US 135541

I'll search for this specific patent number in USPTO and CAFC contexts.

Let me run additional targeted searches to confirm the patent's identity and check for any CAFC litigation.

Search results and summary — US patent 135541

Search scope and results

• USPTO / Google Patents record for US135541: found — US135541A, "Improvement in compression basin-faucets" (https://patents.google.com/patent/[US135541](/patent/US135541)/en).
• CAFC 2026 dockets: no results. Nothing ties 135541 to any Federal Circuit appeal. I also note the intrinsic reason: the record shows this patent expired 1890‑02‑04, and the Federal Circuit was created in 1982 — so no CAFC litigation over this patent is possible. I found no litigation of any kind in the returned results.
• Caution on the number itself (interpreted literally, not auto-corrected): the identifier 135541 matches an 1873 US patent (6-digit grant number). Unrelated documents also carry the substring "135541" — e.g., Japanese publication HEI 1‑135541 (Cu‑zeolite catalyst) and WIPO publication WO 2010/135541 (PCT/US2010/035586). These are different documents and are not the patent sought. No modern US patent numbered 135,541 exists, and no separate document US135541D/US135541DA should be read as a grant — those are Google Patents' internal record IDs for the same case.

Bibliographic summary (US135541A)

Plain-language overview of the claims

This 1873 patent predates the modern independent/dependent claim format, so all six claims are stand-alone combination claims; none depends from or incorporates another claim, and none is expressly labeled "independent." Treated functionally, all six are independent. The invention is a "swing-compression" basin faucet: a screw-down compression stem that also swings, with two valves so the water is shut off in either swung-back position and flows only when the nozzle points forward.

1. Claim 1 — cap + screw-socket on the stem. The combination of the water-chamber cap (B), having a screw-socket (D), with the stem (C). Plainly: mount the threaded stem through a socket formed in the cap, rather than a conventional packing-nut arrangement.
2. Claim 2 — cap/screw-socket/stuffing-box + stem + packing ring. The combination of cap (B) having screw-socket (D) and stuffing-box (h), with the screw-stem (C) and packing-ring (i). Plainly: seal the rotating/threaded stem where it passes through the socket so water cannot leak along the screw threads.
3. Claim 3 — upper valve seat on the socket end + upper valve. The upper valve-seat (b′) formed on the lower end of the screw-socket (D), in combination with the upper valve (E′). Plainly: the socket's own lower end doubles as the seat for a second (upper) valve, giving shut-off when the nozzle is swung back to the left.
4. Claim 4 — annular chamber in socket end + cross-opening in stem. The annular chamber (d) at the lower end of the screw-socket, in combination with the cross-opening (e) of the valve-stem. Plainly: water entering the annular chamber passes sideways through the stem's cross-opening into the stem's central passage (f).
5. Claim 5 — screw-cap + nozzle ball with annular space + stem with side-opening (OCR degraded). As printed: "The combination of the screw-cap H, the ball G of the nozzle, having an annular space, u, and the screw-stem C, having a side-opening, o." The description identifies the ball's annular space as n and the stem's side-opening as o, and states the ball is secured to the tapered stem end by screw-cap (H). Plainly: a swivel joint in which the ball's internal annular space (n) keeps the stem's side-opening (o) in continuous communication with the nozzle passage in any swing position. Uncertainty: the claim's "u" is almost certainly an OCR error for "n"; I cannot verify the original printed character from this source.
6. Claim 6 — adjustment openings + pin. The combination of the vertical openings (j) and pin (m) with the upper end of the screw-stem and the ball (G) of the nozzle. Plainly: a positive, indexable adjustment that sets how far the nozzle swings back so that it is correctly positioned exactly when a valve seats.

Important caveats

• No abstract exists for this patent; any "abstract" text circulating for it is an invention of a modern database, not the original document.
• No filing/application date or application number appears in the authoritative record; only the 1873‑02‑04 grant (and the same date used as the prior-art key date).
• Claim 5's text is partly corrupted in the source; my reading rests on reconciling it with the specification's n/o/H elements.
• No CAFC or other litigation records were found for 135541; the patent long predates the Federal Circuit and any live enforcement.

I'll search for litigation involving US patent 135541 specifically.

Let me check a few more targeted sources to confirm.

Litigation Search Report — U.S. Patent No. 135,541

Patent identified: US 135,541 — "Improvement in Compression Basin-Faucets," granted February 4, 1873 to William Gordon of Philadelphia, Pennsylvania (assignor of two-thirds to Andrew McCambridge and Thomas Kennedy). Source: https://patents.google.com/patent/[US135541](/patent/US135541)/en

Result: No litigation found

No litigation is known involving U.S. Patent No. 135,541. My searches returned zero cases — in any court, in any era — in which this patent number appears as an asserted patent, a patent-in-suit, or the subject of an IPR/PGR/CBM proceeding.

What I searched

Critical caution — do not conflate with similarly numbered patents

The searches did surface several "135"/"541"-adjacent items that are different patents and must not be reported as litigation of US 135,541:

• US 7,595,385 — an unrelated 2009 biotech patent whose PDF happened to contain the sequence-identifier string "135541."
• JP HEI 1-135541 — a Japanese patent publication cited as prior art in US 5,155,994; not the US patent at issue.
• WO 2010/135541 — a PCT publication (AU 2010249802 B2 family); unrelated.
• The VirnetX v. Apple '135 patent (E.D. Tex. 6:12-cv-00855) is US 6,502,135, not 135,541.
• The RPX-reported complaint referencing an Apple '135 patent concerns a modern patent, not 135,541.

None of these involve U.S. Patent 135,541.

Contextual reasons no litigation exists

1. Age and term. The patent issued February 4, 1873 and reached its anticipated expiration on February 4, 1890 (per the Google Patents legal-status record). Any enforcement action would have occurred in the late 19th century.
2. Pre-database era. Federal district court records from the 1870s–1880s are largely not indexed in modern electronic litigation databases (Unified Patents, RPX Insight, CourtListener, PACER). PACER coverage begins in the late 1980s/1990s; CourtListener's historical coverage is spotty for 19th-century patent cases.
3. No modern proceedings. An 1873 patent cannot be the subject of an IPR, PGR, or CBM (AIA post-grant proceedings apply only to patents with effective filing dates meeting the statutory criteria), and it is long expired, so infringement (and thus infringement litigation) is legally impossible today.

Bottom line

For the format requested — plaintiff(s), defendant(s), jurisdiction, case number, filing date, outcome — there are no entries to report. I cannot supply case names or docket numbers for a case that I found no evidence of, and I will not fabricate them.

Confidence: High that no modern litigation exists (the patent expired in 1890). Moderate as to the 1873–1890 window: there may have existed historical infringement suits that predate modern electronic dockets and would require manual review of 19th-century federal court records (e.g., the Federal Cases reporter, nineteenth-century Pennsylvania circuit/district court archives) to rule out definitively. I have not performed that archival search and cannot state with certainty that none occurred.

If you'd like, I can next attempt targeted archival queries (e.g., "Gordon v." faucet, 1873–1890, E.D. Pa.) to probe the historical window.

I'll verify the structured-data null result against live sources before concluding.

Confirming against PTAB docket aggregators directly.

PTAB / AIA Trial Proceedings Report — U.S. Patent No. 135,541

Proceedings overview

Total AIA trial proceedings on file: 0. There have been no Inter Partes Reviews, no Post-Grant Reviews, and no Covered Business Method reviews ever filed against U.S. Patent No. 135,541 ("Improvement in Compression Basin-Faucets," William Gordon, issued 1873-02-04). The breakdown by status is therefore trivially: active — 0; claims invalidated — 0; claims sustained — 0; settled — 0; institution denied — 0.

Bottom line for a defendant: there is no IPR record to lean on and no PTAB-created estoppel to exploit. All six claims of the patent are UNTESTED at the Board — but "untested" here does not mean "hardened," because the patent died of old age in 1890 and no rational petitioner would ever file. The practical posture is not "the patent has survived and is hardened"; it is "the patent is a historical artifact, not an assertion asset — if anyone sends you a demand letter citing US 135,541, you are dealing with a fraud or a crank, not a patent troll with an IPR record."

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Per-proceeding detail

No proceedings exist to report

The canonical structured block ("PTAB proceedings on file") records that the USPTO Open Data Portal API returns no AIA trial proceedings for this patent. I treated that NULL as authoritative and attempted to falsify it with live search. It survived:

Docket aggregators that index PTAB filings by challenged patent number (PTAB E2E / PTActs — https://ptacts.uspto.gov, Docket Alarm's PTAB docket, Unified Patents litigation caselist) returned no proceeding naming this patent. I am not going to generate a proceeding number, petitioner name, or panel to fill this section — no proceeding exists, and inventing one would be the worst possible failure mode in a defensive diligence memo.

Do-not-conflate list (the near-miss identifiers that pollute search)

These surfaced repeatedly and are not US 135,541:

• WO 2010/135541 (PCT/US2010/035586; AU 2010249802 B2 family) — a biotech/CNP-variant publication. Its number shares four digits with the patent at issue and it appears in the same search strata.
• JP HEI 1-135541 — Japanese publication cited as prior art in US 5,155,994.
• US 7,595,385 — a 2009 patent whose sequence listing happens to contain the string "135541."
• The VirnetX '135 patent is US 6,502,135 — a different patent entirely.

This is consistent with the caution already recorded in the litigation section of this analysis; I flag it as reinforcing, not contradicting, that section.

Why the null is legally structural, not just a database gap

1. PGR is unavailable as a matter of law. 35 U.S.C. §§ 321–329 post-grant review applies only to patents with an effective filing date on or after the AIA's first-inventor-to-file cutoff (2013-03-16). A patent granted 1873-02-04 cannot be the subject of a PGR.
2. CBM was unavailable in practice and is now sunset entirely. AIA § 18 covered business method review was limited to patents with claims directed to financial products/services and to pre-AIA effective filing dates — a swing-compression basin faucet fails the "financial services" prong by any reading of Unwired Planet v. Google. The program also expired 2018-09-16 pursuant to § 18(a)(3)(A).
3. IPR is the only legally possible vehicle, and it is economically dead. There is no statutory date bar in § 311 that would exclude an 1873 patent, and the Board has historically instituted on expired patents where past damages remained live. But the patent expired 1890-02-04 (its anticipated expiration per the Google Patents legal-status record), so there is no ongoing infringement, no § 284 damages tail, no § 315(b) one-year clock running, and no licensing revenue for anyone to protect. The expected value of a petition is negative by the cost of the filing fee alone.

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Strategic summary

Claim status. US 135,541 carries six claims, all of which remain exactly as granted — never canceled, never amended, never construed by the Board or (so far as the record shows) by any court:

• Claim 1 — cap B with screw-socket D in combination with stem C.
• Claim 2 — cap B with screw-socket D and stuffing-box h, with screw-stem C and packing-ring i.
• Claim 3 — upper valve-seat b' on the lower end of screw-socket D, with upper valve E'.
• Claim 4 — annular chamber d in the lower end of screw-socket D, with cross-opening e of the valve-stem.
• Claim 5 — screw-cap H, ball G with annular space u, and screw-stem C with side-opening o.
• Claim 6 — openings j and pin m, with the upper end of the screw-stem and ball G of the nozzle.

(Claim language above is read from the printed claim set; the Google Patents OCR of the claim block is garbled, so any quoting for a brief should be taken from the original Patent Office printing.)

Because the patent has never been through an AIA trial, there are no CANCELED claims, no SUSTAINED claims, and no substitute claims. Every claim is UNTESTED — but "untested" carries none of its usual defensive anxiety when the patent's enforceable life ended 136 years ago.

Estoppel landscape — there is none. 35 U.S.C. § 315(e)(2) estoppel attaches only to a petitioner that reaches a final written decision. No FWD was ever issued, so no petitioner, real party in interest, or privy is estopped from anything. There is likewise no § 325(e)(2) estoppel. For a defendant today, this is a non-issue: the limiting constraint on your defenses is the patent's expiration and the resulting absence of any remedy under 35 U.S.C. §§ 271 and 284 — not estoppel. If, hypothetically, someone purported to assert this patent now, your defenses would be led by § 286's six-year damages bar (which reaches back only to 2020, well after the 1890 expiration), lack of an enforceable right given expiration, and the traditional invalidity defenses of §§ 102/103 against the enormous body of intervening prior art — not by anything the Board has already ruled on.

Pattern signals. None are present, because there is no record to analyze. No repeat petitioner, no serial-filing behavior, no patent-owner appeal practice, no defensive aggregator involvement, and no Unified Patents challenge. Worth noting: a defensive aggregator like Unified Patents targets currently asserted patents to protect members from demand letters. US 135,541 has never generated an assertion campaign that would attract one. The absence of PTAB activity here is not a "sleeper patent" signal — it is the predictable signature of a 19th-century patent that has been in the public domain for well over a century.

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Recommended next steps

If no PTAB activity exists — say so plainly. It does not exist. There is no institution decision deadline, no oral hearing date, no statutory 1-year FWD clock, and no appeal docket to track, because no trial was ever instituted. PTAB's own decisions database (https://www.uspto.gov/patents/patent-trial-and-appeal-board/ptab-decisions) and the PTActs system of record (https://ptacts.uspto.gov) contain nothing for this patent number — that is the answer, and it is a defensible one.

If you are facing a demand letter citing US 135,541:

1. Verify the number before doing anything else. Check the letter's patent number against https://patents.google.com/patent/[US135541](/patent/US135541)/en. A legitimate assertion cannot rest on an 1873 patent that expired 1890-02-04. The likeliest explanations are (a) a typographical/OCR transposition of a modern patent number, (b) confusion with WO 2010/135541 or the VirnetX US 6,502,135 patent, or (c) a bad-faith demand. Document which one it is.
2. Preserve the § 286 point. Under 35 U.S.C. § 286, no damages are recoverable for infringement occurring more than six years before the filing of the complaint. Combined with the 1890 expiration date, this forecloses any damages theory categorically.
3. Do not spend on an IPR. Filing a petition against this patent would be a waste of fees, and there is no parallel litigation posture that a PTAB win would improve.
4. Confirm the historical record only if the stakes justify it. The one genuinely open question — flagged in the litigation section and worth repeating here rather than repeating its analysis — is whether any 19th-century infringement suit was ever filed. That question is answerable only by manual archival review (Federal Cases reporter, Pennsylvania circuit/district archives for the 1873–1890 window). No AIA-track tool will ever surface it, and I have not performed that search. If a counterparty claims a historical litigation estoppel or a judgment, demand the citation rather than accepting the claim.

Confidence. High that zero AIA trial proceedings exist — this is supported both by the canonical ODP null and by independent search across PTAB dockets and aggregators, and it is structurally compelled by the PGR/CBM statutory limits and the patent's 1890 expiration. High that no IPR, PGR, or CBM is currently pending. Moderate only as to the 1873–1890 window and any pre-AIA, pre-database enforcement history, for the same archival reasons noted above.

I'll search for the assignment record for this patent.

Let me try additional targeted searches.

Let me probe the inventor's business and the USPTO assignment database coverage.

Analysts' process note

Two instructions in this task conflict, and I'm flagging it rather than silently picking one. The "Assignment timeline" instruction says to stop after that section if Assignment Center has no records, but the required output order runs through the NPE signals and a mandatory Verdict. I've supplied the full requested order, with the post-timeline sections expressly marked as not derived from any assignment record (there is none).

Also flagging one cross-reference discrepancy with the previously generated summary: that section lists the witness as "Thomas S. Bewley." The OCR in the Google Patents text reads "THOMAS S. BEWLEY," but the Google Books compilation of the same period renders the identical witness line on Gordon's 1872 patent as "THOMAS J. BEWLEY." One of the two is an OCR error; I cannot resolve which. This does not affect the ownership chain.

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Inventors

William Gordon, of the city of Philadelphia, State of Pennsylvania. Sole named inventor; no co-inventors appear in the specification, the claim signature block, or the record.

Employer at time of filing: not determinable. The Letters Patent give only a city of residence, which was the universal 19th-century convention — assignee-of-record fields for corporate employers simply do not exist in this format. I found no evidence that Gordon was an employee of any firm. What the record does show is that he was a repeat, independent inventor in this exact art:

• He obtained U.S. Patent No. 127,341, "Improvement in Swing-Compression Basin-Cocks," dated May 28, 1872 — the year before the patent at issue. The Google Books compilation of the period shows the identical witness line ("STEPHEN USTICK, THOMAS J. BEWLEY") on that 1872 patent.

Unusual-pattern check: not applicable. A single inventor with no corporate assignee cannot exhibit "all inventors departing within 12 months." The closest observable pattern is the opposite — continuity of the same witnesses and the same narrow subject matter across at least two grants one year apart, which is consistent with a solo Philadelphia mechanic/inventor operating a small shop rather than with a corporate R&D group. I state that as an inference from the witnesses and subject matter, not as a documented fact; I could not find a business directory entry, city directory listing, or firm name for Gordon.

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Original assignee

Nuance that matters here: the patent issued to William Gordon as patentee, but its face carries a partial assignment. The Letters Patent are headed:

"WILLIAM GORDON, OF PHILADELPHIA, PENNSYLVANIA, ASSIGNOR OF TWO-THIRDS HIS RIGHT TO ANDREW MCCAMBRIDGE AND THOMAS KENNEDY, OF SAME PLACE"

So the ownership position at grant was:

All three were individuals; "of same place" = Philadelphia. This is a pre-issuance assignment executed so that the assignees are named on the printed patent — standard 19th-century practice when backers financed an inventor's filing.

• Products embodying the claims: The invention is a swing-compression basin faucet in which the nozzle swings back to either side and the water is cut off in each back position, flowing only when the nozzle points forward. Given that Gordon had an earlier patent in the same narrow art (No. 127,341) and carried a two-thirds assignee group, the most plausible reading is that something was manufactured under these patents by or for the assignees. But I have no evidence — no catalogue, no trade mark, no advertisement found — so I will not report a shipped product as fact. Unclear.
• Primary line of business of the assignee group: Not determinable. No firm name, no corporate form, no business purpose appears in the record.
• Current status: All three individuals and any unincorporated venture are long gone; the patent expired 1890‑02‑04. Gordon, McCambridge, and Kennedy are not traceable as operating entities, and no corporate successor is identified anywhere in the record.

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Assignment timeline

The USPTO Assignment Center has no assignment records for this patent. My searches surfaced no reel/frame entry — and none for the assignee names McCambridge or Kennedy.

This is the expected result, not a search failure. The Assignment Center's electronic reel/frame corpus is a post‑mid‑20th‑century artifact; the Patent Office's recording practice dates to 1837, but those pre-modern deed books are not in the searchable online index, and this 1873 grant was recorded 82 years before the earliest typical online entries. So the record is silent for a structural reason: the chain is too old to have been keyed into the system.

(Caveat on my own confidence: the widely repeated statement that online assignment coverage begins around 1955 is what I am relying on; I was not able to independently verify that cutoff date in this session, and I did not directly query the Assignment Center interface — my evidence is the absence of any returned reel/frame record plus the intrinsic age of the patent.)

Therefore the closest thing to an assignment record is the face-of-patent recital itself:

• Executed on or before 1873‑02‑04 / "recorded" only by being printed on the Letters Patent — Reel/Frame: none.
  • Conveyance: Assignment (partial — two-thirds interest)
  • Assignor: William Gordon, Philadelphia, Pennsylvania
  • Assignee: Andrew McCambridge and Thomas Kennedy, both of Philadelphia, Pennsylvania (as tenants of the two-thirds interest; the division between them is not stated)
  • Correspondent: none on record. Pre‑1950s practice did not name an attorney correspondent in the conveyance; the only names attached are the attesting witnesses, Stephen Ustick and Thomas S. J. Bewley (OCR ambiguous between S and J). No repeat-player correspondent exists to flag, because no correspondent field exists.
  • Context: pre-issuance financing / partial transfer to backers — the classic 19th-century pattern in which an independent inventor assigns a controlling fractional interest before grant.

No subsequent recorded assignment of any kind appears — no merger, no change of name, no security agreement, no release, no NPE transfer. Nothing happens to this patent after 1873 in any record I can reach.

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Timeline diagram

timeline
    title Ownership of US 135541
    1872 : Related Gordon patent 127341 issued
    1873 : Patent 135541 granted to William Gordon
         : Two thirds assigned to McCambridge and Kennedy
    1890 : Patent term expires

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NPE / troll-pattern signals

Every signal below is assessed against an 1873 grant that expired in 1890. I mark "not present" only where the record affirmatively shows the thing didn't happen; where the very concept is inapplicable, I say so rather than mislabeling it.

1. Shell-entity transfer — Not present. No assignment to any entity of any kind is recorded, per the Assignment Center silence and the single face-of-patent conveyance of 1873‑02‑04. There is no LLC, no suspect suffix, no registered-agent address. Nothing to cite because nothing exists.

2. Known asserter in the chain — Not present. The only assignees ever named are Andrew McCambridge and Thomas Kennedy, private individuals in Philadelphia in 1873. None of the listed asserters (Acacia, Marathon, IV, IPNav, Wi‑LAN, Mosaid/Conversant, Vringo, Pendrell, Innovatio, MPHJ, Lumen View, Round Rock, Erich Spangenberg entities, etc.) could possibly appear — the earliest of them postdates this patent's expiration by roughly a century.

3. Repeat correspondent across the chain — Not present; structurally impossible. The one conveyance carries no correspondent of record. There is a chain length of one, so recurrence cannot occur. This is the signal the task flags as most useful for modern shell chains, and it is simply absent here — as it is for every pre‑20th‑century patent.

4. Cascading transfers — Not present. One transfer in 1873, none thereafter. No chained LLCs, no shared correspondent addresses, no <24-month window.

5. Pre-litigation transfer — Not present. There is no infringement suit naming this patent (consistent with the previously generated litigation section: zero cases found, Federal Circuit not created until 1982). With no suit, no pre-suit transfer window can exist.

6. Bankruptcy fire-sale — Not present. No assignor or assignee is a company, so there is no Chapter 7/11 estate from which these rights could be sold.

7. Privateering — Not present. No operating company transferred anything to anyone.

8. Defensive aggregator (anti-NPE) — Not present. The chain does not terminate at RPX, AST, LOT, Unified Patents, or OIN. It terminates at three private individuals in 1873, and then at expiration on 1890‑02‑04.

A note on what a modern analyst should not do here: the temptation is to map this 19th-century structure onto modern NPE vocabulary — an inventor retaining one-third while two-thirds goes to outside parties can superficially resemble a "transfer to a non-practicing holder." That mapping would be anachronistic and unsupported. The 1873 fractional assignment is ordinary pre-grant financing, and there is no evidence of litigation, licensing revenue, or assertion at any point in the 17-year term. I decline to score it as a signal.

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Verdict

Insufficient data — specifically the "only the original assignment" variant of that category.

Justification: The single ownership event of record is the face-of-patent assignment of two-thirds of William Gordon's right to Andrew McCambridge and Thomas Kennedy, effected on or before 1873‑02‑04, with no reel/frame, no correspondent, and no subsequent transfer of any kind. The Assignment Center index contains nothing for this patent, and the 17-year term closed on 1890‑02‑04 (Google Patents legal status: "Expired – Lifetime"), so there is neither an assignee to characterize as an NPE nor any post-issuance chain to analyze. No NPE or troll signal can be scored as present, and I found no evidence either that the assignee group shipped a product — which, had it existed, would have supported an "Operating-company assertion" call. There is simply nothing here to classify beyond the 1873 fractional grant.

Verification link: https://assignmentcenter.uspto.gov/ — search by patent number 135541. Note that per USPTO's own notice encountered in this session, the legacy URLs assignments.uspto.gov and assignment.uspto.gov are being retired as of February 2, 2026, so use the assignmentcenter.uspto.gov address above. Companion record: https://patents.google.com/patent/[US135541](/patent/US135541)/en (legal events tab showing only the 1873 grant and the 1890 expiration — no assignment events).

I'll verify the citation record for this specific patent before analyzing prior art.

Let me probe the record's citation fields and the nearest pre-1873 references.

Prior-Art Report — U.S. Patent No. 135,541

Bottom line

U.S. Patent No. 135,541 has no patent citations — zero cited references of any kind. The authoritative record (https://patents.google.com/patent/[US135541](/patent/US135541)/en) contains no "Citations," no "References Cited," no "(56)" field, and no "Cited By" field. Therefore the literal answer to "which claim(s) does each cited reference anticipate" is: there is nothing to map. I will not manufacture citations to fill the table.

What the record does contain is a Google-generated "Similar Documents" list (21 items) and auto-extracted "Prior art keywords" — neither of which are citations under 35 U.S.C. § 102. Below I (a) document that forensic finding, (b) screen the Similar Documents list by date to isolate the only items that could even be prior art to a Feb. 4, 1873 grant, and (c) give best-effort § 102 mappings with explicit confidence limits.

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1. Record forensics — why the citation count is zero

This is expected and not a data gap: pre-1952 U.S. patents were not printed with a "References Cited" section, and 19th-century Patent Office practice imposed no duty on the applicant or examiner to list references on the face of the grant. My searches for US135541A citation/cited-by data returned empty result sets (0 results), consistent with the page containing none. USPTO's full-text collections likewise carry no citation data for this era of grants.

False positives encountered and rejected (per the "do not return similar numbers" instruction): the search string 135541 surfaced EP 2 196 541 / EP 2 196 220 family members from the front page of US 11,359,194 (https://patentimages.storage.googleapis.com/ef/44/74/40f11ee6d5a644/US11359194.pdf), and a CourtListener hit for Johnson Co. v. Pennsylvania Steel Co., 3d Cir. 1895, which concerns US 333,474 (a street-railway switch) — a digit-transposition artifact, not US 135,541. Neither is reported below as prior art.

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2. The nearest available analogues — pre-critical-date candidates only

For a patent granted February 4, 1873, the governing novelty provision is Rev. Stat. § 4886 (Patent Act of 1870), which asks what was known/used in the U.S., or patented or described in a printed publication anywhere, before the applicant's invention, plus the two-year public-use/on-sale bar in the same section. Only items dated before Feb. 4, 1873 can serve. Four items in the record's Similar Documents list qualify on date:

Critical limitation I must state plainly: I was unable to retrieve the specification text or drawings of US 127,340, 131,556, 59,346, or 43,125 in this session — my retrieval calls were terminated at the step limit. The mappings above are hypotheses keyed to title, date, and field only. Anticipation under § 102 requires that every element of the claim, arranged as recited, be found in a single reference; because each claim here is a combination claim (all six are stand-alone; none depends from another), the analysis turns entirely on disclosures I have not read. I therefore do not assert that any of these references anticipates any claim. Any of them could, on inspection, disclose the opposite — e.g., US 59,346's diaphragm construction would tend to lack the stuffing-box + packing-ring combination of claim 2.

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3. Post-grant items (cannot be § 102 prior art to this patent)

The remaining 17 Similar Documents all post-date the Feb. 4, 1873 grant and are therefore not available as prior art against US 135,541. Listed for completeness because one of them is arguably the closest conceptual match:

• US 169,952 A — "Improvement in combined compression and swing cocks," 1875-11-16. Terminology nearly identical ("combined compression and swing"). Because it post-dates the grant by ~2 years 9 months, it cannot anticipate or render obvious the claims here; it is at most evidence of a crowded art. Flagging it because a future analyst searching by keyword will inevitably surface it.
• US 136,851 A "Improvement in stop valves, cocks," 1873-03-18 (~6 weeks after the grant).
• US 142,350 A "Improvement in stop-cocks," 1873-09-02; US 155,198 A self-closing faucets, 1874-09-22; US 167,010 A globe-valves, 1875-08-24; US 167,751 A stop-cocks, 1875-09-14; US 181,267 A stop-valves, 1876-08-22; US 208,986 A valves, 1878-10-15.
• All later items (US 255,666 A 1882 → US 1,180,482 A 1916) are 20th-century-adjacent and wholly unavailable.

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4. Discrepancies and flags (per operating rules)

1. Date inconsistency across prompts. This task states "Current Date: April 26, 2026," while the system context states today is 2026-09-29 and the authoritative record is stamped fetched 2026-09-29T10:15:59.722Z. I use the record as ground truth and flag the mismatch rather than silently harmonizing. It does not affect any 1873 reference date.
2. Unresolved conflict over US 127,340's identity. The Google Patents record titles US 127,340 A as "Improvement in swing-compression basin-cocks" (1872-05-28). A contemporaneous Patent Office volume listing grants for the week ending May 28, 1872 (Patents No. 127,136–127,401) shows the entry "127,340 Collar, (109,) Godfrey and Fuller, (reissue)" (https://books.google.com/books/download/Specifications_and_Drawings_of_Patents_I.pdf?id=6sc6AQAAMAAJ&output=pdf#101#1). These two search-derived sources contradict each other — one indicates a collar patent to Godfrey and Fuller, the other a swing-compression basin-cock. The "(reissue)" and "(109,)" annotations may indicate a reissue-index section rather than the grant itself, but I could not resolve this and am not auto-correcting either source. If the title-attribution is wrong, US 127,340 collapses as prior art and the entire pre-1873 candidate set would be limited to US 131,556, US 59,346, and US 43,125.
3. No filing or application date exists in the record (application-number field blank). Because the § 4886 novelty test keys to the date of invention and the two-year bar keys to the application date, the precise prior-art window cannot be computed. Any reference dated 1871–1873 is therefore trapped in an irreducible ±uncertainty zone.
4. Claim 5's "u" vs. "n" (carried over from the earlier summary): the claim recites the ball's annular space as u; the specification calls it n. This OCR degradation affects the wording of claim 5 and consequently any element-by-element comparison against a candidate reference.
5. § 102 / § 103 mapping is anachronistic — but here's the mapping requested. § 103 was not enacted until 1952; 19th-century practice used "want of invention." Functional equivalences: modern § 102(a)(1)/(a)(2) ↔ Rev. Stat. § 4886 (knowledge/use in the U.S.; patented or described in a printed publication before invention); modern § 102(b) ↔ Rev. Stat. § 4886's two-year public-use/sale bar; § 103 ↔ judicially developed "invention." Applying "35 U.S.C. § 102" to this patent is a convenience convention, not a legal reality.

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5. What a genuine § 102 analysis would require

Because there are no citations to analyze, completing this task requires constructing the prior-art set rather than reading a citation list:

1. Pull full specifications/drawings for US 131,556 (1872), US 59,346 (1866), US 43,125 (1864) — and resolve the identity of US 127,340 — via the Patent Office's annual Specifications and Drawings of Patents volumes for 1864, 1866, and 1872 (available as the digitized volumes already surfaced in search).
2. Search contemporaneous non-patent sources: 1860s–1870s plumbing-trade catalogs (basin-cock/cistern-cock cuts), Scientific American, and Journal of the Franklin Institute, for plain swing-compression basin cocks, which are the most plausible real anticipators of claims 1–4.
3. For each candidate, chart elements claim-by-claim against the six combination claims (cap B + screw-socket D; stuffing-box h + packing-ring i; upper seat b′ on socket's lower end + upper valve E′; annular chamber d + cross-opening e; screw-cap H + ball G annular space n + stem side-opening o; indexing openings j + pin m).

Confidence statement

• High confidence that US 135,541 contains no citations and no cited-by entries — verified directly against the authoritative record and corroborated by empty search result sets.
• High confidence that all 17 post-1873-02-04 Similar Documents are legally unavailable as § 102 art against this patent.
• Low confidence in any anticipation mapping for the four pre-1873 candidates; those characterizations rest on titles and dates alone, and one (US 127,340) is subject to a documented source conflict. I have not read their disclosures and do not assert anticipation of any claim.

Primary source for all patent data: https://patents.google.com/patent/US135541/en (fetched 2026-09-29T10:15:59.722Z).

I'll verify the prior-art references available for this patent before analyzing.

Obviousness Analysis — U.S. Patent No. 135,541

"Improvement in Compression Basin-Faucets" (William Gordon, Philadelphia) — granted February 4, 1873

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0. Threshold caveats before applying § 103 (read these first)

0.1 The statutory basis is anachronistic. 35 U.S.C. § 103 was enacted by the Patent Act of 1952, effective January 1, 1953. It is not retroactive; it does not supply a validity standard for a patent granted February 4, 1873. This grant is governed by § 24 of the Patent Act of 1870, as construed under Hotchkiss v. Greenwood, 52 U.S. (11 How.) 248 (1850) (whether the variation required "more ingenuity and skill … than were possessed by an ordinary mechanic acquainted with the business"), and — by the time of the 1870s–80s litigation era — by the higher "flash of creative genius" gloss (Cuno Engineering Corp. v. Automatic Devices Corp., 314 U.S. 84 (1941)), which Graham v. John Deere Co., 383 U.S. 1 (1966), held was not the law. I run the requested § 103 analysis below as a hypothetical grading exercise, because Graham characterized § 103 as codifying pre-existing judicial law — so the analysis is instructive, but it is not the correct legal test for this patent, and any conclusion here has no operative legal effect.

0.2 There is no live controversy. The Google Patents record shows "Anticipated expiration 1890-02-04," status "Expired – Lifetime." Obviousness would matter only in a hypothetical, an academic exercise, or (very marginally) in a historical invalidity defense in a suit filed before 1890.

0.3 The record's "prior art date" is useless as a critical date. The page stamps prior art date 1873-02-04 — the grant date. That is a record key, not a prior-art date. The application number and filing date fields are blank, so the applicant's invention date is unknown and the true critical date cannot be fixed. Conservatively, only references published comfortably before mid-1872 are safe prior art.

0.4 Provenance discipline. The page's "Prior Art" content consists of (a) algorithmically extracted prior art keywords — nozzle, screw, stem, faucets, valve (these are Google's extraction, not examiner citations), and (b) a "Similar Documents" table, which is machine-generated similarity, not a references-cited list or an examiner's search. The original 1873 printed patent carries no References Cited section, and the fetched snapshot shows no "Cited By" section. Where I introduce a reference not on that table, I say so.

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1. Scope and content of the prior art — what the page actually supplies

The "Similar Documents" table contains 25 U.S. grants. Classifying by date against the February 4, 1873 grant:

Key analytical point: 21 of 25 "similar documents" post-date the grant. Only US43125A, US59346A, US127340A (and conditionally US131556A) are usable as § 103 art. That materially weakens the page's prior-art base and is the single most important scope finding.

Additional pre-1873 art I verified independently (not on the page): US124,840 — John Maclaren, "Improvement in Compression-Cocks," patented March 19, 1872 (Scranton, Pa.). Maclaren discloses a cock in which the stem B has "a central orifice running entirely through it," a screw-thread on the lower end of a metallic guide seated in the valve ball, a hollowed stem end receiving part of the ball, and brass caps on the ball, the whole arranged so the ball can be raised "by turning the stem." (Verified text: patentimages URL US124840.pdf.) This is directly on point for the claim 4/5 subject matter and is my strongest located reference.

Filed away but instructive: US181,929 (Forns & Mooney, "Basin-Cocks," Sept. 5, 1876) — cap C with a stuffing-box b in its lower end, a hollow valve-rod D with "a series of perforations, x, y, for the admission of water into the same," a chamber E screwed on the rod's upper end, and a collar m with notches engaging pins i t acting "as stops for the turning of the nozzle." That is a near-element-for-element echo of claims 1, 2, 4 and 6 — three years after Gordon. It is not prior art to '541 and cannot be combined against it, but it is powerful evidence that these features were the routine design vocabulary of the art, which bears on the Graham "level of ordinary skill" factor.

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2. Level of ordinary skill in the art (Graham factor 2)

A person having ordinary skill in 1872–73 would be a brass-foundry/plumbing mechanic: competent in hand-tapping and die-cutting threads, seat grinding, leather- and rubber-packed stuffing-boxes, screw-down (compression) valve design, ground-key cocks, and the then-current family of "swing" and "basin" cocks that rotated a nozzle over a wash basin. He would know the ordinary compression faucet bonnet, the union nut, and the ball-and-socket pipe joint. He would be under strong market pressure: the 1870s indoor-plumbing boom produced a dense, fast-moving faucet art (the presence in the record of three separate "swing/compression cock" proposals in 1872–75 — US127340A, US169952A, and Gordon's own — is itself evidence of a crowded, competitive field, i.e., a KSR "design incentive" and finite-solution-space situation).

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3. Claim-by-claim analysis

Claim 1 — cap B with screw-socket D + stem C

Literal scope: mounting the threaded stem through a socket formed in the water-chamber cap, with no separate bonnet or bushing.

Obviousness. This is the ordinary compression-faucet bonnet. The patentee concedes as much: the specification says the lower valve/seat arrangement "is the same as in ordinary faucets." The art is replete with cap-threaded stems — e.g., Maclaren's stem threaded through the cock body (US124,840), Vreeland & Lathrop's stem B projecting "through the case or seat" of a gage-cock (US131,799, Oct. 1, 1872), and, in terms of what was "ordinary," the description in US174,551 (McKenzie, 1876) of "an ordinary globe compression valve" in which the cap B′ has a hole bored longitudinally "provided with an internal screw, to and within which the valve stem D is fitted."

Rationale (KSR) — (A) combining known elements (cap + internally threaded socket + threaded stem) according to known methods, yielding the predictable result. The only asserted benefit is a longer, housed thread engagement — a pure design choice.

Strongest counter. None in the record. Claim 1 is the weakest claim in the patent.

Claim 2 — cap B + screw-socket D + stuffing-box h, with stem C and packing-ring i

Literal scope: the socket carries its own stuffing-box so the screw threads are shut off from water ("whereby the screw is fully protected against the passage of water through it").

Obviousness. Packed stuffing-boxes for rotating and reciprocating stems were decades-old boiler/steam-fitting practice by 1872 and are shown in the very same faucet art — Maclaren's screw-stem cocks, and (post-dating '541 but demonstrating ordinariness) US181,929's stuffing-box b "in the lower end of the plug" through which the valve-rod passes, and US124,840's arrangement.

Rationale (KSR) — (C) use of a known technique (packing a stem with a gland and ring) to improve a similar device in the same way, and (B) simple substitution of the known packed bearing for an unpacked one. The claimed location of the packing below the threaded socket is dictated by the stated function (protecting the threads) — the arrangement is the only sensible one once the water is known to travel up the socket.

Secondary consideration check. No evidence of commercial success, long-felt need, failure of others, copying, or industry praise appears in the record. The only ownership datum — Gordon's assignment of two-thirds to Andrew McCambridge and Thomas Kennedy — is a sale of rights, which is legally neutral and not probative of nonobviousness.

Claim 3 — upper valve-seat b′ on the lower end of the screw-socket D + upper valve E′

Literal scope: the socket's own lower terminus, projected into the valve chamber, doubles as the second valve seat.

Obviousness. Seat-on-the-end-of-a-screwed-member is standard globe-valve construction — the seat surface was conventionally formed on an inserted ring, septum, or the lower edge of a screwed-in part (see the seat-b′/washer arrangement described in US174,551 at element B, and the general office of an inserted screwed bushing). What Gordon adds is only the identity of the socket with the seat: one part performing two functions.

Rationale (KSR) — (A) and (D): applying a known construction technique (form the seat on the screwed-in member) to a known device ready for that improvement, with predictable results. The functional payoff the specification asserts — that the end of the socket "may form a seat for the upper valve E when the nozzle F is thrown back to the left," so the faucet is closed at both swing extremes — flows directly from the pre-existing art of swing cocks in which the nozzle's backward positions are the "off" positions (the title of US127340A, "swing-compression basin-cocks," establishes that class one year before Gordon).

Nonobviousness argument available. The two-opposed-valves-on-one-screw-stem concept (screwing one direction closes the lower valve while opening the upper, and vice versa, with both open only when the nozzle is forward) is a genuine combination, not a mere collocation: the single rotary actuation derived from the nozzle swing produces a shut-off at either extreme of swing. That is the patent's best argument, and it is the reason claim 3 is the claim's real center of gravity.

Rebuttal. The problem of "shut it off whichever way the nozzle is thrown" is the raison d'être of the swing basin cock as a class, and the admitted ordinary faucet already closed on the backward-right swing. Extending shut-off to the opposite swing by adding a second seat on an existing part is the kind of "predictable use of prior art elements according to their established functions" that KSR Int'l Co. v. Teleflex Inc., 550 U.S. 398, 417 (2007), condemns. Additionally, under the pre-1952 aggregation doctrine (cf. Lincoln Engineering Co. v. Stewart-Warner Corp., 303 U.S. 545 (1938)), each element here still performs only its own function.

Claim 4 — annular chamber d in the lower end of the screw-socket D + cross-opening e of the valve-stem

Literal scope: water entering the annular space at the socket's lower end passes laterally through the stem's cross-opening into the stem's central passage f.

Obviousness. This claim is squarely met by Maclaren, US124,840 (1872-03-19), verified above: a stem with "a central orifice running entirely through it," into which a guide carrying the ball passes, and the stem having a "shoulder, b′," at its lower end. Once the stem is the flow conduit (Maclaren), some lateral port is unavoidable; making the socket bore slightly larger than the stem so as to leave an annulus is the ordinary way to ensure the port is fed irrespective of rotational position. The same solution recurs in the art — US181,929's "series of perforations, x, y" admitting water into a hollow rod "within the valve-chamber"; US131,799's hollow egg-shaped valve with an internal cavity fed by a port.

Rationale (KSR) — (A), (B), and "obvious to try" with a finite number of identified, predictable solutions: the artisan designing a hollow flow-through stem must provide an inlet; a cross-drilling fed by a surrounding annulus is one of a handful of predictable options (the alternatives being slots, a side port alone, or an open stem end).

Note on drafting: claim 4 claims the annulus and the cross-opening as a combination, but does not positively recite the central passage f or the nozzle — arguably a drafting gap rather than a scope advantage.

Claim 5 — screw-cap H + ball G of the nozzle with annular space (recited as "u"; the specification calls it n) + stem C with side-opening o

Literal scope: the nozzle's ball is held to the tapered upper end of the stem by a screw cap, with an internal annulus keeping the stem's side-opening in continuous communication with the nozzle passage "when the nozzle is in any position."

Obviousness. This is a hollow ball-and-socket swivel joint confined by a union nut — both elements ancient in pipe-fitting and cock-making: ball-and-socket flexible joints, and cap/union-nut confinement of a joint (the patent itself calls the union a "screw-cap"). Maclaren supplies the hollow stem with a through-orifice and the screw-threaded connection between stem and a valve element; Vreeland & Lathrop supply a valve element with an internal cavity and a port.

Rationale (KSR) — (C)/(F) design choice: given a hollow stem that must feed a swinging nozzle, a swivel with a screw cap is the predictable fitting; the annular space n is dictated by the function of maintaining communication through the full swing arc, i.e., a dimensional/design choice (make the internal groove wide enough) rather than an inventive step. Claim 5 also carries a self-inflicted wound: the cap H is claimed, per the specification, "to provide for its adjustment," which overlaps the separately claimed pin-and-openings adjuster of claim 6 — an over-lapping, uncoordinated claiming of the same function, characteristic of a mere aggregation.

Caveats (flagged in the earlier sections and repeated here): the claim text as digitized reads "an annular space, u," while the specification identifies the ball's annular space as n and the side-opening as o. I treat "u" as an OCR corruption of "n"; I cannot verify the original printed character. Claim 5's viability therefore rests on a reconstructed reading and is the most fragile part of this analysis.

Claim 6 — vertical openings j + pin m, with the upper end of the screw-stem and the ball G of the nozzle

Literal scope: an indexable pin-and-hole adjuster that fixes the angular relation between nozzle and stem so the nozzle reaches its correct backward position exactly when a valve seats.

Obviousness. Pin-and-notch/pin-and-hole stops to limit and index the rotation of a cock handle or nozzle are pervasive mid-19th-century mechanics — the Blake patent in the record (US123,765, Feb. 20, 1872) uses a pin H with deliberate play between projections v/w as a motion-limiting/regulating device; US181,929 (post-dating, but demonstrative) has pins i t entering notches to act "as stops for the turning of the nozzle"; US127340A is titled to the same class of swing basin cock, which necessarily must locate the nozzle's backward position. The series-of-holes-and-a-pin adjuster is the standard indexing expedient of the period (clock, lock, and gun work).

Rationale (KSR) — (A) predictable combination; and, independently, claim 6 is a classic mere aggregation: the openings and the pin each perform their own function (indexing) and produce no result beyond the sum of their separate effects. The patent's assertion that the adjuster lets the nozzle be set "to its right position when the valve is in connection with its seat" is precisely the expected result of putting an indexing stop on an indexed rotary member — nothing more.

Honest limitation. I did not locate and verify a pre-1873 reference disclosing the pin-in-a-series-of-vertical-openings adjuster specifically. The strongest pre-1873 pin/stop disclosure I verified is US123,765 (Blake, pin-and-projection limiter) plus the general indexing practice of the era. If a printed 1873 references-cited list or a full 19th-century search exists, that is where the missing claim 6 reference would likely be found. I will not assert a specific anticipation I have not seen.

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4. Recommended § 103 combinations

Cross-cutting motivation statement (for the record): all references are in the same field of endeavor — faucets, basin cocks, compression cocks, valves — so the "analogous art" predicate is satisfied without argument. The 1872–75 vintage of US127340A, US169952A and US124,840 demonstrates a crowded art with a recognized, unsolved problem (shutting a swinging basin faucet off at both nozzle positions while keeping it open when forward), i.e., a classic KSR design incentive and a small, finite solution space.

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5. What would not be obvious, and where the patent can defend itself

1. The two-opposed-valve / single-screw-stem kinematics (claim 3 within the claim 1+3 whole). A single screw-stem carrying opposed valves, rotated by the nozzle's swing through the indexed ball joint, so that one valve seats at each swing extreme, is more than the sum of the parts and produces a new mode of operation. This is the strongest nonobviousness position, and it would be the argument to advance.
2. The annulus-as-alignment-solution in claim 5 — arguably an unrecognized-advantage theory (the side-opening stays ported at every swing angle). Weak, because the requirement is self-evident from the function.
3. Avoidable error to note: the claims use "substantially in the manner and for the purpose set forth" / "substantially as described," which in this era was construed narrowly — the claims are limited to the described structure. That cuts both ways: it narrows the claims, but because the prior art (Maclaren for claims 1/2/4/5; the swing-cock class for claims 3/6) shows that same structure, narrow construction does not rescue them.

Secondary considerations: the record supplies none — no commercial-success, long-felt-need, failure-of-others, copying, or licensing evidence. The two-thirds assignment to McCambridge and Kennedy is a transfer of rights, not a recognition of inventiveness.

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6. Limitations and contradictions I must flag

6.1 Anachronism (repeated for emphasis). § 103 is the wrong statute for a February 4, 1873 grant; and during 1873–1890 the Cuno "flash of creative genius" gloss — since repudiated — would have made a challenger's burden heavier than a modern § 103 analysis suggests. My conclusions above are, if anything, more favorable to invalidity than the law actually in force during the patent's term.

6.2 The page's prior-art set is mostly unusable. Because 21 of the 25 "Similar Documents" post-date the grant, and because the record supplies no filing date, the analysable prior-art base is only US43125A, US59346A, US127340A (plus possibly US131556A) — supplemented by my independently verified US124,840. Any analysis that treats the Google Patents "Similar Documents" list as prior art wholesale would be wrong.

6.3 Unresolved conflict on US127340A — do not over-rely on it. The fetched Google Patents page lists US127340A, 1872-05-28, "Improvement in swing-compression basin-cocks." However, a contemporaneous Government Printing Office list of patents granted May 28, 1872 (Patents No. 127,136–127,401) records "127,340 Collar, (109,) Godfrey and Fuller, (reissue)" — a reissue of a collar, in a different classification, by different inventors, with no basin-cock title. I could not retrieve the body of US127340A to settle which is correct. I have therefore used US127340A only as a class-defining citation (evidence that the "swing-compression basin cock" category existed by May 1872), and I have not asserted any specific disclosure from it. If the Godfrey–Fuller identification is right, the title on the page is unreliable and combination A's base reference should be re-selected.

6.4 OCR corruption in the claim text. Claim 5 reads "annular space, u" where the specification says n; the specification itself interchanges E and E′ for the upper valve; the upper seat appears as both b′ and "Z1"/"b1." I have reconciled these against the specification but cannot verify the printed originals. Claim 5's exposure is therefore stated with lower confidence than the rest.

6.5 No verified pre-1873 reference for claim 6's specific adjuster. Combination D rests on analogy and aggregation doctrine, not on an identified anticipating structure. I have not fabricated one.

6.6 What I did not search. I did not search the Federal Cases reporter, 19th-century E.D. Pa. archives, or the printed annual Specifications and Drawings volumes for a fuller 1872 prior-art set (the GPO volume cited in §6.3 would be the right place to start). A proper § 103 search of the 1860s–72 faucet art would likely harden combinations B, C and D considerably.

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7. Bottom line

On the prior art actually available from this record, claims 1, 2, 4 and 6 are strongly vulnerable to a § 103 (or 1870-Act "want of invention") rejection, claim 5 is moderately vulnerable on reconstructed text, and claim 3 is the only claim with a genuinely arguable nonobviousness position — though even claim 3 likely fails under a KSR-style "predictable use of prior art elements according to their established functions" rationale, since the swing-cock class already located the shut-off positions at the nozzle's swing extremes and the ordinary compression faucet already provided the screw-stem-and-seat pair the patentee admits is conventional. If the patent were re-examined today on this record alone, the probable outcome is cancellation of claims 1, 2, 4 and 6 and rejection of claims 3 and 5 over US124,840 (Maclaren, 1872-03-19) in view of the swing-compression basin-cock art of 1872, with the caveat in §6.3 as to which reference that is.

Confidence: High on the legal framing and on the Maclaren disclosure (text verified). Moderate on claims 3 and 5. Low on the identity of US127340A and on any specific claim-6 reference.