US 292531

I'll run targeted searches for this specific patent number across USPTO sources and Federal Circuit dockets.

Search scope and what was/wasn't found

I searched for the literal identifiers 292531, US292531, US292531A, and 292,531 against USPTO/Google Patents sources and against Federal Circuit docket material.

• USPTO / patent record: found and confirmed — Google Patents record and the original patent PDF (patentimages.storage.googleapis.com/.../US292531.pdf).
• CAFC 2026 dockets: no results. I found no Federal Circuit docket, opinion, or appeal involving US 292531 (or US 292531A). This is expected: this patent issued in 1884 and its term expired in 1901 (Google Patents lists "Anticipated expiration 1901‑01‑29," status "Expired – Lifetime"). There is no live cause of action.
• One trap to flag: a search hit discussing "§ 292" refers to 35 U.S.C. § 292 (false marking), not to patent number 292,531. Unrelated — do not conflate.

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US 292,531 — summary

Abstract

There is no abstract. US 292,531 is an 1884 filing, predating statutory abstracts. The Google Patents "Definitions" field contains extracted text from the specification, not an abstract. The closest thing to a stated purpose is the specification's own statement of objects:

"The objects of my invention are, first, to provide every outside room of a building with a flexible ladder extending from the window‑sill to the street below, and arranged to be readily attached to the sidewalk or curbing of the street, and, secondly, to arrange a convenient receptacle for the ladder when it is not required to be used as a fire‑escape, and yet have the same where it cannot be misplaced or missing in case of need."

Plain-language overview of the disclosure

A flexible ladder (A) made of two flat side straps (a) of leather or metal. The rungs (b) are formed of strong wire passed through the straps, with the wire ends bent back and looped together, so each rung is "double." The upper end is fastened to an iron roller/shaft (f) journaled in a hollow box/receptacle (c) sunk into the window‑sill; the box is big enough to hold the coiled ladder, and a lid conceals it. A removable crank winds the ladder back up. The free lower ends of the straps carry snap‑hooks (d) that fasten into rings (e) set into the street curbing, so the deployed ladder forms a "gentle incline." In use, the occupant raises the window, opens the receptacle, drops the free end (it unwinds by its own weight), and hooks it to the curbing. Because the ladder foot anchors away from the building, descending persons are kept clear of flames/smoke from lower windows.

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Independent claims — plain language

Both numbered claims are independent (claim 2 does not refer back to claim 1). I quote the claim text literally, including the OCR artifacts present in the record.

Claim 1 — A fire‑escape ladder comprising:

1. two flat leather or metallic side pieces a a;
2. the side pieces attached to and rolled around a shaft or roller f;
3. that shaft/roller secured in a receptacle opening through the window‑sill;
4. the side pieces connected by a series of double wire rungs; and
5. the lower end of each side piece having attached "a snaphook" (rendered in the OCR'd text as "asnaphook") arranged to fasten in a ring secured to the curbing of the street — "all as described."

Claim 2 — A combination claim covering the assembled system: the shaft or roller f secured in a receptacle opening through the window‑sill and provided with a removable crank, taken together with the side pieces a a, the double wire rungs or steps b, the snap‑hooks d, and the attaching‑rings e secured in the street curbing, "all substantially as described."

Practical read: Claim 1 is directed to the ladder-plus-snap‑hook-plus‑sill‑roller subassembly; Claim 2 is the broader system claim adding the removable crank and the curbing-mounted anchor rings — i.e., the full window‑sill‑to‑curbing installation.

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Confidence and uncertainty notes

• High confidence on title, inventor name/residence, filing date (Oct. 2, 1883), issue date (Jan. 29, 1884), classification, and both claim texts — all taken directly from the patent PDF and Google Patents record retrieved above.
• No assignee found — I cannot confirm any assignment of record because none appears on the face of the document; I did not retrieve a chain‑of‑title/assignment record, so I state this as "none of record," not as proof that no assignment instrument exists.
• Do not trust the OCR dates in the body text. The specification header is OCR'd as "dated January 29, 1854" and "Application filed October 2, 188[3/4]"; the PDF OCR shows "dated January £9, 18£4" and "filed October 2,188." These are scan artifacts. The authoritative metadata is filed 1883‑10‑02, issued 1884‑01‑29.
• No CAFC 2026 activity exists for this number as far as my searches show; absence of results here is consistent with the patent's 1901 expiry and should not be read as a docket search that was merely incomplete — but I cannot rule out a non‑indexed or mis-docketed entry, and I found none.

I'll search for litigation involving US patent 292531.

Let me run a few more targeted searches on litigation databases.

Let me check a couple more specific sources.

Litigation Search Report — U.S. Patent No. 292,531

Bottom line

No litigation involving U.S. Patent No. 292,531 is known. I found no district court case, CAFC appeal, ITC investigation, or PTAB proceeding in which US292531 was asserted, challenged, or otherwise at issue.

Patent identification (as literally returned by the sources)

The patent covers a flexible ladder of two flat leather or metallic side pieces (a a) rolled on a shaft/roller (f) housed in a receptacle opening through the window-sill, connected by a series of double wire rungs (b), with snap-hooks (d) at the lower ends that fasten into rings (e) set in the street curbing. Two claims were issued (claim 1 to the ladder assembly; claim 2 to the combination of roller, removable crank, side pieces, double wire rungs, snap-hooks, and curbing rings).

Why no litigation appears

• The patent expired in 1901, before the modern federal docketing/electronic-records era. Any enforcement action would have been an 1880s–1890s equity suit in a circuit court, which is not indexed under the patent number in PACER, CourtListener, Unified Patents' Portal, or comparable databases.
• Google Patents lists only one "Cited By" entry for US292531 — US5064021A, "Window escape" (Bauer Ronald F, filed 1990-04-20, granted 1991-11-12). That is a prior-art citation made during prosecution of a later application, not litigation. I found no indication US5064021 ever asserted or relied on US292531 in a lawsuit.
• The only other documents referencing the string "292531" that my searches surfaced are different patents and unrelated matters, which I am flagging so they are not conflated with US292531:
  • JP H09-292531 (Kalantar et al., light guiding plate) — a Japanese publication cited as Ex. 1006/1007/1008 in the petition for IPR2015-00757 concerning U.S. Patent 7,914,196.
  • JP 2004-292531 A (Asahi Kasei, flame-retardant polyamide resin composition).
  • Several hits on "292" alone, which refer to 35 U.S.C. § 292 (false marking) — a statute, not this patent (e.g., the Forest/Bon Tool false-marking case discussed at cdn.patentlyo.com).

Search record

Queries run and principal results:

1. 292531 patent litigation → PTAB IPR2015-00757 petition (JP H09-292531 reference), Google Patents US292531 page. No litigation.
2. "292531" patent case docket → same, plus JP 2004-292531 and US5037116 (unrelated). No litigation.
3. unifiedpatents.com litigation US292531 → Unified Patents RPI/IPR briefs (Dolby v. Unified; RPX/AIT; JustService; MCOM IP) — none mention US292531.
4. "US 292,531" OR "US292531" patent infringement lawsuit Bartlett fire-escape ladder → only the Google Patents page. No complaint, verdict, or docket.
5. US292531A "fire-escape ladder" litigation CAFC PACER → only the Google Patents page, plus an unrelated Ninth Circuit brief on the Pauly/Pray ladder patents. No US292531 case.
6. Unified Patents portal caselist patent 292531 and "292,531" patent infringement complaint district court → tool step limit reached; not completed.

Confidence and caveats

• I have high confidence that US292531 is a long-expired 1884 patent and moderate-to-high confidence that it has no recorded litigation in searchable modern databases (PACER, CourtListener, Unified Patents Portal, CAFC records).
• I cannot rule out pre-1901 enforcement actions documented only in print reporters or unindexed archival records; such records would not be retrievable by patent-number search. I also did not complete the final two searches above.
• No case number, filing date, jurisdiction, plaintiff, or defendant can be supplied, because none exists in the available record. I will not fabricate a docket entry to fill those fields.

If you want, I can re-run the Unified Patents Portal caselist and PACER/CourtListener queries for the bare number 292531 (as opposed to the patent) to confirm whether any unrelated case bears that docket-number fragment.

I'll verify the structured data with a web search before finalizing.

Proceedings overview

Total AIA trial proceedings on file: 0 — none, ever. The USPTO Open Data Portal returns no IPR, PGR, or CBM proceeding for US 292531, and web search surfaces no PTAB trial, no Final Written Decision, no institution decision, no settlement, and no Federal Circuit appeal involving this patent. The breakdown is therefore 0 active / 0 claims invalidated / 0 claims sustained / 0 settled / 0 institution-denied. The bottom-line defensive posture is unusual: there is no PTAB record at all, not because the patent is "hardened" by surviving challenges, but because it expired on 1901-01-29 (17 years after the 1884-01-29 grant), roughly 111 years before the AIA created the IPR/PGR/CBM regimes on 2012-09-16. There is nothing for a defendant to attack at the PTAB and nothing for a patent owner to defend.

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Individual proceedings

None to report. To be explicit about the negative finding rather than leaving it implied:

No proceedings found — not "sealed," genuinely absent

• Type: N/A (no Inter Partes Review, Post-Grant Review, or Covered Business Method review docketed)
• Filed: N/A
• Status: No PTAB proceeding exists; the patent's own legal status is recorded on Google Patents as "Expired - Lifetime," with an "Anticipated expiration" event dated 1901-01-29 (US292531A on Google Patents).
• Judge panel: None assigned. No APJ has ever touched this patent's claims.
• Petition grounds: None. No § 102, § 103, or § 112 ground has ever been pleaded against claims 1 or 2 in a PTAB trial.
• Institution decision: None. No § 314(a) or § 324(a) institution analysis exists.
• Final Written Decision: None. Neither claim 1 nor claim 2 has been construed, canceled, or upheld by the Board. Claims 1 and 2 remain as granted — untested and untouchable for other reasons.
• Settlement / termination: N/A.
• Appeal: No appeal to the U.S. Court of Appeals for the Federal Circuit. No CourtListener or CAFC docket entry exists for this patent.
• Defensive value: Zero PTAB-based defensive value, because the patent is not a live assertion target. A defendant receiving a demand letter citing US 292531 should treat the letter itself as the red flag — the patent expired in 1901 and cannot be infringed or enforced today, so any licensing demand grounded on it is baseless on its face.

One item worth pre-empting, because it looks like a proceeding and isn't: Google Patents lists a single forward citation, US5064021A — "Window escape," Bauer Ronald F, priority 1990-04-20, granted 1991-11-12. That is a later patent citing 292531 as prior art. It is not a PTAB proceeding, not an inter partes challenge, and not an adverse action against 292531. It does not appear in the PTAB docket and did not narrow or invalidate any claim. Searches for "292531" in a PTAB context also return unrelated foreign documents — e.g., JP H09-292531 (Nihon Denyo, light guiding plate) and JP 2004-292531 (Asahi Kasei, flame-retardant polyamide) — which share only a coincidental numeric string and have no connection to this patent. Do not let those citations migrate into a diligence memo as "IPR activity."

Strategic summary

Claim status: claims 1 and 2 are UNTESTED and, more importantly, EXPIRED. Claim 1 covers a fire-escape ladder with two flat leather or metallic side pieces (a a) rolled around shaft/roller f in a receptacle opening through the window-sill, connected by a series of double wire rungs, with a snaphook on the lower end of each side piece fastening into a ring in the street curbing. Claim 2 is the combination claim adding the removable crank with the side pieces a a, double wire rungs b, snaphooks d, and curbing rings e. Neither claim has ever been narrowed or canceled by the Board — but neither has any remaining term. The statutory 17-year term from the 1884-01-29 grant ran out on 1901-01-29 (that date is what the ODP/Google Patents "Anticipated expiration" event records). No claims are canceled, no claims are sustained through adversarial testing, and all claims are moot. There is no "surviving claim set" in any meaningful sense.

Estoppel landscape: inapplicable. Section 315(e)(2) estoppel only attaches to a petitioner after a final written decision, and no petitioner exists here. There is no estoppel bar, no § 315(b) one-year clock running against anyone, and no § 325(e) estoppel. Conversely — and this is the practical point — a defendant cannot affirmatively use the IPR regime either: while IPR is technically available for pre-AIA patents, an expired patent with no live infringement exposure gives a would-be petitioner no § 315(a)/(b) standing hook and no litigation or licensing posture to justify the filing fee, and PTAB institution of a trial on an 1884 patent is not a realistic outcome. Practically, an accused infringer's defense is not "invalidity at the PTAB" — it is the expiration date, which is a complete defense.

Pattern signals: none. There is no repeating petitioner (no Unified Patents, RPX, or other defensive aggregator has ever filed against this patent — the absence of any such filing on a 141-year-old patent is expected, not suspicious). The patent owner has not pursued any PTAB appeal because there was never a PTAB decision to appeal. The only "activity" in the record is a single forward citation from a 1991 window-escape patent, and a batch of "Similar Documents" from the 1876–1900 era (e.g., US194082, US263952, US331736, US444607) that reflect dense contemporaneous art in fire-escape ladders — but that art was never deployed in an AIA trial.

Recommended next steps

• If you are a defendant: you do not need PTAB strategies. There is no FWD to link to and no disposition to quote, because no proceeding was ever filed. Your dispositive argument is the term. State plainly that US 292531 issued 1884-01-29, expired 1901-01-29, and is recorded as "Expired - Lifetime" (source). A patent that expired in 1901 cannot be infringed, so any demand letter citing claims 1 or 2 is facially meritless — consider fee-shifting and state bar / unfair-competition exposure for the sender rather than an IPR petition.
• If you are asked to opine on PTAB risk in diligence: say "no AIA trial activity on file" — that is the accurate, citable answer. Do not characterize the 0-of-0 record as "the patent has survived challenges"; surviving a challenge requires that a challenge was filed.
• If active proceedings were pending: they are not, so no institution deadline, no oral hearing date, and no statutory one-year FWD clock apply. Should that ever change, the primary verification sources are the USPTO PTAB E2E / Patent Trial and Appeal Board Docket and the ODP API, with Federal Circuit dispositions at CourtListener and the CAFC docket.
• Caveat on my confidence: my search coverage of PTAB filings for a patent this old is necessarily indirect (Google Patents shows no PTAB proceedings tab content for US292531A, and my searches returned only unrelated same-number documents). But given the 1901 expiration and the 2012 creation of AIA trials, I am confident the correct answer is zero proceedings. If you need a belt-and-suspenders confirmation for a filing, pull the ODP API record directly and confirm the empty proceedings array, since that is the canonical structured source per your instructions.

I'll verify the assignment record before writing anything. Let me run targeted searches.

Search outcome up front

I ran the ownership-chain check on US 292,531 and found no recorded assignments to reconstruct. Because that is itself the finding, I'm stating it plainly here and then rendering the remaining required sections as explicitly-empty rather than omitting them — the deliverable stays complete and machine-parseable, but nothing below should be read as an assignment I found.

Sources checked:

• USPTO Assignment Center — https://assignmentcenter.uspto.gov/ (searched by patent number 292531)
• Google Patents legal events for US292531A — https://patents.google.com/patent/[US292531](/patent/US292531)/en
• Google Patents "Cited By" / family / similar-documents panels

Two corrections to the task framing, flagged as required:

1. The URL in the task prompt is stale. Per a USPTO notice surfaced in my search, as of February 2, 2026 the legacy URLs assignments.uspto.gov and assignment.uspto.gov are retired; Assignment Center at https://assignmentcenter.uspto.gov/ is the sole public entry point. Anything citing the old pair of URLs as "both surface the same records" is now wrong on the URL and right on the substance.
2. Coverage window problem. USPTO's assignment index (AOTW / Assignment Center) is generally described as containing recorded assignments submitted since August 1980, with pre-1980 conveyances held on microfilm/paper reels that are not reliably in the electronic index. US 292,531 issued January 29, 1884 — roughly 96 years before the electronic index begins. So "no records" here is weak evidence of "never assigned" and strong evidence of "nothing findable electronically." I cannot distinguish the two, and I will not pretend otherwise.

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Inventors

Unusual-pattern check: the classic red flag here would be "all inventors departed the original assignee within 12 months of filing." Not applicable and not testable. There is no original assignee to depart from, no employment relationship on record, and a single-inventor, no-model 1883 filing in a rural Oregon locality. This is the archetypal pre-corporatization individual inventor filing, not a distressed-portfolio fact pattern.

One inconsistency to flag against the prior section: the earlier-generated summary states the inventor resided at "Elk Flat, county of Union, State of Oregon." The authoritative patent text supplied to me renders only "Elk Flat, Oregon" with the county field OCR-garbled ("or ELK FLAT, o'nneov"). I cannot confirm "county of Union" from the authoritative source text and am carrying it forward only as an unverified prior-section assertion. The state (Oregon) and locality (Elk Flat) are confirmed.

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Original assignee

None of record. The patent issued in the name of the individual inventor, Andrew J. Bartlett, with no assignee named on its face and no assignee in the Google Patents bibliographic data. This is stated as "none of record," not as proof that no assignment instrument was ever privately executed — see the coverage-window flag above.

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Assignment timeline

The USPTO Assignment Center has no recorded assignments for US 292,531. There is no reel/frame to cite, no conveyance type, no assignor, no assignee, and therefore no correspondent of record — which means the single most useful NPE tell (the repeat-player recording attorney) is unavailable for this patent. Correspondingly, no shell-entity, no LLC, and no asserter appears anywhere in the chain, because no chain exists in the index.

Per the task instruction, the honest answer is to stop here. The remaining sections follow with explicit empty findings so the record is unambiguous.

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Timeline diagram

timeline
    title Ownership of US 292531
    1883 : Application filed by Andrew J Bartlett
    1884 : Patent issued to Bartlett
    1901 : Patent term expired
    1980 : Electronic assignment index begins
         : No assignments of record

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NPE / troll-pattern signals

Every signal is assessed against an empty record. None can be marked "present," and none can be marked a clean "not present" either, because absence of data is not absence of conduct — it is the 1980 index boundary.

Cross-references performed and their results: Google Patents legal events (no assignment entries — only application granted, publication, anticipated expiration); USPTO PEDS/ODP (no live record; term long expired); SEC 10-K/8-K (no public-company assignor or assignee exists to search); RPX and Unified Patents asserter directories (no entry for US 292,531 or Andrew J. Bartlett). The single "Cited By" reference, US 5,064,021 A (Bauer, "Window escape," 1991-11-12), is a later citing patent — it is not an assignment and does not place any Bauer entity in this chain.

Carried-forward trap, restated: a search hit discussing "§ 292" refers to 35 U.S.C. § 292 (false marking) and is unrelated to patent number 292,531. Do not conflate.

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Verdict

Insufficient data (no records, or only the original assignment).

The USPTO Assignment Center returns no recorded assignments for US 292,531, and Google Patents lists only three legal events for the patent — grant in 1884, publication, and anticipated expiration on 1901-01-29 — with no conveyance entries at all. With no reel/frame, no assignee, and no correspondent of record anywhere in the chain, there is nothing on which to base an NPE finding, and the patent predates the electronic assignment index by roughly 96 years, so the null result cannot be upgraded to a definitive "never assigned." There is likewise no live cause of action: the patent is Expired – Lifetime, so no 2026 Federal Circuit or district court activity can exist.

Verify at: https://assignmentcenter.uspto.gov/ (search patent number 292531). Note the legacy assignment.uspto.gov / assignments.uspto.gov pair is retired as of 2026-02-02.

I'll verify the citation record for US 292,531 directly before characterizing its prior art position.

The record for US 292,531 has no "Citations" section — I need to confirm that and pin down the contemporaneous references. Let me check the key candidates.

Bottom line first

US 292,531 has zero backward patent citations of record. I verified the record for the literal number 292531 / US292531A and there is no "Citations" / "References Cited" section at all on the Google Patents record — only a "Cited By (1)" block and a "Similar Documents" list. Those two things are routinely conflated with "citations," and they are not:

• "Cited By" = forward citations (later patents citing US 292,531). Under § 102 this runs the wrong direction — a 1991 patent cannot be prior art against an 1884 patent.
• "Similar Documents" = an algorithmic similarity ranking, not a citation relationship. Google Patents does not represent that US 292,531's examiner or applicant ever cited any of them.

This is expected for an 1884 patent: printed "References Cited" lists on US patent front pages did not become standard practice until decades later. So the honest answer to "look at each patent citation for 292531" is: there is exactly one patent-citation relationship in the record, it is a forward citation, and the reference roles are reversed.

I therefore do two things below: (A) dispose of the one real citation, and (B) supply the best-available candidate prior art from the contemporaneous corpus, clearly labelled as not citations of record.

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A. The only citation relationship of record — and why it is not prior art to US 292,531

Description. Bauer's 1991 window escape is a modern building-egress apparatus. Its significance here is purely evidentiary: a late-20th-century applicant's own citation list treated Bartlett's 1884 sill-receptacle/rolled-ladder disclosure as relevant background art.

§ 102 analysis — will it anticipate US 292,531? No. Categorically not.

• US 5,064,021 issued 1991-11-12, roughly 107 years after US 292,531 issued (1884-01-29). A reference cannot anticipate an earlier patent; anticipation requires the reference to predate the applicant's invention and filing. US 5,064,021 postdates US 292,531's filing (1883-10-02) by 106 years and therefore is not "prior art" to it under any subsection of pre-AIA § 102 (or under the 1870 Act then in force).
• The citation belongs to the other direction: US 292,531 is prior art against US 5,064,021, not the reverse. For US 5,064,021 it would be § 102(b)-type art (issued/printed more than one year before 1990-04-20).

Verdict: 0 claims of US 292,531 anticipated. Do not list this as prior art to 292531 — it is the converse.

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B. Candidate prior art (identified by similarity and by my own search — not citations of record)

B.1 Framing: which § 102 law actually governs, and what the critical date really is

US 292,531 was filed 1883-10-02, so pre-AIA § 102 is the only relevant framework (the AIA's first-inventor-to-file provisions apply to applications filed on or after 2013-03-16).

Two precision points that matter for an 1883 filing:

1. The statutory bar then in force was Rev. Stat. § 4886 (Act of 1870), not § 102(b) as we know it. Under the 1870 Act, a patent was barred if the invention was "patented or described in any printed publication" before the applicant's invention, or in public use / on sale more than two years before the application. The familiar one-year grace period for patents and printed publications was a 1939 addition (effective 1940). (Moderate-high confidence on this historical point; worth verifying against the statute text if it is load-bearing.)
2. Consequence: for a 19th-century filing there is effectively no one-year cushion for a printed publication. Anything printed/published before Bartlett's invention date is available. In practice I use 1883-10-02 (the filing date) as a conservative proxy, and I separately flag items before 1882-10-02 because they clear even the modern § 102(b) one-year bar.

Claim 1 requires all five elements to anticipate: (i) two flat side pieces of leather or metal; (ii) attached to and rolled around a shaft/roller; (iii) the roller secured in a receptacle opening through the window-sill; (iv) a series of double wire rungs; (v) snap-hooks at the lower ends fastening into rings secured in the street curbing. Claim 2 adds the removable crank and the curbing rings as a combination.

(Reminder carried over from the earlier section: the "§ 292" search hits refer to 35 U.S.C. § 292 false marking, not to patent 292,531. Unrelated.)

B.2 Google Patents "Similar Documents" for US 292531A — dates verified from the record

Split by whether the reference predates US 292,531's 1883-10-02 filing. Only Category 1 can be prior art.

Category 1 — predates the 1883-10-02 filing (usable prior art):

Category 2 — postdates the filing; cannot be prior art to US 292,531 at all:

US 286,519 A (1883-10-09) · US 303,055 A (1884-08-05) · US 308,334 A (1884-11-18) · US 331,489 A (1885-12-01) · US 331,736 A (1885-12-01, "Fire-escape ladder") · US 338,843 A (1886-03-30) · US 386,253 A (1888-07-17) · US 444,607 A (1891-01-13, "Fire-escape ladder") · US 482,274 A (1892-09-06) · US 653,498 A (1900-07-10).

Note the two post-dating patents actually titled "Fire-escape ladder" (US 331,736; US 444,607). These are not prior art to 292,531 — if anything they are later entrants in the same field. Do not present them as anticipating references.

B.3 Ranked candidates — full citations, dates, descriptions, § 102 verdict

① US 113,311 — Laynor & Helmling, "Improvement in Fire-Escapes," Apr. 4, 1871 (strongest structural analogue; found by my search — NOT on the Google similarity list, and NOT a citation of record)

• Full citation: Improvement in Fire-Escapes, US Letters Patent No. 113,311, granted Apr. 4, 1871, to George Laynor and Harry Helmling, of Baltimore, Md. URL: https://patentimages.storage.googleapis.com/75/e8/61/90b69d45ac3e02/[US113311](/patent/US113311).pdf
• Description (retrieved text): A window-sill constructed as a box (a, preferably iron) with a hinged cover (b) and a hinged front side (c) that turns down; a rod d journaled lengthwise within the sill-box carries the uppermost pair of ladder tie-pieces f; the ladder is built of rounds g joined by flat tie-pieces f, foldable into the sill, and is stored inside the sill when not in use. Arms h/rod h' hold the unfolded ladder off the wall of the building when dropped.
• § 102 relevance: This is the closest thing in the corpus to Bartlett's claim 1 element (iii) — a receptacle built into and opening through the window-sill that stores a ladder, with a hinged closure. It also overlaps the "keep clear of the wall" idea Bartlett claims as an advantage.
• Anticipation verdict: Does not anticipate claim 1 or claim 2. Laynor's ladder is folding/jointed (rounds + flat tie-pieces on a pivot rod), not rolled around a shaft/roller; there is no double-wire rung construction, no snap-hooks, no curbing rings, and no removable winding crank. It is, however, the best § 103 primary reference for the sill-receptacle-stored-ladder concept, and would combine well against claim 1 element (iii).
• Caveat: the OCR of this document garbles the date line ("No. 18811. Tainted Art, 4, 1891") while the body text reads "dated April 4, 1871." Verify the grant date against the USPTO copy before relying on the § 102 date.
• Note: I did not find US 113,311 cited anywhere in the 292531 record; its inclusion here is my own prior-art search, not the record's.

② US 241,509 A — Joseph Payne, "Fire-escape," May 17, 1881 (on the similarity list; full text retrieved)

• Full citation: Fire-escape, US 241,509 A, granted May 17, 1881 (application by Joseph Payne). URL: https://patents.google.com/patent/[US241509A](/patent/US241509A)/en
• Description (retrieved text): An iron frame-work with bars A/B/C and oblique double braces D, attachable to a building — one embodiment is "used in the lower part of a window … its lower part is so constructed as to fit the window-sill." A rope-and-pulley system lowers a collapsible bucket/sack with elliptical top and bottom rims; claims are directed to the frame of support, the lowering device (prongs J pivoted at K with spring), and the bucket.
• § 102 relevance: Adds only evidence that frame/receptacle hardware fitted to a window-sill for escape purposes was known.
• Anticipation verdict: Does not anticipate claim 1 or claim 2. It is a rope-and-bucket descender, not a ladder; there are no side pieces, no roller-mounted flexible ladder, no wire rungs, no snap-hooks, no curbing rings, no crank. Cite only as background art on sill-mounted escape hardware.

③ US 194,082 A — "Improvement in fire-escapes," Aug. 14, 1877 (on the similarity list; text not retrieved)

• Full citation: US 194,082 A, granted 1877-08-14. (Google Patents record.)
• § 102 date status: 1877-08-14 — clears even the modern § 102(b) one-year bar by ~6 years. Solidly citable.
• Anticipation verdict: Unknown / cannot state. I did not retrieve the specification or claims. Given the "Improvement in fire-escapes" titling convention of that era and the surrounding art (e.g., US 194,192 Tixier, US 194,443 Knowlton, US 194,507, US 194,625 — all 1877 siblings, all rope/cylinder-descender or extension-ladder devices), it is likely a descender rather than a rolled flexible ladder, but I will not assert that. Flagged as unverified; retrieve the PDF before relying on it.

④ US 263,952 A — "Fire escape," Sep. 5, 1882 (on the similarity list; text not retrieved)

• Full citation: US 263,952 A, granted 1882-09-05. Clears the modern § 102(b) bar by ~13 months.
• Anticipation verdict: Unknown / cannot state. Specification not retrieved. Same caveat as ③.

⑤ US 119,161 A — "Improvement in fire-escape ladders" (title directly on point; date not verified)

• Full citation: US 119,161 A. Publication date not verified in my searches — the number sequence places it in the early 1870s, but I will not guess a date.
• Anticipation verdict: Unknown. The title is the single most on-point title in the whole similarity set ("fire-escape ladders"), which makes it the highest-value unexamined reference here. Priority retrieval target.

⑥ US 285,806 A — "Fire-escape," Oct. 2, 1883 (on the similarity list; notable coincidence)

• Full citation: US 285,806 A, granted 1883-10-02 — the same date Bartlett filed (1883-10-02).
• Why it matters: (a) It sits exactly on the boundary — as a publication it is not "before" the filing date, so it is not cleanly available; its availability would instead turn on whether its invention predates Bartlett's, i.e., an interference/priority question, not a § 102 printed-publication rejection. (b) It is itself one of the 12 references cited in US 5,064,021, alongside US 292,531 — the two appear side by side in a 1991 citation list.
• Anticipation verdict: Not available as § 102 art on the dates alone. Do not present it as anticipating.

B.4 Incidental finds that are different patent numbers — filtered out, not conflated

Per your instruction to return only the specific number 292531, I excluded these numbers that surfaced in my search results: US 146,768 (Loeffler, 1874), US 193,176 (Palatini, 1877), US 194,192 (Tixier, 1877), US 194,443 (Knowlton, 1877), US 194,507 (1877), US 194,625 (1877), US 273,807 (Braunfeld, 1883), US 277,433 (Todd & McKee, 1883), US 285,603 (Fell, 1883), US 286,306 (Johnson, 1883), US 290,254 (McCandliss, 1883). None is US 292,531, and none appears in the 292531 record. Substantively they are friction-rope descenders and reel-governor devices, not flexible ladders — so even as candidate art they do not touch claim 1's (i)–(v) elements. I list them only so you can see what was excluded and why.

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C. Consolidated § 102 verdicts

No located reference, cited or uncited, anticipates either claim of US 292,531. The apparent point of novelty — the combination of a flexible rolled ladder on a sill-mounted roller with snap-hooks anchoring into rings set in the street curbing so the foot stands off from the building — does not appear in any reference I located. The nearest structural hit (Laynor, US 113,311) supplies the sill-box receptacle but a folding, not rolling, ladder, and nothing at all on the curbing-ring anchor.

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D. Confidence and limits — read before relying on Section B

• High confidence, verified from the record: the absence of any backward-citation section; the existence and direction of the US 5,064,021 citation; US 5,064,021's dates; and every date in the "Similar Documents" tables (taken directly from the Google Patents record for US292531A).
• Medium confidence: the 1870-Act statutory-bar framing (Rev. Stat. § 4886; no one-year grace for printed publications in 1883). Correct to my knowledge, but verify against statute text if load-bearing.
• Low confidence / explicitly unverified: the substance of US 194,082 A, US 263,952 A, US 119,161 A, and every other similarity-list entry whose full text I did not open. I have not read those specifications or claims, so my "cannot anticipate" or "unknown" calls for them rest on dates and titles, not on element comparison. Several titles in the record are OCR-mangled ("Charles f," "James pappa," "Geoege m," "Teeeitoet," "John stephen manuel willcox") because Google extracted inventor fragments as titles — those are not reliable titles.
• Provenance warning: everything in § B is candidate prior art assembled from Google Patents' similarity ranking plus my own searches. None of it is a citation of record for US 292,531, and none of it should be described as such. If you need the authoritative citation set, the correct conclusion is that the 1884 record contains no cited references — a front-page "References Cited" list did not exist for this patent.
• Recommended next steps if this needs to be airtight: (1) pull the USPTO Patent Public Search / PatentCenter copy of US 292,531 to confirm the printed front page carries no reference list; (2) retrieve full texts of US 119,161 A, US 194,082 A, and US 263,952 A, which are the three highest-value unexamined candidates; (3) verify the US 113,311 grant date against the official copy, since its OCR date line is corrupt.

I'll pull the actual disclosures of the pre-1884 references from the page's Prior Art/Similar Documents section before building any combination theory.

Let me try to pull the actual disclosures for the remaining pre-1884 references on the page.

Obviousness Analysis — US 292,531 (Bartlett, Fire-escape ladder)

Task framing: assess validity of claims 1 and 2 under 35 U.S.C. § 103, using the references listed in the Prior Art / "Similar Documents" section of the US292531 Google Patents page, plus the page's own "Cited By" entry.

Bottom line up front: the page's listing gives me a strong anchorage theme (securing an escape appliance to the window-sill / to a fixed hold) and a strong portability/handling theme, but I could not verify a single listed reference that discloses the two most specific limitations of claim 1 — the double wire rung (wire passed through the strap, ends bent back and looped together) and the snap-hook-into-curbing-ring combination. So the honest § 103 verdict is: claim 2 is highly vulnerable as a mere aggregation of old elements; claim 1 is only vulnerable if art outside the page's listing is added to the record. Details and caveats below.

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1. Two threshold flags before any § 103 reasoning

(a) § 103 did not exist on 1884‑01‑29. US 292,531 issued under the Act of 1870 (R.S. §§ 4886, 4920). The statutory "obviousness" defense arrived with § 103 of the 1952 Act. The contemporaneous doctrine was the "invention" requirement — Hotchkiss v. Greenwood, 52 U.S. (11 How.) 248 (1850) (the "ordinary mechanic" standard that Graham v. John Deere later identified as § 103's ancestor), and the aggregation‑vs‑combination line: Hailes v. Van Wormer, 87 U.S. (20 Wall.) 353 (1874), and Pickering v. McCullough, 104 U.S. 310 (1881) (union of old elements that produces no new cooperative result is a mere aggregation and not patentable). Everything below is therefore a modern-§ 103 analysis applied retroactively, and I note where the 1884 standard would have been more forgiving to the patentee (the pre‑1952 "invention" bar was nominally higher, and Cuno‑era "flash of genius" rhetoric did not arrive until 1941 — later abrogated by § 103 and KSR).
Medium confidence on the exact holdings as I state them; the case names and dates are ones I am confident about, but if this analysis is going into a formal paper, verify each citation.

(b) The "Cited By" entry is NOT prior art. The page lists US 5,064,021 A (Bauer, "Window escape," 1991‑11‑12) — a forward citation. It post‑dates US 292,531 by 107 years and cannot be § 102/§ 103 art against it. A careless reading of "the Prior Art section of this page" could sweep it in; it must not be.

(c) Prior-art cutoff date. Google lists "prior art date 1884‑01‑29" — that is the issue date, i.e. the date US 292,531 became a reference against others. For screening art against Bartlett, the operative date is the filing date, 1883‑10‑02 (or his invention date, which is not of record). Using 1884‑01‑29 would wrongly admit four extra documents.

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2. Eligibility screen of the 25 listed "Similar Documents"

Twenty-five documents are listed. Applying the 1883‑10‑02 cutoff:

Cautions on that table:

• US 285,806 is dated exactly 1883‑10‑02 — the same day Bartlett filed. Depending on whether one uses the filing date or an earlier invention date, it is either simultaneous art or not art at all. It cannot be resolved without its own filing/issue metadata, which I did not retrieve.
• Several "post‑filing" entries (e.g. US 308,334, US 331,736/US 331,489) could still be citable as pre‑AIA § 102(e) art if their applications were filed before Bartlett's invention date. I did not verify their filing dates, so treat them as excluded but not irrebuttably so.
• The list is a Google similarity ranking, not a legal search. It is heavily weighted by CPC class A62B1/00, which is why it is densely populated with rope‑friction descender patents — a different sub-genre from Bartlett's flexible rung ladder.

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3. Verification status — what I could actually read

I attempted to retrieve the text of the listed references. Results:

This is the central limitation of the analysis and I am stating it up front rather than papering over it: for 11 of the 13 pre‑filing references I have only the title and date from the page. Any element‑by‑element mapping below that relies on them is conjectural and must be confirmed against the reference texts before being relied on.

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4. Element-by-element analysis

Claim 1 requires, in combination: (i) two flat leather or metallic side pieces a a; (ii) attached to and rolled around a shaft/roller f; (iii) the shaft secured in a receptacle opening through the window‑sill; (iv) side pieces connected by a series of double wire rungs b; (v) lower end of each side piece carrying a snap‑hook d fastening into a ring e set in the street curbing. Claim 2 adds the removable crank and recites the whole set as a combination.

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5. Combination theories

Theory A — Holthausen + Phillips: sill anchoring + portable rescue appliance

Combination: US 181,577 (grooved friction block; rope fastened to the window‑sill "or other secure hold"; controlled descent) with US 202,460 (Phillips' portable, "conveniently handled" building‑rescue device).
Motivation: both references are in the same field (A62B 1/00 — lowering persons from buildings) and address the same problem: getting occupants of upper stories to the ground quickly with apparatus that is at hand and easy to handle. Holthausen supplies the express teaching that the descent tackle is fixed at the window‑sill, which is precisely where Bartlett mounts his roller.
Coverage: supplies element (v)'s concept of a fixed sill anchor and the general motivation, but supplies none of the ladder structure, the double rung, the roller, the sill receptacle, or the curbing hook‑and‑ring.
Assessment: insufficient standing alone. Useful only as the motivation leg of a larger combination.

Theory B — Hoyt (US 193,841) + the flexible‑ladder art: adaptable fire‑escape ladders

Combination: the portable extension‑ladder‑as‑fire‑escape of US 193,841 with whatever listed reference first discloses a flexible strap ladder (candidate: US 241,509, 1881; or US 266,062, 1882 — both unread).
Motivation: a worker in this field, seeking a fire‑escape that reaches from any upper window to the street, would look to ladder art generally; Hoyt shows the design choice between a rigid extension ladder (bulky, needs firemen) and something permanently available to the occupant. Making the ladder flexible so it can be coiled and kept in the sill is the predictable next step once storage is the design constraint.
Assessment: plausible but unverified on both legs. Theory B collapses if none of the listed references discloses a flexible strap ladder.

Theory C — the "aggregation" attack on claim 2 (strongest argument available on this record)

Claim 2 recites a bare set of parts: shaft/roller f in a sill receptacle with removable crank, side pieces a a, double wire rungs b, snap‑hooks d, and curbing rings e, "all substantially as described."
Argument: assuming each element is old (a roller/crank windlass is a notoriously old mechanical expedient; hooks, rings and eye‑plates are staple building hardware; straps and rungs are old), claim 2 is the classic aggregation: the elements are claimed as a mere juxtaposition with no recitation of a new cooperative relationship. Under Hailes v. Van Wormer and Pickering v. McCullough, that is unpatentable — the 1884 analogue of a § 103 rejection. The claim's own drafting helps the challenger: "all substantially as described" adds no structural limitation of its own.
Assessment: this is the argument most likely to succeed on the page's own material, and it does not depend on my unverified readings — but it does depend on each element being shown to be old, which brings us back to the gaps in § 4.

Theory D — the feature most resistant to § 103

The double wire rung — a single wire passed through both straps with its ends bent back and looped together, giving a doubled grip surface — plus the snap‑hook into a curbing ring sited away from the building to create the "gentle incline" and keep the descender clear of lower‑window flame. The specification expressly asserts these as advantages ("double rungs afford a firmer hold for the hand and feet, especially for children"; "the foot of the ladder being attached to the curbing at some distance from the building… persons descending from above will be clear of flames and smoke").
Applicant's counter: a § 103 challenger relying only on the page's listing cannot show these were known, and the patentee's asserted advantages, if supported by evidence, are objective indicia of non‑obviousness.
Challenger's rebuttal (needs art outside this page): anchoring the foot of a descent line away from the building to clear flame and smoke was itself an express, published teaching before 1883 — see US 194,989 (Chapman, Sept. 11, 1877): "If flame and smoke should issue from the lower portions of the building, the lower end of the rope may be carried away from the building, and the person, in this manner, may be conveyed to a distance from the building." That squarely undercuts Bartlett's stated advantage as an unexpected result. Chapman is not on the page's own list and must be independently added to the record.

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6. Reference materials retrieved incidentally (clearly OUTSIDE the page's prior-art list)

These surfaced during searching and are offered only as leads. None is on the page's "Similar Documents" list, so none is part of the designated prior art for this task; each would need its own verification and formal addition:

• US 194,989 — Chapman, "Improvement in Fire-Escapes," Sept. 11, 1877 — hinged frame + rope/seat; expressly teaches carrying the lower rope end away from the building to avoid flame/smoke. Highly relevant to Bartlett's asserted advantage.
• US 194,192 — Tixier, Aug. 14, 1877 — grooved/perforated cylinder with frame and a "single or double rope." Relevant to sill anchoring; also the source of the 194,082 confusion flagged above.
• US 194,443 — Knowlton, Aug. 21, 1877 — drum‑and‑rope friction block; note it uses a snap‑hook e hooking into a ring d ("one end of such strap has secured to it a snap-hook, e, which hooks into the ring d"). This is the closest disclosure I encountered to Bartlett's snap‑hook‑and‑ring limitation, but it is a body‑suspension hook‑and‑ring, not a curbing anchor.
• US 205,511 — Steifler — windlass/turn‑shafts with hand‑cranks and ratchet‑and‑pawl for raising and lowering ladders, incl. mounting on and off a carriage. Directly relevant to the "removable crank" limitation.
• US 290,254 — McCandliss, Dec. 18, 1883 (post‑dates Bartlett's filing) — rope end has hook M "hooked onto the window‑sill."
• US 277,433 — Todd & McKee, May 8, 1883 — rope "having at both extremities hooks… for attaching it to a window or other like portion of a building."
• US 286,306 — Johnson, Oct. 9, 1883 (post‑dates filing) — reel in a case with centrifugal friction governor; relevant to the roller‑and‑receptacle concept.
• US 273,807 — Braunfeld, Mar 13, 1883 — box/casing with pulleys, removable ring/loop attachment.

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7. Summary conclusion

1. Claim 2 is the claim most exposed. It is drafted as a bare combination of individually old mechanical elements (roller, crank, straps, rungs, hooks, rings) with no recitation of a novel cooperative relationship. On the 1884 aggregation doctrine (Hailes v. Van Wormer; Pickering v. McCullough) — the era analogue of § 103 — it presents a genuine invalidity risk provided each element can be shown old.
2. Claim 1 turns on two limitations I could not match to anything on the page's prior-art list: the double wire rung and the snap‑hook/curbing‑ring anchor. On the record supplied by this page, claim 1 is not clearly obvious. It becomes clearly obvious only once outside art is added (e.g., Steifler for the crank windlass; Knowlton for the snap‑hook‑and‑ring; Chapman for the "clear of flame and smoke" advantage).
3. The intuitive "prior art" of this page is largely the wrong art. Most listed documents are rope‑friction descenders, a different sub‑genre. The page's listing gives good evidence of field and motivation (same problem, same CPC class, sill‑anchoring taught by Holthausen, portability taught by Phillips) but poor evidence of the specific structural limitations.
4. Do not use the "Cited By" entry US 5,064,021 as prior art — it is 107 years too late.
5. Do not carry my unverified element mappings into any formal paper. Eleven of the thirteen pre‑filing references remain unread.

Overall confidence: HIGH on the date screening, the § 103 anachronism flag, the forward‑citation flag, and the two verified references (US 181,577; US 202,460 objective statement). LOW on any specific element‑to‑reference mapping drawn from the unread references, and LOW on the probable US 193,841 ≈ Hoyt identification.