a fluid (the heated fluid, e.g., glycol) around a first closed circulation path using at least one pump.
2. Transferring heat, in a first heat exchanger, from a heating fluid (e.g., oil) that circulates in a second closed circulation path, to the fluid in the first path. Critically, the first heat exchanger sits in both circulation paths.
3. Transferring heat from the output of a prime mover (e.g., engine coolant and/or exhaust) to the fluid via at least one second heat exchanger.
4. Transferring heat from the fluid to the material to be heated (e.g., water in a tank) via a third heat exchanger located in the first closed circulation path.
5. Wherein a dynamic heat generator (the hydraulic/oil-shear heat generator) is arranged in the second closed circulation path and generates the heat that heats the heating fluid.

In plain terms: a closed glycol loop picks up heat from (a) a dynamic/shear heat generator via an oil loop, and (b) the engine's waste heat; then it dumps that heat into the target material. The two-loop, "heat exchanger shared by both loops" architecture is the core of the claim.

The remaining claims are all dependent:

• Claims 2–3 — pump specifics (pump moving fluid from a reservoir to the first heat exchanger; pump circulating heating fluid in the dynamic heat generator).
• Claims 4–6 — fluid identities (fluid = glycol; heating fluid = oil; material = water).
• Claim 7 — the prime-mover output comprises at least heated engine coolant and exhaust.
• Claims 8–9 — the second heat exchanger transfers heat from engine coolant, and/or from engine exhaust, to the fluid.
• Claim 10 — the second heat exchanger is air-to-fluid with a series of pipes; exhaust flows across the pipes to heat the fluid and cool the exhaust output.
• Claim 11 — the pipes are sized so exhaust output temperature is 20–25 °C.

Litigation / CAFC check (important caveat)

• I searched for CAFC 2026 docket activity on this patent number and found no records. I cannot confirm any Federal Circuit appeal, IPR, or district-court case involving US 11,274,883, and I have no authoritative information that any exists. Treat the litigation status as unknown/not found, not as "no litigation exists."
• A word of caution the user asked me to preserve: searching the bare string "11274883" returns unrelated non-patent hits — e.g., UK company MAKOIL GROUP LTD, company number 11274883, and a Brazilian JUCISRS corporate registration number 11274883. These are not the patent. I did not auto-correct or merge them into this record.
• Similarly, 2026 PTAB/IPR results that surfaced (e.g., IPR2026-00239 through IPR2026-00243 involving Apple Inc. and WeCrevention, Inc., concerning patents 9,164,942; 9,201,834; 10,998,017; 11,894,098; and 12,154,652) involve different patent numbers and are not related to US 11,274,883.

Sources

• Google Patents, US 11,274,883 B2 — https://patents.google.com/patent/[US11274883B2](/patent/US11274883B2)/en
• Google Patents, US 10,408,548 B2 (parent) — https://patentimages.storage.googleapis.com/70/51/af/92ab6eaa294992/US10408548.pdf
• PatentGuru, ConleyMax Inc. portfolio (bibliographic/inventor/agent confirmation) — https://www.patentguru.com/assignee/conleymax-inc
• OnScope, ConleyMax Inc. owner profile — https://onscope.com/ipowner/en/owner/profile/[295025](/patent/295025)-conleymax-inc.html

If you need litigation/PTAB/CAFC status confirmed to a legal standard, that would require a docket-level search (USPTO Patent Center, PTAB API, PACER/CAFC docket) — which I could not complete authoritatively here.

I'll search litigation databases and docket sources for this specific patent number.

The bare number keeps returning unrelated corporate registrations. Let me search by patent number with patent-specific terms and by the assignee/patent title.

Litigation Search Results — U.S. Patent No. 11,274,883

Bottom line

I found no litigation involving U.S. Patent No. 11,274,883 ("Flameless glycol heater," ConleyMax Inc.). No district-court complaint, no Federal Circuit appeal, no PTAB/IPR proceeding, and no ITC investigation asserting or challenging this patent surfaced in any of the searches I ran. I cannot confirm that litigation exists, and — equally important — I cannot certify that none exists, because I was not able to run a true docket-level query against PACER, the CAFC docket, or the Unified Patents litigation portal API. Treat the status below as "not found," not as "none exists."

What I searched, and what came back

Critical caution on the identifier

Per your standing instruction not to auto-correct identifiers, I note explicitly that searching the bare string "11274883" produces confident-looking but entirely unrelated records:

• MAKOIL GROUP LTD, UK company number 11274883 (Companies House; director appointment filed 13/02/2025; also appeared in a Gazette notice dated 06/11/2025). Not a patent, not a party to any patent case.
• A Brazilian JUCISRS corporate registration number 11274883.
• A 11274883 exchange-rate value in a Vanguard N-PORT filing.

These are not U.S. Patent No. 11,274,883 and must not be merged into the record. This is exactly the kind of collision that makes a bare-number search unreliable.

Why the negative result is plausible here

Context from the patent itself supports the absence of litigation rather than contradicting it:

• Assignee is a small operating company, not an NPE. ConleyMax Inc. (Calgary, Alberta) is listed as a small entity in the USPTO legal-events record (fee-status events of 2019-06-25 and 2019-07-03; 4th-year maintenance fee paid 2025-09-09). Small-entity operating companies in the oilfield-heater space rarely generate public infringement dockets.
• The family is domestic- and Canada-centric. Foreign counterparts are EP 3049732 A1 (reported withdrawn/not active) and WO 2015/042709 A1 (reported ceased), with CA 2828522 C granted. There is no evidence of parallel foreign enforcement activity either.
• The patent is a continuation, not an asserted patent with a distinct damages posture. Parent US 10,408,548 B2 (apparatus claims) and later US 11,874,069 B2 (issued 2024-01-16) would more typically be the vehicles for assertion. I found no litigation on the parent or sibling patents either — though, again, that is a "not found," not a verified negative.

Recommended verification path (docket-level, if a legal standard is required)

Because the web searches above cannot substitute for a docket check, obtaining a citable negative would require:

1. PACER / CourtListener RECAP — search "11,274,883" and "ConleyMax" across all district courts; CourtListener's RECAP docket search is the best free proxy for PACER.
2. CAFC docket — search the Federal Circuit's CM/ECF and the CAFC opinion/order databases for the patent number and "ConleyMax."
3. PTAB — USPTO Patent Center "Patent Trial and Appeal Board" tab for US 16/452,177 and the issued patent, plus the PTAB API (/ptab/v2/ endpoint) for patentNumber=11274883.
4. USPTO Assignment / Patent Center — confirm no assignment to a PAE or litigation funder, which is the leading indicator of imminent assertion.
5. ITC EDIS — Section 337 investigations, in case the heater technology was imported.

Contradiction / caveat flag

There is no contradiction between the earlier-generated patent summary and these findings — the prior section likewise reported no CAFC or PTAB activity and flagged the same bare-number false positives (MAKOIL GROUP LTD, the Brazilian JUCISRS number). That section was grounded in the supplied patent text and public bibliographic pages; these litigation-specific searches reinforce it. The one item I could not close out is the exact assignee/party-name search for any ConleyMax enforcement action, so please treat that as open rather than negative.

Summary answer: No known litigation involving US 11,274,883 is documented in the sources I could reach; if litigation or a PTAB challenge exists, it is not publicly indexed at the level my searches could access.

I'll verify the structured-data conclusion with targeted searches before writing up.

Let me run a few more targeted checks on related patents and possible litigation chains.

AIA Trial Proceedings — U.S. Patent No. 11,274,883 B2 ("Flameless glycol heater," ConleyMax Inc.)

Bottom line up front: there are no AIA trial proceedings on file against this patent. The structured "PTAB proceedings on file" block drawn from the USPTO Open Data Portal returns an empty set, and my independent web checks (PTAB trial decisions, IPR/PGR petition coverage, ConleyMax-as-patent-owner searching, and sibling-patent searching) surfaced nothing to the contrary. I am reporting the null result rather than manufacturing proceedings — do not treat any proceeding number below as real, because none are given.

Proceedings overview

Total AIA trial proceedings on US 11,274,883: 0. Breakdown by status is therefore 0 active / 0 claims invalidated / 0 claims sustained / 0 settled / 0 institution-denied.

The defensive posture this creates is the least favorable of the three possible postures. This is not the "conditions have been tested and the patent is hardened" scenario, and it is not the "claims 1–5 are canceled" scenario — it is the untested patent scenario. No challenger has ever put claims 1–11 in front of the Board, so every claim, including the sole independent claim 1, remains presumptively valid and fully live against you. The patent is also currently maintained — the Legal Events record shows a 4th-year maintenance fee paid 2025-09-09 (M2551, small entity) — so you cannot rely on lapse as a cheap exit. Treat the claims as fully enforceable and assume the patent owner has had zero adverse PTAB feedback on claim construction, which means the claim language in claim 1 (particularly "dynamic heat generator," "first heat exchanger arranged in both the closed circulation path and the second closed circulation path," and "output of a prime mover") has never been construed by an APJ panel.

For each proceeding

There are no proceedings to analyze. I will not generate placeholder entries. For completeness, here is what I searched and what I found:

• ODP structured dataset (canonical source): no AIA trial proceedings indexed against US 11,274,883.
• Web searches for IPR / PGR / CBM paired with the patent number and with the patent owner name ("ConleyMax"): no petition, institution decision, final written decision, or termination surfaced.
• Sibling/parent patents checked for a family-wide challenge campaign: US 10,408,548 B2 (parent, apparatus claims), US 11,874,069 B2 (continuation), US 11,230,993 B2 and US 12,196,155 B2 (flameless combo heater line), US 12,098,667 B2 (flameless fluid heater). I found no AIA trial activity on any of them either. If a defendant were running a coordinated family-wide IPR strategy, it would normally be visible here; it is not.
• False-positive guardrail (preserve): the bare string "11274883" continues to return non-patent hits such as UK company MAKOIL GROUP LTD, company number 11274883, and a Brazilian JUCISRS corporate registration number 11274883. Those are not this patent and were not merged into this record.
• Limitation on this conclusion: the absence of a record in ODP plus a negative web search is strong but not equivalent to a PACER/PTAB E2E API-level confirmation. If you need a litigation-grade representation, pull the PTAB E2E docket for the patent number and the assignment record directly.

Strategic summary

Claim status: all 11 claims UNTESTED

Because no AIA trial has ever been instituted, the statutorily mandated claim-by-claim ledger (canceled / sustained / untested) is empty on the first two columns and full on the third. Claims 1–11 are all UNTESTED. Nothing has been canceled, so nothing has been narrowed by the Board, and the patent owner has never had to defend the claims under the Board's Phillips-based construction standard. For a defendant, this cuts both ways: there is no helpful claim-cancellation record to point to, but there is also no adverse FWD claim construction that the patent owner can carry into your district court case and no prosecution-history narrowing that a court is locked into.

Note the intra-family claim-type split, which matters for how you plan: the parent US 10,408,548 B2 carries 16 apparatus claims, the patent at issue here (US 11,274,883 B2) carries 11 method claims with only claim 1 independent, and the continuation US 11,874,069 B2 carries apparatus claims with explicit closed-loop/water-tank limitations. A single IPR on the '883 patent would not, by itself, dispose of the family — see the estoppel point below.

Estoppel landscape — you are starting with a clean slate

Section 315(e)(2) estoppel is triggered only by a final written decision in a proceeding the petitioner (or its real party in interest or privy) brought. With zero AIA trials on this patent, no § 315(e)(2) estoppel exists against anyone. Practically, that means:

• Every § 102 and § 103 ground based on patents and printed publications is still available to a defendant. There is no "raised or reasonably could have raised" bar to work around.
• IPR estoppel under § 315(e)(2) is, as written, patent-specific — it is keyed to "the patent" in the proceeding. Because the Board has never decided anything here, you do not face the messier question of whether an estoppel from a sibling patent's IPR bleeds over to the '883 claims. (I flag that sibling-patent estoppel is a contested issue in district courts; I am not asserting a settled answer.)
• A prior district-court invalidity judgment is a different animal — nothing in my search suggests one exists, but if you are being asserted against, confirm that from the litigation docket rather than from patent databases.

Pattern signals

No challenger has filed even one petition, so there is no repeat-petitioner pattern (no General Plastic / follow-on serial-petition exposure for a new petitioner), no defensive-aggregator trail (I found no Unified Patents or similar entity in the chain — the assignment record shows a single assignment from the inventors to CONLEYMAX INC., effective 2013-09-24), and no patent-owner appellate activity, because there has never been a Board decision to appeal. The patent owner's prosecution-side behavior is the only signal available: the family has been kept alive through three continuations (14/037,123 → 16/452,177 → 17/667,915 → 18/396,906), which is consistent with an owner actively curating coverage rather than letting the portfolio lapse.

Time-bar and forum considerations you must check immediately

Two clocks are the whole ballgame if you are contemplating an IPR:

1. § 315(b) one-year bar. If your client has been served with a complaint alleging infringement of this patent, the petition must be filed within one year of service. This is jurisdictionally enforced and cannot be excused. Calendar it against your service date, not the filing date of any amended complaint's new claims.
2. PGR window is closed. The patent issued 2022-03-15. Under § 321(c), a PGR must be filed within nine months of grant, so a PGR was foreclosed around 2022-12-15. You cannot use PGR to reach § 112 or non-printed-publication art; only IPR (patents and printed publications, §§ 102/103) is available.
3. § 325(d) and Director-stage discretion. The Board's current practice is to scrutinize petitions that recycle art already before the examiner. The '883 patent's face cites 37–43 references, most notably the Omnitherm family (US 7,766,077; US 7,866,380; US 2006/0260788; US 2007/0261823), the Leader Energy flameless patents (US 7,424,916; US 7,637,232; US 2006/0185621), Multitek's flameless applications (US 2014/0174691; CA 2,811,829), US 9,228,760 (MAC, Inc.), and US 8,469,283 (Ventech). Art already of record invites a § 325(d) discretionary denial, so a viable petition should lead with new art, or with a materially different mapping of the old art, and should expressly address the Becton, Dickinson factors.

Recommended next steps

1. Do not build a defense on the assumption that this patent has been weakened. It has not been. There is no FWD to link to, no canceled claim to quote, and no PTAB disposition that helps you. If a demand letter or complaint asserts US 11,274,883, the patent comes at you at full strength.
2. Confirm the null result at the docket level before relying on it. Pull the PTAB E2E docket (https://developer.uspto.gov/ptab-api or the PTAB E2E UI) for patent number 11274883 and for application 16/452,177, and run a PACER/CAFC docket check on ConleyMax Inc. This is a 30-minute task and it converts my "not found" into a defensible "none." CourtListener (https://www.courtlistener.com) is the right free tool for the CAFC side; the Google Patents page (https://patents.google.com/patent/[US11274883B2](/patent/US11274883B2)/en) is the right starting point but explicitly is not a litigation docket.
3. If IPR is on the table, run the § 315(b) calendar first. The one-year bar from service is the single most common way a good invalidity case becomes an unavailable one.
4. Map the family before choosing a target. Assertion of the '883 method claims is only one of four live fronts (US 10,408,548, US 11,274,883, US 11,874,069, and pending US 2024/0133638). An IPR on '883 does not estop you as to the siblings, but because no estoppel has attached anywhere yet, all four remain open — and the pending continuation means the owner retains the ability to keep drafting claims while you litigate.
5. Start from the prosecution record, not from a blank page. The 19 non-patent citations and the examiner's 37–43 references give you a map of what the examiner has already seen (a § 325(d) hazard) and, by implication, where new art must come from.
6. Treat the litigation-status question as open, not as answered. I found no CAFC case, no IPR/PGR/CBM, and no confirmable district-court action involving this patent. Absence of evidence in public databases is not a representation that no litigation exists — if you are a defendant, your own service papers are the authoritative answer, and the earlier-generated summary in this file reached the same conclusion.

I'll verify the assignment record against USPTO Assignment Center and related sources before writing up.

Ownership Chain Reconstruction — U.S. Patent No. 11,274,883 B2

Source limitation up front: assignmentcenter.uspto.gov is a JavaScript application that does not return usable results to text-based retrieval. I could not open the Assignment Abstract of Title page for this patent directly. Everything below is reconstructed from (a) the USPTO assignment record mirrored in the Google Patents legal-events table for US 11,274,883 — which supplies the reel/frame, conveyance text, effective date, and recording date — and (b) independent verification of the assignee and inventors. I could not retrieve the correspondent-of-record block for reel 049587/0967, and I flag that gap rather than guess at it. Searches for other recordings (security agreements, name changes, corrective assignments) returned nothing, so treat the "every recorded assignment" list below as what the records I could reach show, not as a certified abstract.

Inventors

Pattern check — inventor retention: No departure signal. Both inventors remained with the assignee well beyond 12 months. Bell and Beckie are still named inventors on ConleyMax's most recent grants, including US 12,196,155 B2 ("Flameless combo heater," filed 2021-12-15, granted 2025-01-14) — roughly 12 years after the 2013 priority date. Same two inventors also appear on the design patent US D873,864 S ("Grain drying adapter," filed 2017-03-29) assigned to ConleyMax. This is the opposite of the pre-fire-sale signature you asked me to flag: the inventive team never left.

Minor note: public company profiles list Kevin R. Baker as ConleyMax's other co-founder alongside Bell. Baker is not a named inventor on this patent; the "all inventors departed" and "founder/inventor mismatch" checks are not triggered, but his absence from the patent is worth a line in the file.

Original assignee

• Entity named on the issued patent: ConleyMax Inc., Calgary, Alberta, Canada (Google Patents lists Original Assignee and Current Assignee as the same entity).
• Primary line of business: Operating company. ConleyMax "manufactures heating equipment. It provides flameless air, water, glycol, grain drying and combination air and glycol heaters for purchase and rental." Its USPTO trademark record (CONLEYMAX, first used 2013) covers portable flameless air/water heating machines for industrial and commercial use. Primary CPC concentration is F24H (fluid heaters) — exactly the product class its patents cover.
• Product embodying the claims: Yes. The specification itself describes a trailer/truck/skid-mounted flameless glycol heater with a stated ~1.2 M Btu capability, and the company's stated business is selling and renting precisely that equipment. This is a commercial-embodiment assignee, not a paper owner.
• Entity size / status: Listed as a small entity in the USPTO record (entity-status events 2019-06-25 and 2019-07-03). Still active — 4th-year maintenance fee paid 2025-09-09 (event M2551, small entity), and the portfolio shows grants through 2025. No bankruptcy, dissolution, or acquisition surfaced.
• Portfolio scale: third-party aggregators (PatentsView/PlainPatent, OnScope/Patsnap) put ConleyMax at roughly 15–37 US granted patents depending on counting method, across ~12 CPC subclasses. Small, focused, operating filer.

Assignment timeline

One recorded assignment exists in the chain I could reach.

• 2013-09-24 (executed / effective) / recorded 2019-06-25 — Reel 049587/0967
  • Conveyance: ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS)
  • Assignor: BELL, PATRICK; BECKIE, WILLIAM (individuals)
  • Assignee: CONLEYMAX INC., Canada
  • Correspondent: Not retrievable. The Google Patents legal-events mirror does not expose the correspondence block, and I could not query Assignment Center's abstract-of-title API. I therefore cannot report the attorney/firm of record on this recording. For completeness, the prosecution agent of record (a different field from the recording correspondent) is HEA Law PLLC, which recurs across the ConleyMax patent family — but a prosecution agent is not evidence of an NPE recording practice, and I am not treating it as such.
  • Context: Original founder-to-company assignment — not a fire-sale, not an internal reorg, not a transfer-to-asserter. Note the date relationship: the document was executed 2013-09-24, one day before the parent application 14/037,123 was filed (2013-09-25), and it was recorded 2019-06-25, the same day the continuation-at-issue (16/452,177) was filed. The cleanest reading is that the assignment covering the invention was re-recorded/wired against the new continuation on the day that continuation was filed.

What I did not find (explicitly):

• No second assignment, no assignment to any "IP Holdings / Licensing / Ventures" entity.
• No security agreement, no merger, no change of name, no corrective assignment, no release.
• No assignment involving any entity other than ConleyMax Inc. on either side of the chain.
• Caveat: I could not verify whether a separate, earlier 2013-dated recording exists against parent application 14/037,123 under a different reel/frame (a 2013 reel would be in the ~0150xx–0170xx range, not 049587). The 049587/0967 reel number is consistent with a 2019 recording. If an earlier 2013 recording exists, it does not change the ownership conclusion — it would be the same assignee — but it would change the "when was it first recorded" narrative. This is the one open item in the chain.

Timeline diagram

timeline
    title Ownership of US 11274883
    2013 : Inventors execute assignment to ConleyMax
         : Parent application 14 037 123 filed
    2019 : Continuation 16 452 177 filed
         : Assignment recorded reel 049587/0967
    2022 : Patent US 11274883 B2 issued
    2025 : 4th year maintenance fee paid

NPE / troll-pattern signals

Guardrail preserved from prior sections: the bare string "11274883" keeps returning UK company MAKOIL GROUP LTD (company number 11274883) and a Brazilian JUCISRS registration number 11274883. Neither is this patent; neither appears in this chain. Not merged.

Verdict

Operating-company assertion.

Justification: The entire recorded chain is a single assignment — reel 049587/0967, executed 2013-09-24 and recorded 2019-06-25 — conveying the invention from inventors Patrick G. Bell and William N. Beckie directly to ConleyMax Inc., and no subsequent transfer exists. ConleyMax is a Calgary manufacturer that sells and rents flameless air/water/glycol heaters — the exact product embodying claims 1–11 — files in CPC F24H (fluid heaters), is a small-entity filer, paid its 4th-year maintenance fee on 2025-09-09, and retains both original inventors on patents granted as recently as 2025-01-14 (US 12,196,155 B2). There is no shell LLC, no known asserter, no cascade, and no fire-sale.

One honest caveat on the label: the taxonomy's "Operating-company assertion" branch presupposes active enforcement against competitors, and the earlier sections of this file found no litigation or PTAB activity involving this patent. So read the verdict as "clean operating-company ownership, assertion prong unverified" rather than as evidence that ConleyMax is currently suing anyone. The ownership-chain question you asked — is this an NPE/troll structure? — is answered no.

Verify at: https://assignmentcenter.uspto.gov/ (search patent 11274883) or the legacy index https://assignment.uspto.gov/patent/index.html. Ask specifically for the abstract of title and the correspondence data for reel 049587/0967, and for any 2013-dated recording against application 14/037,123 — that is the only unresolved cell in this table.

I'll verify the patent record and its cited prior art against USPTO and public databases.

Let me verify the two most legally significant references — the Hebert reference cited as "X" in the family's PCT search report, and the Multitek reference.

Prior-Art Analysis — U.S. Patent No. 11,274,883 B2 ("Flameless glycol heater")

1. Patent identification (USPTO record — verified)

The record located under the number 11274883 matches the patent already summarized earlier in this file; I am not re-stating the bibliographic block. The points that drive the prior-art analysis below:

No contradiction with the previously generated sections was found; my independent checks confirm the same number, assignee, claim count, and family (parent US 10,408,548 B2; later US 11,874,069 B2 and pending US 2024/0133638 A1).

2. The § 102 date rule that controls this whole analysis

Because the '883 patent is a post-AIA patent with an effective filing date of 2013-09-25, the following references that published after the priority date are still potential § 102 art — but only under § 102(a)(2) ("secret prior art"), by virtue of their earlier effective filing dates:

All other cited references published before 2013-09-25 and are § 102(a)(1) art.

Claim-1 gist for mapping (from the issued claim, unchanged from the earlier section): (a) fluid pumped in a first closed circulation path; (b) heat transferred from a heating fluid in a second closed circulation path via a first heat exchanger sitting in both paths; (c) heat from the prime mover output transferred to the fluid via at least one second heat exchanger; (d) heat transferred from the fluid to the material via a third heat exchanger in the first path; (e) wherein a dynamic heat generator is arranged in the second path. Dependents add: pump-to-reservoir (2), pump in heat generator (3), glycol (4), oil (5), water (6), coolant+exhaust output (7), coolant exchanger (8), exhaust exchanger (9), air-to-fluid pipe exchanger w/ exhaust crossflow (10), 20–25 °C exhaust (11).

3. Complete cited-reference table (all 43 references of record)

Rating key: [A] strong single-reference § 102 candidate against claim 1 · [B] on-point for claim 1, needs one or more limitations supplied · [C] background / sub-component only · [D] tangential.

Related but not of record in '883 (appears in the siblings' lists, worth flagging because of the family overlap): US 2014/0209281 A1 (Multitek, filed 2013-01-30 → § 102(a)(2) art, same disclosure family as #35) and US 9,802,459 B2 (granted version of #35's family). These are effectively the same prior-art teaching as reference #35 and should be treated together.

4. The references that actually matter — deep dive

4.1 US 2011/0005757 A1 (Hebert) — the single most dangerous reference

Full citation: Hebert, Jeff; "Device and method for flowing back wellbore fluids"; US 2011/0005757 A1; published 2011-01-13; priority 2010-03-01. § 102(a)(1) art.

Why it is the top § 102 candidate: the reference discloses exactly the two-fluid architecture of claim 1. In its FIG. 2/FIG. 3 embodiments, a centrifugal pump moves the fluid to be heated through a hydraulic-oil exchanger — where the oil "is pumped by a hydraulic oil pump, which shears the oil and increases the temperature in the oil," i.e., a dynamic (shear) heat generator — and then through an engine-exhaust heat exchanger and/or an engine-coolant (water) heat exchanger, all "without the aid of an open or enclosed flame." The oil circulates from a holding tank through the hydraulic oil pump (heat generator) and the oil exchanger and back, i.e., a second closed loop; the oil exchanger is in both loops. That is the literal core of claim 1.

• Potentially anticipates: claim 1 (all elements in the FIG. 3 circulating-fluid embodiment), and claims 3, 4, 5, 6, 9; claim 7 (output = coolant + exhaust) in the FIG. 1/embodiment that retains the water exchanger; claims 10–11 to the extent its exhaust exchanger uses a tube/coil arrangement with cooled exhaust discharge.
• Weak spot for the patentee: Hebert's FIG. 2 deliberately removes the water exchanger to reach higher temperatures "without overheating the engine," so a defense mapping claim 8 (coolant HX) to Hebert must use the FIG. 1 embodiment.
• Corroboration: the Canadian ISA (CIPO) cited Hebert as category "X" against the parent family's PCT claims — the strongest single-piece signal of anticipation in the file.

4.2 US 2014/0174691 A1 (Kamps / Multitek) — the closest structural match

Full citation: Kamps, Douglas; Stolar, Timothy C.; Umlauf, Thomas J.; "Self-Contained Flameless Fluid Heating System"; US 2014/0174691 A1; published 2014-06-26; application US 13/723,767 filed 2012-12-21. Available under § 102(a)(2) (effectively filed before 2013-09-25).

It discloses: an internal-combustion engine; a heat generator having "a shaft … driven by a rotatable crankshaft … and a rotor … such that heat transfer fluid is received and circulated in the housing by means of the rotation of the rotor" (a dynamic/friction heat generator); a heat transfer fluid reservoir and charge pump; a heat transfer fluid heat exchanger that transfers heat from the heated transfer fluid to the supply fluid (a heat exchanger shared between the HTF loop and the supply-fluid path — claim 1 element (b)); CAC/charged-air intercooler HX, engine coolant HX, and exhaust HX (claims 7, 8, 9; the CAC maps to the "intercooler" recited in the sibling '548 claim 1); and "discharge of the cooled exhaust gas to the atmosphere" (claims 10–11).

• Potentially anticipates: claims 1, 2, 3, 4, 5, 7, 8, 9 — and 10 (air-to-fluid HX with exhaust crossflow), with 11 (20–25 °C exhaust) depending on whether the reference's cooling numbers are read to meet that range.
• The ISA itself marked this reference "X,P" (anticipatory) against all of the parent PCT's claims 1–20, so it is a genuine, examiner-recognized anticipation candidate — not a mere background citation.

4.3 The flameless-family core: US 9,228,760 B2 (MAC), US 7,424,916 B2 / 7,637,232 B2 (Leader Energy "hot oiler"/"boiler"), and the Omnitherm set (US 2006/0260788; 2007/0261823; 7,766,077; 7,866,380; 2011/0079561)

These five families all disclose the same genus the '883 patent claims: engine-driven heat generation plus recovery of engine waste heat, transferred through heat exchangers to a working fluid, with no open flame. Any of them can be paired with an ordinary-skills showing to attack dependent claims, and each is a moderate standalone candidate against claim 1. US 9,228,760 B2 (MAC, filed 2012-04-27) and US 7,424,916 B2 (Leader Energy "Flameless hot oiler") are the strongest of this group because they are engine-driven and liquid-fluid directed at a wellsite, matching the '883 field of use.

4.4 Single-element references (attack only specific dependents)

• US 8,469,283 B2 (Ventech, liquid heat generator w/ integral HX) and US 2013/0270352 A1 (BorgWarner viscous coolant heater) → the "dynamic heat generator" limitation of claim 1.
• US 2005/0121532 A1 (Reale, intercooled gas turbine) and US 2011/0185713 A1 (Koopmann, air heater) → the intercooler / engine-output-heat limitations of claims 1, 7, 8.
• US 3,231,016 A (heat-recovery silencer) → exhaust-heat-capture limitations of claims 10–11.
• US 2004/0144200 A1 (Giordano, torsional damper coupling) → does not read on any of claims 1–11 of the '883 patent; the "torsional vibration dampener" appears only in the specification and in the sibling '548 claims. Do not use it against the '883 claims.

5. Bottom line and caveats

1. The two references to lead with are US 2011/0005757 A1 (Hebert) and US 2014/0174691 A1 (Multitek/Kamps). Both were affirmatively cited by the ISA as category "X" (anticipatory) against the ConleyMax family's PCT claims, and both independently disclose the two-closed-loop + shared-heat-exchanger + dynamic-heat-generator structure of '883 claim 1. Hebert is § 102(a)(1) art; Multitek is § 102(a)(2) art.
2. Secondary § 102 candidates against claim 1: US 9,228,760 B2 (MAC), US 7,424,916 B2 and 7,637,232 B2 (Leader Energy), and the Omnitherm set (US 2006/0260788 A1; US 2007/0261823 A1; US 7,766,077 B2; US 7,866,380 B2; US 2011/0079561 A1).
3. Reality check that must accompany any § 102 claim: every one of these references was of record before the examiner at some point in the family, and the '883 claims nonetheless issued over them. That does not defeat a § 102 theory, but it means any anticipation position must be built on an element-by-element mapping, not on the bare citation. It also flags a § 325(d) discretionary risk in any IPR built on art already of record.
4. Careful with CA 2,811,829 A1 — it is cited on the face of the patent but published (2014-07-30) after the '883 priority date and is a foreign document; it is not § 102 prior art against '883. Treat its US sibling (US 2014/0209281 A1, filed 2013-01-30) as the operative § 102(a)(2) reference.
5. Nothing above is a legal conclusion. "Potentially anticipates" is a screening judgment based on the reference disclosures as described in the record; a true § 102 analysis requires the element-by-element comparison against the issued claim language as construed under Phillips.
6. Contradiction check: no contradiction with the previously generated patent summary, litigation summary, or PTAB section. The earlier note that "the examiner has cited 37–43 references, including the Omnitherm, Leader Energy, Multitek, MAC, and Ventech families" is confirmed here at the individual-reference level.

I'll ground this analysis by pulling the disclosure content of the key prior-art references cited on the face of US 11,274,883, then map them to the claim elements.

Good grounding. Let me pull the Multitek and Omnitherm references plus the Leader flameless boiler, which are the closest art on the waste-heat-recovery and closed-loop elements.

Obviousness Analysis — U.S. Patent No. 11,274,883 B2 under 35 U.S.C. § 103

Building on the earlier sections of this file (claim structure, family, litigation, PTAB). I do not repeat the claim 1 summary from those sections; I cross-reference it.

0. Scope, sources, and one date flag

Governing law. The '883 application (16/452,177) is a continuation of 14/037,123, filed 2013-09-25 — after the AIA's March 16, 2013 effective date. So AIA §§ 102/103 apply, and the critical date is the 2013-09-25 priority date (cross-referenced in the PTAB section). Note the '883 issued 2022-03-15, so the PGR window closed ~2022-12-15; only IPR (patents and printed publications, §§ 102/103) remains available for a Board challenge. Every reference below must therefore have a § 102(a)(1) public-disclosure date, or a § 102(a)(2) effective filing date, before 2013-09-25.

What I verified from full text this session: US 7,424,916 B2 (Leader "Flameless hot oiler"), US 8,469,283 B2 (Ventech "Liquid heat generator with integral heat exchanger"), US 2012/0174987 A1 (Crawford "Flameless heating system"), US 2014/0174691 A1 / US 9,802,459 B2 (Multitek "Self-Contained Flameless Fluid Heating System") and its sibling US 2014/0209281 A1 / US 10,151,539 B2, US 9,228,760 B2 (MAC), and the Leader "Flameless boiler" abstract (US 7,637,232 family). What I am relying on from the citation record only — I did not retrieve full text: the Omnitherm family (US 7,766,077; US 7,866,380; US 2006/0260788; US 2007/0261823; US 2011/0079561), CA 2,741,507 (Thawzall), US 2011/0297353 (Stegeman, "Oilfield heat exchanger"), the Zwick flameless-deicer patents, and US 3,231,016 (heat recovery silencer). I flag each where used.

Date flag (no auto-correction): the task header states April 26, 2026; my system date is 2026-09-29. I have not reconciled these and they do not affect the analysis, which turns on the 2013-09-25 critical date.

1. Level of ordinary skill (Graham factor 1)

The PHOSITA here is a mechanical engineer (B.S. or equivalent) with roughly 2–5 years in mobile industrial fluid-heating systems, or a senior technician with substantially more hands-on experience, and is familiar with: closed-loop hydronic circuits; hydraulic/dynamic (shear or hydrodynamic) heat generation; heat-exchanger selection and sizing; and recovery of internal-combustion-engine waste heat from (i) engine coolant, (ii) charge-air/intercooler, and (iii) exhaust. The field is small, oilfield-adjacent, and highly concentrated — which matters for the "analogous art" and "motivation" steps.

2. Element-by-element mapping of claim 1

The important architectural point, which the '883 shares with the prior art rather than departing from it: claim 1 requires two closed loops joined by a shared heat exchanger — a first loop for an intermediate fluid (glycol), a second loop for a heating fluid (oil) containing a dynamic heat generator, engine waste heat dumped into the first loop, and a third exchanger dumping that loop's heat into the target material. Compare the apparatus claims of the parent, US 10,408,548 B2 (as reproduced at justia.com — first/second closed circulation paths, "first heat exchanger arranged in both").

Observation. No single reference I retrieved discloses every element in the specific arrangement of (c)+ (d) — i.e., all prime-mover waste heat routed into the same intermediate fluid that also receives the dynamic-generator heat, followed by a final delivery exchanger. That is the only genuine gap, and it is a gap of arrangement, not of component or principle. That is the classic § 103 posture, not a § 102 posture. (For completeness: the near-identical architecture later appears in Multitek's own US 10,844,766 / US 11,434,805 claims — "heater fluid in a closed loop including the heater fluid pump, a dynamic heater and a first heat exchanger" plus water routes heated by engine air/coolant/exhaust — which is independent corroboration that the arrangement was a known design objective in this field.)

3. Combinations that render claim 1 obvious

Combination I (strongest) — Multitek '4691/'459 in view of Leader '916

• Multitek '4691 supplies: flameless mobile prime-mover-driven heater; a dynamic heat generator (rotor mounted on the engine crankshaft, heating by fluid friction) in a heat-transfer-fluid loop with a reservoir and charge pump; a heat-transfer-fluid HEX transferring that heat to the supply fluid; and CAC, engine-coolant, and exhaust exchangers all delivering prime-mover waste heat to the same supply fluid; a main pump; trailer mounting.
• Leader '916 supplies: the closed heat-exchange loop of an oilfield flameless heater; the express teaching that the shear heat generator (water brake) is in that same closed loop ("The heat exchange fluid is used to load the water brake, and the shearing heat is transferred to the heat exchange fluid which is then used as an additional source of heat"), i.e., element (e); and a downstream exchanger delivering heat to a batch fluid — element (d) — in exactly the tank/well-service setting the '883 addresses.
• Motivation (KSR "known elements, predictable result" + "improvement of similar devices"): both references address the same problem (heating large fluid volumes at remote oil/gas sites with no open flame), in the same field, and Multitek states its own objective is "improvements … particularly with regard to efficiency." Recovering engine coolant and exhaust heat is the single most obvious efficiency lever in a prime-mover-driven heater — Leader already teaches it, and its own specification says the rig "can be optionally provided with additional bolt-on pumps," inviting modular additions. The combination does no more than arrange known heat sources in series on a common intermediate loop.
• Result: claim 1 obvious. Note that this is not a § 102 case only because no retrieved reference literally recites the "closed" character of the fluid path and a discrete third exchanger and the dynamic generator in a separate second loop simultaneously; the gap is a matter of how the loops are drawn.

Combination II — Leader '916 in view of Leader '232 and Multitek '4691

• '916 gives the flameless closed loop, the engine-coolant and exhaust HEXs, the batch-fluid HEX, and the water-brake shear generator.
• Leader '232 gives the clean two-path architecture in claim language: a shear heat generator driven by a prime mover, a supply reservoir for the generator fluid, and a first pump circulating that fluid from the reservoir to the generator — the "second closed circulation path" of '883 claim 1 — plus a pressure vessel receiving heated fluid downstream, which is the "third heat exchanger to the material" analog (heat delivered to a receiving body of fluid).
• Motivation: same assignee, same specification lineage and same stated purpose as '916 (flameless heating of well-service fluids), i.e., the strongest possible "suggestion in the prior art" — the second reference is the same inventor-entity's complementary disclosure of the shear-generator sub-system.

Combination III — Crawford '987 in view of Ventech '283 and Multitek '4691 (best for the "dynamic heat generator" limitation)

• Crawford '987 expressly discloses a "dynamic heat generator" (DHG) operatively connected to an internal combustion engine, a pump delivering fluid to the DHG, a first heater cross-exchanging combustion-cycle heat with the fluid before it enters the DHG, and a second heater cross-exchanging combustion-cycle heat with the heated stream produced by the DHG — the exact vocabulary of '883 claim 1 and of the parent '548.
• Ventech '283 supplies an express "liquid heat generator" (hydrodynamic heater) having an integral heat exchanger and rotor driven from the engine drive shaft — the structural anchor for "dynamic heat generator … with the first heat exchanger in both paths."
• Motivation: Crawford's stated purpose is replacing gas-fired/open-flame heating in oilfield and pipeline service; Ventech's stated purpose is supplementing insufficient engine-coolant heat — the very deficiency the '883 solves by stacking four heat sources.

Combination IV — for the waste-heat-recovery sub-system generically

Any of the above in view of one or more of: Omnitherm US 7,766,077 / US 7,866,380 / US 2006/0260788 / US 2007/0261823 ("Self-contained modular heater"; "producing hot water without a flame," 2005 filings); US 3,231,016 "Heat recovery silencer" (engine exhaust → heat recovery, 1966); Zwick US 5,098,036 / US 5,222,696 / US 5,190,249 (flameless deicer using engine heat); Reale US 2005/0121532 A1 (district heating with an intercooled engine, i.e., recovering charge-air heat); Thawzall CA 2,741,507 (flame-less heat); US 5,709,201 (Anser, heating a liquid medium). (These four I did not retrieve in full this session — treat the mapping as citation-record-level, not text-verified.)

4. Dependent claims 2–11

On claim 11. The claim recites a result achieved by sizing ("arranged and sized such that"). The '883 specification's own figure (exhaust in at 700 °F/400 °C, out at 70 °F/25 °C) is presented as an ordinary design outcome of a stainless-steel exhaust exchanger, not an unexpected result. Under In re Aller / In re Peterson and KSR, optimizing a result-effective variable (exchanger surface area / stack temperature) by routine engineering is obvious, particularly where multiple references already teach recovering exhaust heat down to a low stack temperature. Counter-arguments the owner will raise: (i) 20–25 °C is below the acid dew point of diesel exhaust, so achieving it presupposes a specific corrosion-resistant design (the spec's "stainless steel or similar non corrosive material"); (ii) the range is narrower than anything in the art. My assessment: this is a rebuttable position, not a strong one, because the claim language is structural-sizing plus result, and the '883 spec concedes the material choice as conventional. Note also that § 112(b) attack on a "result" limitation is unavailable in IPR — only §§ 102/103.

5. Why the PHOSITA would combine — consolidated motivation

1. Common problem, common field (analogous art). Every reference above is a mobile, flameless, prime-mover-driven industrial fluid heater, predominantly for oil/gas well sites. KSR's "familiar elements according to known methods."
2. Same regulatory driver. Multitek, Leader, MAC and Crawford all recite the same regulatory premise (no open flame in the immediate vicinity of the wellhead); Leader additionally notes the safe-distance penalty of open-flame units. That is a market/policy "design incentive" under KSR.
3. Efficiency is the stated objective. MAC: "improvements in flameless heater technology are desired, particularly with regard to efficiency." Multitek: improvements "highly desirable." The '883's contribution — stacking four heat sources onto one intermediate loop — is the straightforward way to raise output (~1.2 MMBtu) per unit of engine fuel.
4. Predictable result, no new principle of operation. Each added heat exchanger is a known device performing its known function (liquid–liquid, air–liquid) at a known point in a known loop; the combination is a series arrangement, not a re-architecture.
5. "Obvious to try." Where the number and placement of waste-heat recovery stages is the only open design variable, a finite number of predictable options exist, and the art teaches the expected benefit of each.
6. Same-inventor/complementary disclosures. Combination II relies on two Leader Energy publications describing two halves of the same system in the same specification family — the clearest possible "suggestion."

6. Anticipation vs. obviousness, and the § 325(d) hazard

• No clean § 102 case on the retrieved art. The one limitation that consistently resists literal reading is the paired requirement of (i) a closed path for the fluid that receives both the dynamic-generator heat (via the heating fluid) and the prime-mover waste heat, and (ii) a third exchanger in that same path. Multitek '4691 delivers (i) but not a discrete (ii); Leader '916 delivers a two-loop/third-exchanger arrangement but routes engine waste heat to the other loop.
• The defense should therefore be built as § 103, not § 102.
• § 325(d) caution (cross-reference the PTAB section of this file). The '883 file already carries 37–43 references, including every reference named above. A petition that re-runs Multitek/Leader/Crawford/Omnitherm as the primary mapping invites discretionary denial under § 325(d) (Becton, Dickinson factors). A viable IPR should lead with new art, or with a materially different mapping of the of-record art (e.g., using Ventech '283's hydrodynamic-heater structure as the primary "dynamic heat generator" anchor, which the examiner cited only as a secondary reference in the '548 family).
• Estoppel: none attaches; per the earlier section, no AIA trial has ever been instituted against this patent or its siblings.

7. Strength ranking and bottom line

Bottom line. Claim 1 of US 11,274,883 is, on the retrieved art, a predictable series-arrangement of known flameless-heater subsystems — an engine-driven dynamic heat generator in a closed intermediate loop, engine coolant/intercooler/exhaust heat recovery, and a shared liquid–liquid exchanger coupling that loop to the delivered fluid — all of which were individually and (in pairs) collectively disclosed before 2013-09-25 by Multitek, Leader Energy, Crawford, Ventech and Omnitherm. The strongest single attack is Multitek US 2014/0174691 A1 (US 9,802,459 B2) in view of Leader Energy US 7,424,916 B2, with Leader US 7,637,232 B2 and Ventech US 8,469,283 B2 as reinforcing secondary references. The only limitation with meaningful defensive value is claim 11's 20–25 °C exhaust-output range, and even that is a result-of-sizing limitation vulnerable to In re Aller-type reasoning — though it is immune to a § 112 counterattack in an IPR. Expect any real challenge to fail not on the merits of the art but on § 325(d) discretion, because the examiner has already seen and allowed over most of this art.

Sources

• US 11,274,883 B2 — https://patents.google.com/patent/[US11274883B2](/patent/US11274883B2)/en
• Leader Energy US 7,424,916 B2 (full text) — https://patentimages.storage.googleapis.com/89/a6/35/98a5b4e852509d/US7424916.pdf · https://patents.justia.com/patent/7424916
• Leader Energy portfolio (flameless boiler / shear generator abstract) — https://patents.justia.com/assignee/leader-energy-services-ltd
• Ventech US 8,469,283 B2 — https://patents.google.com/patent/US8469283B2 · https://patentimages.storage.googleapis.com/bd/d0/8c/d96482e1631002/US8469283.pdf
• Multitek US 2014/0174691 A1 / US 9,802,459 B2 — https://patents.google.com/patent/US20140174691A1 · https://patentimages.storage.googleapis.com/d2/94/f1/7fb4694aac95fa/US9802459.pdf
• Multitek US 2014/0209281 A1 / US 10,151,539 B2 — https://www.freepatentsonline.com/y2014/0209281.html
• Crawford US 2012/0174987 A1 — https://patents.google.com/patent/US20120174987A1
• MAC US 9,228,760 B2 — https://patents.google.com/patent/US9228760
• Parent US 10,408,548 B2 claims — https://patents.justia.com/patent/[10408548](/patent/10408548)