US 2486683

I'll verify the patent details against live sources before summarizing.

US 2,486,683 — Verification & Summary

Search note / scope: I searched for the exact identifier 2486683 / US2486683A. Results returned only the correct patent; no similarly-numbered patents were included. I did not have direct authenticated access to USPTO Patent Center, PACER, or the CAFC docket system — findings below are from web-indexed sources (Google Patents, the scanned original at patentimages.storage.googleapis.com, Justia). Please treat the litigation statement as "no evidence found" rather than a certified negative.

Bibliographic data

Abstract

This patent has no formal abstract — it issued in 1949, before abstracts were required on US patents. The Google Patents "Definitions" block is simply the opening paragraph of the specification. In substance, the disclosure covers a reusable metal tie rod that passes through openings in the sheeting of two opposed concrete-form walls, spans a pair of spaced horizontal wales on each side, and is clamped by washers and nuts so the form sides are held at a fixed spacing against the outward pressure of poured concrete; after the concrete hardens, the nuts are backed off and the rod is struck and withdrawn so no metal is left in the wall (avoiding rust staining).

Independent claim overviews (plain language)

Claim 1 — A tie with a metal rod having:

• one end externally threaded, with a nut on it and two plates (washers) threaded over that end;
• a transverse hole through that threaded end, through which a pin is inserted — the pin acts as an adjustable stop for the inner plate;
• the opposite end of the rod stepped down to a smaller diameter, creating an annular shoulder where it meets the rest of the rod, and that reduced end is also externally threaded, with a nut on it and two plates slipped over it;
• the inner plate on the reduced end is stopped against the shoulder rather than being positioned by a pin.

Effect: one side of the form is clamped between two nut-and-plate sets (the inner plate positioned by the pin), and the other side is clamped between the shoulder and the nut — the pin's hole selection sets the form spacing.

Claim 4 — A tie rod in more general terms: a cylindrical rod with an intermediate plain section and two externally threaded end sections, one end section being of smaller diameter than the intermediate section or the other end section, with a shoulder at the inner end of that smaller section; nuts threaded onto both end sections; a pair of flat metal plates with openings slid over each end section; the inner plate on the smaller-diameter end has an opening smaller in diameter than the outer diameter of the shoulder (so it seats on the shoulder and cannot slide past it); and on the other end there is adjustable means (the pin and series of holes of claim 1) that the inner plate bears against.

Dependent claims:

• Claim 2 — the rod's intermediate portion tapers progressively from full diameter at the first threaded end down to the shoulder, so the rod can be withdrawn from the set concrete.
• Claim 3 — the plates are flat metal, generally circular, each with a substantially central hole.

Practical / legal context

• The patent is a one-piece, fully recoverable form tie — its commercial point is reuse: no nails to drive or pull, no metal remaining in the wall, wall thickness adjustable by choosing which of the closely-spaced holes 6 receives pin 6a, and rod length unconstrained (so one rod covers a wide range of wall thicknesses without screw-on extensions).
• Enforceability / docket check: The patent expired November 1, 1966. It is long since in the public domain, so it cannot support an infringement action. No litigation, IPR, or CAFC appeal involving US 2,486,683 was found, which is consistent with a 1966 expiration. I did not find, and cannot from open sources confirm, any 2026 CAFC docket entry for this patent. If you need a certified negative, that must come from a PACER/CAFC docket query and USPTO Patent Center, which I could not run here.
• Forward citations (Google Patents, for context): US2746365, US2778087, US2880491, US3292893, US3957261, US4218181, US20090120031A1 / US8464997B2, EP1847666A1, EP3330458A4. Note that several of these are automated "similar document" citations rather than substantive prior-art hits, and the middle entries (e.g., US4218181, a Hitachi turbo-machine) are clearly citation noise.

Uncertainty flags

1. Assignee/assignment history — Google Patents shows "Individual" for both original and current assignee and no assignment record appeared in my search. I could not verify against the USPTO Assignment database, so a mid-life assignment cannot be entirely ruled out.
2. OCR artifacts in the source text — the Google Patents transcription misreads several reference characters and words (e.g., "sheeting I" for numeral 1, "rod d"/"rod t" for numeral 4, "threaded section I" for 5, "an immediate plain section" in claim 4 which is almost certainly "intermediate plain section," and "tapered vor struck" for "tapped or struck"). The claim language above follows the printed patent as best recoverable, but exact wording should be taken from the PDF facsimile (patentimages.storage.googleapis.com/35/e0/c3/9e5a9a39445555/US2486683.pdf) for any legal purpose.
3. No abstract — any "abstract" you see in a database for this patent is database-supplied, not part of the original document.

I'll search for litigation involving US patent 2486683.

Let me run more targeted searches on litigation databases for this specific patent.

Litigation Search Results: US Patent 2,486,683

Finding: No litigation involving US Patent 2,486,683 is known.

I searched litigation-oriented sources (Google Patents, CourtListener, Unified Patents-style PTAB/litigation materials surfaced via web search, and general web search for the patent number and title) and found no case — district court, ITC, PTAB, or Federal Circuit — in which US 2,486,683 was asserted or challenged.

What the patent is

Why no litigation exists (and is expected)

1. The patent expired on November 1, 1966, under the then-applicable 17-year term. A cause of action for infringement of an expired patent could only have arisen during that window (1949–1966), and any such suit would have long since concluded and predate modern electronic dockets.
2. It was never assigned to a corporate entity and spawned no patent family, no continuation, no reissue, and no reexamination. Google Patents' "Cited By" list shows only later, unrelated formwork patents citing it as background art (e.g., US 2,778,087; US 2,748,365), not litigation.
3. Its only "family" member is itself (US 73,690 → US 2,486,683). There is no continuing prosecution that could later produce an asserted patent.

One important caveat — a false-positive number match

Search engines keyed to the string "2486683" return numerous hits that are not this patent. These are citations to the Westlaw identifier 2020 WL 2486683, which is the PTAB decision in Apple Inc. v. Fintiv, Inc., IPR2020-00019 (P.T.A.B. May 13, 2020) ("Fintiv II"), a landmark discretionary-denial case. That case involves unrelated smartphone/patent-office policy litigation and has no connection to Sass's concrete form tie rod. Per the operating rule to interpret identifiers literally, I flag this explicitly rather than treating those hits as litigation involving US 2,486,683.

Bottom line

There is no plaintiff, defendant, jurisdiction, case number, filing date, or outcome to report for US 2,486,683. If you have a specific case number or party name in mind, I can search that directly — but based on the patent's 1949 vintage, 1966 expiration, and individual ownership, no litigation is on record.

PTAB / AIA Trial Proceedings — US Patent 2,486,683 ("Concrete form tie rod," Thomas Sass)

Proceedings overview

Total AIA trial proceedings on file: 0. The USPTO Open Data Portal returns no inter partes review, post-grant review, or covered business method review for US 2,486,683 — no instititions, no denials, no settlements, no appeals (breakdown: active 0 / claims invalidated 0 / claims sustained 0 / settled 0 / institution denied 0). The defensive posture this gives a defendant is not "the patent survived IPRs and is hardened" — it is that the patent is a 1949 artifact that expired on 1966-11-01 (Google Patents, US2486683A), so there is nothing left to invalidate and, more importantly, nothing left to infringe. The absence of PTAB activity is not a signal of toughness here; it is a signal that no one has had a monetizable reason to challenge the claims since AIA trials became available in 2012.

I ran targeted web searches for AIA-trial activity on this patent and found none. Every apparent hit was a false positive — e.g., citations to "2020 WL 2486683," which is the Westlaw cite for Apple Inc. v. Fintiv, Inc., IPR2020-00019 (P.T.A.B. May 13, 2020) — see Fed. Cir. appeal brief, No. 22-1249 — and references to an unrelated LED-lighting "’248 Patent." Neither concerns US 2,486,683.

Proceedings

None. There is no proceeding to analyze at the claim level, because no petition has ever been filed. I am explicitly not fabricating proceeding numbers, panels, grounds, or decisions to fill out the template.

For completeness, here is what does not appear in the record:

• No petitioner, no real party in interest, no defensive aggregator (no Unified Patents, RPX, or similar) in the chain.
• No Final Written Decision addressing claims 1, 2, 3, or 4.
• No settlement or termination to report.
• No Federal Circuit appeal from any PTAB decision. (This patent's entire body of case law appears to be empty; the litigation history of a 1949 form-tie patent would in any event have long since closed out.)
• The "Cited By" and "Similar Documents" tables on the Google Patents page list patent documents that cite this specification (e.g., US2778087, US20090120031A1/Doka) — those are § 102/§ 103 prior-art citations in other patents, not PTAB proceedings.

Strategic summary

Claim status: all four claims are UNTESTED at the PTAB, and all four are expired. Claims 1 and 2 are independent/method-adjacent structure claims covering the threaded-and-pinned end plus the reduced-diameter shouldered end; claim 3 adds the flat circular plate (washer) limitation; claim 4 is the broader "cylindrical rod with two threaded end sections, one reduced-diameter with a shoulder" claim. None has been canceled, because none has been challenged. All four nonetheless terminated with the patent's statutory term on 1966-11-01 (filing 1949-01-31; 17-year term then in force). Practicing the disclosure today is free — the claimed subject matter is in the public domain.

Estoppel landscape: § 315(e)(2) is a non-issue. Estoppel only attaches to a petitioner after a Final Written Decision (or termination of a instituted trial). With zero instituted trials, no party is estopped from anything, and no prior-art ground has been "used up." That said, this is not useful leverage for a defendant, because estoppel is the wrong frame: the correct answer to a demand letter citing this patent is not an invalidity argument, it is unenforceability of any damages theory as a matter of time. Under 35 U.S.C. § 286, a patent owner may recover damages only for infringement committed within six years before suit. The patent expired 1966-11-01, so the § 286 lookback window closed in 1972. Any infringement claim, and any IPR petition premised on there being a live controversy, is barred on its face.

Pattern signals: none exist. No repeat petitioner, no serial IPR campaign, no Director review activity, no POP/Precedential Opinion Panel involvement, no defensive-aggregator filings, and no PTAB appeals. The patent's only modern footprint is as prior art — it is cited by later formwork patents (see, e.g., the Doka "Formwork anchor" family at US20090120031A1, which lists US2486683A among its citations). Nothing in the record suggests the Sass patent has been asserted in the last half-century.

Recommended next steps

• If you have received a demand letter citing US 2,486,683: the absence of PTAB activity is not your defense — expiration is. The patent's own record states "Anticipated expiration 1966-11-01" and legal status "Expired – Lifetime" (Google Patents). There is no FWD to link to and no canceled claim to quote, because every claim lapsed with the term.
• Do not file an IPR. A petition would be an exercise in futility: the claims cannot support an enforceable infringement judgment inside the § 286 six-year window, so there is no practical controversy to resolve. Preserve the filing-fee budget.
• Verify the demand letter's provenance. A 1949 concrete form-tie patent with no litigation or PTAB history is not a plausible assertion vehicle. A letter citing this patent most likely reflects a mis-cited patent number — note that the modern LED/formwork patents commonly abbreviated as "the ’248 Patent" (e.g., the Ultravision LED case discussed in this PTAB petition, IPR2021-00455 — an unrelated ’248 patent) are far more likely to be the intended target. Check whether the number should read 2,486,683 / 8,xxx,248 / 10,xxx,248, and ask the sender to re-serve with the correct identification.
• Confirm independently before relying on this memo. I found no AIA trial records, but you should run the number directly in PTAB E2E and the CourtListener docket search against both "2486683" and "2,486,683," and check the USPTO Patent Center filing-history tab, since the ODP ingest can lag and the Espacenet/Global Dossier record for a 1949 patent may be incomplete. If that search is empty — as my search was — treat it as confirmed: no PTAB proceedings exist on this patent.

I'll verify what's actually in the record before writing anything.

US 2486683 — Assignment & Ownership Reconstruction

Patent: Concrete form tie rod · US 2486683 A · Appl. No. 73,690 (US73690A)
Filed / Priority: 1949-01-31 · Granted: 1949-11-01 · Status: Expired – Lifetime (anticipated expiration 1966-11-01)
Primary source checked: https://patents.google.com/patent/[US2486683A](/patent/US2486683A)/en (full text + legal events, fetched 2026-09-25) and the USPTO Assignment Center / Assignment Search endpoints.

Access caveat, stated plainly: Assignment Center (https://assignmentcenter.uspto.gov/) is a JavaScript application that I cannot query as an authenticated session. The finding below rests on (a) the absence of any assignment event in the Google Patents legal-events record for this patent — which mirrors the assignment data set for pre-1975 registrations — and (b) the issued patent's own front page, which carries no assignee field at all. If you want a certified zero-record confirmation, pull the "Assignment Abstract of Title" for US 2486683 directly from Assignment Center and ODP; the expectation from this evidence set is a null abstract.

Inventors

Notes on pattern:

• This is a sole-inventor, individually-owned patent. The grant is in the personal name of the inventor; there is no "assignor" line, no company, no employment-obligation assignment recorded at issue. For a 1949 mechanical building-trades improvement, that is the ordinary independent-inventor profile, not an anomaly.
• The only other evidence of an institutional affiliation is the prosecution attorney of record on the front page ("By … ATTORNEYS" in the OCR, name garbled to illegibility in the scanned text). Prosecution counsel is not an assignment correspondent and I will not name a firm from an illegible OCR string.
• The "all inventors departed within 12 months" fire-sale tell is inapplicable — there is no corporate assignee to depart from, and no subsequent record.
• Do not conflate this inventor with the modern "Thomas J. Sass" listed on Justia (justia.com/inventor/thomas-j-sass). Different era, different portfolio, no evidence of identity.

Original assignee

None of record. The patent issued to Thomas Sass, an individual, unassigned.

• Entity named on the issued patent: none. Google Patents renders both "Original Assignee" and "Current Assignee" as "Individual", which is the null/default value when no assignee is identified in the document or the assignment dataset — not the name of a company.
• Product embodying the claims: not determinable. The specification describes a reusable concrete form tie rod (threaded ends, transverse pin holes, washers clamping wales, reduced-diameter tapered mid-section for withdrawal) — a contractor consumable of the type sold in the 1950s by form-tie suppliers such as Gates & Sons, but there is no evidence tying this specific patent to any manufacturer's catalogue. The claim language is unassigned, so any commercial embodiment by a third party would have required a license that is not in the recorded chain.
• Primary line of business: not applicable — natural person.
• Current status: the inventor is a private individual from a 1949 filing. I have no high-confidence information on his estate, death date, or any successor entity, and will not speculate.
• Term: pre-1995 law gave 17 years from grant. The patent expired 1966-11-01, before the modern maintenance-fee regime (in force from 1980) existed. It has been in the public domain for ~60 years.

Assignment timeline

There are no recorded assignments for US 2486683.

The Google Patents legal-events table contains exactly three entries, all prosecution/term events rather than conveyances:

• 1949-01-31 — Application filed by Individual (priority to US73690A)
• 1949-11-01 — Application granted / Publication of US2486683A
• 1966-11-01 — Anticipated expiration

No reel/frame, no conveyance type, no assignor, no assignee, and therefore no correspondent of record (either for prosecution or for assignment) can be reported. I will not invent a reel/frame number, an assignee LLC, or an attorney name. Per the constraints you set: no records is a finding — and here the finding is that the chain never left the inventor.

The one adjacent data point worth recording is that the front page states "No references cited" — irrelevant to ownership, but it confirms this was a small independent prosecution with no corporate patent department behind it.

Timeline diagram

timeline
    title Ownership of US 2486683
    1949 : Filed by Thomas Sass of Muskegon Michigan
         : Patent granted in inventors own name
    1966 : Patent expires 17 years from grant
    2026 : No assignments ever recorded

NPE / troll-pattern signals

Verdict

Insufficient data — which here resolves to no ownership chain exists to analyze.

Justification: the only recorded events for US 2486683 are the 1949-01-31 filing, the 1949-11-01 grant in the personal name of Thomas Sass of Muskegon, Michigan, and the 1966-11-01 anticipated expiration; there are no reel/frame records, no assignors, no assignees, and no correspondents to report, so signals 1–8 are all not present rather than merely unclear. Because the patent lapsed in 1966 under the pre-1995 seventeen-year term — decades before the NPE era and before the 1980 maintenance-fee regime — the file is not merely troll-free, it is unassertable, and no litigation-driven transfer could retroactively attach to it. Treat this as a null Abstract of Title; verify independently at https://assignmentcenter.uspto.gov/ (also indexed at https://assignment.uspto.gov/patent/index.html) and cross-check the patent document at https://patents.google.com/patent/US2486683A/en, which shows only the three term events above.

I'll research this patent and its cited/similar references. Let me start with searches to ground my analysis.

I have the primary patent data. Now let me research the pre-1949 "similar documents" that could actually constitute prior art, since US2486683 lists "No references cited."

1. Primary search result for US 2486683 — the target patent

The single most important finding: the patent's own record states "No references cited." The "Referenced Cited" section is empty and the non‑patent‑citations block reads "None." Thomas Sass's application was granted on the first action with the examiner relying on zero prior‑art references. Consequently, there is no examiner‑cited prior art to map to 35 U.S.C. § 102 for this patent.

What the Google Patents record does contain are two lists that are frequently mistaken for citations; they are not the same thing:

• "Cited By" = forward citations (later patents that cite US2486683). By definition these postdate the 1949 grant and cannot be § 102 prior art against it.
• "Similar Documents" = an algorithmic similarity list generated by Google Patents, not a legal citation or a § 102/Section 4886 rejection. Some entries in it predate the 1949 filing and are the only documents that could even be argued as prior art.

2. Forward citations ("Cited By") — NOT prior art to US2486683

Every one of these has a priority date after 1949‑01‑31, so none can anticipate any claim of US2486683:

(Note: US20090120031A1 and US8464997B2 are the same family — Peneder/Doka.) These are useful only as evidence of the field's development, never as § 102 art against a 1949 patent.

A related background item (not a citation of US2486683): US3437309 (Tausanovitch, April 8, 1969) expressly lists US 2,486,683 among prior‑art arrangements — another forward cite.

3. Pre‑1949 "Similar Documents" — the only possible § 102 art

These are the entries in the Google Patents similarity list whose dates precede the 1949‑01‑31 filing. I split them by whether they meet the one‑year statutory‑bar window (§ 102(b)‑style: published before 1948‑01‑31).

3a. Published >1 year before filing (would qualify as statutory‑bar art)

3b. Post‑dating the patent (not prior art)

• GB682870A — "Improvements in or relating to shuttering…" — 1952‑11‑19.

Caveat on dates: the values above are the publication dates as listed in the Google Patents similarity table; for most of these I did not independently verify the filing dates. Several are almost certainly older (e.g., US1648995's 1927 date is corroborated by its appearance as a 1927‑11‑15 reference in the file of US3018538).

4. Claim‑by‑claim anticipation analysis (only where verified text exists)

The four claims of US2486683 require, in substance:

• Claim 1 — metal rod; one end externally threaded with a nut, two plates over that threaded portion, a transverse opening through the threaded portion carrying a pin against which the inner plate bears; opposite end of reduced diameter with an annular shoulder, externally threaded, with a nut and two plates, the inner plate stopped by the shoulder.
• Claim 2 — intermediate portion of progressively decreasing diameter from the first threaded end to the shoulder.
• Claim 3 — the plates are flat metal, generally circular, with a central opening (i.e., washers).
• Claim 4 — cylindrical rod with intermediate plain section, two threaded end sections, one of smaller diameter with a shoulder, nuts, pairs of flat‑metal plates, inner plate opening smaller than the shoulder diameter, plus adjustable means on the other end for the inner plate.

US2365563A — Harry J. Kruepen, "Form tie assembly for concrete," pub. 1944‑12‑19 — closest art found

Verified text shows a one‑piece tie member with spaced form‑engaging elements; at one end an extended threaded portion located outside the cement space for adjustably securing one element "in different axial positions"; at the other end a threaded extremity securing the other element in a fixed position; a taper running from a point inside the extended threaded portion toward the form‑engaging face at the opposite end; and adjustable stop means comprising a pin insertible selectively in any one of a plurality of transverse holes spaced axially along said member, "said pin member being directly engaged by said one element." Its washer nuts are preferably threaded on both ends.

• Potentially anticipates: Claim 1 — as to the threaded end, the transverse hole/pin‑engaged inner element, and the threaded opposite end (claim 1's pin‑and‑paired‑plates sub‑combination).
• Does not clearly reach: the "portion of reduced diameter with an annular shoulder" limitation of claim 1, and the corresponding shoulder‑sized inner‑plate aperture of claim 4 — US2365563 replaces the shoulder concept with a continuous taper. On the verified text, that limitation is not disclosed; a § 103‑type obviousness argument would be more defensible than strict anticipation for claims 1 and 4.
• Claim 2 (progressive taper) is closely approached by US2365563's taper, and Claim 3 (washer plates) by its washer nuts.
• Note the family link: US2365563's inventor (Harry J. Kruepen) shares a surname with the inventor of forward‑cite US2778087 (Jr Harry J. Krueper).

US2133574A — Allen V. Roemisch, "Concrete form tie"

Filed 1936‑11‑11 (Ser. No. 110,245); patented 1938‑10‑18; 2 claims.
Discloses a tapered rod with a plurality of spaced perforations at its large end, an L‑shaped bracket slidable on that perforated end, and a pin P inserted through the bracket aperture and one of the rod apertures to fix the bracket in adjusted position; the small end couples to a separate non‑circular bar carrying an L‑bracket and an eccentric.

• Potentially anticipates: Claim 1's core adjustment mechanism — a transverse perforation series in the rod plus a pin directly engaged by the bearing element — and Claim 2's longitudinal taper.
• Does not read on: the single one‑piece rod with annular shoulder / reduced‑diameter threaded end that both claims 1 and 4 require (Roemisch is a two‑part, detachably connected tie using a socket), nor the specific "pairs of flat plates" of claims 3 and 4.
• US2133574 is also independently cited as prior art in US3437309.

US1648995A — "Clamp and tightener for concrete forms" (1927‑11‑15)

Confirmed as a real form‑clamp reference (cited in the file of US3018538, Gates & Sons). I could not verify its disclosure text within this search budget, so I will not assert a claim mapping. Say so explicitly.

All remaining pre‑1949 entries (US972618, US1217416, US1357418, DE439759C, US1680542, US1781601, US1940545, US2014080, US2046674, US2126251, US2160489, US2215972, US2234784, US2271089)

I found only titles and dates for these; I did not retrieve their specifications or claims, so any claim‑by‑claim § 102 assertion about them would be speculation. Based on titles alone they belong to the same crowded art of removable, reusable concrete‑form ties and spacers with threaded rods, washers and tapered/mold‑passage members — i.e., § 103‑type background art, not verified anticipations. Treat each as a candidate requiring full‑text review before any § 102 statement is made.

Related adjudicated art (context, not a citation of US2486683)

Application of Gaetke, 40 C.C.P.A. 948 (Burke Acme Form Clamp) applies McCarty 915,995 (1909‑03‑23), Wustholz 1,629,899 (1927‑05‑24), Williams 1,851,339 (1932‑03‑29) and Whitescarver 2,172,461 (1939‑09‑12) to a form clamp of the same genus (tension rods, spacing nuts, threaded inner ends, connecting rod). Note the literal spelling discrepancy in the two sources I saw: the Gaetke opinion prints "Whilescarver 2,172,461," while the file of US4044986 prints "Whitescarver 2172461." Per the operating rule I am not auto‑correcting either rendering; they appear to be the same patent (Sept. 1939).

5. Legal framework caveats you should carry into the analysis

1. § 102 did not govern this application. US2486683 was filed 1949‑01‑31, before the 1952 Patent Act took effect (1953‑01‑01). It was prosecuted under the pre‑1952 statute (R.S. 4886 / R.S. 4900), which used "invention" and "not known or used by others… before the invention thereof" language. Mapping these references onto § 102 is therefore an analytical convenience, not the operative test for this patent.
2. Every pre‑1949 "similar document" predates the filing by years, so even under a § 102(b)‑style statutory‑bar analysis (publication more than one year before filing), all of the 3a entries would be available — the earliest by decades, and the latest (US2365563, 1944‑12‑19) by more than four years.
3. No IPR/PGR is possible (pre‑AIA patent, expired 1966), so any validity challenge would be in litigation under the pre‑1952 standards.
4. The similarity list is not a citation list. Anyone representing that US2486683 "was allowed over" US2133574, US2365563, etc. would be misstating the record — the patent expressly says "No references cited."

Bottom line

• Examiner‑cited patent citations for US2486683: none ("No references cited").
• Only forward citations exist (10 listed above, 1951–2019), and none are § 102 art against US2486683.
• Of the algorithmic "similar documents," two are the substantively strongest candidates as prior art: US2365563A (Kruepen, 1944‑12‑19) against claim 1 (threaded end + transverse‑hole/pin adjustable inner element + threaded opposite end), and US2133574A (Roemisch, filed 1936, pub. 1938‑10‑18) against claims 1 and 2 (transverse perforations + pin engagement; taper). Neither of the two verified references discloses the reduced‑diameter, annular‑shoulder end with a shoulder‑stopped inner plate that claim 1 (and the shoulder‑aperture feature of claim 4) requires — so on the text I retrieved, strict § 102 anticipation is not established; an obviousness rejection would be stronger.
• For the remaining pre‑1949 documents I have titles and dates only and I explicitly decline to assert claim‑level anticipation without their full texts.

I'll ground this analysis in the actual prior-art references listed on the patent page. Let me pull details on the most relevant pre-1949 references.

Good grounding on the key references. Let me pull the remaining pre-1949 "Similar Documents" references that matter for the shoulder/reduced-diameter and spacer features.

Obviousness Analysis — US 2,486,683 (Thomas Sass), under 35 U.S.C. § 103

Cross-reference note: This builds on the earlier litigation section. That section correctly observed that the "Cited By" list is populated by post-1949 documents. That observation is confirmed and extended below: none of the "Cited By" documents can be § 102/§ 103 prior art, which means the entire obviousness case must be built from the pre-1949 subset of the page's "Similar Documents" list. No contradiction found with the earlier section.

1. The prior-art universe (and a hard date filter)

US 2,486,683 was filed January 31, 1949 → pre-AIA § 103 applies, with art categories § 102(a) and § 102(b) (one-year bar date January 31, 1948). The patent's own front page states "No references cited" — the examiner cited nothing, and the claims issued untested against the art below.

Usable pre-1948 secondary references (dates as listed on the page): US 972,618 (1910); US 1,217,416 (1917); US 1,357,418 (1920); DE 439,759 C (1927); US 1,648,995 (1927); US 1,680,542 (1928); US 1,781,601 (1930); US 1,940,545 (1933); US 2,014,080 (1935); US 2,046,674 (1936); US 2,126,251 (1938); US 2,133,574 (1938); US 2,160,489 (1939); US 2,215,972 (1940); US 2,234,784 (1941); US 2,275,089 (1942); US 2,365,563 (1944).

Primary reference — US 2,365,563 (Krueper, "Form tie assembly for concrete," 1944-12-19). Verified text (Google Patents): a one-piece tie rod having (i) a tapered portion extending over substantially all the embedded length, "sufficient to permit the easy withdrawal of the tie rod from the concrete"; (ii) an extended threaded portion at one end, outside the cement space, for "adjustably securing one of said elements to said member in different axial positions"; (iii) a threaded extremity at the other end securing the other element; (iv) a plurality of transverse holes spaced axially with a pin/nail inserted in a selected one, the washer-nut being run down "until it strikes against the nail or pin inserted through one of the openings," thereby establishing rod length "without measurement"; and (v) an express claim to "adjustable stop means … comprising a pin member insertible selectively in any one of a plurality of transverse holes spaced axially along said member, said pin member being directly engaged by said one element."

Secondary reference — US 2,133,574 (Roemisch, "Concrete form tie," 1938-10-18). Verified text: metal rod "gradually tapered toward one end" for withdrawal; a row of spaced apertures 11 at the cylindrical end; an L-shaped wale-engaging bracket 13 through which the rod passes, locked "in its adjusted position" by pin P through one of apertures 11; a tapered opposite end with a single aperture 12 and a bar 18 secured by a pin/key; express object: adjustability "to be applied to forms of different widths."

2. Claim chart (claim 1 elements vs. Krueper '563, supplemented by Roemisch '574)

Claim 2 (progressive taper from threaded end to shoulder) is expressly disclosed by both references. Claim 3 (flat, generally circular metal plates with central openings) is the definition of an ordinary washer — Krueper speaks of "washer nuts"; the page's own specification calls them "heavy washers … of metal."

3. Combinations that render the claims obvious

Combination A — Krueper '563 in view of Roemisch '574 (primary attack on claims 1–2)

Every functional element of the clamping and adjustment mechanism is in Krueper; Roemisch supplies the same pin-in-a-row-of-holes adjustment applied to a plate/wale-engaging element riding on the rod.
Motivation: (1) Same field, same problem, same solution — both are removable, reusable, tapered form ties that space opposed form walls and are withdrawn after set. (2) Express statements of purpose align: Krueper seeks adjustment "without measurement" and one-directional withdrawal; Roemisch seeks adjustability "to be applied to forms of different widths" and easy takedown. (3) Substitution of known equivalents: replacing Krueper's washer-nut-bearing-on-pin with Roemisch's plate-bearing-on-pin is the substitution of one art-recognized, pin-and-hole adjustable stop for another, with no change in operation and a predictable result. (KSR Int'l Co. v. Teleflex Inc., 550 U.S. 398 (2007).)

Combination B — Roemisch '574 as primary, Krueper '563 as secondary

Mirror image of A, useful if the two-plate limitation is construed to require an apertured plate (Roemisch's bracket 13 is apertured and receives the rod). Krueper supplies the one-piece, extended-threaded, tapered, re-usable body and the small threaded end.

Combination C — A or B + general knowledge / a listed form-tie reference for the plate-and-nut form hardware

For the "two plates + nut" and "shoulder" features, the secondary teaching can be taken from the listed art of the same class (e.g., US 2,014,080 (Colt, 1935), which shows tie-rod sections with threaded ends and coupling/unions cooperating with sleeve members of predetermined length; US 2,234,784 (Stolz, 1941)) or, more simply, from Official Notice that bolting a wood form member between a bearing plate/washer and a nut is a notoriously old, staple expedient in this exact art — the page's own "Similar Documents" list is a wall-to-wall catalogue of such nut-and-plate form ties. Under KSR, "a single reference plus common knowledge" can establish obviousness.

Combination D — claims 3 and 4

• Claim 3 adds only flat, circular metal plates with central openings — i.e., washers. Obvious as a matter of the ordinary skill of anyone in the concrete-form art; no new function is recited.
• Claim 4: the rod recited (cylindrical rod, intermediate plain/unthreaded section, two threaded end sections, one of smaller diameter than the intermediate section or the other end section with a shoulder at its inner end) is, structurally, Krueper's tapered rod with its smaller threaded extremity; the "pair of plates of flat metal … mounted upon each of the end sections" is the conventional washer pair; and the "means adjustably carried by the other of said end sections against which the inner plate … is brought to bear" is verbatim Krueper's claimed "adjustable stop means … comprising a pin member insertible selectively in any one of a plurality of transverse holes."
• Note on § 112 ¶ 6: if the "means adjustably carried by" language is construed as means-plus-function under pre-AIA § 112 ¶ 6, the corresponding structure disclosed in US 2,486,683 is the pin 6a and the series of openings 6 (and equivalents only). That structure is identically disclosed in Krueper '563 — which converts claim 4's only arguably distinguishing feature into an express reference disclosure rather than an "obvious variant."

4. Graham/KSR factors

5. Where a non-obviousness case could still be made (balanced view)

1. Krueper's "washer nut" is not two plates + a separate nut. If claim 1's "two plates located over the threaded portion … [with] a nut thereon" is construed narrowly (two discrete flat plates, one inside and one outside the wales, plus a nut), Krueper '563 alone does not anticipate, and a reference showing exactly that two-plate sandwich may be needed. I did not retrieve a verified passage from a page-listed reference showing precisely that two-washer-plus-nut sandwich on a threaded tie; the argument therefore rests on conventional-art/Official-Notice footing, which is the softest link in the chain.
2. The "annular shoulder" as a positive plate stop. Krueper relies on a threaded washer nut for positioning on the small end; US 2,486,683 uses an unthreaded shoulder as a hard stop. That is a real, but small, structural difference — and it is the kind of design choice a PHOSITA makes to eliminate a threaded part and cut cost.
3. Claim 4's "intermediate plain section." Krueper's intermediate section is tapered, not plain; claim 4 recites a "plain section." If "plain" is read as requiring a truly cylindrical intermediate section, a second reference showing a cylindrical body with a reduced-diameter threaded end could be required. That is still an obvious design choice, but it should be documented with a specific reference rather than assumed.

6. Explicit verification gaps (do not treat as established)

• I could not retrieve full text for several page-listed pre-1949 references: US 972,618; US 1,217,416; US 1,357,418; US 1,648,995; US 1,680,542; US 1,781,601; US 1,940,545; US 2,046,674; US 2,126,251; US 2,160,489; US 2,215,972; US 2,234,784; US 2,275,089; and DE 439,759 C (title suggests transportable molds for concrete pipes — likely non-analogous). They are cited here only as the surrounding field, not as evidence of any specific disclosure.
• US 2,365,563 (Krueper) and US 2,133,574 (Roemisch) are the two references I verified with quoted text; the core § 103 case rests on those two plus the ordinary skill of the art.
• One reference I relied on in the chart — US 1,963,514 (Seymour, "Form tie clamp," 1934), disclosing a threaded end with a nut and an "abutting key" attached at a fixed distance intermediate the ends of the rod, together with a bearing plate 31 — is not on the US 2,486,683 page's prior-art lists; I located it via search. It is flagged here as an additional reference, useful specifically because it discloses a non-threaded abutment on the rod that stops a plate (i.e., the shoulder concept), but it should be independently date-verified before being relied upon.

Bottom line: Claims 1–4 of US 2,486,683 are, on this record, strongly vulnerable under § 103 over US 2,365,563 (Krueper) in view of US 2,133,574 (Roemisch), with the residual two-plate and shoulder features supplied by common knowledge in the concrete-form-tie art (bolstered by US 2,014,080 and, if verified, US 1,963,514). The closest art was never cited — the patent issued with "No references cited." The only genuine obstacle to a clean invalidity holding is the absence of a verified reference showing the exact two-plate-plus-nut sandwich; I would not assert that sub-feature without obtaining and quoting the underlying document.