US 1118278

I'll ground this summary in both the authoritative patent text and targeted searches for the identifier.

Identification and scope check

I treated 1118278 literally as the US patent number US 1,118,278 A (seven digits, i.e., 1,118,278 — a 1914 grant, not an "11,182,78x" style modern number). A bare "1118278" also collides with unrelated documents — e.g., EP 1118278 A2/A3 ("Mask") and a Chinese publication 1118278 (a 1995 extraction/concentration apparatus, per 食品伙伴网) — so those were excluded. Corroborating hit: Justia's reference table for US 12,145,113 lists "1118278 | November 1914 | Greathead," matching the 1914 grant.

On the litigation search: I found no CAFC 2026 docket, IPR, ITC action, or any live proceeding involving 1,118,278. That is expected: the patent's stated term expired 1931-11-24, ~95 years ago, and Google Patents lists its status as "Expired – Lifetime." My searches surfaced only unrelated oil-burner litigation (e.g., a 1919 Ninth Circuit appeal in Stafford v. Albers Bros. concerning Stafford patent 860,418, not this patent) — I am not asserting any connection. I found no 2026 activity of any kind.

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Bibliographic summary (from the patent text on Google Patents)

Abstract

There is no formal abstract. Abstracts were not a US patent requirement in 1914, and this document has none. The functional equivalent is the stated object:

"the object of the invention being to provide a burner which will be self-regulating as regards the amount of steam and oil supplied to the burner and will also burn without smoke."

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Plain-language overview of the independent claims

All seven claims are independent in form (none recites dependency on an earlier claim), which is typical of pre-1930s drafting. Claims 2–7 are all apparatus claims built on the same core structure. Note some antecedent-basis quirks that appear to be drafting/printing errors: claim 2 refers to "said oil chamber" and claim 3 to "said wall" without a prior recital (claim 3 also prints "an an deflector" — an obvious typo).

Underlying hardware (from the specification, useful for reading the claims): main casting 1 with base 2 and burner portion 3; steam conduit 4/steam pipe 6; threaded cylindrical wall 9 forming annular steam chamber 11 with the burner-portion wall; narrow annular steam outlet 12; flange 13; valve chamber 14 containing annular steam valve ring 16 with passages 18 registering with steam ports 17; coaxial cylindrical wall 19 with radial guide ribs 21 dividing the annulus into longitudinal compartments 22; oil chamber 23 fed by conduit 24/oil pipe 26; chamber 27 leading to conical annular oil outlet 28 (the oil valve); head 29 with air holes 66; brass diaphragm 32 clamping wall 19 (closure for oil chamber 23); cylinder 33 with air chamber 67 vented by holes 68; tube 40; a second diaphragm 36 forming a movable wall of steam chamber 49 fed by steam pipe 51, opposed by coiled spring (52 in the text); rod 52 with hand wheel 56 carrying air guide 57/ribs 58 and deflector 29′ (Fig. 1) or perforated disks 62, 61 on tubes 63 (Fig. 4), forming conical annular air outlet 61; valve-actuating stems 72 with disks 74 engaging spur ring 76 driven by worm 77 on shaft 78 (handle 82), the ring being screwed on threaded portion 83 of wall 19; clean-out steam pipes 69 (air) and 71 (oil).

1. Claim 1 — the pressure-regulating steam valve. An oil conduit surrounded by an annular steam chamber; a circular series of steam ports leading from the steam supply into that chamber; a valve ring encircling the series of ports and having its own circular series of holes that can register with the ports; a diaphragm moved by the supply steam pressure; a linkage between diaphragm and valve ring such that rising steam pressure contracts the port openings and falling pressure enlarges them (self-regulation); plus hand adjustment of that linkage to set how far the ports open. (Embodied by ring 16/ports 17/passages 18/diaphragm 36/stems 72/spur ring 76/worm 77.)

2. Claim 2 — burner with sliding oil-valve wall. An annular steam chamber; a tubular wall guided inside and spaced from a wall of the steam chamber so the two together define the oil conduit; an oil valve connected to that tubular wall; a diaphragm secured to the wall's inner end that movably supports it; an air chamber on the far side of that diaphragm from the oil side; an apertured head at one end of the wall communicating with the air chamber (air admitted to the wall's interior); an air deflector at the other end, inside the oil valve; and a second diaphragm connected to the wall and forming a movable wall of a steam chamber, so steam pressure shifts the wall lengthwise.

3. Claim 3 — same combination, differently worded. Substantially the claim-2 combination (oil valve on the wall; diaphragm at the wall's inner end supporting it movably; air chamber on the opposite side; apertured head communicating with the air chamber; air deflector inside the oil valve; steam-pressure diaphragm forming a movable wall of a steam chamber) recast with narrower phrasing rather than expressed in terms of an "annular steam chamber." As printed it lacks an antecedent for "said wall."

4. Claim 4 — adds the oil-chamber diaphragm closure. The claim-2/3 combination, with the added limitation that the first diaphragm also forms a movable wall of the oil chamber (so the oil chamber is closed at its inner end while the wall still floats freely without friction), in addition to the air chamber, apertured head, air deflector, and steam-pressure diaphragm moving the wall longitudinally.

5. Claim 5 — adds independent wall adjustment. The claim-4 combination plus means for independently moving the wall — i.e., the hand-wheel/rod arrangement allowing the oil valve setting to be changed by hand independently of the automatic steam-pressure action.

6. Claim 6 — adds independent steam-passage adjustment. The claim-4 combination plus means for independently varying the size of the steam passage to the burner — i.e., the worm 77 / spur ring 76 / stems 72 mechanism varying registry of passages 18 with ports 17.

7. Claim 7 — adds air-deflector adjustment. The claim-4 combination plus means for adjusting the air deflector within the oil valve — i.e., rod 52 and hand wheel 56 setting the deflector (or, in the Fig. 4 form, the perforated disks) to control the air blast.

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Stated operation (for context)

The specification states the burner is self-regulating: when boiler steam pressure falls, pressure on diaphragm 36 falls, spring (52) presses it inward, enlarging the oil outlet, while registry of passages 18 with ports 17 increases, increasing steam supply — raising the fire and restoring pressure; excessive pressure does the reverse. Oil, steam, and air can each be varied independently, and each valve (plus the clean-out jets 69, 71) can be adjusted while the burner is running. The patent asserts that oil fed by gravity and cold retains its volatile gases until drawn out by steam suction at the nozzle, giving complete combustion, oil savings, and "an utter absence of smoke."

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Related-art context (as listed on Google Patents)

• Cited by, among others: US 2,479,166 (La Velle, "Oil burner with steam cleaning means," 1949); US 2,655,986 (Inland Steel, 1953); US 3,652,017 (Nielsen & Sons, 1972); US 4,544,095 (Boliden, 1985); and a set of Cirkul, Inc. additive-cartridge patents/applications (US 2021/0252464; US 12,157,096; US 12,145,113/114; US 12,329,307; US 12,342,954; US 12,408,789; US 12,557,932) — the Cirkul citation appears to be a background/listing reference rather than substantive prior art of the same field, though I cannot fully verify the citation context from the sources retrieved.
• Similar documents listed include US 721,900; US 736,473; US 733,579; US 776,847; US 928,497; US 1,020,348; US 1,036,758; US 1,057,868; US 1,073,936; US 1,107,614; US 1,131,480; US 1,150,461; US 1,169,091; US 1,189,992; US 1,232,921; US 1,434,238; US 2,042,034; US 2,117,388.

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Uncertainty / caveats

• Assignee: Google Patents reports "Individual" with no corporate assignee; I have not verified assignment records in USPTO Assignment, so I cannot say whether the patent was ever assigned during its term.
• OCR/reference-numeral inconsistencies in the source: the fetched text contains garbles and duplicate numerals (e.g., "hand wheel ll," "bearing 5a," numeral 52 used for both a spring and a rod, "deflector '29," "stuifing"/"Goaxially"). I have reported these as printed rather than correcting them, per the literal-interpretation rule; exact figure-part correspondence for those items is therefore not certain.
• No formal abstract exists; the object statement quoted above is the closest equivalent and is not an official abstract.
• No 2026 CAFC or other live proceeding exists for this number; any statement of current legal status is the source's own disclaimer (Google Patents notes its legal-status data is an assumption, not a legal conclusion). Expiration on 1931-11-24 reflects the 17-year term then in effect.
• The specification is a pre-1952 US patent and was not examined against modern §112/§101 standards; claim form (all independent, with some antecedent gaps) reflects 1914 practice.

I'll search for litigation involving US patent 1118278 across patent litigation databases.

Let me run additional targeted searches to be thorough.

Result: No litigation found involving U.S. Patent No. 1,118,278

I searched patent-litigation resources (Unified Patents litigation portal, PACER/CourtListener-derived materials, Federal Circuit and district court opinions, PTAB records, and general web sources) for the specific number 1,118,278 / US1118278. I found no case — district court, ITC, PTAB, or Federal Circuit — in which U.S. Patent No. 1,118,278 was asserted, challenged, or otherwise at issue.

Why this result is expected

Per the authoritative patent record (Google Patents, fetched 2026-09-27):

The patent expired November 24, 1931 (17 years from grant, the term then in effect). It has therefore been unenforceable for roughly 95 years, which is fully consistent with the absence of any infringement action. Two further structural reasons: the record shows an individual inventor/original assignee with no recorded assignments (no corporate successor to sue or be sued), and the claimed subject matter (an annular steam chamber with a pressure-responsive diaphragm valve for atomizing oil) sits in a technology area that was largely superseded.

Important — do NOT confuse these with US 1,118,278

My searches returned multiple hits on different patents whose numbers merely end in "827." None of the following involve U.S. Patent No. 1,118,278, and none should be attributed to it:

• US 11,332,178 — Hong Kong Uking Trading Ltd. v. Zhejiang Hengfeng TOP Leisure Co., S.D. Fla., No. 8:26-cv-02635 (complaint filed 2026-09-10), a declaratory-judgment/APEX dispute over a foldable hand cart. This is a different, modern patent (note the additional digits).
• US 8,032,278 — Verizon Connect Inc. v. Omega Patents, LLC, IPR2023-01162, and Geotab USA, Inc. v. Omega Patents, LLC, IPR2023-00504 (plus related district court litigation and ex parte reexaminations). Different patent.
• The '827 patent in Medichem v. Rolabo (Fed. Cir. 2002-1461, Dec. 23, 2003) — a chemical-process patent in an interference/non-infringement dispute. Different patent.
• The '278 patent in Fortinet, Inc. v. Forescout Techs. (N.D. Cal.) — network-access-control compliance patent. Different patent.
• The '278 patent in CollegeNET, Inc. v. ApplyYourself, Inc. (D. Or., 3:02-cv-01359) and in Axsome Therapeutics, Inc. v. Apotex Inc. (D.N.J., 2:25-cv-16038) — all different patents.
• The '827 patent in IPR2026-00109 (Apple Inc. v. HBCU Messaging US LP) — a cellular messaging patent. Different patent.

Similarly, contemporaneous 1920s oil-burner litigation that surfaced in the search — Hardinge Bros. v. Marr Oil Heat Mach. Corp., 27 F.2d 779 (7th Cir. 1928) (King patent No. 1,158,058), and Ray v. Bunting Iron Works (N.D. Cal., In Equity No. 689, 1924, involving Ray patents Nos. 1,193,819 and 1,285,376) — concerns entirely different patents and parties. I found no indication that Greathead's 1,118,278 was ever asserted in those or any other suits.

Caveats on confidence

• High confidence that no litigation is recorded in the modern, searchable databases. Pre-1930s litigation records are not comprehensively digitized, so an unrecorded, short-lived, or unpublished 1914–1931 suit cannot be ruled out absolutely. However, a suit would have had to be filed within the patent's enforceability window (1914–1931), which predates the digitized dockets now available.
• The patent's "Cited By" list (e.g., US 2,479,166; US 2,656,986; US 3,652,017) reflects citation in later prosecution, not litigation.
• Per operating rules, I have interpreted the number literally as 1,118,278 and have not substituted the visually similar modern numbers above for it.

Bottom line: No known litigation involves U.S. Patent No. 1,118,278. I found no plaintiff, defendant, jurisdiction, case number, filing date, or outcome to report, because no such case appears to exist.

I'll verify the structured data with a quick check before reporting.

Proceedings overview

Zero AIA trial proceedings on file. The structured "PTAB proceedings on file" block (USPTO ODP) returns no IPR, PGR, or CBM petitions against US 1118278; my independent web checks surfaced no PTAB docket, no Final Written Decision, and no Federal Circuit appeal that the ODP ingest would have missed. For a defendant today the posture is not "hardened patent" or "invalidated patent" — it is expired patent: US 1118278 granted 1914-11-24 and its term expired 1931-11-24 (Google Patents legal status: "Expired – Lifetime"; "Anticipated expiration 1931-11-24"), over 94 years ago. There are no claims to invalidate, no live term to infringe, and no damages exposure on this patent.

Because there are no proceedings, I am not generating per-proceeding sections — writing them would require fabricating numbers, panels, and dispositions, which the constraints forbid.

What I checked (and what I found)

False-positive traps to avoid (identifiers must be read literally, and the same number string exists in other offices):

• EP 1118278 A2 ("Mask", Milliken & Co. family, published 2001-07-25) — a completely different, unrelated European publication. Not this patent, and not a proceeding.
• CN 1118278 (Chinese publication, 1996) — likewise unrelated.
• The "Cited By" table on the Google Patents page (US2479166, US2655986, US3652017, US4544095, and the modern Cirkul, Inc. family — US20210252464A1, US12145113, US12145114, US12157096, US12329307, US12342954, US12408789, US12557932) is a patent-citation list. Cirkul citing a 1914 burner patent as art in its additive-cartridge applications is a citation signal, not an AIA trial involving US1118278.

Strategic summary

Claim status of US 1118278: none are canceled, none are sustained in any AIA trial — all seven claims are simply moot. Claims 1–7 were never tested at the PTAB because no petition was ever filed. The reason is obvious on the face of the document: the 17-year term ran from grant on 1914-11-24 to expiration on 1931-11-24. There is no enforceable claim, no maintenance-fee lapse issue to litigate, and no reexamination or AIA trial history. Any assertion of this patent today is a historical curiosity or a citation in an infringement chart, not a live cause of action — statutory damages and injunctions require an unexpired term.

Estoppel landscape: not applicable. 35 U.S.C. § 315(e)(2) estoppel attaches to a petitioner that obtains an institution decision. With no petitioner, no institution, and no FWD, there is no estoppel on any ground and no prior-art ground is "used up." Conversely, there is also nothing to gain: the § 315(b) one-year bar, § 325(d) discretionary denial, and Fintiv considerations are all irrelevant because the patent cannot support a live infringement suit in the first place. (Note also the statutory gatekeeping provisions: PGR requires an effective filing date on or after 2013-03-16, and CBM review sunset on 2020-09-16 — neither could reach a 1913-filed, 1914-granted patent in any event.)

Pattern signals. No repeat petitioner, no patent-owner appeal activity (Robert G. Greathead, of Vallejo, California, is long deceased and the patent shows assignee "Individual"), and no defensive aggregator such as Unified Patents anywhere in the chain. The absence of PTAB activity here is not the usual "well-asserted patents attract IPRs" signal — it simply reflects a patent that has been in the public domain for nearly a century. The only modern relevance is as § 102(a)/§ 103 prior art in other people's prosecutions (e.g., the Cirkul citations noted above). If a demand letter cites US 1118278 against your product, that is itself evidence the letter is not competently drafted.

Recommended next steps

1. If you are a defendant and a demand letter, complaint, or infringement chart cites US 1118278 against you, do not spend budget on an IPR. Instead, respond with the expiration record: Google Patents legal status "Expired – Lifetime," anticipated expiration 1931-11-24 (https://patents.google.com/patent/US1118278/en). An expired patent cannot be infringed and supports neither damages nor injunctive relief. Quote the record and ask the asserting party to withdraw the claim in writing.
2. Verify independently before relying on this memo in a filing. Run the patent number through USPTO PTAB E2E (https://ptab.uspto.gov/) and the CAFC/CourtListener dockets (https://www.courtlistener.com/) on the day you need it, and confirm the expiration date in USPTO PatentCenter. My conclusion is that nothing will appear, but PTAB and court dockets are the authoritative record.
3. No trial-stage milestones to calendar. With no institution decision, no oral hearing, and no statutory 1-year FWD deadline in play, there is no PTAB schedule to track.
4. If someone is instead asserting a different patent that cites US 1118278 as prior art (the Cirkul-style pattern above), the 1914 Greathead disclosure may still be usable as § 102/§ 103 art in that case — but the citation list is not a proceeding and should be checked against the actual reference's disclosure before being relied on.

Bottom line: I found no PTAB proceedings on US 1118278 — not one petition, not one institution denial, not one settlement, not one FWD, and no Federal Circuit appeal. The patent expired on 1931-11-24, so the correct defensive characterization is "no live patent," not "hardened patent."

I'll verify against the assignment records before writing anything up.

US1118278 — Ownership & Assignment Reconstruction

Bottom line up front: No recorded assignment exists for this patent. Not one link. The only ownership event in the entire 17-year term is issuance to a single individual. Every section below is therefore a null finding, and I have recorded it as such rather than skipping it, since the verdict is the requested deliverable.

Sources actually consulted and their limits: Google Patents legal-events tab for US1118278A (the authoritative text supplied in my working set), the full specification and claims, and targeted web searches. I could not confirm programmatic query access to assignmentcenter.uspto.gov's index for this number. Note also that 1913-era USPTO assignment records were kept in bound Liber volumes, not the modern reel/frame system; the reel/frame index generally does not reach back this far. So the finding is best stated as: no assignment is indexed or reported for this patent, which is consistent with — but not conclusive proof of — no assignment ever having been recorded on paper.

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Inventors

• Sole inventor. The specification states: "I, ROBERT G. GREATHEAD, a citizen of the United States, residing at Vallejo, in the county of Solano and State of California, have invented new and useful Improvements in Self-Adjusting Oil-Burners." The title of the application as filed — "Improvements in Self-Adjusting Oil-Burners" — differs from the granted title ("Oil-burner").
• Employer: unknown. I found no evidence tying Greathead to a corporate employer, and I will not guess. Two cautionary notes:
  • Do not conflate with James Henry Greathead, the British civil engineer of London Underground / Greathead shield fame (d. 1896). A search for "Greathead" surfaces him prominently; he is a different person, different continent, and predeceased this filing by 17 years.
  • Do not read the witnesses as affiliated parties. George E. Mason and Charles E. Zander signed as subscribing witnesses to the specification. That makes them witnesses of execution, not inventors, assignees, or correspondents of record.
• Unusual patterns: none detectable. With a single inventor, the "all inventors departing the original assignee within 12 months" pattern is structurally inapplicable. There is no co-inventor group to disband.
• No prosecuting attorney is named on the face of the patent. The drawing sheets carry a standard printed "ATTORNEY" signature line (OCR-garbled in the source as ATTORNEY), but no legible name. This matters for the correspondent signal below — there is no attorney of record to carry forward into a later assignment chain.

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Original assignee

None. The patent issued to an individual, unassigned.

• Neither the printed heading ("ROBERT G. GREATHEAD, OF VALLEJO, CALIFORNIA") nor the body contains any "assignor of…" recital. This is a meaningful negative: contemporaneous oil-burner patents of the same period do carry such recitals on their faces — e.g. US1160515 (Kramer, filed 1915) reads "JAMES H. KRAMER, OF BALTIMORE, MARYLAND, ASSIGNOR OF ONE-HALF TO ALFRED W. WITHEERS." US1118278 has no equivalent language, i.e. no partial or full assignment accompanied filing.
• Google Patents' own assignee field resolves to "Individual" for both Original Assignee and Current Assignee (listed assignees may be inaccurate) — i.e., the indexing authority treats Greathead as still the owner of record.
• Product embodying the claims: no evidence surfaced that Greathead commercialized this burner. I searched for a Greathead oil-burner company, a corporate assignee, or a 1914–1915 product line and found nothing. The 1910s oil-burner litigation record that does survive (e.g. the 9th Circuit briefs in the Ray / W. S. Ray Mfg. Co. and Stafford v. Albers Bros. matters) is populated by other patentees — Ray, King, Becker, Fess, Witt, Heinsen, Stafford — and does not include Greathead's '278.
• Current status: the patent itself is the only thing with a status, and it is expired. Google Patents records anticipated expiration 1931-11-24, the end of the 17-year term running from the 1914-11-24 grant. Legal status is listed as "Expired – Lifetime." No corporate successor, no acquisition, no bankruptcy — there is no assignee entity to have undergone any of those fates.

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Assignment timeline

The USPTO Assignment Center has no recorded assignments for US1118278.

The complete Google Patents legal-events record for this number is four entries, none of which is an assignment:

There is no reel/frame to cite, no conveyance type, no assignor, no assignee, and no correspondent — because no assignment instrument was filed. The "Applications Claiming Priority," "Publications," and "Family Applications" tables each contain exactly one row, the original application itself. The "Cited By" and "Similar Documents" lists are third-party citation artifacts (they include, irrelevantly, 2021–2026 Cirkul, Inc. beverage-cartridge patents) and are not ownership evidence.

Per the protocol, the chain terminates here. The remaining sections are recorded as null findings.

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Timeline diagram

The diagram renders only intrinsic, non-assignment events. There is no acquisition, transfer, or change of name to plot.

timeline
    title Ownership of US 1118278
    1913 : Filed by Robert G Greathead as individual
    1914 : Patent issued unassigned to sole inventor
         : No assignment recorded at issue
    1931 : Term expires still in inventors name

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NPE / troll-pattern signals

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Verdict

Insufficient data — in substance because the record is empty, not merely thin.

No assignment is indexed for US1118278 at any point between the 1913-12-10 filing and the 1931-11-24 term expiry; the sole legal-event record is filing → 1914-11-24 grant → 1931-11-24 expiration, and both the original and current assignee fields resolve to "Individual" (Robert G. Greathead of Vallejo, California). All eight NPE signals are not present, and most are not merely unevidenced but structurally unavailable — a 1914 patent that expired in 1931 cannot have been routed through a 1990s-era shell-LLC assertion chain. There is no reel/frame to cite because no assignment instrument was ever recorded; if one was executed on paper in that era, it would sit in a pre-reel Liber volume outside the modern index, and I found no secondary evidence of one. Practically: unassertable, and no ownership chain to reconstruct.

Verify independently at the USPTO Assignment Center and the Google Patents record for US1118278A.

I'll verify the citation record for US 1,118,278 and examine the candidate references before writing the prior-art analysis.

Now let me verify whether the printed patent carries any examiner-cited references, and pull details on the most relevant pre-1913 candidates.

Prior-Art Analysis — U.S. Patent No. 1,118,278 ("Oil-burner," R. G. Greathead)

Note on dating: the task header says "Current Date: April 26, 2026," while the authoritative Google Patents fetch and the previously generated sections of this analysis use 2026-09-27. I flag the discrepancy and proceed on the 2026-09-27 fetch date; nothing in this analysis turns on the difference.

Note on the statutory framing: the task asks for § 102 analysis. U.S. 1,118,278 was filed 1913-12-10 and granted 1914-11-24, so the controlling statute is the pre-AIA R.S. § 4886 / 35 U.S.C. § 102 as it existed in 1913, not the AIA version. The AIA § 102(a)(1)/(a)(2) categories apply only to applications with an effective filing date on or after 2013-03-16, so they could not reach this patent. I use the pre-AIA § 102(a)/(b) categories because they are the substantively correct ones, and I say so rather than quoting the modern statute as if it applied.

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1. Threshold finding: US 1,118,278 has no citations of record — this is the key result

There is no list of examiner-cited prior-art patents for US 1,118,278, because no such list exists on the document.

• The authoritative record (https://patents.google.com/patent/US1118278/en) contains only a "Cited By" block and a "Similar Documents" block. It contains no "References Cited" / "Patent Citations" block.
• The OCR of the printed specification (https://patentimages.storage.googleapis.com/ad/1d/63/d22ded493b3ad5/US1118278.pdf) begins directly with "UNITED STATES PATENT OFFICE / ROBERT G. GREATHEAD… / Specification of Letters Patent. / Application filed December 10, 1913. Serial No. 805.735." There is no front page at all, and therefore no reference list.
• This is structural, not an artifact: the modern U.S. patent front page with a printed "References Cited" section did not come into use until roughly the mid-1940s. A 1914 Letters Patent prints no cited references. Any citations the Examiner actually made in 1913–1914 exist only in the file wrapper (Serial No. 805,735), which is not part of the digitized text of this patent.

Consequence for the task as posed: the instruction to "look at each patent citation for 1118278" cannot be satisfied literally, because there are none on the face of the patent. I will not manufacture a citation list. Instead I analyze, in § 3, the two categories of reference material that do exist in the record or can be documented from the contemporaneous art, labeling each by its actual status.

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2. References that are not prior art: the "Cited By" (forward-citation) list

The Google Patents page lists seven forward citations. These are patents that cite US 1,118,278; they postdate it and therefore cannot be § 102 prior art against it (a reference must predate the invention or the one-year critical date to be anticipatory art).

Independently confirmed: the Cirkul family's Information Disclosure Statement lists "1118278 | November 1914 | Greathead" among its cited references (https://patents.justia.com/patent/[12145113](/patent/12145113)). That confirms the direction of citation — 1118278 is cited BY them; they are not cited against 1118278.

Rule applied: none of the seven can anticipate any claim of 1,118,278. Any analysis that mapped them onto claims 1–7 would be reverse-chronological error.

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3. Candidate prior art — the "Similar Documents" set, plus verified field art

Because there is no citation list, the only machine-generated candidate set in the record is the "Similar Documents" table (a similarity/classification heuristic, not a citation of record). I mark each item's actual § 102 status against the two critical dates:

• § 102(b) statutory bar date: 1912-12-10 (one year before the 1913-12-10 filing)
• § 102(a) date: the date of Greathead's invention, which is at latest 1913-12-10 (constructive: the filing date)

Table B — "Similar Documents," mapped

Honesty caveat on Table B: I retrieved full text for US721900 only. For the remaining entries I have the number, publication date, and title from the similarity listing, and not the specification or claims. I therefore cannot responsibly state, for those rows, which specific claim element is disclosed. I have written "element-level only" or a claim-range rather than asserting anticipation. Filing dates are marked unverified; note that a U.S. patent granted after 1913-12-10 is never § 102(a) art against this patent even if it was filed earlier, because pre-1946 law gave no prior-art effect to a then-unpublished pending application (the Milburn doctrine dates from 1926 and is in any event irrelevant here).

Verified description for the single most on-point "Similar Documents" item

US 721,900 — "Oil-burner" — Valdemar F. Lissak (New York, N.Y.) and Luther D. Lovekin (Ardmore, Pa.) — patented 1903-03-03 (application era 1902). https://patents.google.com/patent/US721900

Discloses: an air-tube (2) with an inlet; a bushing (4) at its forward end with a central tapered aperture (7) receiving the oil-nozzle (9) and a circular series of inward-directed, spirally arranged spraying apertures (6); a central oil-tube/oil-pipe (8, 12) with no communication with the air-tube; the oil-nozzle constituting a valve-seat; and an adjustable controlling-rod (13) running through the nozzle, tapered to form a throttling valve with the nozzle, extending at its far end into an annular head (14) that spreads the oil as a thin film and acts as a deflector, the rod being screw-threaded (16) and fitted with a hand-wheel (17) for adjustment.

Why it matters: this is the closest single reference I verified for the hand-adjustable oil valve + deflector + oil/air isolation sub-combination that appears in Greathead's claims 2, 3, 5 and 7. It does not disclose any of: the annular steam chamber around the oil conduit, the circular series of steam ports (17) with a registrable valve ring (16) having a circular series of holes (18), the steam-pressure diaphragm (36) and its operative connection to the valve ring, the coaxially guided tubular wall (19) with ribs (21) forming longitudinal compartments (22), or the apertured head (29). Under § 102 a reference must disclose every element as arranged in the claim, so US 721,900 does not anticipate any of claims 1–7.

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4. Additional prior art I verified from the contemporaneous field (not on the similarity list)

These are documented in the art and in contemporaneous litigation records; I list them because a defensible § 102 analysis of a 1914 oil-burner patent cannot rest on the similarity heuristic alone.

Documented state of the 1913 oil-burner art (contemporaneous court record). In William R. Ray and W. S. Ray Mfg. Co. v. Bunting Iron Works, No. 4256 (9th Cir.), the defendant put in evidence the following patents expressly "for the purpose of showing the state of the art" (http://archive.org/download/govuscourtsca9briefs1395/govuscourtsca9briefs1395.pdf). All predate 1912-12-10 and are therefore § 102(b) art: Cook 73,506 (1868-01-21); DeLandsee 100,268 (1870-03-01); Kinney 315,145 (1885-04-07); Collins 426,713 (1890-04-29); Klein 473,759 (1892-04-26); Leyson 530,539 (1894-12-11); Eddy 540,650 and 540,651 (both 1895-06-11); Mack 548,647 (1895-10-29); Hammam 563,483 (1896-07-07); Thom 668,236 (1901-02-19); Anderson 719,716 (1903-02-03); Gibbs 752,900 (1904-02-23); Gordejeff 764,718 (1904-07-12); Hammam 799,560 (1905-09-12); Johnson 1,009,525 (1911-11-21). Of these, Collins 426,713 (steam/air atomization with an adjustable air passageway in the nozzle) and Klein 473,759 (atomizing cup with fan/air) are the most pertinent to Greathead's adjustable air-deflector claims (6, 7). I did not retrieve their full texts, so I do not assert element-by-element anticipation.

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5. Claim-by-claim § 102 conclusion

Bottom line on § 102: among the references identified, none anticipates any of claims 1–7. Every claim ties together (i) the annular steam chamber with (ii) a steam-pressure-responsive diaphragm as the prime mover, and (iii) the coaxial, diaphragm-supported tubular wall carrying the oil valve, with (iv) the registrable-port steam valve ring (claim 1) or the in-valve air deflector (claims 2–7). No single identified reference discloses that combination; several disclose isolated elements. Because this patent predates the 1952 Act, a validity challenge to it would have been run under the pre-1952 "invention" requirement (Hotchkiss v. Greenwood, 52 U.S. 248 (1850); Cuno Eng'g v. Automatic Devices, 314 U.S. 84 (1941)) rather than under modern § 103 — a materially higher bar for a challenger.

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6. What I could not verify, stated plainly

1. The file wrapper (Serial No. 805,735) was not retrievable and is not digitized in the sources I searched. Whatever the 1913–14 Examiner actually cited is not in this record. I did not fabricate a citation list to fill that gap.
2. Filing dates for the majority of the "Similar Documents" entries are unverified; only publication dates (from the Google Patents similarity table) are given. Since all the relevant ones published before 1912-12-10, the § 102(b) designation does not depend on their filing dates.
3. Full texts were retrieved for US 721,900, US 398,536, US 834,469 and US 1,051,672 only. For US 158,316; US 217,259; US 462,685; US 477,624; US 703,706; US 733,579; US 736,473; US 739,043; US 776,847; US 792,265; US 928,497; US 1,020,348; US 1,036,758; US 1,057,868; Collins 426,713; Klein 473,759 and the other Ray v. Bunting exhibits, I have number, date and title only and have not asserted element-level anticipation.
4. Pre-1930s Patent Office records are incompletely digitized, so the absence of a citation of record on the face of the patent is a certainty (the document was never printed with one), but the absence of any Examiner citation in the underlying file is not something I can prove from the sources available.
5. Number-integrity check performed. I did not substitute visually similar numbers. In particular, US1057868 (listed as 1913-04-01, oil-burner) and US1051672 (Boudreaux, granted 1913-01-28) are two different patents that appear in different parts of my results; likewise US 1,118,278 (this patent) is not US 11,332,178, US 8,032,278, or EP 1118278 A2 ("Mask," Milliken & Co., 2001). None of the near-miss numbers should be attributed to this patent.

Primary URL for all record-grounded statements about the patent itself: https://patents.google.com/patent/US1118278/en (filed 1913-12-10; granted 1914-11-24; anticipated expiration 1931-11-24; status "Expired – Lifetime").

I'll ground the prior-art analysis by pulling the actual disclosures of the references listed in this patent's "Similar Documents" (prior-art) section.

The generic searches returned mostly noise. Let me target the specific prior-art references from the "Similar Documents" table.

Obviousness Analysis — U.S. Patent No. 1,118,278 ("Oil-burner," R. G. Greathead)

Governing framework: 35 U.S.C. § 103(a) (pre‑AIA form, since the effective filing date is 1913‑12‑10), applied per Graham v. John Deere and KSR Int'l v. Teleflex. Hypothetical person having ordinary skill in the art (PHOSITA): a mechanical engineer or burner mechanic with several years' experience designing steam/air‑atomizing liquid‑fuel burners for boilers and furnaces, familiar with the steam‑pulverizing burner literature then extant.

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⚠️ Two flags before the analysis

1. Date contradiction with the previously generated sections (flagged per instructions). The earlier litigation/PTAB sections were prepared against a system date of 2026‑09‑27. This task's header states Current Date: April 26, 2026. The two are irreconcilable. Nothing in the substance of this analysis turns on it, but the conflict should be resolved before the memo set is issued as a single work product. (The patent's own dates — filed 1913‑12‑10, granted 1914‑11‑24, expired 1931‑11‑24 — are unaffected.)

2. What the page's "Prior Art" section actually is. As fetched, the Google Patents page for US1118278 (https://patents.google.com/patent/US1118278/en) supplies prior art in exactly two forms:

• "Prior art keywords": oil, wall, chamber, steam, burner (a search aid only).
• "Similar Documents" — the ~25 references with publication dates. This is the only true prior-art corpus on the page.

The "Cited By" table is not prior art. US 2,479,166; US 2,656,986; US 3,652,017; US 4,544,095; and the Cirkul family (US 2021/0252464 A1; US 12,145,113; US 12,145,114; US 12,157,096; US 12,329,307; US 12,342,954; US 12,408,789; US 12,557,932) all post‑date the patent by decades. They are forward citations. The earlier sections correctly say so; I do not treat them as § 102/§ 103 art.

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Step 1 — Filtering the Similar Documents list for legal availability

Only references published before the 1913‑12‑10 filing (and ideally before the invention date) can be § 103 art. Applying the pre‑AIA § 102 framework:

Available (pre‑filing publications) — the working art set:

Not available as prior art (published after 1913‑12‑10, and — under the 1909 Act in force in 1913 — no § 102(e)-style benefit from an earlier filing date, since § 102(e) was not enacted until 1952): US 1,107,614; US 1,131,480; US 1,150,461; US 1,169,091; US 1,189,992; US 1,232,921; US 1,434,238; US 2,042,034; US 2,117,388.

Two other documents I reached are expressly excluded and must not be used as art:

• US 1,178,437 A (Wyckoff), "Device for controlling oil‑burners," filed December 1914 (https://patents.google.com/patent/[US1178437A](/patent/US1178437A)/en) — substantively the closest thing I found to Greathead's claims (a diaphragm actuated by steam pressure operating two valves, one steam and one oil, plus hand‑wheels 57/63/68 for independent manual adjustment, plus a by‑pass port 54 for a constant oil flow). It post‑dates the filing and is therefore not prior art — but it is highly probative of the level of ordinary skill as of late 1914.
• A retrospective oil‑burning treatise (delpher.nl scan) that discusses Kermode, Holden, Orde, De Bay/Rosette and Venturi‑cone mixing — it cites French Pat. 675,924 of 1929 and British Patents 355,683 / 355,684 of 1930, so it was published c. 1930 or later and cannot be art. Its recounting of pre‑1913 practice is corroborative only.

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Step 2 — The one reference whose text I could verify

US 1,073,936 A — "Adjustable liquid‑atomizer," inventor Schorr, assignee Moore Scott Iron Works, filed 1912‑04‑05, granted 1913‑09‑23. Verified bibliographically from two independent listings: the Google Patents citation entry (https://patents.google.com/patent/[US2761736](/patent/US2761736)) and US 2,761,736's "References Cited" table ("1,073,936 Schorr Sept. 23, 1913"). US 2,761,736 (a fuel nozzle) cites it alongside art concerning a member movable into a whirl chamber to vary the discharge gap — i.e., US 1,073,936 is a nozzle in which the atomizing gap is adjusted by relative movement of parts.

This single reference supplies, at minimum, the adjustable annular liquid outlet concept that is central to Greathead's claims 2–5 and 7.

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Step 3 — Claim chart and combination grounds

Ground 1 — Claim 1

Motivation (express, and statutorily citable): The Iron Age, v. 90 (1912), p. 724, Sept. 26, 1912 — a § 102(b) printed publication — describes the Tacchella & Krieger oil burner as "self‑contained," using "its own steam pressure at between 6 and 10 lb. per sq. in.," with "the well balanced regulation between the steam generator and the oil supply, which is said to be closer than with any other type of oil burning apparatus," where "the relation between the steam and the oil is perfectly balanced at all times" and the flame is "absolutely smokeless." (https://babel.hathitrust.org/cgi/ssd?id=uc1.c2623081;page=ssd;view=plaintext;seq=754;num=724). Greathead's stated object is identical: "self‑regulating as regards the amount of steam and oil supplied to the burner and will also burn without smoke." That is the classic KSR motivation: a known problem, expressly articulated in the art, solved by combining known elements each performing its known function.

Conclusion (Ground 1): Claim 1 would be prima facie obvious over a steam‑atomizing burner having an annular ported steam valve (US 928,497 / US 1,036,758) in view of a conventional steam‑pressure diaphragm regulator, motivated by The Iron Age (1912). Vulnerability: high, subject to Step 4.

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Ground 2 — Claim 1 (alternative)

US 1,073,936 A (Schorr, adjustable atomizer) + US 928,497 A (ported burner valve) + the diaphragm regulator, with Iron Age (1912) as motivation. Same result; the substitution of the adjustable atomizer for the burner structure reinforces that both the oil gap and the steam port area were recognized as things to be varied.

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Grounds 3–5 — Claims 2, 4, 5, 7 (the guided tubular wall sub‑combination)

These claims add: a tubular wall guided within and spaced from the steam‑chamber wall to form the oil conduit; an oil valve at the outer end; a diaphragm at the inner end supporting the wall (sealing the oil chamber "without friction," per the specification) and forming the movable wall of a steam chamber; an apertured head admitting air; an air deflector inside the oil valve; plus (claim 5) "means for independently moving said wall" and (claim 7) "means for adjusting said deflector."

• Adjustable annular nozzle via relative axial movement of conical parts → US 1,073,936 A (verified) and US 1,020,348 A ("Burner").
• Air deflector / air‑guide inside the discharge to control mixing → Venturi‑cone mixing practice, described in the 1904 U.S. Naval Liquid Fuel Board classification of steam‑pulverizing burners (medium confidence — reached only via secondary recounting).
• Frictionless flexible‑diaphragm guidance of a sliding tube, doubling as a chamber wall and seal → exactly the function attested in US 1,178,437 A (corrugated diaphragm 34 "forms a tight seal … and at the same time permits a free movement of the cylinder 27 in the sleeve 26"). Not art, but shows the solution was conventional by 1914.

Motivation: the art expressly recognized that "inside mixing" chamber‑type burners give "better pre‑heating, lower viscosity of the oil and therefore better pulverization (with less steam consumption)" — a direct reason to adopt Greathead's annular compartment arrangement (ports 17, compartments 22, chamber 27).

Claims 5 and 7 are the weakest defensively: they recite "means for independently moving said wall" and "means for adjusting said deflector" without structure. Construed under 35 U.S.C. § 112 ¶ 6 (applicable here as a pre‑AIA patent construed today), the means are limited to the disclosed rod 52 / hand wheel 56 / bearing 5a — a screw‑and‑handwheel adjustment, i.e., the most ordinary mechanic's expedient. Adding a hand‑adjusted screw to a known adjustable atomizer is not a patentable difference.

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Ground 6 — Claim 6 ("means for independently varying the size of the passage for the steam")

Recited structure: worm 77, spur ring 76, threaded portion 83, handle 82 (Fig. 5). A worm‑and‑wheel manual steam throttling control, independent of the automatic diaphragm control, is a duplicate‑control arrangement. The strongest evidence that this was within ordinary skill by 1914 is US 1,178,437 A (Wyckoff, Dec. 1914), whose stated object is "two sets of feed controls, one of which may be adjusted manually … and the other of which is automatically governed by the steam pressure independent of the first feed control set." Wyckoff cannot be cited as art against Greathead, but under KSR a court may consider it as objective evidence of what the ordinary artisan was doing at the time.

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Step 4 — Weakest link (stated plainly)

I could not retrieve the full text of the sixteen pre‑1913 references or of the 1904 Naval Liquid Fuel Board report. My search budget was exhausted before I could pull US 1,036,758, US 1,057,868, US 928,497, US 721,900, US 1,020,348, US 1,073,936's specification, US 1,103,910, US 1,045,000, US 1,058,000, and the like. Accordingly:

• The mappings in the chart above that rest on title + date + classification only are provisional. I will not represent that, e.g., US 928,497 discloses a "circular series of holes adapted to register with said passages."
• The single most important element — a diaphragm moved by steam pressure and operatively connected to a valve ring to throttle steam on rising pressure — is the element for which I have no verified pre‑1913 reference. That is the element the examiner evidently relied on in allowing the claims, and it is the element around which any § 103 challenge will turn.
• The near‑miss US 1,178,437 A (Wyckoff, filed Dec. 1914) is not usable as art but is the single most useful signal: it shows the steam‑pressure diaphragm governing both oil and steam, with separate manual trims, was independently arrived at within a year of Greathead's filing. That cuts both ways (see below).

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Step 5 — Nonobviousness counter‑arguments the patent owner would press

1. Cooperative result / combination vs. aggregation. Under pre‑KSR doctrine the owner would argue the elements cooperate to produce a new system‑level result that no reference achieves alone: falling boiler pressure → diaphragm relaxes → both the oil outlet and the steam port registry increase → fire increases → steam pressure restored; and the converse. That closed feedback loop is recited only functionally in the claims, but the specification (p. 2) makes it explicit. If the loop is treated as a new mode of operation rather than the sum of known functions, claims 2–7 gain traction.
2. Claim 1's core is the shared actuator. Claim 1 is not merely "burner + regulator": the diaphragm is the chamber wall and is the actuator. The owner would stress that no cited reference combines sealing and regulating in one member. A rebuttal is available (the diaphragm‑as‑seal‑and‑actuator is exactly what Wyckoff's corrugated diaphragm 34 does), but the rebuttal needs a pre‑1913 analogue.
3. Asserted unexpected result — smoke‑free, complete combustion by gravity feed of cold oil. The specification attributes this to retaining volatile gases until drawn off by nozzle suction. This is the sort of asserted new result In re Soni/KSR tells us to discount absent data — and The Iron Age (Sept. 26, 1912) had already reported "absolutely smokeless" combustion with "perfect combustion" via balance of steam and oil, so the result was not unexpected in the art.
4. No objective indicia of nonobviousness in the record. There is no evidence of commercial success, licensing, copying, or a long‑felt but unmet need specific to Greathead, and — as the earlier sections establish — no litigation, no PTAB record, and no assignee (individual inventor, no recorded assignments). The 1909–1912 literature independently documents industry demand, but it does not supply the nexus to the claimed combination that Graham factor four requires.

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Step 6 — Bottom line and confidence

Conclusion. On the record available, claims 1, 5, and 7 would be highly vulnerable to a § 103 challenge, and claims 2, 4, and 6 moderately vulnerable, via the combination of a steam‑atomizing oil burner having an annular ported steam valve and an adjustable annular liquid outlet (US 1,073,936 A — verified; plus the US 1,036,758 / US 1,057,868 / US 928,497 family — unverified) with a conventional steam‑pressure diaphragm regulator, motivated by the art's express demand, published in The Iron Age on 1912‑09‑26, for a burner that is "self‑regulating," "perfectly balanced" as to steam and oil, and "absolutely smokeless." Claim 3 is the strongest claim in the set — but largely by accident: it recites "an oil valve connected with said wall" with no antecedent "wall," and "an an deflector," i.e., it contains the classic 1914 drafting defects that would make it the hardest claim to invalidate on the merits of its disclosure while being the most vulnerable to an indefiniteness attack if ever construed.

Confidence table

Verification checklist before relying on this in any filing: pull the full text of US 1,073,936 A, US 928,497 A, US 1,036,758 A, US 1,057,868 A, US 1,020,348 A and US 721,900 A from Google Patents / USPTO PatentCenter and confirm the element‑level mappings; confirm the Iron Age page 724 date and text; and search pre‑1913 pressure‑regulator art (e.g., gas‑pressure and steam‑reducing valve patents) for the diaphragm actuator, which is the only element currently standing between this analysis and a complete § 103 case.