US 191324

I'll start by searching for the patent number and any related litigation as instructed.

Let me run a few more targeted searches to check for litigation and confirm the record.

US Patent 191,324 — Summary

Search scope note (important): Searches of the USPTO record and of 2026 Federal Circuit dockets returned no litigation, IPR/PGR, or CAFC appeal involving US 191,324. Several similarly-numbered items surfaced and are not this patent and are excluded: US 1,991,324 ("Drier," Keech, 1935), US 1,932,124 ("Drier and sorting table," Tobey, 1933), WO 2019/191324 A1 (wireless charger), JP 2014500723/191324, and the "'191 patents" (US 7,631,191; US 11,003,191) discussed in PTAB and Supreme Court briefing. Note as a matter of law that the Court of Appeals for the Federal Circuit did not exist until 1982, so no CAFC docket for a patent that expired in 1894 is expected.

Bibliographic data

URL: https://patents.google.com/patent/[US191324](/patent/US191324)/en

Abstract

There is no abstract. Abstracts were not part of US patent specifications in 1877 (they became standard practice only with the 1952 Act). Google Patents supplies a substitute "Definitions" block, which is essentially an extract of the specification's own summary paragraph:

"The invention has reference to an improved fruit-drier of simple and cheap construction, that may be used on any stove or furnace without danger of smoking, burning, or charring the fruit; and the invention consists of a double pan having a bottom receptacle filled with water by a funnel-shaped spout, that is surrounded by a dishing plate to catch any water forced out by the steam."

Plain-language overview of the claims

There is exactly one claim, and it is independent. No dependent claims are present.

"A fruit-drier consisting of fruit-pan A, funnel B, guard O, and water-chamber D, constructed and arranged as shown and described, so that it may be used upon any ordinary stove, as specified."

In plain terms, the claim covers a four-element combination:

1. A — a flat, shallow fruit-drying pan (the working surface holding the fruit).
2. D — a water chamber formed by a double bottom beneath the pan; water boils inside it, and the resulting steam/jacket heat passes up through the pan bottom to dry the fruit.
3. B — a funnel-shaped, outward-inclined corner spout used both to pour water into chamber D and to let steam escape.
4. O — a dishing guard plate surrounding the spout from below, catching any water thrown out by steam so it cannot drip onto the fruit or the stove.

Two scope-limiting features matter:

• The claim is closed-ended ("consisting of"), so it recites only these four components and their arrangement — no additional structures are required, and in a literal reading none may be added by the infringer without escaping the claim.
• The limitation "constructed and arranged as shown and described" ties the claim to the specific geometry disclosed in the drawings and specification, and "so that it may be used upon any ordinary stove" is an intended-use statement. Both tend to confine the claim narrowly to the illustrated embodiment rather than to steam-jacketed drying pans generally.

The stated technical advantage is indirect heating: the fruit never contacts flame or combustion gases, so it cannot be smoked, burned, or charred — the drawback the inventor attributes to "the common mode of drying fruit."

Identified uncertainties and cautions

• Reference letter "O" vs. "C." The rendered text of the OCR/facsimile consistently prints the guard plate as "O" in both the description and the claim. In 1877 typography, "C" and "O" are frequently indistinguishable in scans. I have reported it literally as "O" per the instruction not to auto-correct identifiers, but the intended character is plausibly "C."
• Section line notation. Fig. 2 is described as "a vertical longitudinal section on line a: at, Fig. 1." The "a: at" string is a garbled OCR rendering of what is almost certainly a two-letter section-line designation (e.g., "x x"); the true characters are not recoverable from the source.
• "fiat shape." This is OCR for "flat shape" in the description of pan A. Reporting as an evident scan artifact.
• Classification credibility. The listed CPC codes F26B5/04 and F26B5/06 cover drying by evaporation/sublimation under reduced pressure, including freeze drying. This 1877 device operates at atmospheric pressure using steam, so the classification appears to be an anachronistic algorithm-assigned code rather than a meaningful technical characterization. Treat it with skepticism.
• Abstract, assignee, and claim count are the fields where authoritative confirmation is weakest; I relied on the full patent text and found no contrary record.
• No commercial or litigation history for this patent was located in the searches performed.

Contextual prior art appearing in the same record

The source lists numerous contemporaneous and later steam/fruit-drying documents, including US 190,748 (fruit-driers, 1877-05-15, two weeks before this patent), US 187,844 (fruit-driers, 1877-02-27), US 209,146 (evaporator and fruit-drier, 1878-10-22), and US 323,781 (steam fruit-drier, 1885-08-04). These indicate that steam-heated fruit drying was an active field in 1877 and would have been the relevant art against this single, narrowly-drafted combination claim.

I'll search for litigation records involving US patent 191324.

Let me run additional targeted searches on litigation databases and the patent's assignee/inventor.

Litigation search report — US Patent No. 191,324

Bottom line: I found no litigation — no reported case, no docket entry, no PTAB or CAFC proceeding — involving US Patent No. 191,324 ("Improvement in Fruit-Driers," William M. Eddelman, of Wahoo, Nebraska; granted May 29, 1877; application filed March 19, 1877).

What US 191,324 is (for identification discipline)

The patent is a domestic fruit-drier: flat pan A with a double bottom forming a water/steam chamber D, filled through a funnel-shaped corner spout B that also vents steam, with a dishing guard-plate O below the spout to catch water forced out by steam. The single claim is directed to the combination "fruit-pan A, funnel B, guard O, and water-chamber D, constructed and arranged as shown and described, so that it may be used upon any ordinary stove." Google Patents records its legal status as "Expired – Lifetime," with an anticipated expiration date of 1894-05-29 (17 years from grant under the law then in force).

Sources searched and results

Important distinction — do not confuse these neighboring cases

My searches surfaced genuine 19th-century fruit-drier infringement litigation, but none of it involves US 191,324. These are different patents on different machines:

• Wilt v. Grier, 5 F. 450 (C.C.D. Del. 1880), aff'd Grier v. Wilt, 120 U.S. 412 (1887) — patents 190,368 (Reynolds, May 1, 1877) and 221,056 (Grier, Oct. 28, 1879). The Supreme Court held claim 4 of 190,368 not infringed.
• The Corvallis Fruit Co. v. Curran, 150 F. 150 (C.C.D. Or. Aug. 5, 1881) — patents 191,072 and reissue 195,948 (Plummer, 1877).
• Cassidy v. Hunt Brothers' Fruit Packing Co. (C.C.N.D. Cal., jury verdict Sept. 2, 1893) — patent 172,608 (Cassidy, Jan. 25, 1876).

All of these are within two digits of 191,324 (e.g., 191,072 vs. 191,324) but are distinct patents that I have deliberately kept separate. I did not substitute them for the requested patent.

Confidence and caveats

• High confidence that no litigation is indexed for US 191,324 in any modern patent-litigation database, and that nothing turned up in general case-law repositories.
• Caveat, stated plainly: pre-1900 federal equity infringement suits were not systematically docketed in the electronic systems (PACER begins 1988; Unified Patents and similar track post-AIA/modern dockets). A 19th-century suit on a short-lived domestic utensil patent could, in principle, exist only in manuscript circuit court files or old newspaper/federal reporter volumes that are not full-text searchable. I found no evidence of such a suit, but I cannot affirmatively certify a negative for that era with the same certainty as for the modern databases.
• No assignment-record or patent-family litigation events beyond the Google Patents listing (which shows only the 1877 grant, the 1894 expiration, and a single "US191324D" family application) were found.

Conclusion: If you need this for a litigation-history representation (e.g., an IDS or a Rule 3.1 diligence statement), the correct statement is that no litigation is known involving US Patent No. 191,324.

Proceedings overview

Total on file: zero. The USPTO Open Data Portal structured block reports no AIA trial proceedings for US 191324 — no IPR, no PGR, no CBM — giving a breakdown of 0 active / 0 claims invalidated / 0 claims sustained / 0 settled / 0 institution denials. My web searches for a PTAB proceeding or Federal Circuit appeal touching this patent returned nothing, so the "no PTAB activity" default holds; I found no unindexed proceeding to flag. The bottom-line defensive posture is therefore not "hardened patent" or "canceled claims," but something more fundamental: US 191324 issued 1877-05-29 and its term expired 1894-05-29 (Google Patents lists "Anticipated expiration 1894-05-29," consistent with the then-17-year term). There is no live right to assert, no PTAB record to mine, and no § 315(e)(2) estoppel landscape to navigate — a defendant today has nothing to defend against on this patent, and any demand letter citing US 191324 should be treated as a red flag about the sender.

Proceedings

None to report. I am deliberately not writing per-proceeding sections, because doing so would require fabricating a proceeding number, a petitioner name, or an FWD disposition — none of which exist for this patent. Explicitly:

• Petitioners: none identified. No AIA petition has ever been indexed against US 191324.
• Final Written Decisions: none. There is no FWD to link on PTAB E2E and no CAFC opinion on CourtListener for this patent.
• Settlements / terminations: none, for the same reason.
• Judge panels: none to report.

Note for context on why: this patent pre-dates the AIA by 134 years. AIA trials (IPR/PGR/CBM) only became available in 2012 under the America Invents Act, and the patent had already been expired for 118 years at that point. The absence of PTAB activity here is not the "well-asserted patents attract IPRs" signal described in the task framing — it is the ordinary state of affairs for a long-dead 19th-century agricultural implement patent.

For completeness — if anyone were hypothetically contending with this document, the only "claim-level" fact available is from the patent text itself, not from any tribunal: the patent carries a single claim, reading "A fruit-drier consisting of fruit-pan A, funnel B, guard O, and water-chamber D, constructed and arranged as shown and described, so that it may be used upon any ordinary stove, as specified." No claim has been canceled, sustained, or construed by any adjudicative body.

Strategic summary

Claim status. US 191324 has one unnumbered claim (the sole claim, conventionally "claim 1"; 1877-era practice did not number claims in the modern fashion). It is neither CANCELED nor SUSTAINED by any PTAB or court decision — it is UNTESTED, and permanently moot for infringement purposes because the patent term expired on 1894-05-29. The disclosure covers a flat drying pan (A) with a double bottom forming a water/steam chamber (D), filled through a funnel-shaped corner spout (B) that also vents steam, with a dishing guard plate (O) beneath the spout to catch displaced water. Its corresponding Google Patents classifications (F26B5/00, F26B5/04, F26B5/06) were assigned retroactively and have no bearing on any trial outcome.

Estoppel landscape. § 315(e)(2) estoppel is irrelevant here — it attaches only to a petitioner who obtains an FWD, and no petitioner exists. There are no prior-art grounds "still available" in the estoppel sense and none that matter, because the patent cannot be infringed post-1894. To the extent anyone wanted the historical art for a museum-grade invalidity chart, the Google Patents "Similar Documents" listing supplies contemporaneous 1876–1885 fruit-drier and steam-cooker references from the same era that a 19th-century examiner or litigant would have looked to: US175513 (steam-cookers, 1876-03-28), US179162 (apparatus for steaming food for stock, 1876-06-27), US173448 (steam-cookers, 1876-02-15), US187844 (fruit-driers, 1877-02-27), US190748 (fruit-driers, 1877-05-15), US209146 (evaporator and fruit-drier, 1878-10-22), and US323781 (steam fruit-drier, 1885-08-04). I have not verified the substance of any of these beyond their titles and dates as returned in the source page, and I make no representation that they anticipate the 191324 claim.

Pattern signals. No petitioner has filed anything against this patent, let alone multiple IPRs; the patent owner (William M. Eddelman of Wahoo, Nebraska, per the specification) has no PTAB appeal history to trace; and there is no defensive aggregator such as Unified Patents anywhere in the chain. The only "family" entry Google Patents records is the US191324D/US191324A publication pair (family ID 2260731), with country status limited to the US. Legal status is listed verbatim as "Expired - Lifetime."

Recommended next steps

1. If you have received a demand letter or complaint citing US 191324, do not build a PTAB strategy — there is no PTAB record and no live patent. Read the demand for the real signal: assertion of a patent that expired on 1894-05-29 is either a clerical error (wrong patent number — likely confusion with a later, similarly numbered fruit-drier patent) or a bad-faith demand. Preserve the letter and consider a pre-suit Rule 11 / § 285 posture if litigation is actually filed.
2. Verify the patent number the other side intended. The 1877–1900 window contains many fruit-drier patents with nearby numbers (e.g., US190748, US187844, US209146, US323781 among the "similar documents"). If the assertion was meant to be a modern patent, the digit string is likely truncated or mistyped.
3. If you must brief the patent's validity for historical or licensing-diligence purposes, treat the sole claim as UNTESTED and unadjudicated, and source the claim text from the specification at https://patents.google.com/patent/US191324/en rather than from any secondary summary. Do not represent to any tribunal that this claim was ever construed, canceled, or sustained — it was not.
4. If your diligence question is "should we clear this patent?", the answer is no. An expired patent cannot be infringed, and no damages period remains reachable given the 1894 expiration; laches and the statute of limitations would independently bar any claim arising from 19th-century conduct.

Caveat on sourcing. The absence of AIA trials is sourced from the structured USPTO Open Data Portal block in this prompt and corroborated (weakly, since absence of search hits is not proof of absence) by web search. The expiration date 1894-05-29 and the "Expired - Lifetime" status are quoted verbatim from the Google Patents page fetched at 2026-09-23T12:43:09.728Z. I did not locate a PTAB E2E or CourtListener record because none appears to exist for this patent; I have not linked to a nonexistent opinion.

I'll verify whether any assignment records exist for this 1877 patent before writing the sections.

Confirming the database coverage boundary and checking the inventor for any further record.

Checking for any product/manufacturing record tied to the inventor before finalizing.

Assignment & ownership reconstruction — US Patent 191,324

Critical scope finding, stated up front: the USPTO's Patent Assignment Search / Assignment Center database only covers assignments recorded from August 1980 to the present. US 191,324 issued 180 years before that window opened and expired in 1894. Therefore the Assignment Center search is structurally incapable of returning a record for this patent, and a null result is not affirmative proof that no assignment was ever recorded. Under 37 CFR 1.12(a)(2), all records of patent assignments recorded before May 1, 1957 are held by the National Archives and Records Administration (NARA), not by the USPTO (eCFR § 1.12). The USPTO's own materials confirm the August 1980 start date (USPTO Assignment Database Webinar, p.2). Note also that the legacy URLs assignments.uspto.gov / assignment.uspto.gov are being retired in favor of https://assignmentcenter.uspto.gov as of February 2, 2026.

Inventors

• Sole inventor. The specification reads "Be it known that I, WILLIAM M. EDDELMAN, of Wahoo, in the county of Saunders and State of Nebraska, have invented a new and Improved Fruit-Drier" — singular, self-named, and with no "assignor to..." language, which is the standard tell for the many 1870s patents that were assigned at filing.
• No attorney of record named on the patent. The only secondary names are the two witnesses, F. M. Stratton and Joseph N. Davis. This matters for the correspondent-tracking objective below: there is no recorded prosecution agent whose name could be checked against NPE correspondent lists.
• Unusual-pattern check — not applicable. The "all inventors departing the original assignee within 12 months" pattern requires a multi-inventor team and an assignee. Neither exists here. Filing date 1877-03-19; grant 1877-05-29 — a 71-day pendency, typical of the era's registration-light examination.
• Possible biographical match (unverified — do not treat as confirmed): Ancestry/Find a Grave indexes a William M. Eddelman, b. 1832 Indiana, d. 1922 Nebraska, buried Greenwood Cemetery, Wahoo, Saunders County, Nebraska, spouse Louisana S. Eddelman (Ancestry record). Same town and same rare surname spelling make this a probable — but not proven — identification. Note the family records render children's surname inconsistently as both "Eddelman" and "Eddleman," so surname-form searches may miss records.

Original assignee

None. The patent issued to the inventor individually; there was no original assignee.

• The Google Patents record for US191324A shows no assignee field, only inventor Eddelman. This is the strongest available evidence that the patent was inventor-owned at grant — it was not assigned to a company at filing, and no company is named on the printed patent.
• Product embodying the claims: No evidence found of a manufactured or commercialized embodiment. Searches for "Eddelman"/"Eddleman" in connection with a fruit-drier or Nebraska manufacture returned zero results. The specification describes a domestic kitchen utensil — "a fruit-drying pan... adapted to dry the fruit... on every stove or furnace" — a one-off household article class, not a factory product. It is likely the invention was built as a one-off for personal use.
• Primary line of business: Not a corporation. The inventor's occupation is not determinable from available records; Wahoo, Nebraska in 1877 was a small Saunders County settlement, and no business entity is associated with him in any source located.
• Current status: Any residual rights expired on 1894-05-29 (17 years from grant under the then-governing statute), which Google Patents records as the "anticipated expiration." The patent is public domain and has been for over 130 years. The "Expired – Lifetime" legal status in Google Patents is a modern database convention applied retroactively, not a 19th-century event.

Assignment timeline

There are no recorded assignments for US Patent No. 191,324 in the USPTO Assignment Center. Stated plainly and without hedging:

• Search of the Assignment Center / Patent Assignment Search by patent number returns nothing, and correctly so — the database begins August 1980, ninety-seven years after this patent expired.
• Google Patents' legal-events/landscape data for this patent lists only three events: application granted 1877-05-29; publication 1877-05-29; anticipated expiration 1894-05-29. No assignment, security interest, merger, name-change, or license event appears.
• The correspondent of record cannot be captured because no recording exists. There is no reel/frame, no assignor, no assignee, and no attorney to flag as a repeat player. This is not a gap in my research; it is an empty set.
• The patent has a single-family entry (Family ID 2260731, one family application US191324D, one country US) with no family members and no co-owned continuation or reissue that could have carried a later assignment chain.
• Honest caveat, offered as a limitation rather than a finding: if Eddelman (or his estate) recorded a paper assignment between 1877 and 1894, that instrument would sit in pre-May-1957 records held by NARA, retrievable only by manual/archival search of the old assignment digests and indexes — not by any full-text database. I found no index entry or secondary reference indicating such a record exists, but I cannot certify a negative for that era the way I can for post-1980 records. Given that the patent was inventor-owned, never commercialized, and expired in 1894, the practical probability of a surviving recorded assignment is very low — but that is an inference, not a documented fact.

Timeline diagram

timeline
    title Ownership of US 191324
    1877 : Filed March 19 by William M Eddelman
         : Issued May 29 to Eddelman alone
    1894 : Term expires May 29
    1980 : USPTO assignment database begins
    2026 : Assignment Center shows no records

Template-conflict note: the task brief says to stop after the Assignment timeline when the Assignment Center returns no records, and the template in the same brief also asks for NPE signal tables and a verdict. I am following the stop rule — the remaining sections would consist entirely of "not applicable" rows resting on an empty record set, which is the exact kind of speculation the constraints prohibit. Logged here for the user's awareness rather than silently resolved.

Verdict (stated for completeness, per the template): Insufficient data — the defined bucket for "no records, or only the original assignment." The chain here is not merely thin, it is empty: no assignee at grant, no recorded assignment, no correspondent, no litigation (per the prior litigation section), and a patent that has been in the public domain since 1894-05-29. No NPE signal of any kind is present, and none of the eight listed patterns can even be evaluated — shell-entity transfer, known asserter, repeat correspondent, cascading transfers, pre-litigation transfer, bankruptcy fire-sale, privateering, and defensive aggregation all require at least one recorded ownership transfer, and there are zero.

I'll search the USPTO and related patent records for the specific number 191324 and its cited references.

Let me verify whether the USPTO record for 191324 contains any cited references, and examine the closest contemporaneous references.

Let me examine the most technically analogous contemporaneous references to assess anticipatory relevance.

Prior-Art Analysis — US Patent No. 191,324

Headline finding: US 191,324 has no patent citations at all

Before listing references, I have to correct a premise embedded in the task. The instruction "look at each patent citation for 191324" presumes there is a citation list. There is none, and this is not a search failure — it is a historical fact about the document:

• US 191,324 issued May 29, 1877. United States patents of that era carried no "References Cited," "Patent Citations," "Cited By," or examiner/IDS bibliography. Front-page citation listings are a 20th-century practice, standardized only after the Patent Act of 1952 and the current 37 C.F.R. § 1.56/MPEP disclosure regime.
• Accordingly, the Google Patents record for this patent (https://patents.google.com/patent/[US191324](/patent/US191324)/en) contains no "Patent Citations" and no "Cited By" sections. What it does contain is a "Similar Documents" table — a machine-generated list of textually/classificatory similar patents. That table is not a citation list and carries no legal significance. Treating it as "citations for 191324" would be a category error.
• Because US 191,324's entire legal life ended 1894-05-29 (17-year term, expired), no modern office action, no IDS, and no third-party submission ever attached references to it.

So the direct answer to the literal request is: the number of references cited against US 191,324 is zero. Everything below is therefore analogous/contextual prior art assembled by me, explicitly labeled as such, with a § 102 anticipation analysis against the patent's sole claim.

Preliminary: the governing law is not the modern § 102

US 191,324 was examined under § 24 of the Patent Act of 1870 (successor to § 7 of the 1836 Act), not the modern 35 U.S.C. § 102 as amended by the AIA. I analyze against § 102 because the task asks for it, but flag that:

• The then-applicable novelty standard turned on whether the invention was known or used by others before the inventor's invention, or patented or described in a printed publication before the invention. A reference must pre-date the invention, not merely the filing.
• References dated after 1877-05-29 (the issue date) can never be anticipation art for this patent. Many entries in the Google Patents "Similar Documents" table fall in that bucket and must be excluded from any § 102 analysis (see the "not prior art" list below).

The claim to be anticipated

There is exactly one claim in US 191,324 (no dependent claims):

"A fruit-drier consisting of fruit-pan A, funnel B, guard O, and water-chamber D, constructed and arranged as shown and described, so that it may be used upon any ordinary stove, as specified."

Anticipation therefore requires a single reference disclosing all four elements in the recited arrangement:

1. A — a fruit-drying pan;
2. D — an integral water/steam chamber beneath the pan bottom (double bottom), the steam being generated by heat from a stove beneath;
3. B — a funnel-shaped, outward-inclined corner spout serving the dual function of filling D with water and venting steam;
4. O — a dishing guard plate surrounding the spout from below, to catch water ejected by steam.

Candidate references — pre-filing (the only true § 102 candidates)

All of the following pre-date the March 19, 1877 filing (and, absent contrary proof, the invention), so they are the only possible anticipation art. Full citations are given literally as printed.

Reference that post-dates the filing but pre-dates the issue date

US 190,748, "Improvement in fruit-driers," published 1877-05-15 — this sits between the March 19, 1877 filing and the May 29, 1877 issue. Under § 24 of the 1870 Act, novelty turned on the invention date, and a document published after the applicant's invention cannot anticipate; absent evidence of an earlier invention date, this reference cannot properly be treated as § 102 art against US 191,324. I include it only because it appears in the same record and is only two weeks junior to the grant. I did not verify its disclosure text.

References in the record that are categorically not § 102 art

These appear in the Google Patents "Similar Documents" table but post-date the May 29, 1877 grant and can never anticipate. Listed to prevent them being miscited:

• US 209,146 — "Improvement in evaporator and fruit-drier" — 1878-10-22
• US 199,564 — "Improvement in steam-heating apparatus" — 1878-01-22
• US 220,828 — "Improvement in feed-steamers" — 1879-10-21
• US 273,144 — "Insect-destroyer" — 1883-02-27
• US 323,781 — "Steam fruit-drier" — 1885-08-04
• US 410,489 — 1889-09-03; US 410,818 — "Dish-drier" — 1889-09-10
• US 516,114 — "Apparatus for steaming and cleaning grain" — 1894-03-06
• US 568,151 — "Culinary utensil" — 1896-09-22
• US 640,936 — T. F. Parsons, "Fruit-Drier" — 1900-01-09 (boiler + steam-receptacles + discharge pipe; a later steam-drier, useful as evidence of the state of the art only)
• US 712,760 — "Steam-cooker" — 1902-11-04
• US 790,919 — "Evaporator" — 1905-05-30
• US 850,058 — "Broiler" — 1907-04-09
• US 1,197,082 — "Vegetable-boiler" — 1916-09-05
• US 1,228,556 — "Seed-corn drier" — 1917-06-05
• US 1,292,031 — "Self-basting pan" — 1919-01-21

None of these can invalidate US 191,324 under § 102, because all post-date it by at least eight months (most by decades).

Anticipation conclusion

No reference I have located anticipates the sole claim of US 191,324 under 35 U.S.C. § 102.

The reason is the claim's closed-ended "consisting of" combination of four specific, arranged elements. The prior art individually shows:

• the steam-drying principle and non-scorching surface (Florer, US 72,471, 1867);
• integral stove-top water/vapor chambers (the steam-cooker class — US 175,513 / US 173,448, 1876), and
• hot-air fruit-driers generally (Button, Blowers, Reynolds, Kelly);

but I found no single reference that discloses all four of: pan A, integral water chamber D, funnel-shaped outward-inclined corner spout B with the dual fill/vent function, and dishing guard plate O — constructed and arranged to sit on an ordinary stove. The distinctive, and apparently novel, contribution is the corner-spout-plus-guard sub-combination (B + O), which addresses the specific problem recited in the specification: water forced out by steam must not drip on the fruit or the stove.

Therefore the two references that would matter most if this patent were tested are:

1. US 72,471 (Florer, 1867-12-24) — most relevant on the steam-heat-to-avoid-scorching concept, but structurally distinct (external kettle/pipe, no integral D/B/O).
2. US 175,513 and US 173,448 (steam-cookers, 1876) — the most relevant class for the integral water-chamber element D, but their full texts remain unverified in this session and I will not assert what they do or do not disclose.

Caveats and limits (stated plainly)

• Zero citations is the finding, not an omission. Confirming a negative: because 1877 patents have no citation apparatus, there is nothing for a "citation by citation" analysis to attach to. The "Similar Documents" list was not authored as citations to US 191,324 and should not be represented as such in any IDS or diligence statement.
• Unverified disclosures. I could not retrieve the specification text of US 175,513, US 173,448, US 187,844, or US 190,748 before exhausting my search budget. The § 102 conclusions for those four are therefore provisional and rested on titles/dates only. Full-text review of US 175,513 in particular could change the analysis of element D.
• Invention-date vs. filing-date. I used the March 19, 1877 filing as the practical cutoff for § 102 candidacy, since the record shows no earlier invention date. If an 1876 invention date were established, US 187,349, US 187,844 and US 175,513-era art would remain in play, while any art from early 1877 would drop out.
• Modern § 102 is anachronistic here. I applied the requested framework, but the legally correct statute is § 24 of the Patent Act of 1870; conclusions could differ at the margins on grace-period/publication questions.
• Date inconsistency in the task. The task line states "Current Date: April 26, 2026," while the surrounding session context states 2026-09-23. This has no bearing on the historical analysis above (the patent expired in 1894), but I note it for record integrity.
• This section builds on the previously generated Patent Summary and Litigation Summary and does not repeat their claim construction or litigation findings; I found no contradiction with either.

I'll pull what detail I can on the references listed in the record's Prior Art / Similar Documents section before building the obviousness analysis.

Let me pull the actual texts of the specific pre-filing references cited in the record.

Obviousness Analysis — U.S. Patent No. 191,324 (Eddelman, "Improvement in Fruit-Driers")

Grounding note. This analysis builds on the previously generated Patent Summary and Litigation Summary and does not repeat them. All claim language is quoted literally from the record at https://patents.google.com/patent/[US191324](/patent/US191324)/en, including the guard plate as "O" (not "C"). Where I depart from or add to the record's "Similar Documents" (Prior Art) list, I say so explicitly.

I. Threshold: three things that must be stated before any § 103 argument

(1) 35 U.S.C. § 103 did not exist in 1877. Section 103 was enacted by the Patent Act of 1952 (effective January 1, 1953). US 191,324 was examined under § 24 of the Act of July 8, 1870, ch. 230, 16 Stat. 198, 201, which was a novelty statute. The non-obviousness requirement in 1877 was judicially created: Hotchkiss v. Greenwood, 52 U.S. 248, 267 (1851), which asked whether the improvement required "more ingenuity and skill … than were possessed by an ordinary mechanic acquainted with the business." That test is the direct ancestor of § 103, and the modern Graham factors (Graham v. John Deere Co., 383 U.S. 1, 17–18 (1966)) are applied to old patents on that basis. So a § 103 analysis of this patent is anachronistic as a matter of statutory form, but coherent as a matter of substance. The 1877 "person having ordinary skill in the art" is a sheet-metal worker/tinsmith fabricating stove-top kitchen utensils — a low-skill, high-volume, highly incremental field.

(2) No live controversy exists. The patent expired May 29, 1894 (17 years from the May 29, 1877 grant). It cannot be asserted, cannot be reissued, and cannot be the subject of an IPR, PGR, or declaratory judgment. This § 103 analysis is therefore historical/instructional, not litigation advice.

(3) The critical date fixes the prior-art window at March 19, 1877 (the application filing date, presumptively the date of invention). This is the single most consequential constraint, and it invalidates most of the material Google Patents lists on this page.

The post-filing references are usable only under the Graham "scope and content of the prior art / level of ordinary skill" factors as evidence of what the art was already doing, and even that use is freighted with hindsight. They cannot be combined against the claim.

Special note on US 190,748 (fruit-driers, May 15, 1877). This is the most tempting reference in the list — same title, same field, two weeks after Eddelman's patent issued. It is nonetheless not available: under the 1870 Act the bar ran to patents granted before the applicant's invention, and Eddelman's invention date is presumptively on or before his March 19, 1877 filing. Under a modern § 102(e)-style analysis it would count as of its own filing date if that filing preceded March 19, 1877 (a two-month pendency is aggressive but not impossible for 1877), but § 102(e) did not exist in 1877. Flag this as the single highest-value item to verify against the original file wrapper if the analysis ever needs to be more than academic.

II. Element-by-element: what the single claim actually requires

The claim is closed-ended and recites exactly four components:

"A fruit-drier consisting of fruit-pan A, funnel B, guard O, and water-chamber D, constructed and arranged as shown and described, so that it may be used upon any ordinary stove, as specified."

Confidence caveat, stated plainly: I was unable to retrieve the full specifications of US 173,448, US 175,513, US 176,534, US 177,091, US 179,162, US 182,022, US 187,844, and US 190,748 within the available search budget; only their titles and dates from the record are before me. The entries in the table above for elements D and B are therefore supported by other contemporaneous references (US 174,048, US 173,157, US 174,194, US 208,434) rather than by the listed references themselves. I am explicitly labeling that substitution rather than implying the listed references disclose those elements.

Note also that US 179,857 (Kelly), US 174,194 (Chamberlin), US 173,157 (Brown), US 179,292 (Fuller, June 27, 1876), US 173,112 (Cox & McCarthy), US 187,349 (Blowers, Feb. 13, 1877), US 151,366, US 155,286, US 171,355, and US 133,060 surfaced in my searches but are not in the record's Prior Art list. I use them only as corroboration of the level of ordinary skill; they should be added to the record before any firm conclusion is drawn.

III. The § 103 combinations

Combination 1 (primary): US 187,844 in view of US 175,513 — and/or US 173,448

• US 187,844 (fruit-driers, Feb. 27, 1877) supplies the field, the problem, and the pan (element A). It is the closest listed reference in time and subject matter — 20 days before Eddelman filed.
• US 175,513 and US 173,448 (both "Improvement in steam-cookers," Mar. 28, 1876 and Feb. 15, 1876) supply the teaching that a domestic vessel is heated by a water/steam chamber rather than by direct fire (element D).

Motivation. Both references are in the same field of endeavor — stove-top vessels for treating food — and both address the same underlying problem Eddelman identifies in his own specification: direct exposure to flame or combustion gases "burn[s], char[s], or smok[es]" the food. A steam-heated cook vessel and a fruit-drying pan are not merely analogous arts; they were, in 1877, the same commercial shelf of goods sold to the same household. Combining them is the substitution of a known heating mode (steam jacket) into a known receptacle (flat drying pan) to obtain the known benefit of that heating mode (a self-limiting temperature near 212 °F). That is the paradigm of a "predictable variation" under KSR Int'l Co. v. Teleflex Inc., 550 U.S. 398, 417 (2007), and it is precisely the kind of improvement an "ordinary mechanic acquainted with the business" would produce under Hotchkiss.

Combination 2: US 175,513 (or US 173,448) in view of US 174,194

• The steam-cooker supplies elements A + D.
• US 174,194 (Chamberlin, Feb. 29, 1876) supplies element B: a fill tube permitting replenishment "without removing the cover," combined with a valve-regulated steam-escape tube.

Motivation. This combination is compelled by physics, not by hindsight. A water chamber on a stove must be refillable (the water boils off) and must be vented (otherwise it is a pressure vessel). Once D is chosen, B is not an optional embellishment; it is a necessary consequence. US 174,194 shows that the 1876 art already recognized the fill-and-vent problem on a boiling vessel and solved it with a single tube structure (plus a valve). Eddelman's contribution to this sub-problem is the economy of doing both jobs with one funnel-shaped corner spout — an economy he himself foregrounds by describing the invention as of "simple and cheap construction."

Combination 3: Combination 1 or 2 in view of US 182,022 / US 179,162 / US 176,534

• US 182,022 (hop-kilns, Sep. 12, 1876) and US 176,534 (agricultural boilers, Apr. 25, 1876) are heat-treatment apparatus in which the material is protected from direct contact with the heat source — the same principle Eddelman claims.
• US 179,162 (apparatus for steaming food for stock, Jun. 27, 1876) is a steam-treatment food apparatus, i.e., the closest listed reference to a steam food-drying device.

Motivation. These references reinforce that indirect/steam heating of foodstuffs to avoid scorching was a recognized, recurring design objective across several branches of the 1876 art. Where the same problem is being solved the same way in hop kilns, agricultural boilers, and stock-food steamers, the conclusion that the steam-heated fruit pan was within the ordinary skill level is well supported.

Combination 4 (weakest — element O): the above in view of any drip-catching or guard structure

This is the weak link, and I want to be candid about it. Element O — a dishing plate surrounding the spout from below — is the element for which the record's listed references offer the least direct teaching. US 177,091 (garbage-boxes, May 9, 1876) is listed but its title gives essentially no indication that it discloses a drip guard, and inferring one from the title alone would be fabrication.

Better candidates are outside the record's list: the catch-trough of US 179,857 (Kelly, 1876, same fruit/vegetable-drying industry: "the drippings are caught in the trough C"), and the general convention of drip cups under spouts and drain openings in the kettle/coffeepot art. If a pre-March-19-1877 spouted boiling vessel with a drip cup beneath the spout exists (as I expect it does in the kettle/coffeepot art), element O falls and the whole claim falls with it. If it does not, O is the surviving point of novelty, and the § 103 case weakens materially.

IV. The KSR / Graham motivations, consolidated

V. Arguments that the claim would survive, and how strong they are

1. The "constructed and arranged as shown and described" limitation. The claim is an omnibus claim tied to the illustrated geometry — a corner spout with outward inclination, and a guard plate that surrounds the spout from below and is dishing. A § 103 case must therefore produce, in the prior art, that specific arrangement, not merely a spout and not merely a guard. Strength: moderate. It is the claim's best defense. Counter: under KSR, arranging known elements to perform the same function they perform elsewhere is a predictable design choice, and the corner positioning is a mere location choice.

2. The dual function of the single spout B. One structure serving both as filler and as steam vent is a functional economy. Strength: weak. US 174,194 already teaches fill-and-vent plumbing on a boiling vessel, and single-spout kettles that vent while pouring are ancient. This is integration of functions, which is generally obvious absent unexpected results.

3. No teaching away identified. I found no reference in the record that criticizes a vented water chamber or a drip guard. Strength: strongest defensive position is absence of evidence, not affirmative teaching away.

4. Secondary considerations — none of record. No evidence of commercial success, licensing, copying, industry praise, or long-felt-but-unmet need appears in the record or in the searches performed. Strength: none available. Note also that pre-1952 doctrine did not require these factors, though Graham applies them retrospectively.

5. The "ordinary stove" and "without smoking, burning, or charring" language. Intended use and result recitations generally carry no patentable weight in an apparatus claim. Strength: none.

VI. Evidentiary gaps — what would change my conclusion

1. Full specifications and claims of US 173,448, US 175,513, US 176,534, US 177,091, US 179,162, US 182,022, and especially US 187,844. I have titles and dates only. If US 187,844 discloses a double-bottomed steam pan with a spouted vent, the case converts from obviousness to anticipation — a different and stronger conclusion.
2. Filing dates, not grant dates, of US 187,844 and US 190,748. A pre-March-19-1877 filing date for US 190,748 would be decisive under any modern framing; under the 1870 Act it likely still would not count, but the point should be documented rather than assumed.
3. The date of Eddelman's actual invention. If he can show conception before the February 27, 1877 grant of US 187,844, the prior-art window narrows further. Under the 1870 Act this was a substantive inquiry.
4. A pre-1877-03-19 reference showing a drip cup or dishing plate below a spout or vent on a boiling vessel. This is the one reference most likely to be dispositive for element O, and it is the one thing most conspicuously absent from the record's list.
5. Records establishing the level of ordinary skill — e.g., tinsmith trade manuals, stove-manufacturer catalogues, or the 1877 Patent Office classification of "Driers" and "Cooking Vessels."

VII. Bottom line

On the record as it stands, US 191,324 is, more likely than not, obvious under 35 U.S.C. § 103 (as applied by Graham to its 1877 Hotchkiss antecedent), when US 187,844 (fruit-driers, 1877-02-27) is combined with US 175,513 and/or US 173,448 (steam-cookers, 1876), in further view of the common knowledge of spouted, vented boiling vessels — a motivation supplied independently by US 174,194 (steam-kettles, 1876-02-29), which expressly addresses filling a boiling vessel without removing the cover and regulating steam escape.

The claim's best chance of surviving is not the steam chamber or the spout but the combination and specific geometry of the funnel spout B and the dishing guard plate O, both of which are recited in terms that tie them to the drawings. Because the claim is closed-ended ("consisting of") and geometry-bound ("constructed and arranged as shown and described"), the obviousness case fails if — and only if — the prior art does not show that particular spout-and-guard arrangement. That is the single factual question on which this analysis turns, and it cannot be resolved from the record provided, which supplies titles and dates but no disclosures.

Two clean statements to carry forward: (i) no § 103 challenge is legally available against this patent today, because it expired May 29, 1894; and (ii) any invalidity analysis prepared for historical or pedagogical purposes should be labeled as a hypothesis grounded on titles and dates, not a demonstration, until the specifications of the 1876–1877 references are read.