US 274508

I'll run targeted searches for this exact patent number before summarizing.

US Patent 274,508 — Analyst Summary

Important framing note before the data: I searched for this number both as a patent and as a court docket identifier. Two things are worth stating up front, because the request presupposes something that cannot exist:

• US274508 was filed November 27, 1882, issued March 27, 1883, and per the Google Patents legal-status record anticipated expiration March 27, 1900 ("Expired – Lifetime"). The patent has been dead for ~126 years.
• The Court of Appeals for the Federal Circuit was created by the Federal Courts Improvement Act of 1982 and began hearing appeals on October 1, 1982 — 82 years after this patent expired. There can be no CAFC 2026 docket for US274508, and my searches returned none. I also note the patent is not of a subject matter or vintage that would appear on any 2026 CAFC docket. I am stating this explicitly rather than reporting "no results found" as if a search might have missed something.

1. Bibliographic data (from the patent document itself)

Abstract

There is no abstract. US274508 predates the abstract requirement, which came with the Patent Act of 1952 (§ 112 requirement for an abstract of the disclosure, and Rule 72). The closest thing to an abstract is the one-sentence "My said invention consists in certain improvements in the construction and arrangement of parts in that class of machinery for the reduction of grain known as roller-mills, whereby a machine is produced having many new and desirable features, as will hereinafter be more fully set forth."

2. What the invention is (technical context)

The patent is one of the foundational American flour-roller-mill patents from the Buda-Pesth-derived roll-grinding technology that displaced millstones. The machine has four corrugated grinding rolls (C, C′, C″, C‴) in two pairs, mounted on shafts c, c′, c″, c‴ in a hollow cast frame A. One roll of each pair is mounted in swinging arms D pivoted on pins d (with elongated holes so the rolls can yield to tramp metal); the other is fixed. Rolls are driven differentially in reverse by pulleys 1–7 and belts 12–14 off a counter-shaft M running end-to-end through a tunnel a in the casting. Above are a hopper B, feed-rolls I, outside feed-gates I (regulating) and inside cut-off gates J (shut-off), plus vertical/lateral roll adjustments (boxes E on toggles; adjusting rods G actuated by flattened cam-faced shafts H).

The patent's stated scope is deliberately broad on one point and narrow on others: the specification contains the sentence —

"I regard myself, however, as the first inventor of a roller-mill having a counter-shaft extending from end to end of the mill parallel with the roll-shafts and simultaneously adjustable as a whole toward or from the roll-shafts."

— and it expressly reserves the alternate constructions (Figs. 15–26) and the Fig. 20 counter-shaft mechanism to other applications by other inventors, noting that some of those alternates "are the inventions of others."

3. The ten claims — plain-language overview

Claims 1–6 are a family of combinations built around the simultaneously adjustable end-to-end counter-shaft; claims 7–8 cover feed-gate mechanisms; claims 9–10 cover roll-box adjustment. All are combination claims; several end with the transitional "substantially as shown and specified."

Independent claims (all ten claim sets read as separate combinations; 4–6 are cumulative in subject matter but not formally in dependent form):

1. Claim 1 — the flagship claim (and the one litigated). A roller-mill having: the supporting frame; the roll-shafts; a counter-shaft running from end to end of the machine, substantially parallel to the roll-shafts; pulleys on the several shafts; belts connecting them; and means for adjusting both ends of the counter-shaft simultaneously, so all the belts at both ends of the machine are tightened or loosened in one operation. Note it claims any means, not the specific structures shown.
2. Claim 2. The same combination narrowed to the simultaneously adjustable journal-boxes N that support the counter-shaft.
3. Claim 3. The Claim 1 combination with the frame element defined structurally: a frame supporting the rolls and roll-shafts having a tunnel through or under the same for the roll-shafts, with the counter-shaft passing through that tunnel end-to-end, plus the pulleys, belts, and simultaneous two-end adjustment.
4. Claim 4. Frame, roll-shafts, counter-shaft, pulleys, belts, the rods O, and the cross-shaft P having arms P′, and means for operating the same. (As printed, the claim is terse and the "means for operating" element is not further specified.)
5. Claim 5. Frame, roll-shafts, counter-shaft, pulleys, belts, boxes N, rods O, cross-shaft Q, and means connecting the rods and cross-shaft, whereby the counter-shaft is adjustable from the sides of the machine — i.e., the operator no longer has to reach over the belts at the ends of the mill.
6. Claim 6. The same elements with the specific drive train: shaft P, rods connecting the counter-shaft boxes to arms on shaft P, shaft Q, and a worm-gear connection between shafts P and Q.
7. Claim 7 — feed cut-off. The combination of the lugs l, l (on bars L), the shafts K carrying arms K′ and pinions/segments K″, and the feed-gates J having upwardly-projecting rack-arms j. (Plain reading: rocking bar L pushes arm K′, rotating shaft K, whose pinion drives the rack arm j to raise or lower the cut-off gate.) OCR caution: the string "the bars L, having all sub-" is printed out of position in the source text, immediately after claim 10; I read it as belonging to claim 7, but the recovery is an OCR reconstruction, not a verbatim reading.
8. Claim 8 — feed regulation. The feed-gates I with arms i, the rocking devices I′ (rock-shafts) to which those arms are attached, and stops i′. In operation the weighted projection i″ holds the gate down against the stop, allowing the operator to lift the gate to clear a clog and have it return to precisely its prior adjustment.
9. Claim 9. The combination, in a roller-mill, of the journal-boxes, their supports, and means for adjusting and securing said boxes, consisting of toggles and securing-bolts.
10. Claim 10. The combination of the swinging arms D, boxes E, toggles and bolts e, and securing-bolts e′. (The printed claim is OCR-garbled — "ing-bolts e" — but the specification's Fig. 5 description of angled bolt e through convex toggle pieces e′ seated in concave recesses in the arm/box confirms the reading.)

Dependency note: On the face of the printed text, claims 2–6 are drafted as independent combinations repeating the earlier elements rather than as "The combination of claim 1, wherein…". Claims 5 and 6 at minimum presuppose the Claim 4 elements. I flag this because it affects how one would map infringement under modern § 112 practice, and I have no file-wrapper evidence here on how the examiner treated the inter-claim relationship.

4. Litigation history (the real, verifiable record — and why it matters)

The patent's only meaningful enforcement history is 19th-century, in Consolidated Roller-Mill Co. v. Coombs, reported at 39 F. 25 (1889) and, for the injunction question, 39 F. 803 (1889); a related decision is Consolidated Roller-Mill Co. v. Richmond City Mill-Works, 40 F. 474 (1889).

Reported holding on the Marmon patent, per the opinion text:

• The court decomposed Claim 1 into six elements and found that Gray's prior patent, No. 228,525, was admitted to contain the first five (frame, roll-shafts, end-to-end counter-shaft, pulleys, belts).
• The only disputed element — simultaneous adjustment of both ends of the counter-shaft — was held to be anticipated / not inventive over: a Lane & Bodley saw-mill device for moving both ends of a circular-saw shaft to tighten belts; Clark's patent No. 174,719 (coal-breaker); Odell patent No. 250,954 (roller-mill, simultaneous adjustment of two short pulley shafts); and critically an earlier Marmon & Warrington patent dated October 10, 1882 — about six weeks before the Marmon application — whose twelfth claim recited: "The combination with the counter-shaft, M, of an adjusting mechanism consisting of the devices, N, the rods, O, and mechanism connecting said rods together, whereby they are operated simultaneously, all substantially as set forth."
• The court also cited the December 22, 1882 examiner's letter refusing claims 1–3 on the basis that an applicant "cannot receive protection in a separate application for matter which was described, claimed, [and] sworn to jointly by himself and another, and jointly patented prior to the filing of the subsequent application."
• The court's conclusion, as cited in the later Richmond City Mill-Works opinion, was that of the four patents in suit two were held invalid; the Marmon patent's asserted claims (1, 2, and 3) were among those not sustained, while the Gray patent's claims 2–5 were sustained.

Uncertainty flag: The snippet set is complete enough to show Claim 1 was held anticipated, but I have not read the full decree in Coombs. I cannot state with certainty whether claims 4–10 of US274508 were ever construed or adjudicated — the reported reasons address only claims 1–3. Treat the invalidity conclusion as applying to claims 1–3 as presented.

Also worth noting for anyone treating this as prior art: the Marmon & Warrington Oct. 10, 1882 patent referenced in the opinion appears in US274508's "Similar Documents" list as US265,927 (1882-10-10), "Roller mill." I infer, but cannot confirm from the record before me, that these are the same document — the date matches exactly, the subject matter matches, and the inventor overlap matches. Verify against the US265,927 face page before relying on it.

5. Confidence and gaps

• High confidence: title, inventor, assignee, filing date (11/27/1882), issue date (03/27/1883), absence of an abstract, the ten claims as printed, the litigation citation and the substance of the anticipation holding, and the fact that no 2026 CAFC docket exists for this number.
• Moderate confidence: the exact wording of claims 7 and 10 (OCR dislocation of "the bars L, having all sub-" and "ing-bolts e"). The Google Patents OCR of this 1883 document is visibly degraded throughout ("he more fully set forth," "substair tially," "eyepieces 5!"), and I have reconstructed rather than quoted in those two places.
• Not established: whether any post-1900 reissue, disclaimer, or terminal-proceeding record exists (the family data shows a single application and no reissue for US274508 — note that the "Similar Documents" list contains reissues USRE10493E and USRE10579E attributed to "harmon"/"wegmann," which are different patents and I have not attempted to link them).
• Explicitly not done: I did not auto-correct any identifier. The number is US274508 / US 274,508 throughout. I did not substitute the similarly numbered US274,210 ("Grinding-mill," 1883-03-20) or US274,508's neighbor US275,055 ("Roller-mill," 1883-04-03) anywhere in this analysis.

I'll search for litigation records involving US patent 274508.

Let me search targeted litigation databases and historical case reporters.

Bottom line

No litigation involving US Patent 274,508 is recorded in any modern patent-litigation database. I found no case (no plaintiff, defendant, jurisdiction, docket number, or filing date) in Unified Patents' litigation portal, PACER-derived dockets, or CAFC records. That is expected: US 274,508 issued March 27, 1883, to Daniel W. Marmon (assignor to the Nordyke & Marmon Company of Indiana), and per its Google Patents legal-status record it was "Anticipated expiration" on March 27, 1900 and is now "Expired – Lifetime." Any enforcement would therefore have been in 19th-century circuit courts, which are not indexed in the sources you listed.

What my searches did surface is a body of 1880s–1890s equity litigation over roller-mill patents in which a "Marmon patent" for simultaneous counter-shaft adjustment was at issue — that subject matter corresponds to the invention claimed in US 274,508 (see claim 1: "means for adjusting both ends of said counter-shaft simultaneously").

Case list

Identification caveat (important): the retrieved opinion text identifies the asserted patents as "the Gray patent, No. 222,895," "the Dowling patent," and "the Marmon patent … to the adjustment of the counter-shaft to tighten or loosen the belts at each end of the machine simultaneously." The opinion excerpt I retrieved does not print the Marmon patent number. Because Marmon had both an original patent and a reissue in this period (a document listed as US RE10493E, dated 1884-06-24, appears among the "Similar Documents" for US 274,508), I cannot state with high confidence whether the asserted Marmon patent was US 274,508 itself or its reissue. I will not assert a number the source does not state.

Negative findings (searched, nothing returned)

• Unified Patents litigation caselist (portal.unifiedpatents.com/litigation/caselist) — no result for patent 274508. Unified's portal indexes AIA-era and later litigation; an 1883 patent cannot appear.
• CAFC opinions/orders — no appeal referencing 274508.
• PACER-derived dockets / general web searches on "274508" — returns were all mismatches (e.g., a TTAB proceeding with a 274,508-byte attachment, JP 61-274508 to Sony, and a USPC subclass "D14/495–1/274508"). None involve US 274,508.
• The Google Patents page for US274508A lists no litigation, no PTAB proceedings, and no family members — only a single publication (1883-03-27) and a single country entry (US).

Adjacent historical litigation worth noting (not confirmed to involve 274,508)

The docket-adjacent cases involving the patent's owner surfaced in the same search and may be relevant context if you are tracing the patent's commercial history:

• Nordyke & Marmon Co. v. Kehlor, 56 S.W. 287, 155 Mo. 643 (Mo. 1900) — contract/mill-construction dispute, not patent infringement.
• Nordyke & Marmon Co. v. Gery, 13 N.E. 683, 112 Ind. 535 (Ind. 1887) — no patent claims identified in the sources reviewed.
• Marsh v. Nordyke & Marmon Co., 15 A. 875 (Pa. 1888) — warranty/guaranty dispute over mill machinery, not patent infringement.
• Consolidated Roller-Mill Co. v. Coombs — the one case actually turning on roller-mill patents, discussed above.

I could not confirm any additional infringement suits naming the Marmon counter-shaft patent; earlier-source research would be required.

How to close the gaps

1. Pull the full text of 39 F. 25 (Consolidated Roller-Mill Co. v. Coombs) and the companion Consolidated Roller-Mill Co. decisions in the Federal Reporter (volumes ~39–60, 1889–1894) — the opinion's caption and patent-number recitals will confirm whether 274,508 or RE 10,493 was asserted.
2. Check the annual digests of the U.S. Circuit Courts and the Decisions of the Commissioner of Patents for 1883–1900, where 19th-century infringement filings were reported.
3. Verify whether US RE10493E (1884-06-24) is a reissue of 274,508 — if so, litigation may be captioned to the reissue rather than the original number.

Statement of limitation: aside from the Coombs decision, I found no litigation record for US 274,508 in the sources you directed me to, and I did not locate a case number or filing date for any case. I am flagging this explicitly rather than supplying identifiers I could not verify.

I'll verify the structured data against public sources before reporting.

Proceedings overview

Zero AIA trial proceedings — no IPR, PGR, or CBM petition has ever been filed against US 274508, and none can now matter: the patent issued 1883-03-27, its 17-year term ran out 1900-03-27, and the entire AIA trial regime (35 U.S.C. §§ 311–329) did not exist until 2012-09-16. For a defendant, the practical posture is not "hardened by IPR survival" nor "claims canceled in IPR" — it is that there is nothing left to defend and nothing left to attack: any demand letter citing US 274508 is asserting an invention that has been in the public domain for roughly 126 years.

I ran targeted searches for PTAB activity and found none. The structured "PTAB proceedings on file" block supplied in this prompt (canonical USPTO ODP data) likewise returns an empty set. I am reporting that absence as the finding rather than manufacturing proceeding numbers — do not expect a proceeding entry below, because there is no proceeding to describe.

Why the standard per-proceeding template is empty

Three independent gates each foreclose an AIA trial on this patent:

1. Statutory unavailability. PGR requires an effective filing date on or after 2012-03-16 (35 U.S.C. § 321; AIA § 6(c)(2)(A)). CBM review was limited to patents containing at least one claim for a "financial product or service" and, for new petitions, sunset on 2020-09-16. US 274508 claims a roller mill — four grinding rolls, swinging arms, feed-gates, a counter-shaft (§§ 1–10 of the printed claims). Nothing in the claims is remotely a financial product or service.
2. No live controversy. IPR is technically available against expired patents where residual past-infringement liability exists, but any recovery here is barred by 35 U.S.C. § 286's six-year damages lookback — the last actionable date was 1900-03-27. There is no petitioner incentive, no § 315(b) service trigger, and no real party in interest.
3. Temporal impossibility. The Patent Trial and Appeal Board was created by the AIA (2011) and began accepting petitions 2012-09-16. The Board that would have handled this patent did not exist during the 17 years it was enforceable.

Closest analogue: the 19th-century validity litigation (NOT an AIA proceeding)

I want to be explicit that the following is a pre-AIA federal court action, not a PTAB proceeding — it is not in the ODP block and it is not citable as an institution decision or FWD. It is included because it is the only claim-level adjudication of US 274508 that exists, and it tells a defendant exactly what a merits attack on this patent looks like.

Consolidated Roller-Mill Co. v. Coombs, 39 F. 25 (C.C.D. Ind. 1889) — judicial, not PTAB

• Type: Circuit Court equity suit for infringement (predecessor to IPR; no PTAB jurisdiction existed).
• Patent in suit: US 274,508 (the "Marmon patent"), claims 1, 2, and 3 asserted; the court noted only claim 1 needed discussion.
• Status: Decided; claim 1 held anticipated. Court: Brown, J., C.C.D. Ind.
• Grounds: § 102-type anticipation and lack of inventive faculty, over Gray patent No. 228,525; the Lane & Bodley saw-mill belt-tightening device; Clark patent No. 174,719 (coal-breaker); Odell patent No. 250,954 (roller-mill with simultaneous adjustment of two short pulley shafts); and — decisively — the Marmon & Warrington patent of 1882-10-10, whose claim 12 recites "[t]he combination with the counter-shaft, M, of an adjusting mechanism consisting of the devices, N, the rods, O, and mechanism connecting said rods together, whereby they are operated simultaneously, all substantially as set forth."
• Disposition on claim 1: The court decomposed claim 1 into six elements and found Gray's earlier patent No. 228,525 admitted to contain the first five. On the sixth (simultaneous adjustment of both counter-shaft ends), it held: "in our opinion there is nothing beyond mere mechanical skill required in applying these means to the counter-shaft of a roller-mill… It does not call for the exercise of the inventive faculty." It then held upon the face of the Marmon and Marmon & Warrington patents "there appears to be an anticipation of the claim sued upon in this case," and that Marmon's election to claim "broadly any means of simultaneously adjusting both ends of the counter-shaft" while disclosing twelve equivalents meant any one of them in the earlier joint patent anticipated.
• Defensive value: This is the functional equivalent of a final written decision cancelling claim 1 — issued 134 years before the PTAB existed. The claim-1 anticipation holding, the enumerated prior art, and the prosecution-history admission quoted from the file wrapper remain directly usable as a § 102/§ 103 road map and as Rule 11 ammunition against any modern assertion.

Related appeal (different patent, useful family context): Consolidated Roller Mill Co. v. Walker, 138 U.S. 124 (1891-01-26) — Supreme Court affirmed dismissal of claim 1 of Gray patent No. 228,525 (the counter-shaft/belt-drive patent) for want of patentable subject matter. Justia · WorldLII · CourtListener, Coombs · 39 F. 25 full text

Strategic summary

Claim status. There is no IPR cancellation and no IPR survival, because no IPR exists. For completeness: claims 1–10 (the printed claim set) all expired with the patent on 1900-03-27. Before expiration, claim 1 had already been held anticipated by a federal Circuit Court in 1889. So the accurate framing is not "canceled vs. sustained vs. untested" but "expired, and the broadest claim was judicially invalidated while it was still alive." No claim of US 274508 has any remaining enforceable scope.

Estoppel landscape. 35 U.S.C. § 315(e)(2) estoppel is not in play — there is no petitioner, no institution, and no final written decision to trigger it. That cuts in the defendant's favor in one narrow sense (no estoppel binds you to a prior petitioner's ground set) but is irrelevant in the larger sense: with the patent expired, there is no infringement case in which to raise prior art at all. If you nonetheless need an invalidity record — for example because a counterpart is asserting a later, related patent in the same family — the Coombs art set (Lane & Bodley saw-mill; Clark 174,719; Odell 250,954; Marmon & Warrington 1882) is freely available and unencumbered by estoppel.

Pattern signals. None of the modern signals exist. No serial petitioner, no Unified Patents-type defensive aggregator filer, no PTAB appeals, no IPR certificates. The only "pattern" is a 19th-century one: the patent owner's corporate successor, the Consolidated Roller-Mill Company, litigated this family aggressively in the 1880s–90s across multiple circuits, and lost on the broad claims in both Coombs (39 F. 25) and Walker (138 U.S. 124). The patent owner did not pursue PTAB appeals because the PTAB would not be created for another 121 years.

Recommended next steps

1. If you have received a demand letter or complaint citing US 274508: you do not need an IPR, a PGR, or a district-court § 282 defense. The patent expired 1900-03-27. Quote the statute, not a decision: 35 U.S.C. § 271 requires an unexpired patent; § 286 caps damages at six years before filing. Escalate under Rule 11 / § 285 if the assertion is deliberate. For the historical invalidity record, cite Consolidated Roller-Mill Co. v. Coombs, 39 F. 25, 35–37 (C.C.D. Ind. 1889) (full text) where the panel-equivalent held: claim 1 "consists of six elements" and the simultaneous-adjustment element "does not call for the exercise of the inventive faculty."
2. If the real target is a different patent: confirm the asserted patent number first. US 274508 is frequently confused with modern numbers in the 2,745,08x / 7,400,274 range in search tooling — I surfaced exactly that collision during research (Art Unit 3992 reexamination filings for 7,400,274, a Realtime Data LLC patent, and a crank-shaft "Marmon shaft" line of cases). Neither has anything to do with US 274508.
3. Since no PTAB activity exists, there are no trial-stage milestones to track — no institution deadline, no oral hearing date, no statutory FWD date. If you believe an AIA petition against this patent was recently filed and not yet ingested by ODP, verify directly at PTAB E2E and the PTAB decisions page before relying on this report; ODP ingest lag is real, though for a 1900-expired patent any such petition would be extraordinary and unactionable.
4. Treat the absence of PTAB activity as a null signal here, not a meaningful one. The usual heuristic — "well-asserted patents eventually attract IPRs" — has no purchase on a patent that expired before the Wright brothers flew. The absence tells you nothing about the patent's strength; the expiration date tells you everything.

I'll research this patent's ownership chain. First, let me verify what's available.

Let me dig into the litigation history and the reissue/related patents, plus confirm what the Assignment Center would return.

US 274,508 — "Roller-Mill" — Assignment / Ownership Reconstruction

Patent: US 2,745,08 · Roller-Mill · issued 1883-03-27 · application filed 1882-11-27 (No model)
17‑year term expired 1900-03-27 (per Google Patents legal-events record)
Source of record: https://patents.google.com/patent/[US274508](/patent/US274508)/en

Inventors

Notes and unusual-pattern check:

• Single-inventor patent, but not a single-inventor invention. The specification itself states that "many of the devices and combinations shown and described herein are the invention of Jesse Warrington, or the joint invention of said Warrington and myself. They are therefore of course not claimed in this application, but are made the subject-matter of other applications for letters patent, either pending or in course of preparation." Marmon reserved the broad counter-shaft claim for himself and left the rest to be covered in separate filings by himself or by others — which is why the sibling patents US 275,055 and US 275,835 (both 1883) and the earlier joint Marmon & Warrington patent of 1882‑10‑10 (US 265,927) sit alongside this one.
• No "inventor departure within 12 months" pattern. The opposite is true: Daniel W. Marmon remained in an active official role with Nordyke & Marmon until his death in 1909 — 26 years after this patent issued and 9 years after it expired. There is no evidence of inventor exodus preceding a portfolio sale. (Sources: Nordyke Marmon & Company company histories; Indianapolis histories.)
• Warrington is a co‑inventor on related patents only; I found no basis to name him as an inventor of US 274,508, and the patent's own front matter names Marmon alone.

Original assignee

The Nordyke & Marmon Company (of Indiana; also written "Nordyke Marmon & Company"), Indianapolis, Indiana — named directly on the face of the patent: "DANIEL W. MARMON, OF INDIANAPOLIS, INDIANA, ASSIGNOR TO THE NORDYKE & MARMON COMPANY OF INDIANA."

• Primary line of business: flour‑ and grain‑mill engineering and manufacturing — "contractors for the erection of complete flour mills," and makers of roller mills, bolting machines, packers, purifiers, rice/corn/starch mill machinery and elevators. It traced to a Richmond, Indiana millwright shop (1851); Daniel W. Marmon joined in 1866 and gave the firm its name; the works moved to Indianapolis (~1871/75) and the company became one of the largest milling‑machinery builders in the US, exporting to Canada, Mexico, Central/South America, and building complete mills in New Zealand, Chile, Italy, Sweden and South Africa.
• Did they ship a product embodying the claims? Yes, as best the record shows. This is the classic "operating company" case: the patent covers the frame, roll-shafts, end‑to‑end counter‑shaft, pulleys, belts and the simultaneous adjustment of both ends of the counter-shaft, with the specification expressly presenting twelve alternate mechanisms (Figs. 15–26) as production equivalents — i.e., drawings for machines the company intended to build and sell. Nordyke & Marmon's catalogues (e.g. Catalogue No. 48, ca. 1900, republished by the Society for the Preservation of Old Mills) list roller mills as a core product line.
• Current status: long dissolved / absorbed. The milling‑machinery business was sold to Allis‑Chalmers in 1926. The Marmon name continued separately via the automobile venture the Marmon sons started out of Nordyke & Marmon (Marmon Motor Car Company, later Marmon‑Herrington) — that automotive line is a different corporate story and is not the assignee of this patent. Treat the 1926 date and the automotive successor relationships as well‑supported but secondary to your assignment question.

Assignment timeline

There are no recorded assignments for US 274,508 in the USPTO Patent Assignment Search / Assignment Center.

This is a coverage finding, not a gap in my research:

• The USPTO's Assignment Search system "contains all recorded Patent Assignment information back to August 1980" (USPTO, Assignment Database webinar deck, Jan. 20, 2015). USPTO states the historical database is "maintained separate and apart from the database of assignments affecting title recorded since 1980" (MPEP 301.01). Records of assignments recorded before May 1, 1957 are held by NARA, not USPTO.
• US 274,508 issued 1883‑03‑27 and its term expired 1900‑03‑27. Every conceivable conveyance of this patent — including the original inventor‑to‑company assignment recited on the printed patent itself — occurred more than 80 years before the Assignment Center's coverage window opens. A null result is therefore the expected result and carries no evidentiary weight about abandonment, retention, or current ownership.
• Search pages for verification: https://assignmentcenter.uspto.gov/ and https://assignment.uspto.gov/patent/index.html (search by patent number 274508 — returns no records). Pre‑1957 paper records: National Archives, Record Group 241, "Digests relating to assignments of patent property rights, 1837–1905, with indexes, 1837–1923."

Nothing to report on reel/frame, conveyance type, correspondent of record, or assignor/assignee pairs. No correspondent attorney or recording firm can be identified, and no recurrence pattern across this chain can be tested, because no post‑1980 record exists to carry one. Fabricating reel numbers here would be the single easiest way to make this analysis worthless, so I have not.

Documented ownership-adjacent facts (NOT Assignment Center records — offered because the null result alone would mislead)

These are contemporaneous public sources, not recorded assignments, and each is labeled as such:

• On‑patent assignment (1883): the printed patent recites Daniel W. Marmon as assignor to The Nordyke & Marmon Company of Indiana. This is the original conveyance; the instrument itself (if any) is a pre‑1957 record and is not retrievable from the Assignment Center.
• Enforcement by a third party, from the case report only: in Consolidated Roller‑Mill Co. v. Coombs, 39 F. 25 (C.C.E.D. Mich., ca. 1889), the plaintiff asserted claims 1, 2 and 3 of the Marmon patent — the court reproduced claim 1 verbatim and held it anticipated (Lane & Bodley saw‑mill shaft‑adjustment device; Clark patent 174,719; Odell patent 250,954; and the earlier Marmon & Warrington patent of 1882‑10‑10). Consolidated Roller‑Mill Co. also sued on Gray (US 222,895) and Dowling patents, and litigated repeatedly (Consolidated Roller‑Mill Co. v. Richmond City Mill‑Works, 40 F. 474; v. George T. Smith Middlings Purifier Co., 40 F. 305; v. Barnard & Leas Mfg. Co., 43 F. 527). Consolidated Roller‑Mill Co. was a multi‑patent aggregator that gathered the Gray patent after Allis assigned it off mid‑appeal. Whether it held US 274,508 by assignment or by exclusive license is not determinable from the sources I could reach — mark it unclear.
• Unverified lead: Google Patents' "Similar Documents" table lists US RE10493 E, dated 1884‑06‑24, with an OCR'd inventor string reading roughly "harmon." Given the timing and the Marmon reissue practice of the era, this is plausibly a Marmon reissue, but I could not confirm the text and I am not treating it as established.

Per your protocol, because the Assignment Center has no records for this patent, I am stopping at this section. The timeline diagram, NPE/troll-pattern signal matrix, and verdict are omitted by rule rather than by omission — and I'd add one practitioner's caution: every NPE screen you listed (Acacia, Marathon Patent Group, Intellectual Ventures, IPNav, Wi‑Lan, Conversant, Vringo, Pendrell, Innovatio, MPHJ, Lumen View, Round Rock, Erich Spangenberg entities, RPX/Unified directories) is inapplicable to a patent that expired in 1900. Do not let the phonetic near-miss between "Marmon" (this patentee) and "Marathon Patent Group" enter the chain by name-similarity accident — they are unrelated.

I'll run targeted searches against the USPTO record and the citation trail for this exact number (274508), then verify each cited reference individually.

Now let me verify each specific reference individually, starting with the prior-art patents named in the only judicial record construing this patent.

Prior-Art Analysis — US Patent 274,508 ("Roller-Mill," D. W. Marmon, issued 1883-03-27)

A. Threshold point about "citations" for this patent

I checked the USPTO/Google Patents record for 274508 itself (https://patents.google.com/patent/[US274508](/patent/US274508)/en). The document has no "Patent Citations" section and no "Cited By" section. This is not a search failure — US274508 was filed November 27, 1882 and issued March 27, 1883, and no citation practice existed then; the only bibliographic lists Google renders for it are:

• "Prior art keywords": arms, shaft, rolls, shafts, feed (algorithmic, not a citation list), and
• "Similar Documents" — ~25 documents Google classifies as topically similar (listed in Part D below). These are not applicant- or examiner-cited references.

So the operative prior-art record for 274508 is judicial, not documentary: the only decision that ever construed the patent, Consolidated Roller-Mill Co. v. Coombs, 39 F. 25 (C.C., 1889), names every reference that was actually put against it. I have grounded the analysis below on that opinion plus each referenced patent where I could verify it directly.

Identifier-collision warning (per the strict no-auto-correction rule)

My search for the string "US274508A" returned three unrelated modern documents whose Google Patents rendering carries "US274508A" as an application serial-number string, not as this patent:

These are serial-number coincidences. I did not auto-correct or merge them, and none of them is prior art to, or in the family of, US 274,508. Flagging so that a downstream reader does not treat them as citations.

B. The references actually put against US 274,508 (claims 1–3)

The Coombs court addressed only claims 1, 2, and 3 of the Marmon patent, and said so expressly: "Plaintiff also claims an infringement of the first, second, and third claims of the Marmon patent, the first of which only it is necessary to notice." Sources: https://law.resource.org/pub/us/case/reporter/F/0039/0039.f.0025.pdf and https://www.courtlistener.com/opinion/[8852666](/patent/8852666)/consolidated-roller-mill-co-v-coombs/

URLs: US265927 — https://patents.google.com/patent/US265927A/en and http://patentimages.storage.googleapis.com/2f/61/6d/e3e3e1bb036e59/US265927.pdf · US174719 — https://patents.google.com/patent/[US174719A](/patent/US174719A)/en and https://patentimages.storage.googleapis.com/a7/2e/fb/01e2a178f3c421/US174719.pdf · 39 F. 25 — https://law.resource.org/pub/us/case/reporter/F/0039/0039.f.0025.pdf · 138 U.S. 124 — https://supreme.justia.com/cases/federal/us/138/124/ · 43 F. 527 — https://law.resource.org/pub/us/case/reporter/F/0043/0043.f.0527.1.pdf

C. § 102 mapping, claim by claim — and one legal caution

Caution on the statute: 35 U.S.C. § 102 in its modern form derives from the 1952 Act, which postdates this patent by 69 years; the novelty statute in force in 1882–83 was R.S. §§ 4886 and 4920 (with the two-year statutory bar). I have mapped to § 102 as you asked, but for a pre-AIA patent the correct operative subsections would be pre-AIA § 102(a) (known/used/patented before the applicant's invention) and § 102(b) (patented or described in a printed publication more than one year before filing) — and the "more than two years" version of the bar that then applied.

Claim 1 (frame + roll-shafts + end-to-end counter-shaft + pulleys + belts + means for adjusting both ends simultaneously):

• § 102 anticipation — US 265,927 (Marmon & Warrington, 1882‑10‑10). The court found "Upon the face of these two patents there appears to be an anticipation of the claim sued upon." Decisive because claim 1 is drafted in means language: "the patentee claims broadly any means of simultaneously adjusting both ends of the counter-shaft, and not specified devices… the drawing… shows 12 different devices for that purpose, which are thereby made equivalents of one another. It follows that, if the defendant would be guilty of infringement by using any means of simultaneous adjustment, plaintiff's patent would also be anticipated by the prior use of any such means."
• § 103-type (want of invention) — Clark 174,719 + Odell 250,954 + Lane & Bodley saw-mill. The court's words are functionally § 103, not § 102: "The means adopted are not dissimilar, and in our opinion there is nothing beyond mere mechanical skill required in applying these means to the counter-shaft of a roller-mill… it does not call for the exercise of the inventive faculty."
• Additional, separate ground — double patenting / same invention. The examiner's letter of 1882‑12‑22 refused claims 1–3 because "an application cannot receive protection in a separate application for matter which was described, claimed, sworn to jointly by himself and another, and jointly patented prior to the filing of the subsequent application." The court cited Sickles v. Falls Co., O'Reilly v. Morse, Odiorne v. Nail Factory, Smith v. Ely, and James v. Campbell, 104 U.S. 356. This is the "no two patents for the same invention" line, not classic § 102 art.

Claim 2 (the same combination narrowed to simultaneously adjustable boxes N): maps element-for-element onto claim 12 of US 265,927 ("the devices, N, the rods, O, and mechanism connecting said rods together"). Strongest § 102 showing of the set.

Claim 3 (adds the tunnel a in the frame for the counter-shaft): not separately discussed in the reported reasons. The examiner's refusal of claim 3 was on the same-invention ground as claims 1–2. No reference was shown to teach away the tunnel, and I cannot state a § 102 anticipation for claim 3 on this record.

Claims 4–6 (rods O / cross-shaft P / cross-shaft Q + worm gear, and "adjustable from the sides of the machine"): no prior art was adjudicated. Note the tension, though: claim 6's worm-gear P/Q is one of the 12 alternates the court treated as a mechanical equivalent of the Marmon & Warrington structure — so US 265,927 claim 12 plus the equivalence finding is the obvious line of attack, but it was not the basis of any holding.

Claims 7–8 (feed-gates J with rack-arms j / pinions K″; feed-gates I with rock-shafts I′ and stops i′): no prior art identified in the 274508 record. The feed art of record in the companion case is directed at a different patent (Dowling's agitator) and consists of Cains, US 78,423 and US 137,051 (seed/fertilizer drills), T. J. West, US 100,573, and H. E. Keeler, US 254,140 — all agitator/stirrer art, not rack-and-pinion gate art. I flag that these are not properly cited against claims 7–8.

Claims 9–10 (adjustable journal-boxes: toggles + securing bolts; swinging arms D + boxes E + toggles e + bolts e′): the closest art of record is the Gray/Nemelka family, developed at length in the related opinions — Nemelka's Austrian patents of 1875‑01‑15 and 1875‑05‑22, French patent of 1875‑06‑23, English patent to Lake No. 3,328 of 1877, and the Lake U.S. patent of 1878‑11‑12; plus Mechwart's Austrian patent of 1875‑08‑03 (belt drive). These show vertically/horizontally adjustable roll bearings, spring pressure regulation, and cams/screws/nuts — i.e., the same functional result as claims 9–10's toggle adjustment. But these references were applied against Gray's and Dowling's claims, not against 274508's claims 9–10, and I did not find any decision construing claims 9–10. Treat this as a "closest art" lead, not an adjudicated anticipation.

D. Google's "Similar Documents" list for US 274508 (algorithmic, not citations)

Offered for completeness and because one entry is substantively important. Dated as printed on the 274508 record:

US275055 (1883‑04‑03, Roller-mill) · US275835 (1883‑04‑17) · US277525 (1883‑05‑15) · US301020 (1884‑06‑24) · US457395 (1891‑08‑11) · US1403698 (1922‑01‑17) · US265927 (1882‑10‑10, "Roller mill") · US312048 (1885‑02‑10) · US348553 (1886‑09‑07) · US674718 (1901‑05‑21) · US269459 (1882‑12‑19) · US1027206 (1912‑05‑21) · US401243 (1889‑04‑09) · US280170 (1883‑06‑26) · US274210 (1883‑03‑20, Grinding-mill) · US339163 (1886‑04‑06) · US266490 (1882‑10‑24) · US284135 (1883‑08‑28) · US444348 (1891‑01‑06) · US467713 (1892‑01‑26) · US259480 (1882‑06‑13) · USRE10493E (1884‑06‑24) · US947669 (1910‑01‑25) · US1063463 (1913‑06‑03) · USRE10579E (1885‑04‑07).

The one that matters is US265,927 (1882‑10‑10) — the same document the Coombs court called the "prior patent to Marmon and one Warrington, dated October 10, 1882 — or about six weeks before the filing of the application for the Marmon patent." The date on Google's own page for 274508 matches the court's date exactly, and the specification's reference-letter scheme (D arms, E boxes, F tempering rods, G rods, H bar, I cam, J gates, K shafts, L bar, M counter-shaft, N adjustable devices, O rods, P shaft, pulleys 1–14) is the same family as 274508 but with "Our said invention" language — i.e., joint inventors. That is strong corroboration; the inventor names themselves are not visible in the face data I retrieved, so the Marmon‑and‑Warrington attribution rests on the court's opinion, not on the front page.

E. Two explicit flags

1. Apparent contradiction in the earlier sections — resolved. The patent summary quoted "Gray's prior patent, No. 228,525" while the litigation summary quoted "the Gray patent, No. 222,895." These are not the same patent and not in conflict: both numbers appear in the single Coombs opinion. 228,525 is Gray's belt-drive/counter-shaft patent (issued 1880‑06‑08) and supplies elements 1–5 of Marmon claim 1; 222,895 is Gray's roll-adjustment patent and was the patent in suit in Coombs — the only one on which the plaintiff won its injunction. The decree as reported is: injunction on the Gray patent, "the defendant is entitled also to have inserted therein a clause dismissing the bill as to the Dowling and Marmon patents."

2. Still unresolved: whether the "Marmon patent" in suit was 274,508 or a reissue. The opinions never print the Marmon number. USRE10493E (1884‑06‑24) appears on the 274508 record with an OCR-attributed name that reads like "harmon"; I could not verify in this session whether RE 10,493 is a reissue of 274,508. Until that is checked against the RE10,493 face page, all statements above are framed to the original patent 274,508, whose claims 1–3 are the ones the court addressed.

F. What I could not verify in this session

• US 250,954 (Odell) — grant date, inventor, and text: not retrieved (search budget exhausted). Its description here comes only from the Coombs opinion's characterization.
• The Lane & Bodley saw-mill device — no patent number or date is given in the opinion; it is prior-use evidence, not a documentary reference.
• The exact U.S. Reports cite for the Gray roll-adjustment appeal (the opinion text appears in U.S. Reports vol. 156, October Term 1894, per the Supreme Court's PDF at https://www.supremecourt.gov/pdfs/USReports/USREPORTS-156_PDFA.pdf and the Harvard scan https://storage.courtlistener.com/harvard_pdf/94092.pdf); I did not verify the page number.
• Any citation against claims 4–10 of 274,508. No such record exists in the sources searched. The invalidity holding is confined to claims 1–3 as presented, and to my knowledge claims 4–10 were never construed.

I'll ground the obviousness analysis in the actual prior-art record before building combinations.

Let me pull the remaining prior-art references from the page's Similar Documents list.

Obviousness Analysis — US 274,508 (Marmon, "Roller-Mill") under 35 U.S.C. § 103

Builds on: the Patent summary, Litigation summary, and PTAB sections already produced. I do not repeat the bibliographic or litigation narratives; I add the § 103 layer and flag two contradictions with earlier sections at the end.

0. Two threshold corrections before the analysis

(a) The "Prior Art" section of the Google Patents page is only one of three prior-art tiers. The page's structured prior-art content consists of the "Prior art keywords" field (arms, shaft, rolls, shafts, feed — an algorithmic extraction from the claims, not prior art) and the "Similar Documents" list of 25 references. For a § 103 analysis of an 1882 filing, the Similar Documents list is materially incomplete: it omits the references that actually killed the patent. I therefore use (A) the on-page list, (B) the art judicially established in the 1889–1895 Consolidated Roller-Mill litigation, and (C) the foreign printed publications relied on by the courts.

(b) "Prior art date 1883-03-27" on the page is the issue date, not a prior-art date. The operative cutoff is the filing date, 1882-11-27 (or Marmon's earlier date of invention if he could prove one). Only three references in the Similar Documents list were issued before that date: US259,480 (1882-06-13, "John m"), US265,927 (1882-10-10, "Roller mill"), US266,490 (1882-10-24, "Roller mill"). Everything else in that list issued 1883-04-03 or later and is available at best as § 102(e)-type art (US patent granted on an application filed before Marmon's invention date) — and I could not verify filing dates for those documents within my search budget. Treating post-filing issue dates as prior art would be an error, so I mark those references as "state-of-the-art evidence only" below.

(c) Legal frame. § 103 did not exist until the 1952 Act; § 103(a) (pre-AIA) governs this 1882 filing. The 19th-century analogue is the common-law "inventive faculty" test of Hotchkiss v. Greenwood, 52 U.S. (11 How.) 248 (1850). Modern framing: Graham v. John Deere Co., 383 U.S. 1 (1966) (scope/content, differences, PHOSITA level, secondary considerations) and KSR Int'l Co. v. Teleflex Inc., 550 U.S. 398 (2007) (predictable variation, known technique, finite number of predictable solutions, design incentive). Note that the 1889 court in Coombs reached claim 1 as anticipation (§ 102), not obviousness — the § 103 route below is an independent, fully sufficient alternative ground.

PHOSITA: a millwright/machine designer with several years' experience in belt-driven roller mills and general mill machinery (belt tighteners, gate mechanisms, journal-box adjusters), c. 1882, familiar with Gray, Odell, Poole, Birkholz, and European roller-mill practice.

1. Prior-art universe

Tier A — on-page Similar Documents (by issue date)

Tier B — art established as prior art in the litigation (the operative set)

Tier C — foreign printed publications (§ 102(b): all published >1 year before 1882-11-27)

• Mechwart, Austrian patent, 1875-08-03 — driving each roll of a pair by belt; tightening pulleys; shaft journaled directly in the machine frame; double mills with two pairs of rolls.
• Nemelka / Lake — Austrian 1875-01-15 and 1875-05-22; French 1875-06-23; English (Lake) 1878-02-28; US 1878-11-12. Swinging frame carrying movable roll; cam acting on the pivot; cams connected so as to be operated simultaneously by one shaft; spring loading; adjustable parallelism by sliding bracket.
• English patent No. 3328 of 1877 — cited by the examiner against Gray.

2. Claim 1 — the flagship combination

Claim 1 elements: (i) supporting frame; (ii) roll-shafts; (iii) counter-shaft end-to-end, substantially parallel to the roll-shafts; (iv) pulleys; (v) belts; (vi) means for adjusting both ends of the counter-shaft simultaneously.

Motivation to combine (specific and articulated):

1. The counter-shaft's belt-tightening function was expressly known. Gray 228,525 states the counter-shaft serves the "double purpose of reversing the motion of certain of the rolls, and of acting as a belt-tightener." US 274,508's own specification repeats: "When this shaft is raised or lowered it loosens or tightens the several belts." Once the shaft is the belt-tensioning element, moving both of its ends is the natural way to tension belts at both ends without skewing the shaft — a predictable variation of Gray.
2. A one-operation control for a multi-point adjustment was a recognized design desideratum, not a discovery. Gray 238,677 (1881) had already advertised moving "the rod K, which may be done from either side of the machine … all the eccentrics operated simultaneously … without destroying the adjustment"; Odell RE 10,189 had already claimed a single lever simultaneously adjusting rolls and gates. Commercial literature of the period advertises "A single lever movement simultaneously throws apart the rolls and stops the feed." Marmon entered an art where single-operation multi-point adjustment was the goal, not the achievement.
3. Known technique (KSR prong 2). Using one actuating shaft/crank with two gear or linkage take-offs to move two spaced points together is exactly Clark 174,719's coal-breaker mechanism (same broad field — the modern CPC class for US 174,719 is B02C, Crushing/pulverising, the same class assigned to US 274,508) and the ordinary machine-shop belt-tightener technique. Applying a known two-point simultaneous adjuster to a counter-shaft is "the improvement of one [device] by the technique of another."
4. Finite number of predictable solutions. The record shows the whole family: bevel-gear-and-screw (Clark), through-shaft-and-link (Odell), rod-and-rocker (Gray 238,677), cam-on-pivot connected by one shaft (Nemelka/Lake), rope-and-spool (Marmon's own sibling application US 276,440, filed 1882-10-31 — not prior art, but powerful evidence that the mechanism was a design choice and the function was the conceived contribution).

Conclusion: Claim 1 is obvious over Gray 228,525 in view of Odell 250,954/RE 10,189, further in view of Clark 174,719 and Mechwart 1875. Independently, it is anticipated by US265,927 (within-window, same subject matter, joint patent issued 1882-10-10) — the ground the 1889 court actually adopted.

3. Remaining claims — combination chart

OCR caveat carried forward from the Patent summary: claim 7's "the bars L, having all sub-" is displaced in the source text; claim 10's "ing-bolts e" is garbled. My readings above remain reconstructions.

4. Cross-cutting motivations (usable for any of the above)

1. The art had a recognized, closed list of problems. Barnard & Leas (43 F. 527) and The Roller Mill Patent (156 U.S. 261) both catalogue the same four required adjustments: 1) vertical/tram, 2) horizontal parallelism, 3) spring yield on tramp material, 4) spread-and-return without losing adjustment. A POSITA combining references that each solve one of four known problems is combining known elements according to known methods to yield predictable results (KSR).
2. The belt-drive conversion was itself old. Mechwart (1875) disclosed belt-driving each roll with tightening pulleys; Gray's claim 1 was held to evince "only the exercise of ordinary mechanical or engineering skill" (Consolidated Roller Mill Co. v. Walker, 138 U.S. 124, 132 (1891)). The counter-shaft as belt-tightener was therefore an established element by 1882, and improvements to it start from a low baseline of patentable difference.
3. Analogous arts beyond roller milling. Clark's coal-breaker and the Lane & Bodley saw-mill are both belt-driven size-reduction/woodworking machines using two-point simultaneous adjustment. A POSITA designing a two-ended counter-shaft adjuster would look to these. KSR expressly blesses drawing on "any need or problem known in the field."
4. Commercial pressure toward one-man, one-motion control. A mill floor with four belts at two ends of a machine creates a real ergonomic cost in re-tensioning; the record shows the industry repeatedly reached for single-lever control (Odell 1881; Gray 238,677 1881; Livingston 284,135, interference decided 1883-03-31 in Odell's favor). This is a design incentive with a predictable solution.

5. The strongest single combination, stated formally

Gray 228,525 + Odell 250,954/RE 10,189 + Clark 174,719 (+ Mechwart 1875 as background), optionally with Lane & Bodley and Nemelka/Lake.

• Gray supplies every element of claim 1's combination except simultaneity, plus the express disclosure that the counter-shaft is a belt-tightener.
• Odell supplies a single hand lever simultaneously adjusting a plurality of roll adjustments in the very same machine type through a through-shaft and link mechanism — including, in claim 4, simultaneously adjusting rolls and feed gates (which reaches claims 1 and 7 together).
• Clark supplies the two-point/single-input adjuster mechanism (crank → shaft → two bevel pairs → two screws) in a roll crusher, i.e., the "means for adjusting both ends … simultaneously" element.
• Mechwart/Lane & Bodley/Nemelka confirm that belt tensioning by shaft movement and simultaneous multi-point cam/lever operation were established techniques.

Result: claims 1–5 obvious; claims 7–8 obvious over Odell + Gray 235,761/Daverio; claims 9–10 obvious over Poole & Miller + Gray 222,895; claim 6 the only claim requiring a genuineness judgment on a single mechanical substitution.

6. Counterarguments and why they likely fail

7. Where I would not confidently predict obviousness on this record

• Claim 6 (worm gear between shafts P and Q). No reference in either the on-page list or the litigated art shows a worm/worm-wheel in a roll adjuster. My conclusion rests on general mechanical knowledge (worm drives as self-locking, high-reduction actuators) plus Clark's use of bevel gearing for the analogous take-off. That is a legitimate but weaker evidentiary footing. Claim 6 would more likely fall on double patenting / obviousness-type double patenting or on § 102 over a worm-geared counter-shaft adjuster not yet located. Do not cite a specific worm-gear prior-art reference without verifying it — I found none.
• Claim 3's "tunnel" limitation is a structural-routing element. I can show Gray's counter-shaft passes through the frame base, but I have not confirmed a prior-art casting with a formed tunnel through which the shaft passes end-to-end. The obviousness argument for this limitation is thinner and more argumentative.

8. Secondary considerations

• No long-felt need. The simultaneous-adjustment need was already met by Odell (1881) and Gray (1881) before Marmon's November 1882 filing. The commercial record shows roller mills converting from millstone technology industry-wide at that time, which undercuts any nexus-based commercial-success argument for this specific claim set.
• Copying by competitors (Barnard & Leas, Walker's Obenchain, the Livingston/Stout mill) is real but cuts both ways: the courts found those mills tracked the earlier Gray/Odell/Nemelka art rather than Marmon.
• Skepticism: none found in the record.
• Unexpected results: none asserted. Marmon's specification asserts only convenience ("This is much more convenient than the previous means … which have been operated from the ends of the machine by reaching over the belts") — a candid admission that the contribution is ergonomic and degree-only, which is precisely the Burt v. Evory, 133 U.S. 349 (1890) "improvement in degree is not invention" problem.

9. Contradictions with previously generated sections (flagged as required)

1. Gray patent number. The Litigation summary states the asserted Gray patent was "No. 222,895"; the Patent summary and PTAB sections state "No. 228,525." Both numbers exist and belong to different Gray patents litigated in different cases. Per the retrieved texts: Consolidated Roller-Mill Co. v. Barnard & Leas Mfg. Co., 43 F. 527 (C.C.N.D. Ill. 1890), aff'd 156 U.S. 261 (1895), concerned 222,895 (adjustment devices) and 238,677 (spread device); Consolidated Roller Mill Co. v. Walker, 43 F. 575, aff'd 138 U.S. 124 (1891), concerned 228,525 claim 1 (counter-shaft/belt drive). The § 103 analysis above is unaffected — I use 228,525 as the primary reference precisely because its claim 1 is the counter-shaft claim — but the earlier report's blanket attribution of "the Gray patent" to a single number is imprecise and should be corrected downstream.
2. Odell number and reissue number. The Litigation summary cites "Odell patent No. 250,954." The retrieved reporter text gives the original as granted December 1881 (OCR varies between "December 13" and "December 18") and the reissue as No. 10,189, June 20, 1882 — while one OCR instance renders it "10,139." Because the reissue claims (1, 2 and 4) are the ones actually at issue in Odell v. Stout, 22 F. 159, the reissue number should be verified before being cited. I use "250,954 / RE 10,189" with that caveat.
3. The Marmon patent number in Coombs. The Litigation summary correctly flagged that the retrieved Coombs opinion excerpt did not print the number. My targeted retrieval of the 39 F. 25 text confirms only the subject-matter identification — "the Marmon patent to the adjustment of the counter-shaft to tighten or loosen the belts at each end of the machine simultaneously" — which matches US 274,508 claim 1 exactly, but is still not a number recital. The uncertainty stands.
4. New finding not in any earlier section: the on-page Similar Documents list contains US276,440 is not in that list, but my search surfaced it — D. W. Marmon, "Roller-Mill," filed 1882-10-31, issued 1883-04-24, assignor to Nordyke & Marmon, claiming a different mechanism (spools/sheaves E, ropes F, shaft G, crank H) for the same stated object: "operating both ends of the counter-shaft of a roller-mill simultaneously." This is not prior art against US 274,508 (same inventor; and it post-dates in issue), and I do not use it as such. It is, however, important context: Marmon filed two applications a month apart, each claiming a different mechanism for one identical function — which is itself evidence that the function, not the mechanism, was the conceived contribution, and that the mechanism was a choice among known equivalents.

10. Bottom line

On this record, claims 1–5 are obvious over Gray 228,525 + Odell 250,954/RE 10,189 + Clark 174,719 (with Mechwart 1875, the Lane & Bodley saw-mill, and Nemelka/Lake as reinforcing art); claims 7–8 are obvious over Odell RE 10,189 + Gray 235,761/Daverio and Gray 222,895/238,677 respectively; claims 9–10 are obvious over Poole & Miller 238,001 + Gray 222,895 + Clark 174,719. Claim 6 (worm gear) is the only claim where I cannot point to a specific anticipatory or combinable reference for the recited gearing and must rely on general mechanical knowledge — flag that as the soft spot. The single most important caveat for any downstream user is temporal, not technical: the art that actually invalidated claim 1 did so as § 102 anticipation in 1889, and this § 103 analysis is a modern-law restatement of a holding that is already 137 years old.