US 875023

I'll search for this specific patent number and check for any litigation dockets.

Let me run more targeted searches to verify against the authoritative record and check for litigation.

Let me attempt to recover the exact claim text and confirm there is no litigation record.

Search disposition (what I actually ran, and what came back)

CAFC 2026 docket finding: I found no record of any 2026 Federal Circuit docket involving patent 875,023. I cannot positively certify a negative from general web search — CAFC dockets are indexed through PACER/CourtListener rather than general search, so absence of hits is suggestive but not conclusive. Independently, per the record below, the patent's anticipated expiration was 1924-12-31, so it is long expired and could not support an infringement appeal today. The more likely explanation for any "875023 docket" question is a numbering conflation — e.g., a modern 7- or 8-digit patent such as US 8,750,230, or the OSTI ID above. Per your strict rule, I have not auto-corrected the number and am treating "875023" literally as US 875,023.

US 875,023 — "Projectile"

The authoritative record is the granted specification itself (https://patents.google.com/patent/US875023/en), which I used as the controlling source.

Abstract

None exists in the official record. US 875,023 predates statutory abstracts (mandatory only from 1952). Google Patents' "Definitions" block is a machine-extracted fragment of the specification, not an abstract. A faithful derived summary from the specification:

The invention relates to capped armour-piercing projectiles, and its object is to improve penetration and range without weakening the shell. The inventors discovered that penetration is governed not by the time interval between the cap's blow and the shell tip's blow, but by the relative momentum of the two bodies. They accordingly use a cap of far greater weight than previously thought practicable (well beyond mere lubrication or lateral tip support), and give that heavy cap a frusto-conical or otherwise tapered form for at least the greater part of its length so that range is not sacrificed. The heavy tapered cap is especially advantageous on a shell with a long ogival point whose base-portion radius of curvature is 2.25–4 times caliber (preferably ~2.5), per US 721,487. The disclosure also extends, to a certain extent, to dummy/practice shells having the same contour, weight, centre of gravity, and mass distribution — optionally cast in one piece with the cap.

Plain-language overview of the independent claims

There are five claims, all independent (no dependent claims). Claim 1 is drawn to a projectile-with-cap per se; claims 2–4 progressively add "frusto-conical" cap form and/or the long-ogival-point geometry; claim 5 adds the armour-piercing character and the momentum-based functional statement.

1. Claim 1 — Projectile with a heavy cap. A projectile carrying a cap whose weight is not less than a stated minimum proportion of the weight of the uncapped projectile (the specification states the minimum as a formula C [≥] …, with C = cap weight and W = uncapped-shell weight, both in pounds). Point of novelty: the minimum weight threshold itself, above what the art considered practicable.
2. Claim 2 — Heavy cap + tapered shape. A shell with a cap of at least that same minimum weight and of frusto-conical form (the shape limitation added to preserve range).
3. Claim 3 — Long ogival point + heavy tapered cap. A shell whose point has a base-portion radius of curvature not less than 2.25 times its caliber, surmounted by a cap of at least the minimum weight and of frusto-conical form. (The specification adds that 2.25–4× caliber is the working range, "preferably 2.5 times.")
4. Claim 4 — Long ogival point + heavy cap. Same as Claim 3 but without the express frusto-conical limitation — a shell with a point of base radius ≥ 2.25 × caliber surmounted by a cap of at least the minimum weight.
5. Claim 5 — Armour-piercing projectile + heavy attached cap, functionally defined. A capped projectile combining an armour-piercing projectile and an attached cap on its point, the cap exceeding a stated weight proportion of W, "whereby the momentum of impact substantially in advance of the projectile itself may materially affect the resisting powers of the plate to the projectile" — expressly "in contradistinction to the heretofore known or assumed effect of lubrication." This is the claim that captures the inventors' momentum hypothesis as a functional limitation, and it is the one most likely to be attacked in any validity analysis (functional claiming + the specification's own admission that the theory is "hypotheses" only).

⚠️ Documented uncertainty (please read before quoting the claims)

The claim numerals are materially OCR-degraded in the authoritative source I retrieved. The specification text renders the minimum-weight expressions as fragments — e.g. "a cap of a weight 40o u 100" (claim 1), "a cap o a Weight not less … uncapped projectile" (claim 2, numeral dropped entirely), "a cap of a weight of not less than 490" (claim 4), and "the said cap exceeding the weight zml-50400" (claim 5). In the original these are stacked fractions with W as numerator, and the OCR mangled them.

I therefore decline to state the exact numeric threshold in claims 1, 2, 4 and 5. The specification's prose corroborates only that (a) a minimum C-relative-to-W formula was adopted, and (b) that minimum "could well be exceeded fifty percent in large shells." Any figure you publish should be taken from a clean facsimile of the printed patent (USPTO PatentCenter PDF or the Google Patents PDF) rather than from the HTML text. Everything else above — parties, dates, geometry, and the qualitative scope of each claim — is corroborated and I state it with confidence.

Three cautions for downstream use

• The doctrine here is 120 years stale and was self-described as hypothesis. The specification says the theories are "hypotheses" and that "ample and repeated tests have demonstrated the superior penetration and greater range." Do not treat the momentum rationale as settled technical fact; it is the inventors' characterisation.
• Term is long over. Expiration 1924-12-31 means no live rights, no possible CAFC 2026 appeal on this number, and sole relevance today is as §102 prior art.
• Do not merge this record with OSTI ID 875023 or with any 7-digit US number. Those are distinct identifiers for distinct subject matter.

I'll run the searches as instructed, treating "875023" literally and looking specifically at litigation databases.

The general searches surfaced only unrelated patents (e.g., "the '023 patent" shorthand for US 7,979,023, and hip-implant cases). Let me search litigation-specific databases with the literal number.

Let me try the litigation portals directly and with comma-formatted numbering.

Search Results: Litigation Involving US Patent 875,023

No litigation is known for US Patent 875,023.

What I searched

I ran searches aimed specifically at litigation databases and dockets (Unified Patents portal, CourtListener, Justia federal dockets, PACER-adjacent sources, PTAB filings), querying the literal identifiers 875023, US875023, and 875,023. I did not auto-correct or "expand" the number.

What the searches returned

Every litigation hit was for a different patent that is commonly abbreviated using the "'023 patent" shorthand — not US 875,023. Specifically:

• Stryker Corp. v. Intermedics Orthopedics, Inc. (hip prosthesis) — shorthand for US 5,314,023 (Fed. Cir. 96 F.3d 1409; E.D.N.Y. No. CV-90-3006). Unrelated.
• Sonos v. Linkplay / IPR2025-00509 — shorthand for US 10,853,023 (wireless audio). Unrelated.
• Alcon / LenSx declaratory-judgment pleadings — shorthand for a cataract-surgery patent ('023). Unrelated.
• Genelabs / Affymetrix small-entity maintenance-fee dispute (D. Del.) — shorthand for a different '023 patent. Unrelated.
• Kenall v. Genlyte Thomas — unrelated ('254 patent).
• Ser. No. 875,023 (Loebner, portable floor, US 3,611,655) — this is an application serial number, not US Patent 875,023, and involves no patent litigation.

I found zero records tying US Patent 875,023 to any case in Unified Patents' litigation caselist, CourtListener, Justia, or PTAB records.

Why this is expected (context, not a substitute for the search)

US 875,023 ("Projectile") is a 1907 patent:

The patent's term ended over a century ago, so it could not support an infringement suit today. Its citation history in the record (US 748,827; US 721,487) is prior-art/related-patent family material, and the only forward citation listed on the Google Patents page is US 6,834,592 B2 (Armaturen-Gesellschaft, 2004) — also not litigation.

Caveats and confidence

• Confidence: high that no modern (electronically indexed) litigation exists. Any litigation would have had to occur before ~1924, which predates PACER, Unified Patents, and most searchable federal docket coverage. I cannot rule out a century-old case that exists only in paper archives and was never digitized; such records would not appear in the sources I was instructed to search.
• I did not find (and cannot produce) the requested fields — plaintiff, defendant, jurisdiction, case number, filing date, outcome — because no case matches this patent number. I am not inventing them.
• Per the strict rule, I have kept 875023/US 875,023 literal and have not substituted the similarly-numbered patents above, which the searches surfaced in error.

I'll verify the structured data with targeted searches before reporting.

PTAB / AIA Trial Proceedings on US Patent 875,023

Proceedings overview

Total AIA trial proceedings on file: 0 (zero). Canonical source — the structured "PTAB proceedings on file" block from the USPTO Open Data Portal ingest — returns no IPR, PGR, or CBM proceedings for US 875,023; the breakdown by status is therefore 0 active / 0 claims invalidated / 0 claims sustained / 0 settled / 0 institution denials. Bottom line for a defendant: there is no PTAB record to work with — but you almost certainly do not need one. The patent's term ended on 1924-12-31, roughly 88 years before the first AIA petition was ever filed, so the correct defensive posture is not "the patent has survived IPRs and is hardened," but rather "there is nothing left to assert." If a demand letter cites US 875,023 as a live right, the letter is facially defective and the right response is a statute-of-limitations / expired-term rejoinder, not an IPR budget.

No proceedings to report

There is no {PROCEEDING_NUMBER} to list. Listing one would require fabrication, which I will not do. Every field the task asks for — petitioner, patent owner, institution decision, FWD claim-level disposition, panel, settlement, CAFC appeal — is empty because the proceeding does not exist.

What I searched (2026-09-30)

Every hit for the string "023"/"201" in a PTAB context resolved to a different patent. This mirrors the shorthand-collision problem flagged in the litigation section above, where "'023 patent" resolved to US 5,314,023 (Stryker hip stem), US 10,853,023 (Sonos), etc.

Why there is no PTAB activity (statutory + practical)

I want to be precise here rather than rely on the "it's expired" shortcut alone, because expiration is not a statutory bar to IPR — the Board has instituted trials on expired patents (the patent owner simply loses the ability to amend claims into enforceability, which removes much of the incentive to defend). The actual reasons are:

1. PGR is unavailable by date. Post-Grant Review under 35 U.S.C. §§ 321–329 applies only to patents with an effective filing date on or after 2013-03-16. US 875,023 has an effective filing date of 1905-11-02.
2. CBM is unavailable by subject matter and by date. Covered Business Method review under AIA § 18(d)(1) required a patent claiming a "financial product or service." US 875,023 claims an armor-piercing projectile cap (claims 1–5). It also sits far outside the § 18(a)(1) eight-year CBM window (petitions accepted only 2012-09-16 through 2020-09-16).
3. IPR is technically available in the abstract but economically inert. IPR under §§ 311–319 has no patent-age limit. What kills it is that the patent expired 1924-12-31 — over a century ago. No one can infringe an expired patent, so no accused infringer ever has the § 315 economic incentive to pay the ~$40k+ cost of a petition, and no patent owner has standing to assert it. There is also no § 315(b) one-year clock to trigger, because there is no co-pending infringement action.
4. The forward-citation record confirms the dormancy. The only forward citation on the Google Patents page is US 6,834,592 B2 (Armaturen-Gesellschaft, 2004) — a shell-construction reference, not an assertion event, and itself not subject to any PTAB challenge in the retrieved record.

One historical item worth knowing (not a PTAB proceeding)

My search surfaced a 1915 Third Circuit case that names US 875,023, which refines — rather than contradicts — the litigation summary's "no litigation known" finding. I want to flag the distinction explicitly because it is easy to misread:

• Firth-Sterling Steel Co. v. Bethlehem Steel Co., 224 F. 943 (3d Cir. 1915) — the patent in suit was US 945,492 (Davis), not 875,023. The court's prior-art analysis expressly lists "United States letters patent No. 875, 023 to Wheeler and McKenna, 1907" alongside Johnson (US 541,280), Hadfield (US 720,242), Gleinich (US 841,861), Staunton (GB 8,764/1900) and Motteram (GB 751/1904), holding that "in 1908, pointed projectiles were old, and the function of contour was known in the art." See https://www.courtlistener.com/opinion/[8808862](/patent/8808862)/firth-sterling-steel-co-v-bethlehem-steel-co/ (full text also at https://storage.courtlistener.com/harvard_pdf/[8811947](/patent/8811947).pdf).
• Significance: US 875,023 functioned as invalidating prior art against a later Firth-Sterling-family patent, not as an asserted patent. The court's reasoning leaned on the Wheeler and McKenna disclosure to show that sharp-pointed, contour-capped projectiles were known. This is the opposite of a defensive anchor — it means 875,023's own disclosure is a public-domain teaching, which further undercuts any theory that its claims retain residual value.

This is a century-old Article III case, not an AIA trial. It belongs in the litigation section, and I flag it here only because the search for PTAB activity is what surfaced it.

Strategic summary

Claim status: every claim is UNTESTED at the PTAB, and every claim is UNENFORCEABLE by lapse. Claims 1–5 (the cap-weight-percentage claims, the 2.25×-caliber radius claim, and the capped-armor-piercing-projectile claim) have never been construed by the Board, never been canceled, and never been confirmed. There is no narrowing certificate, no adverse-judgment certificate, and no ex parte reexamination certificate of record. The patent's legal life ran from 1907-12-31 to the anticipated expiration of 1924-12-31, and under 35 U.S.C. § 154 the term is not extendable now. So the practical answer to "which claims survive?" is: none that can be asserted. I am not going to dress an empty record up as a "hardened patent."

Estoppel landscape: there is none to navigate. Section 315(e)(2) estoppel attaches only to a petitioner that obtained a final written decision. No petitioner ever did. That means there is no estoppel barring anyone — but there is also no FRAND-ly available prior art "still in play," because the claimed subject matter has been publicly disclosed since 1907 and expressly relied on by the Third Circuit in 1915 as showing the state of the art. For completeness on availability: IPR, PGR and CBM cannot reach this patent's pre-1900s effective filing priority in any meaningful way, so the choice is not "which ground remains" but "why would you file."

Pattern signals: all three are negative. (1) No repeat petitioner — there is no petitioner at all, so no serial-IPR pattern. (2) No PTAB appeals — the patent owner (Firth Sterling Steel Co., and its successors) never pursued a Board appeal, because no Board proceeding ever existed; the only appellate history touching this patent is the 1915 Third Circuit prior-art citation above. (3) No defensive aggregator — Unified Patents and similar entities did not exist in a form that could reach this patent, and the retrieved caselist shows no Unified Patents involvement with 875,023. The absence of PTAB activity is emphatically not the usual "this patent was never commercially significant" signal; it is the far stronger signal that the patent is a century past its term.

Recommended next steps

If you are a defendant and have received a demand citing US 875,023:

1. Do not file an IPR. There is no live claim to invalidate, and an IPR on a patent that expired on 1924-12-31 cannot produce a useful estoppel or a damages defense that the expiration date does not already give you. Do not let a demand letter push you into a five-figure PTAB spend on a 1907 ordnance patent.
2. Run the dates first. Confirm the expiration against the Google Patents record (filing 1905-11-02, grant 1907-12-31, anticipated expiration 1924-12-31) and against the patent's face. Under § 154 and pre-1995 term rules (17 years from grant), the term is long since run. A demand citing this patent as enforceable is a strong indicator of a bad-faith or automated letter mill.
3. Cite the prior-art use against the citing party if they pivot. If the same party asserts a later projectile/kinetic-energy-penetrator patent and relies on 875,023's lineage, the 1915 Third Circuit finding that "in 1908, pointed projectiles were old, and the function of contour was known in the art" — grounded in part on the 875,023 disclosure — is a directly usable obviousness datapoint.

If you were hoping for a defensive shield from an IPR FWD: there is none, and I will not manufacture one. Link-verified references for anything I did find:

• PTAB E2E (portal) — https://ptacts.uspto.gov/ptacts/ (search "875023"; zero proceedings returned)
• PTAB Decisions — https://www.uspto.gov/patents/ptab
• Firth-Sterling Steel Co. v. Bethlehem Steel Co., 224 F. 943 (3d Cir. 1915) — https://www.courtlistener.com/opinion/8808862/firth-sterling-steel-co-v-bethlehem-steel-co/ (875,023 cited as prior art at the court's prior-art discussion)

Plain answer to the task as posed: no PTAB activity exists on US 875,023. The absence here is not a "well-asserted patents eventually attract IPRs" signal — it is the terminal signal that the right expired before the AIA existed.

I'll research the assignment record and the corporate history of the original assignee before writing this section.

Good leads on the inventors' employer. Let me pin down the assignee's corporate history and the coverage limits of the assignment databases.

Ownership chain — US Patent 875,023 ("Projectile," Wheeler & McKenna, granted 1907‑12‑31)

Headline finding, stated up front: there is one assignment in this chain — the original, face‑of‑patent assignment from the two inventors to Firth Sterling Steel Co. No post‑issuance assignment, security agreement, merger, license, release, correction, or change‑of‑name recording is indexed for this patent. The term expired 1924‑12‑31, so the entire modern ownership‑tracking apparatus (reel/frame correspondents, NPE chains, pre‑litigation transfers) has no era in which to operate on this asset.

Inventors

Unusual patterns — flagged:

1. Both inventors left the Pittsburgh/Braddock works district, not the assignee. By the 1909 filings (US 950,586, filed 1909‑07‑03; US 963,489, filed 1909‑03‑01), both inventors give their residence as Washington, D.C. (US950586; US963489). Charles Van Cise Wheeler's genealogy likewise records his residence as "Washington, D." after his 1899 marriage (Wheeler genealogy).
2. This is not the classic "all inventors depart within 12 months → portfolio fire‑sale" tell. The move took ~3–4 years, was geographic/professional (consistent with ordnance work in the capital, where the Navy's armour‑and‑projectile test establishment sat), and the inventors kept inventing under the same assignee for at least four more years. The assignment relationship was never severed. No fire‑sale inference is supportable.
3. Inventor–assignee concentration is total. Every Wheeler/McKenna projectile patent I can see in this era is assigned to Firth Sterling. There is no inventor‑held (unassigned) counterpart in the family, which is what one normally looks for before a later individual‑to‑shell transfer.

Original assignee

Firth Sterling Steel Company, a corporation of Pennsylvania (Braddock / McKeesport / Pittsburgh, PA). Google Patents still lists Firth Sterling Steel Co. as the current assignee, i.e. no later assignment has displaced it in the indexed record (US875023).

• Primary line of business: crucible and alloy specialty steel, and specifically armour‑piercing projectiles and projectile steels — the company was the American arm of the Firth (Sheffield) interest, formed when Thomas Firth & Sons' people joined the Pittsburgh Sterling Steel Co. The McKenna family history notes "Firth Sterling was owned by Englishmen and … Lewis J. Firth had come to America to be general manager, [while] Bernard A. Firth was the managing director of Thomas Firth & Sons, Ltd." It later became a US pioneer of chromium stainless steel (Owen Parmiter of Firth‑Sterling Steel Co., McKeesport, PA, 1924 paper on Brearley cutlery steel — ASM/SAE stainless history).
• Did they ship a product embodying the claims? Yes. This is not a paper patent. The specification records that the cap tests were "carried out under the auspices of the United States Government," and the companion patents describe a "six inch armor piercing capped projectile embodying the present improvement." Firth Sterling was a Navy projectile supplier; the claims read on manufactured capped AP shell.
• Current status: not operating as an independent entity. Per a history of electro‑slag refining, Vasco (Latrobe, PA) was "subsequently taken over by Teledyne, who finally closed down the Firth Sterling operations," and a 1999 federal trade hearing lists "Firth Sterling" among the specialty‑metals operations "shut down" within Allegheny Teledyne (electro‑slag refining history; TDRC hearing transcript, 1999‑10‑29). The successor chain runs Teledyne → Allegheny Teledyne Corp. (Allegheny Ludlum and Teledyne became wholly owned subsidiaries of Allegheny Teledyne on 1996‑08‑15, per ATI's 1997 annual report) → later Allegheny Technologies Incorporated. Confidence on the intermediate Teledyne acquisition date is medium; treat the successor names as verified and the timing as unverified.
• Materiality point: none of these corporate events transferred this patent. It expired in 1924; it could not have been an asset in a 1960s, 1996, or 1999 transaction.

Assignment timeline

Recorded assignment 1 — the original assignment

• Executed: on or before 1905‑11‑02 (application filing date; the patent prints "ASSIGNORS TO FIRTH STERLING STEEL COMPANY, A CORPORATION OF PENNSYLVANIA") / recorded at issue, 1907‑12‑31
  • Conveyance: Assignment (inventors → assignee)
  • Assignor: Charles Van Cise Wheeler and Alexander George McKenna, jointly
  • Assignee: Firth Sterling Steel Company, a corporation of Pennsylvania
  • Correspondent: not indexed / not determinable — see caveat below. I am not supplying a name here. Pre‑1980 recordings are not in the electronic Assignment Center index, so no correspondent, reel, or frame can be read from it for this patent, and I will not invent one.
  • Context: standard inventor‑to‑employer assignment at filing (employment‑origin rights transfer), not an acquisition.

No further records

There are no post‑issuance assignment records for US 875,023. Specifically, nothing is indexed for:

• any Assignment after 1907‑12‑31;
• any Security Agreement (never securitized against this patent in any indexed record);
• any Merger (the Firth Sterling → Teledyne → Allegheny Teledyne → ATI lineage was effected at the corporate level; patents of an expired term were not separately conveyed in any record I can see);
• any Change of Name, License, Release, or Correction.

The Google Patents legal‑events record for US 875,023 shows only: 1905‑11‑02 application filed / priority; 1907‑12‑31 application granted and published; 1924‑12‑31 anticipated expiration (17 years from grant). No assignment or reel/frame entries of any kind appear. This corroborates the earlier litigation finding in this analysis (zero cases; the only forward citation is US 6,834,592 B2, Armaturen‑Gesellschaft, 2004 — a citation, not an assignment).

Verification links: USPTO Assignment Center and USPTO Patent Assignment Search — search 875023. Caveat on method, stated plainly: the tools available to me returned search‑engine results only; I could not render the Assignment Center's own result table. My negative finding therefore rests on (i) the absence of any assignment event in the indexed legal‑events record, (ii) the face of the patent, and (iii) the database's ~1980‑to‑present coverage window, which structurally excludes this patent's entire enforceable life. A pre‑1980 posting does exist in USPTO's paper/microfilm assignment records; I cannot read it, and its contents are unknown to me — any reel/frame in this chain is not reported, not estimated.

Timeline diagram

timeline
    title Ownership of US 875023
    1905 : Filed by Wheeler and McKenna
         : Assigned to Firth Sterling Steel Co
    1907 : Patent granted
    1909 : Inventors refile from Washington DC
    1924 : Patent term expires
    1968 : Firth Sterling ops absorbed by Teledyne
    1996 : Teledyne merges with Allegheny Ludlum

Lines from 1968 onward are corporate‑successor context, not recorded assignments to this patent.

NPE / troll‑pattern signals

Method note: several of these signals are not merely absent but structurally inapposite — the patent expired 84 years before RPX, Unified Patents, and the modern NPE market existed. I mark them accordingly rather than falsely scoring them "present."

Verdict

Insufficient data — with a specific, bounded negative finding: only the original assignment exists.

The chain consists of exactly one link: the inventors' assignment of 1905‑11‑02 to Firth Sterling Steel Company, recorded at issue on 1907‑12‑31, and the Google Patents legal‑events record shows no assignment, security interest, merger, or licence entry thereafter, with anticipated expiration on 1924‑12‑31. No shell entity, no listed asserter, no repeat correspondent (that field is unpopulated because no reel/frame is indexed), no cascading transfers, and no pre‑litigation transfer can be identified. NPE analysis is structurally inapplicable to a 1907 patent whose term lapsed in 1924; the honest classification is "no post‑issuance records," not "NPE" and not "defensive aggregator."

One caveat I want on the record, per the operating rules: I could not read the USPTO Assignment Center's own result table with the tools available, and the electronic index begins around 1980 — i.e. it excludes this patent's entire enforceable life. Pre‑1980 paper/microfilm recordings for US 875,023, if any, are unknown to me. If you need certainty on the Firth Sterling → Teledyne corporate conveyance of Firth Sterling's patent assets, that requires the paper assignment abstracts or the Teledyne/Allegheny Teledyne merger agreements, not the assignment database. Verify at https://assignmentcenter.uspto.gov/ and https://assignment.uspto.gov/patent/index.html.

Contradiction check against earlier sections: none. This section's expiration date (1924‑12‑31), assignee (Firth Sterling Steel Co.), inventors, and zero‑litigation finding are all consistent with the litigation section already generated.

I'll verify the citation records for this patent before building the prior-art table. Let me pull the two references named in the specification and cross-check the citation/forward-citation records.

The searches surfaced two important leads: a later same-inventor family patent that cites US 875,023, and a Court of Claims decision about a "dimensional formula" shell patent. Let me pin those down, plus the US 748,827 reference.

Prior-Art Analysis — US Patent 875,023 ("Projectile")

Inventor(s): Charles Van Cise Wheeler; Alexander George McKenna
Assignee: Firth Sterling Steel Co. (Pennsylvania)
Filed: 1905-11-02 (Ser. No. 285,601) • Granted: 1907-12-31 • Expired: 1924-12-31
Spec source of record: https://patents.google.com/patent/[US875023](/patent/US875023)/en

0. Method and a necessary caveat on the source record

I searched the literal identifiers 875023 / US 875,023 and did not substitute any similarly-numbered patent. Both of the following matter for interpreting the results:

1. The fetched US 875,023 record contains no machine-readable "Patent Citations" table. The page supplies "Prior art keywords," a "Similar Documents" list, and a "Cited By" list — but no backward-citation table. Therefore the only true citations of record for US 875,023 that I can point to are the two US patents named inside its own specification text.
2. "Similar Documents" is algorithmic, not a citation list. Google Patents generates it by classification/text similarity. Treating those entries as "citations of 875023" would be a category error — I flag them separately in §3 and mark them unverified.

Two verification gaps are explicit up front: my search budget was exhausted before I could pull the filing dates of US 748,827 and US 721,487, and before I could read the disclosures of the pre-1905 "similar documents." I will not invent those facts.

1. References cited in US 875,023 (backward citations of record)

Bottom line for §1: zero anticipatory references. Both are the inventors' own earlier patents, incorporated for two sub-combinations (attachment; point geometry) that the 1905 claims deliberately do not claim as such. That is consistent with the specification's own framing that the novelty lies in the heavy, tapered cap weight relative to the uncapped shell.

2. Forward citations and later same-family patents citing US 875,023

⚠️ Note for the family record: US 950,586 and US 963,489 both cite US 875,023 in their specifications, yet the Google Patents "Cited By" list for US 875,023 shows only US 6,834,592. The citation count of record is therefore incomplete on the fetched page; the substantive citations are recoverable only from the family patents' text.

3. "Similar Documents" on the US 875,023 page (algorithmically related — not citations)

I list these only because they are the other pre-1905 documents in the field, and they are the plausible § 102 candidates. I did not verify their disclosures, so I assert no anticipation. Date alone decides availability:

Pre-filing (potentially available under § 102(a)/(b) if their disclosures reach the claim elements):

Post-filing (cannot be § 102 art to a 1905-11-02 filing, absent unverified earlier priority): US 806,820 (1905-12-12, armor-piercing — grant date after the filing date; its filing date is unverified and would need checking before it could be used at all), US 816,577 (1906), US 893,963 (1908), US 968,012 (1910, "Cap for armor-piercing projectiles"), US 1,072,7xx/1,073,349 (1913), US 1,083,161/1,089,161 (1914), US 1,102,758 (1914), US 1,149,602 (1915), US 1,172,511 (1916, "Cap for armor-piercing projectiles"), US 1,276,082 (1918), US 1,302,822 (1919), US 1,312,762 (1919), US 1,892,158 (1932), US 3,213,792 (1965).

4. Prior art identified by a federal court in the related Firth Sterling litigation — a finding that updates the earlier litigation section

The earlier section concluded "No litigation is known for US Patent 875,023." That remains true in the narrow sense (no case in which 875,023 was the patent in suit), but it is incomplete: US 875,023 appears by number, as cited prior art, in the reported opinions of the Firth Sterling / Bethlehem Steel projectile litigation.

• Bethlehem Steel Co. v. Firth Sterling Steel Co. (opinion discussing the Davis combination patent): the court lists, among the old art showing that "pointed projectiles of various dimensions existed" before Gleinich's 1907 contour discovery — "United States letters patent No. 875,023 to Wheeler and McKenna, 1907," alongside US 541,280 to Johnson (1895), British No. 8,764 of 1900 to Staunton, British No. 751 of 1904 to Motteram, and US 720,242 to Hadfield (1903). The same opinion also cites earlier caps: British No. 1,872 of 1860 to Haddan and British No. 1,615 of 1863 to Clark, and notes US 841,861 to Gleinich (1907) for the 4.7–8.2-caliber radius range. https://www.courtlistener.com/opinion/[8811947](/patent/8811947)/bethlehem-steel-co-v-firth-sterling-steel-co/
• Firth-Sterling Steel Co. v. Bethlehem Steel Co., 199 F. 353 (E.D. Pa. 1912), Docket No. 431 — the companion/related action (patent in suit there: US 945,492, issued 1910-01-04; the "Phillips," "Wheeler and McKenna," and "Davis" designs are discussed as successive independent arrivals at the same idea). https://case-law.vlex.com/vid/firth-sterling-steel-co-895324145
• The appellate opinion is cited as 224 F. 937; I did not independently confirm the court or year, so treat "3d Cir. 1915" as probable, not verified.

Two consequences for this prior-art analysis:

1. US 875,023 was itself the prior art. This is the strongest available evidence that the heavy-cap/contour subject matter was old in the field by 1908–1915 — and it simultaneously confirms that claim 1's weight-ratio limitation was the patent's point of novelty, because the courts treated 875,023 as the "contour/pointed projectile" reference, not as a weight-ratio reference.
2. The court-identified references are better § 102 candidates than the "Similar Documents" list, because a federal court made findings about them. See the table below — but note the same court found that none of them disclosed the precise dimensional combination.

⚠️ Unverified lead I am flagging rather than asserting: a Court of Claims volume discussing a patent whose claim 3 rests on "a new dimensional formula for a shell" and "precise mathematical relationships and proportions" (with an accused shell having a 10.73-caliber ogive). That theme matches claims 1–5's structure, but I could not tie that case to US 875,023, and the described claim language does not match US 875,023's claim 3 verbatim. Do not treat it as litigation over this patent without confirming the case name and patent number.

5. Claim-by-claim § 102 mapping (claims as OCR'd from the record)

The claims as fetched are partly garbled. Reproduced with the corruption left visible:

• Claim 1 — "A projectile having a cap of a weight 40o u 100 (W being the weight of the uncapped projectile and the weights being expressed in pounds.)" → a pure cap-weight-relative-to-uncapped-projectile claim.
• Claim 2 — shell + cap of a weight "not less than" the same formula, "and of frusto-conical form."
• Claim 3 — point whose base-portion radius of curvature is "not less than 2.25 times its caliber," surmounted by a cap of the stated minimum weight "and of frusto-conical form."
• Claim 4 — same as claim 3, restated with the weight formula ("a cap of a weight of not less than 490. …").
• Claim 5 — a capped armor-piercing projectile with an attached cap "exceeding the weight zml-50400 where W is the weight of the uncapped projectile, whereby the momentum of impact substantially in advance of the projectile itself may materially affect the resisting powers of the plate … in contradistinction to the heretofore known or assumed effect of lubrication."

⚠️ Claim-numbering integrity flag: the numeric coefficient in the claim formulas is unreadable in the fetched text (apparent fragments "400"/"100" in claims 1–2; "490." and "zml-50400" in claims 4–5), and the description's parallel formula ("We adopted as a minimum formula …") is likewise dropped by the OCR. I will not guess the formula. Before any validity opinion, the numerical limits must be read off the printed patent (or the USPTO/Espacenet PDF).

Mapping:

Overall § 102 conclusion: on the assembled record, no reference anticipates any of claims 1–5, and claims 1, 2 and 5 look strongest (their entire novelty is the cap-to-shell weight ratio, for which no anticipatory disclosure was found). Claims 3 and 4 are the ones most exposed — not to anticipation, but to § 103 attack, because US 721,487 (the inventors' own patent) supplies the radius element and the pre-1905 contour-cap art (Hadfield, Haddan, Clark, Motteram, Staunton; all needing content verification) supplies tapered-cap disclosures once the weight ratio is recharacterized as a matter of degree. For an 1905-era filing this analysis would be run under the pre-1952 statute, but I have framed it in the § 102(a)/(b) terms you asked for, since the availability question is the same: does the reference predate the applicant's invention/filing?

6. What I could not verify (stated plainly)

1. Filing dates of US 748,827 and US 721,487 — only their grant dates are established (Jan. 5, 1904 and "March 24, 1903" per the specification / "February 24, 1903" per the family patents). The two-date conflict on 721,487 is an unresolved discrepancy in the record.
2. The actual disclosures of the pre-1905 "similar documents" (US 371,461; 388,496; 569,143; 623,707; 634,383; 753,504; 791,679) and of US 806,820's filing date.
3. The claim formulas (OCR-corrupted).
4. Whether the Court of Claims "dimensional formula" decision concerns US 875,023 — flagged as an unverified lead.
5. The court/year for 224 F. 937 — probable but unconfirmed.

Confidence: high that the two specification-named patents are the complete set of backward citations available on the fetched record and that neither anticipates; high that US 6,834,592 B2 is a forward citation only; high on the court-identified prior-art list as reported; low on any assertion of anticipation by the court-identified or "similar document" references, because their disclosures were not read.

I'll ground the obviousness analysis in the actual reference documents before combining them, since a §103 motivation must be anchored in what each reference discloses.

Several of these returns are directly material — including one that contradicts a prior section. Let me pin them down.

Two flags before the analysis

1. A contradiction with the earlier "Litigation summary." That section stated "No litigation is known for US Patent 875,023" and that no case ties the patent to any docket. Today's searches surfaced a case record that does: Bethlehem Steel Co. v. Firth Sterling Steel Co. (CourtListener opinion ID 8811947, reported in Fed. Rep. vol. 224, Sept. 1915, star pages *944–945; https://www.courtlistener.com/opinion/8811947/bethlehem-steel-co-v-firth-sterling-steel-co/). Its prior-art recital expressly lists "United States letters patent No. 720,242 to Hadfield, 1903; and United States letters patent No. 875, 023 to Wheeler and McKenna, 1907." Note the posture: 875,023 is cited as prior art against Cleland Davis's patent, not as the patent in suit — and Firth Sterling Steel Co. (875,023's assignee) was the defendant. So the earlier "no litigation" statement should be narrowed to: no case asserting 875,023, and no 2026 CAFC docket — the patent nonetheless appears in a litigated prior-art record. I did not locate a citation for the Court of Claims volume snippet that discusses "invention" in a shell "combined in precise mathematical relationships and proportions"; I flag it as an unverified lead, not a finding.

2. Date inconsistency. Your operating note says today is 2026-09-30; the task block says April 26, 2026. I've used neither to date anything material here.

1. Framework and two hard constraints

Legal frame. Section 103 was enacted in 1952; this patent issued in 1907 and expired 1924. The analysis below is therefore retrospective/hypothetical. Under the law of its own day the test was "invention" (a stricter, subjective standard later crystallized in Cuno Eng'g), not Graham/KSR. I apply modern §103 as you asked, using the Graham v. John Deere factors, and I note that the 1915 Bethlehem Steel opinion essentially ran the modern analysis avant la lettre when it held that the difference between competing capped projectiles "is largely a difference in mechanics and proportions" and that transposing a cap from blunt to sharp-pointed projectiles "would not call for invention. It would require only the skill of a mechanic."

Constraint A — the claim numerals are unusable. As established earlier, the weight-threshold expressions in claims 1, 2, 4 and 5 are OCR-garbled ("a cap of a weight 40o u 100"; "not less than 490"; "exceeding the weight zml-50400"). An obviousness analysis of a numerical-range limitation cannot be completed from the text I have. Everything below about the weight element is therefore conditional.

Constraint B — I have titles and dates, not disclosures, for most of the "Similar Documents" list. The page's prior-art section gives US 791,679, 623,707, 634,383, 371,461, 569,143, 388,496 and 753,504 as titles and dates only. The single most likely capping reference among them (US 569,143, "Armor-piercing projectile," 1896) is unverified as to content. I will not assert what it teaches. Where I name a reference as disclosing a cap, I am relying on text I actually retrieved.

2. The prior-art universe, gated by the critical date (1905-11-02)

Two of the page's post-1905 items deserve a caveat rather than dismissal: US 806,820 (published 1905-12-12) and US 893,963 (1908) could qualify as §102(e)-type art if their filing dates precede 1905-11-02. The page does not give filing dates, so I cannot resolve them. That is an open item, not a closed one.

The most important evidentiary find: the 1898 literature establishes that all three theories recited in the 875,023 specification were already in print. The RAI Minutes (https://upload.wikimedia.org/wikipedia/commons/8/85/Minutes_of_proceedings_of_the_Royal_Artillery_Institution_%28IA_minutesofprocee251898grea%29.pdf) record that fracture of the point "can in a great measure be prevented by a cap... whether the cap is hard and shattered or soft and crushed," with the footnote "It has been held that the cap spreading acts as a sort of lubricant," and the proceedings elsewhere develop the mechanism 875,023 claims as its discovery: "the mass of mild steel surrounding the point of the shell... might by its inertia oppose a powerful resistance to this sudden change of form, and so support the shell" (https://upload.wikimedia.org/wikipedia/commons/e/e9/Proceedings_%28IA_proceedings20roya%29.pdf).

3. Claim-by-claim obviousness

Claim 1 — projectile + cap at/above a minimum weight fraction of W

Elements: (a) projectile; (b) cap; (c) weight ratio.

(a)+(b) are saturated prior art (US 569,143, 803,031, 720,242; Johnson; Staunton). The claim rises or falls on (c). Proposed ground: §103 over US 803,031 (or US 720,242) in view of the pre-1905 cap-inertia literature. Motivation: if cap function is understood to derive from the mass/inertia of the metal about the point rather than lubrication, then cap mass is a result-effective variable and increasing it is an obvious design expedient (KSR: "a finite number of identified, predictable solutions"). Weakness: I have found no pre-1905 reference that expresses cap weight as a proportion of uncapped projectile weight. On this record the ratio element is not shown to be taught or suggested, and a continuous parameter is a poorer fit for KSR's "finite number of identified options" rationale than a discrete design choice. Assessment: the weakest claim to invalidate — and un-analyzable until the numeral is recovered.

Claim 2 — minimum cap weight and frusto-conical form

Adds shape. Proposed ground: the claim 1 combination + US 803,031's express statement that cap exterior shape "is immaterial, as it may be of any desired shape," + the art's uniform recognition that a tapered/ogival forebody reduces air resistance. The contemporaneous literature says outright that "Nearly every nation has now adopted, or is adopting, a long ogival cap of large radius of curvature, on account of the greatly increased range thereby obtained" (Naval Ordnance, Projectiles §). A frusto-conical form is the minimal transitional surface between an ogival point and a cylindrical body — KSR's "predictable use of prior art elements according to their established functions." Assessment: vulnerable, contingent entirely on whether a heavy-cap teaching is located.

Claim 3 — point base radius ≥ 2.25× caliber + heavy frusto-conical cap

The point geometry is the inventors' own US 721,487, cited on the face of the specification. The applicant has thereby stipulated the content of the prior art as to that element. Proposed ground: §103 over US 721,487 in view of US 803,031 (or US 720,242). Motivation is unusually clean: US 721,487 was itself directed to the range/penetration problem; US 803,031 teaches an armor-piercing projectile with a soft-metal cap and leaves exterior shape to the designer; and the 1898 literature supplies the reason to increase cap mass. Assessment: the strongest obviousness case on the page.

Claim 4 — same as claim 3 without the frusto-conical limitation

Note the drafting anomaly: claims 3 and 4 are both independent, and claim 4 is broader than claim 3. A broader claim cannot be non-obvious if the narrower one is obvious. Claim 4 is therefore obvious a fortiori to the extent claim 3 is. This is a structural (not evidentiary) conclusion and is the most robust statement I can make.

Claim 5 — armor-piercing projectile + attached heavy cap, functionally recited

Two independent grounds:

• The "whereby" clause is likely non-limiting. MPEP § 2111.04: a whereby clause that merely states the result of the structure as claimed is not given patentable weight unless it recites a structural limitation or a condition essential to patentability. Here it recites a theory of operation ("whereby the momentum of impact substantially in advance of the projectile itself may materially affect the resisting powers of the plate"), plus a disclaimer of the lubrication theory. Strip the clause and claim 5 is an armor-piercing projectile with an attached heavy cap — old structure.
• Even if given weight, no new result is shown. The Royal Society discussion quoted above discloses the inertia-of-cap-metal mechanism verbatim in substance. The 1915 Bethlehem Steel opinion likewise frames the whole art around "transmit[ting] the energy of impact of the mass of the shell and cap and depress[ing] the plate to the point of its elastic limit." And the specification's own concession that the theory is a "hypothesis" undercuts any argument that the result was unexpected.

Assessment: strong on structure; the functional clause adds little or nothing.

4. Consolidated motivation to combine

A KSR-compliant motivation exists on four independent legs:

1. Same field, same problem, same structure of the art. Every reference is armor-piercing-projectile art confronting face-hardened plate. No non-analogous-art dispute is available.
2. The prior art itself states the design trade-off. Hadfield's combination of a soft-metal cap with an overlying contour cap "obviously with the intention of obtaining in combination the advantages with respect to flight and penetration which he had been told each cap possessed" (Bethlehem Steel). The art had already articulated 875,023's own stated object ("improve range without weakening the shell") and the means of achieving it — cap for penetration, contour for flight.
3. The inventor's own prior patents are the missing pieces, and the spec joins them by cross-reference. US 721,487 supplies the long ogival point; US 748,827 supplies the means of cap attachment. Because these are the same inventors' own publications, there is no hindsight problem in attributing knowledge of them; the specification's own incorporation of both is effectively an admission.
4. A known mechanism supplied a reason to vary cap mass. By 1898 the art had identified cap-metal inertia (not lubrication) as the operative factor and had reasoned that "the greatest mass should be situated" about the point. That supplies a reason to increase cap mass and to prefer a tapered external form.

5. Where the patent might survive

• The weight threshold (claims 1, 2, 4, 5). The specification asserts unexpected results ("the surprising result being that the increase in the weight of the cap... improves instead of detracts from the penetration... notwithstanding that the vis viva of the hard shell itself is materially lessened") and records that heavy caps of cylindrical outline "somewhat reduc[ed] the distance or range." Under Graham factor three that is a genuine counterweight. But it is only a partial teaching away: the art discouraged solid heavy cylindrical caps for range reasons, not heavy caps as such, and the inventors' fix (taper the contour) was the standard aerodynamic measure of the day. The teaching-away doctrine requires the art to criticize, discredit or discourage the claimed solution, which this record does not do.
• The continuous-parameter problem. A numerical ratio sitting on a continuum is not the classic KSR "finite number of identified, predictable solutions" fact pattern. Absent a reference disclosing or suggesting the ratio, the weight element may stand. I cannot tell you whether that is so, because the numerals are corrupt.

6. What is needed to make this defensible

1. A clean facsimile of US 875,023's claims (USPTO PatentCenter or the Google Patents PDF) to recover the four lost numerals.
2. Full texts of US 569,143, US 371,461, US 791,679 and US 388,496 — the only pre-critical-date items whose disclosure I have not seen and the likeliest homes for a heavy-cap or contour-cap teaching.
3. Filing dates for US 806,820 and US 893,963 to settle §102(e)/§102(a)(2) availability.
4. The Johnson and Staunton (No. 8,764 of 1900) specifications, identified by name in Bethlehem Steel but not numbered there in retrievable form.
5. Confirmation of the Court of Claims snippet's patent number, since a contemporaneous decision on "a shell... combined in precise mathematical relationships and proportions... notwithstanding the existence of prior projectiles embodying the identical contour and shape" would bear directly on the weight-formula claims.