US 3218095

I'll search for this patent's litigation and docket history, then summarize based on the authoritative full text provided.

US 3,218,095 — Summary and Litigation Check

Important search-result finding: I found no USPTO litigation records, no CAFC 2026 docket entries, and no Federal Circuit or district court activity involving U.S. Patent No. 3,218,095. My searches of 2026 Federal Circuit coverage (WilmerHale Federal Circuit Patent Watch, Patterson Sheridan weekly summaries, Gibson Dunn updates, IPWatchdog, Mealey's) returned opinions citing only modern patent numbers (e.g., 9,803,256; 7,356,482; 7,290,864; 10,039,483) — nothing matching 3,218,095. This is expected: the patent's anticipated expiration was 1982-11-16, per Google Patents' legal-status entry ("Expired – Lifetime"), so it is long since unenforceable and could not appear on any 2026 docket. If you have a specific case caption you believe asserts this number, I do not have authoritative confirmation of it.

Bibliographic Data

Abstract: This 1965-era patent has no formal abstract — the Google Patents record contains no abstract field. The closest equivalent is the "Objects of the Invention" discussion in the specification.

References cited by the Examiner:

• US 2,444,119 — Thorn et al., "Packing ring," Garlock Packing Co., issued 1948-06-29
• US 2,944,840 — Sumner D. Wiltse, "Tube coupling having a reinforced sealing and locking ring," issued 1960-07-12 (same inventor)
• US 3,027,179 — Sumner D. Wiltse, "Tube coupling structure having combined seal and retaining means," issued 1962-03-27 (same inventor)

Family / related filings shown on Google Patents: A priority link to US 364,402 → US 3,291,496 A ("Sealing ring," Vibraseal Corp, filed 1964-05-04). Note that the FreePatentsOnline record for US 3,304,104 ("Tube coupling," Vibraseal Corp) lists application number US 364,403 and a 1964-05-04 filing date, and cites 3,218,095 as a reference. I flag this because the serial numbers 364,402 and 364,403 are distinct identifiers; I am not auto-correcting or merging them.

Plain-Language Overview of the Claims

The patent has four claims: one independent claim (claim 1) and three dependent claims (2, 3, 4).

Note on source reliability: The "Claims (1)" rendering on Google Patents shows only claim 1 and contains visible OCR corruption around the phrase beginning "…OF SAID FLANGES AND THE THREE LATERALLY PLANAR SURFACES…". I relied instead on the cleaner "What I claim as my invention is:" passage in the specification body for claims 1–4.

Claim 1 (independent) — the coupling assembly

A tube coupling made of three cooperating parts:

1. A tubular fitting with a cylindrical outer surface centered on the fitting's axis. Inside, roughly midway along its length, it has an inwardly projecting annular portion whose cylindrical inner surface is concentric with the outer surface.
2. Two annular grooves opening inwardly, one on each side of that central portion. Each groove has three connected planar sides: the middle side is cylindrical (concentric with the outer surface) and the two flanking sides each form equal obtuse angles with it — i.e., a trapezoidal/three-sided groove profile.
3. Outer annular shoulders beyond the grooves, projecting inwardly, with cylindrical inner surfaces concentric with the outer surface and substantially aligned with the central annular portion's inner surface.
4. Two aligned tubes of substantially equal diameter extending axially, with substantially vertical ends facing one another. Each tube end has an outwardly projecting lateral flange having a cylindrical outer edge that seats (surface-to-surface) against the central annular portion's inner surface.
5. Flange geometry: the facing flange faces are substantially vertical and substantially flush with the tube ends (so the tube bores meet in a continuous flat-face butt). The outer face of each flange is an upwardly and inwardly inclined planar surface, oriented opposed to and substantially parallel with the outermost planar side of the corresponding groove.
6. The retaining/sealing means: two sealing rings, each of uniform hexagonal cross section throughout its circumference, and each including means to exert a continuous radially outwardly acting force on at least two of the planar sides. The result is that four planar surfaces of each ring make surface-to-surface sealing contact with (a) the entire periphery of the inclined flange face and (b) the three planar sides of the fitting groove.

In short: the hex-section ring acts simultaneously as the axial retainer that pulls/holds the flanged tube ends together and as the fluid seal, eliminating bolts, lugs, threads, or bosses.

Claim 2 (dependent on claim 1)

Specifies the "means to exert a force": an annular reinforcing tubular helix embedded within each sealing ring, in spaced relation to the ring's surface (i.e., a spring embedded in the rubber body, not exposed at the surface).

Claim 3 (dependent on claim 2)

Further specifies that the reinforcing helix is an annular spiral wire spring.

Claim 4 (dependent on claim 1)

Specifies a dimensional relationship: the radial clearance between each tube's exterior surface and the outer annular portion of the fitting is slightly greater than the cross-sectional dimension between opposed planar surfaces of each sealing ring. This sizing is what allows each ring to be slid along the tube, past the outer shoulder, and snapped into the groove into sealing engagement with the inclined flange face and the three groove sides.

Specification Highlights (context beyond the claims)

• Each sealing ring is preferably an annular solid rubber/rubber-like body (31) with an embedded metallic spring helix (32); the helix is a hollow tubular spiral wire spring with convolutions of substantially circular cross section and uniform diameter. The patent states the helix has "great shear resisting ability" and holds the rubber body against displacement.
• The ring's inside diameter is smaller than the flange diameter, but the ring is radially expansible so it can be stretched over the flange — enabling an alternative assembly sequence described in Figs. 5–12 (stretch ring over flange, insert tube through fitting, alternately lower/raise the tube to insert the ring into the groove, then retract the flange against the seated ring).
• Preferred assembly (Fig. 4): insert both flanged ends face-to-face into the central annular portion, then sleeve the rings along the tubes and slide them into the grooves.
• The fitting has beveled/tapered outer edges (36, 37) to ease insertion of the flanges and to admit a longitudinally split ring (38) with a finger-piece flange (39), which can be used to force the flanges and rings into final assembled position or tighten the joint.
• When assembled, the rings are under compression, retaining the flanges and providing fluid-tight joints. Coupled tubes present a continuous smooth inner bore for the conveyed fluid.
• Optional features: a thin annular gasket between the flange faces; disassembly via a hook engaged with the rings or via cap screws/bolts threaded through the fitting above the rings to push the rings out.

(Characterization note: the specification text as retrieved contains considerable OCR noise — e.g., "l2" for "12," "3%" for "30," "lit)" for "10," and a duplicated figure caption for FIGURE 3. I have interpreted these literally as OCR artifacts of the same numerals, not as separate reference characters.)

Uncertainty Flags

• No abstract exists for this patent; I did not fabricate one.
• No CAFC 2026 or other litigation/docket activity was found for 3,218,095, and given its 1982 expiration this is consistent.
• Google Patents explicitly disclaims accuracy of assignee data; Vibraseal Corp is the only assignee listed, with no recorded reassignments.
• The Google Patents "Claims (1)" tab renders only one claim and with corrupted text; the four-claim count comes from the specification's own "What I claim as my invention is" list, which I treat as authoritative.

I'll search for litigation involving US patent 3218095 across the sources you specified.

The initial searches returned no relevant litigation. Let me refine with more targeted litigation-database queries.

No relevant hits yet. Let me query the specific litigation portals directly.

Summary of Search Results

Bottom line: I found no evidence of any litigation involving U.S. Patent No. 3,213,095.

Searches performed

I ran queries against general web indexes, Google Patents, and targeted litigation-oriented queries (including a site:portal.unifiedpatents.com query and a CourtListener-targeted query). The Unified Patents query returned zero results, and no PACER/CAFC docket, complaint, or judgment referencing this patent surfaced.

Why this is unsurprising

• US 3,213,095 ("Tube coupling") was filed 1964-04-16, granted 1965-11-16, assigned to Vibraseal Corp, inventor Sumner D. Wiltse. Its legal status on Google Patents is "Expired – Lifetime," with an anticipated expiration of 1982-11-16.
• The patent has been expired for over 40 years. Its only citations by later patents are as prior art (e.g., it is listed as related art in AU 751817 B2, ITT Manufacturing Enterprises, "A Clamping Spring Ring"), not as a patent-in-suit.
• Note: litigation databases such as Unified Patents and CourtListener are largely populated with cases from the 2000s onward, so any 1960s–1970s enforcement activity (which predates these systems) would likely be undocumented in searchable digital sources even if it occurred. I cannot rule that out, but I found no trace of it.

Important disambiguation (avoiding false matches)

My searches surfaced several irrelevant hits that contain the digit string "3218095" — none relate to this patent:

• A Chinese phone number (0475-3218095) on an IP protection center page.
• A Florida LLC's FEI/EIN number (93-3218095).
• EP 0095085 A1 and DE 3218095 A — unrelated European/German patent documents.
• U.S. Patent 5,980,809 (the '809 patent) in a Maytag washing-machine-basket claim-construction opinion — a different patent.
• U.S. Patents 6,275,213 / 6,332,133 etc. ("'213 patents") in Immersion v. Sony — unrelated to patent number 3,213,095.

Related family patents (not litigation findings)

For completeness, the same family includes:

• US 3,291,496 ("Sealing ring"), priority 1964-04-16, filed 1964-05-04, Vibraseal Corp.
• US 3,304,104 ("Tube coupling") and US 3,334,929 ("Tube coupling"), both Vibraseal Corp.

Caveats

• I did not find litigation, but I also cannot prove a complete negative for pre-digital-era suits (pre-1990) that were never indexed electronically.
• If you want a higher-confidence answer, the definitive sources would be microfilm/legacy PACER archives, the Federal Circuit's predecessor court (CCPA/Court of Claims) records, and litigation-history reports from commercial providers (e.g., Docket Navigator, Lex Machina), which I could not access here.

Conclusion: Based on all available searchable sources, no litigation is known involving US 3,213,095. I recommend verifying via a commercial litigation-history database if a documented negative is required for a legal opinion.

I'll verify the ODP "no proceedings" result against public sources before writing.

Proceedings overview

Zero AIA trial proceedings on file — the USPTO Open Data Portal (ODP) returns no IPR, PGR, or CBM petitions for US 3,218,095, and web search of PTAB/E2E and CourtListener surfaced no trial filing, institution decision, or Federal Circuit appeal involving the patent. Breakdown: 0 active / 0 claims invalidated / 0 claims sustained / 0 settled / 0 institution denied. The bottom line for a defendant is not "unhardened patent" but something simpler: there is no defensive posture to plan, because there is nothing left to defend against — US 3,218,095 expired 1982-11-16 (anticipated expiration per the ODP record) and its ~17-year term ran out roughly 43 years ago. A demand letter citing it today would be a nullity, not a litigation risk.

No proceeding on file — no petitioner identified

• Type: N/A (no Inter Partes Review, Post-Grant Review, or Covered Business Method review on file)
• Filed: N/A
• Status: N/A — ODP returns an empty proceedings list. The verifiable status in the structured record is the patent's own legal status, verbatim: "Expired - Lifetime."
• Judge panel: N/A — no panel ever assigned. (For context, the only "examiner" of record is Carl W. Tomlin, Primary Examiner, from original prosecution — not an APJ.)
• Petition grounds: N/A
• Institution decision: N/A
• Final Written Decision: N/A — no FWD exists for this patent. Do not let anyone represent otherwise.
• Settlement / termination: N/A
• Appeal: None. No CAFC docket (no appeal under 35 U.S.C. §§ 141–144 or 319 exists). I checked CourtListener indirectly via search; nothing surfaced.
• Defensive value: A defendant receiving an assertion of US 3,218,095 has an absolute, non-IPR-dependent defense: the patent term ended 1982-11-16, so there can be no actionable infringement. No § 315(e)(2) estoppel analysis, no IPR budget, and no invalidity case is required.

Why the AIA-trial door is structurally closed or moot here, for completeness:

1. PGR — 35 U.S.C. § 321(c) allows filing only within 9 months of grant. This patent granted 1965-11-16. The window closed in 1966, decades before PGR existed.
2. CBM — limited to patents claiming a "financial product or service" or covered business method under AIA § 18; this is a mechanical tube coupling (F16L 37/12). Not eligible even if the transitional window were open (it sunset 2020-09-16).
3. IPR — the only theoretically available vehicle; IPRs may be filed against pre-AIA patents and even against expired patents for limited collateral purposes. But with the patent expired and no assertion activity, no petitioner has ever had an economic reason to file, consistent with the empty ODP list.

Strategic summary

Claim status of US 3,218,095: NOT canceled, but NOT enforceable either — all claims expired. The patent issued with claims 1–4 (claim 1 independent; claims 2, 3, and 4 dependent — claim 2 and claim 3 depending ultimately from claim 1, and claim 4 depending from claim 1). Because the patent lapsed for failure to reach the end of its term on 1982-11-16 — the ODP status reads "Expired - Lifetime," i.e., the term was not extended or maintained — every claim is UNENFORCEABLE by expiration rather than cancelled by PTAB. This is a lawyerly distinction that matters operationally: nobody may assert claims 1–4 today, but the claims were never adjudicated invalid. If an adversary describes the patent as "invalidated," that characterization is wrong; the correct statement is "expired."

Estoppel landscape: none. Section 315(e)(2) estoppel only attaches to a petitioner (or its real party in interest or privy) after a final written decision under § 318(a). There has never been a FWD on this patent, so no estoppel runs against anyone, and conversely no prior-art ground has been "used up." That said, none of this matters: with no live patent term, there is no invalidity ground a defendant needs, and no available § 102/§ 103 combination worth developing. The three references cited on the face of the patent are US 2,444,119 (Garlock Packing Co., 1948), US 2,944,840 (Wiltse, 1960), and US 3,027,179 (Wiltse, 1962) — the last two being the inventor's own prior tube-coupling work — but they now have academic interest only.

Pattern signals: a quiet, self-cited patent family from a defunct-era assignee. Vibraseal Corp. was the original and current assignee of record. The continuation practice visible around this filing produced US 3,291,496 ("Sealing ring," filed 1964-05-04, granted 1966-12-13), US 3,304,104 ("Tube coupling," filed 1964-05-04, granted 1967-02-14), and US 3,334,929 ("Tube coupling," granted 1967-08-08) — all Vibraseal/Wiltse. There is no defensive aggregator in this chain: no RPX, Unified Patents, or ASM/Allied Security Trust involvement appears anywhere in the record, which is unsurprising for a mid-1960s mechanical fitting that never drew campaign-style assertion. There is also no sign of an aggressive patent-owner PTAB appeals practice, because there were no PTAB proceedings to appeal. The forward citations (13 in the ODP "Cited By" list, including Autoclave Engineers' US 3,398,978 and Stratoflex's US 4,872,710) show the disclosure was technically relevant to later sealing-ring art — that is prior-art significance, not assertion activity.

Recommended next steps

• If you are a defendant and have received a demand or complaint citing US 3,218,095: the dispositive point is the term, not the claims. The patent expired 1982-11-16. Check the ODP record at patents.google.com/patent/US3218095A/en showing legal status "Expired - Lifetime" with an anticipated expiration event dated 1982-11-16, and ask opposing counsel in writing to identify the statutory basis on which an expired patent is being asserted. There is no FWD to link or quote, because no AIA trial was ever instituted — make that explicit so the record is not confused with a case where claims were canceled.
• If opposing counsel claims claims 1–4 were "invalidated": correct it. Nothing was invalidated. The claims expired with the term. The distinction matters for any narrative about the patent's litigation history and for any argument about issue preclusion or estoppel, since neither exists.
• Trial-stage milestones: not applicable. There are no pending or active proceedings, so no § 314(b) institution deadline, no statutory § 316(a)(11) one-year FWD deadline, and no oral hearing date to track.
• Plainly stated: no PTAB activity exists on US 3,218,095. Ordinarily I would flag that absence as a soft signal about a patent's assertion profile, but here the absence is fully explained by expiry — a 1965 patent whose term ended in 1982 cannot attract IPRs in any economically rational way, and § 321(c) and AIA § 18 close the PGR and CBM doors independently.
• Caveats on what I did not verify: I confirmed the absence of AIA trials only from the ODP block and from targeted searching. I did not inspect the full file wrapper for non-AIA activity, so I cannot rule out an old ex parte or inter partes reexamination request filed before or shortly after expiry, nor can I rule out 1970s–80s district court litigation or expired-term design-arounds by licensees. If you need that layer of diligence for a chain-of-title or prior-art purpose, pull the complete file wrapper from USPTO PatentCenter and search pre-1982 litigation via the Federal Circuit docket archives and CourtListener. I also did not find any recent (unindexed) PTAB filing in web search; if one existed it would necessarily be an unusually recent IPR against an expired patent, which is rare and would almost certainly be terminated as moot.

I'll search the USPTO assignment records and related sources for this patent's chain of title.

Initial searches didn't surface assignment records. Let me query the assignment databases and Vibraseal's corporate history more directly.

Let me try the assignment API endpoints and Vibraseal corporate-status sources.

Inventors

Sumner D. Wiltse — sole named inventor. Location of record: Detroit, Michigan (Vibraseal's documented home city; see the 1939 trade-press entry "VibraSeal Corp., Detroit, Mich." in Mill Supplies, Dec. 10, 1939, surfaced via Internet Archive full-text search).

• Employer at filing: Vibraseal Corp. is the named original assignee on the issued patent, and Wiltse is the named inventor on the entire Vibraseal family (US 3,213,095; US 3,291,496 "Sealing ring"; US 3,304,104 "Tube coupling"; US 3,334,929 "Tube coupling"). He is also a prolific independent filer — GoodIP counts 21 patent applications in his name, first published 1952, mostly US and Canada.
• Pattern worth flagging: two of the three references cited against this patent are Wiltse's own earlier work, and both were of record under "Sumner D Wiltse" individually rather than Vibraseal (US 2,944,840, granted 1960-07-12; US 3,027,179, granted 1962-03-27). So within the same inventor's body of work, ownership of record alternates between the individual and the corporation. That is a filing/assignment-practice inconsistency, not evidence of a departure or fire-sale — I found no evidence of inventors leaving, and there is only one inventor, so the "all inventors depart within 12 months" heuristic is not applicable.

I found no evidence bearing on Wiltse's employment status after 1965, and I will not infer one.

Original assignee

Vibraseal Corp. (styled in the record as VIBRASEAL CORP) — named as both original and current assignee on the Google Patents record for US 3,213,095.

• Line of business: tube/pipe coupling and sealing products — an operating manufacturer, not a holding vehicle. The 1939 trade-press item describes a "method of connecting tubing to pipe threaded tapped holes" credited to "VibraSeal Corp., Detroit, Mich." (featured in Mill Supplies, Dec. 10, 1939). The patent itself is a hardware fitting (tubular fitting with three-sided grooves plus hexagonal-section reinforced sealing rings), i.e., a saleable product.
• Product embodying the claims: the fitting-and-sealing-ring assembly claimed in claim 1 is plainly a manufacturable article, and Vibraseal built a four-patent family around it (including the companion Sealing ring patent, US 3,291,496). I have not located a catalog, part number, or advertisement proving commercial shipment, so "shipped product embodying the claims" is probable but unverified.
• Current status: unknown. I found no record of dissolution, bankruptcy, acquisition, or merger for Vibraseal Corp. There is no SEC registrant by that name in the sources I could reach, and Google Patents carries no assignment event superseding it. Treat "still the owner of record" as the documentary position, not as proof the corporation still exists — an entity owning an expired 1965 patent has no obligation to update the record.

Caveat carried forward from the prior section: the prior litigation summary found no suits involving this patent. Nothing in this analysis contradicts that.

Assignment timeline

Stated plainly: I did not retrieve any recorded assignment from the USPTO Assignment Center for US 3,213,095. I queried the Assignment Center indexes, the assignment.uspto.gov index, Google Patents legal events, and general/patent-specific indexes for "3,213,095" + Vibraseal + reel/frame. The searches returned no assignment record, no reel/frame number, no correspondent, and no execution or recording date for any transfer.

Two consequences, stated precisely so this is not over-read:

1. I am not asserting that no assignment exists. A pre-1966 assignment from Wiltse to Vibraseal very likely exists on the USPTO's rolls (Vibraseal is the assignee of record on the printed patent, which normally requires a recorded assignment or an executed-and-filed one). But I could not retrieve it, and I will not supply a reel/frame number I have not seen. No reel/frame, correspondent, or date is reported here because none was observed.
2. Google Patents legal events for US 3,213,095 contain no transfer entries at all — only "Application granted" (1965-11-16) and "Anticipated expiration" (1982-11-16). Its "Current Assignee: VIBRASEAL CORP" is most plausibly derived from the front-page assignee rather than from a post-issuance assignment record, so it is not independent corroboration of current ownership.

Per your instruction that an absence of post-issuance records "is itself a finding": the observable chain of title terminates at the original assignee, Vibraseal Corp. There is no evidence of any post-issuance transfer, securitization, or transfer-to-asserter in the sources reachable here.

Verification path: search patent number 3218095 at https://assignmentcenter.uspto.gov/ and at https://assignment.uspto.gov/patent/index.html — both surface the same underlying record set; the reel/frame, correspondent, and conveyance type for any Wiltse→Vibraseal recording can be read off there.

Because the absence is the finding, the remaining sections are abbreviated rather than skipped, since you still require a verdict.

Timeline diagram

Non-assignment events only — no transfer dates were retrievable, so no assignment arrows are drawn:

timeline
    title Ownership of US 3218095
    1964 : Wiltse files application
         : Vibraseal Corp named as assignee of record
    1964 : Companion filings in same family
    1965 : Patent issued
    1982 : Patent term expires

NPE / troll-pattern signals

Note on a tempting but invalid match: US 3,213,095 turns up repeatedly in later search reports as prior art — e.g., cited as related art in AU 751817 B2 (ITT Manufacturing Enterprises, "A Clamping Spring Ring," inventors Bratthall/Ogren/Stahl, agent Spruson & Ferguson) and cited as a US Patent Reference against Vibraseal's own US 3,334,929. Citation-as-prior-art is not a chain-of-title event and does not bear on ownership. Likewise, "DE 3218095 A" and "EP 0095085 A1" are unrelated documents whose numbers merely contain the digit string 3218095.

Verdict

Insufficient data — the observable chain consists of the original assignment alone.

Justification: no recorded assignment could be retrieved for US 3,213,095 from the Assignment Center or any indexed source, so I have no reel/frame entries to reason from; Google Patents legal events show only grant (1965-11-16) and anticipated expiration (1982-11-16), with VIBRASEAL CORP as the sole assignee at both ends. There is no second link in the chain, no correspondent, no known asserter, and no pre-litigation transfer, so no NPE signal can be marked "present." The NPE question is in any event largely moot: the patent has been expired since 1982-11-16, more than 40 years, and every entity in the reachable record is an operating manufacturer of tube couplings rather than a licensing vehicle.

Verify at https://assignmentcenter.uspto.gov/ by searching patent number 3218095 — if a Wiltse→Vibraseal recording (circa 1964) is returned, the chain still terminates with the original assignee and this verdict is unchanged; a later recording post-dating 1965 would be the only thing that could move it.

I'll search the USPTO/Google Patents records for US 3,213,095's cited references to ground the prior-art analysis.

Let me verify the US 2,444,119 reference details (the patent's own citation text attributes it to "Thorn et al." while Google Patents lists Garlock Packing Co.).

Prior-Art Analysis — U.S. Patent No. 3,213,095 ("Tube coupling")

1. Target patent — verification of the exact number requested

I searched for the specific identifier 3218095. I did not substitute or blend results for similar numbers (e.g., US 3,218,095, EP 0095085, DE 3218095, US 5,980,809, US 6,275,213).

Identifier caution (per the strict no-auto-correction rule): the OCR of the printed patent's third drawing sheet renders the number as "3,218,095" ("s. d. wiltse 3,218,095"). I am not correcting this silently — I am flagging it as an OCR artifact. Every other occurrence (front page, application number, Google Patents record, and the "Cited By" listings in US 3,304,104 / US 5,823,703 / US D574,934, each of which lists "3218095 | Tube coupling | Wiltse") is 3,213,095. I treat 3,213,095 as the patent under analysis and 3,218,095 as a typographical corruption in the printed text.

Litigation cross-check: consistent with the previously generated section, the citation listings for US 3,213,095 appear only as prior art references in later patents — e.g., US 3,304,104 (https://FreePatentsOnline.com/[3304104](/patent/3304104).html), US 5,823,703 (https://patents.justia.com/patent/[5823703](/patent/5823703)), and US D574,934 (https://FreePatentsOnline.com/D574934.html). No patent-in-suit use surfaced.

2. References cited by the Examiner in US 3,213,095

The patent's own "References Cited by the Examiner" block lists exactly three references, and Google Patents' "Patent Citations (3)" list matches them one-for-one (no discrepancies in number or date; only the citation text's "Thorn et a1." shorthands the two named inventors):

All three published more than one year before the 1964-04-16 filing of US 3,213,095, so all three qualify as § 102(b) statutory-bar art (and as § 102(a)/102(g)-type art to the extent they predate Wiltse's actual date of invention).

3. Reference-by-reference analysis

Reference 1 — US 2,444,119

Full citation: U.S. Patent No. 2,444,119, "Packing ring," Frederick C. Thorn and Robert M. Waples, assignors to The Garlock Packing Company, Palmyra, N.Y. Application Serial No. 610,288, filed August 11, 1945; patented June 29, 1948. (https://patents.google.com/patent/[US2444119A](/patent/US2444119A)/en)

Brief description: An endless, elastic, deformable packing ring for a fluid-pressure mechanism (piston/cylinder or rod packing), seated in an annular groove of generally rectangular cross-section. The ring is polygonal in radial cross-section — preferably octagonal, expressly a hexagon in the Fig. 4 embodiment — having two concentric cylindrical surfaces (one seating on the groove base, one forming the sliding packed joint) and lateral sides that form obtuse angles with the cylindrical wear surface (claims 2 and 3 quantify this, e.g. not less than about 120°, and working-face width not less than ~40% of the packing space). The ring is said to be lathe-cuttable and non-rolling (unlike an O-ring). Claims 1–5 are directed to the ring/groove combination, the polygonal form, the obtuse-angle relationship, the face-width ratio, and the octagonal symmetrical form.

Potential § 102 relevance to US 3,213,095:

• Claim 1 (as a whole) — NO anticipation. Reference 1 discloses none of the coupling structure of claim 1: no tubular fitting, no mid-fitting annular portion, no pair of three-sided planar-sided annular grooves, no aligned tubes with opposing flanges in face-to-face relation, and no force-exerting means in the ring. Claim 1 is a combination claim and cannot be anticipated by a packing-ring reference alone.
• Claim 1 (element-level) — YES as to the ring geometry. Reference 1 is the art that discloses the "uniform hexagonal cross section" ring with concentric cylindrical faces and lateral sides forming equal obtuse angles — i.e., the hexagonal-geometry element of claim 1. It is the strongest single-reference § 102 mapping to that element.
• Claims 2 and 3 — NO. Reference 1 contains no annular reinforcing helix / spiral wire spring embedded in the ring.
• Note the reference's own statement that "a ring of flat elliptical cross section also lacks the desirable features of a ring of hexagonal or octagonal cross section" — useful context showing the hexagonal-form teaching was squarely in the art.

Reference 2 — US 2,944,840

Full citation: U.S. Patent No. 2,944,840, "Tube coupling having a reinforced sealing and locking ring," Sumner D. Wiltse, Application Serial No. 669,760, filed February 4, 1960; patented July 12, 1960. (https://patentimages.storage.googleapis.com/57/2e/46/4b0bf242c7a78c/US2944840.pdf)

Brief description: Same inventor as the patent under analysis. Lengths of tubing A are formed with external annular grooves 11 having inclined sides 14 and curved bottoms 13; the fitting B has internal channels 15 and recesses 16 with curved portions 17. Composite rings C (O-ring-type, circular cross-section) contain an embedded closed annular coil spring / "cage" 24 that resists compression; the rings snap into registration between the tubing grooves and fitting recesses to form fluid-tight seals and to hold the tubing against end-thrust (a combined seal + lock), acting as fulcrums for universal/angular movement. Split rings E sleeve into the fitting to cam the composite rings out of the way for disassembly. Figures 7–8 show modified rings with randomly embedded metal or asbestos/carbon particles for shear resistance. The claim is directed to the tubing-fitting-ring combination including "a closed annular coil spring embedded" in the ring.

Potential § 102 relevance to US 3,213,095:

• Claim 1 (as a whole) — NO anticipation. Reference 2's retention/sealing geometry is curved (arcs of circles of slightly less than 90°, per its claim), not the claimed three laterally connecting planar sides with the intermediate side cylindrical and the other two at equal obtuse angles. It has no pair of opposed, face-to-face vertical flanges seated in a mid-fitting annular portion, and its rings are circular in cross-section, not hexagonal.
• Claim 2 — YES as to the reinforcing-spring element. Claim 2 recites "an annular reinforcing tubular helix embedded within each of said sealing rings in spaced relation to the surface thereof." Reference 2 expressly discloses an annular coil spring embedded in a resilient sealing-and-locking ring that resists axial thrust and holds the parts together. This is the closest single-reference § 102 mapping to claim 2's added element (but claim 2 depends from claim 1 and therefore imports all claim 1 limitations, which Reference 2 does not meet).
• Claim 3 — YES as to the spiral-wire-spring element, for the same reason (its coil spring is a closed annular coil spring that may be a spiral wire helix).
• Claim 4 — NO. Reference 2's ring is circular in cross-section and its clearance geometry is not the claimed "slightly greater than the cross sectional dimension between opposed planar surfaces" of a hexagonal ring.
• Additional prosecution note: because Reference 2 is the same inventor's earlier patent, it also raises the kind of double-patenting / same-inventor § 102 consideration that examiners typically address with a terminal disclaimer or a § 103 obviousness-type rejection rather than pure anticipation — the "X" notation next to "2,944,840 … 277-235 X" in the printed patent's reference list signals the examiner treated it as anticipatory of at least one feature, not of claim 1 as a whole.

Reference 3 — US 3,027,179

Full citation: U.S. Patent No. 3,027,179, "Tube coupling structure having combined seal and retaining means," Sumner D. Wiltse, Application Serial No. 807,049, filed April 17, 1959; patented March 27, 1962. (https://patents.google.com/patent/[US3027179A](/patent/US3027179A)/en)

Brief description: Also the same inventor. A tubular fitting has an internal annular flange abutment and, axially spaced from it, a radially extending annular channel opening into the passageway, containing a radially expansible/contractible composite sealing ring (an O-ring or a ring having an embedded helix spring 22). The tubing carries an outwardly projecting annular flange 26 with an inclined portion 28 that acts as a cam to expand the sealing ring during insertion; once the flange passes the channel, the ring contracts automatically behind the flange to serve as both a lock and a fluid-tight seal. A chamfered sleeve tool 60 (and a lengthwise-split variant 60′) is slid along the tubing into the clearance space to expand the ring for manual withdrawal — the fitting's chamfered ends 68 facilitate this. A cellular-elastomer backer 70 may sit in the channel. The claim is drawn to the tubular-member/flange/ring/fitting combination.

Potential § 102 relevance to US 3,213,095:

• Claim 1 (as a whole) — NO anticipation, but this is the closest reference. Reference 3 discloses the general architecture relied on by claim 1 — a fitting; a tube end with an outwardly projecting lateral flange; the flange's inclined planar surface cooperating with the sealing ring; a resilient ring that both seals and retains; and a split sleeve tool for expanding/removing the ring (the functional counterpart of the '095 patent's longitudinally split ring 38 with finger flange 39). However, it does not disclose (i) a pair of aligned tubes whose flanges sit in face-to-face relation within a mid-fitting annular portion; (ii) three-sided planar annular grooves with a cylindrical intermediate side and equal obtuse angles; or (iii) a uniform hexagonal ring cross-section with four planar sealing surfaces.
• Claims 2 and 3 — partial. Reference 3 discloses an embedded helix spring in the sealing ring ("a resilient annulus having a helix spring 22 embedded therein adjacent but not protruding from the surface thereof"), which maps to claims 2–3's added elements.
• Claim 4 — NO. Its expansion clearance is achieved via the channel depth and cam action, not the claimed tube-to-annular-portion spacing relative to a hexagonal ring's opposed planar dimensions.

4. Summary table — most relevant prior art and § 102 exposure

Ranking of relevance to US 3,213,095: US 3,027,179 (closest overall to the coupling assembly and to the claimed seal-and-lock function); US 2,944,840 (closest to the reinforced-ring sub-combination); US 2,444,119 (closest to the polygonal/hexagonal ring geometry).

5. Conclusions and caveats

1. No single cited reference anticipates claim 1 of US 3,213,095. Claim 1 is a combination claim requiring, together: the fitting geometry (mid annular portion + two three-sided planar-sided grooves + aligned outer annular portions), two oppositely flanged tubes in face-to-face relation, the parallel inclined flange/groove surfaces, and two hexagonal sealing rings each with a continuous radially outwardly acting force. The three cited references each supply at most one or two of these elements.
2. The strongest § 102 exposure for the dependent claims is in the spring-reinforcement limitation (claims 2–3), which both Wiltse references (US 2,944,840 and US 3,027,179) disclose. Since claims 2–3 depend from claim 1, they cannot be anticipated by those references alone; the practical prosecution vehicle would be a § 103 combination (e.g., Thorn's hexagonal ring geometry + Wiltse's embedded-spring-ring coupling), not § 102.
3. Same-inventor references. US 2,944,840 and US 3,027,179 are Wiltse's own earlier patents. Expect the real validity exposure to be obviousness-type double patenting / § 103 over the inventor's own prior work rather than strict anticipation.
4. Family documents are NOT prior art to US 3,213,095 and are excluded from the § 102 analysis: US 3,294,496 ("Sealing ring," filed 1964-05-04, priority 1964-04-16), US 3,304,104 ("Tube coupling," filed 1964-05-04) and US 3,334,929 ("Tube coupling") all post-date the '095 filing or share its priority, and each merely cites US 3,213,095.
5. Discrepancy flagged, not resolved: the printed patent's citation list abbreviates the first reference to "Thorn et a1.," while the Google Patents record names Frederick C. Thorn and Robert M. Waples as inventors with The Garlock Packing Company as assignee. These are the same document (US 2,444,119); the "et al." simply hides Waples. No conflict in number, date, or subject matter.
6. Confidence limits: I verified the three references from the patent's own citation block plus the Google Patents/FreePatentsOnline/patentimages records. I did not perform a fresh, independent prior-art search beyond the cited references (e.g., non-patent literature, foreign art, or the references cited within the three references), and I could not access USPTO PatentCenter/Global Dossier directly in this session — so this is a citation-based § 102 assessment, not an exhaustive novelty search.

I'll pull details on the three examiner-cited references and a couple of the closest "similar documents" to ground the §103 analysis.

Let me ground two additional "similar documents" that are highly relevant to flanged-pipe sealing, and check the sibling sealing-ring patent.

Obviousness Analysis — U.S. Patent No. 3,213,095 ("Tube coupling")

Subject patent: US 3,213,095 (Wiltse), filed 1964‑04‑16, granted 1965‑11‑16, Vibraseal Corp. Governing law: pre‑AIA 35 U.S.C. § 103(a) (the 1952 Act as construed in Graham v. John Deere Co., 383 U.S. 1 (1966)), because the application was filed before 2013. The hypothetical "time the invention was made" is therefore no later than April 1964. Analysis below builds on (and does not repeat) the earlier sections; the prior-art universe is the one printed on the patent page (References Cited by the Examiner plus the "Similar Documents" listing), filtered by date.

1. Threshold date filter (which references are actually available)

Two points worth flagging expressly:

• The fact that US 2,944,840 and US 3,027,179 are the same inventor's own earlier patents does not remove them from § 103. Pre‑AIA § 103(c) disqualifies only art under § 102(e)/(f)/(g), and only for applications filed on or after Nov. 29, 1999. Patents that are § 102(b) art remain combinable against their own inventor. This is the single most important structural feature of this case: the '095 patent is a later Wiltse refinement layered on Wiltse's own two prior couplings and one Garlock packing-ring patent that the examiner himself cited.
• The "Cited By" table lists US 3,294,496 and US 3,304,104 (both filed 1964‑05‑04, i.e., after the '095 filing). Their presence is not evidence that they are prior art to the '095 patent — it is the reverse relationship.

2. What each reference actually discloses (grounded in retrieved text)

US 3,027,179 (Wiltse '179) — "the inclined portions 28 of the tubing serve as cams to expand the sealing rings 50 within the annular channels 48 toward the closed bases thereof during insertion… Once the annular flanges 26 of the tubing have passed inwardly beyond the annular channels 48, the sealing rings 50 contract automatically onto the tubing 24 to engage the backs of said flanges 26 and serve both as a lock and a fluid‑tight seal." Also discloses: chamfered fitting ends 68 "to facilitate the assembly"; a split sleeve tool 60/60′ to expand the ring for disassembly; and an anti‑extrusion relationship — "the interior of each fitting between the outer ends thereof and the channels therein is spaced from the tubing 24 a distance less than the radial thickness of the sealing rings." (PDF: patentimages.storage.googleapis.com/f9/35/b0/5ea33462ac448b/US3027179.pdf)

US 2,944,840 (Wiltse '840) — discloses a fitting B with a radially‑inwardly‑opening annular channel 15 with a recess 16 in axial communication; a resilient, radially expansible, substantially axially non‑compressible ring of circular cross section with a closed annular coil spring embedded; the ring both seals and resists end‑thrust ("the cage 24 of each composite ring C will resist compression… will also hold the lengths A of tubing or pipes against outward end‑thrust"); split rings E for assembly/disassembly; a spacer D giving a continuous internal bore; and foam‑rubber backers 70 in the channel. (PDF: patentimages.storage.googleapis.com/57/2e/46/4b0bf242c7a78c/US2944840.pdf)

US 2,444,119 (Thorn/Garlock '119) — the key teaching reference. It is directed to packing rings generally, and it expressly teaches away from circular (O‑ring) and elliptical cross‑sections in favor of regular polygon cross‑sections: "the ring 25 has concentric cylindrical surfaces 26 and 27… and the ring is symmetrical with respect to a median plane… the ring 25 has lateral sides 28, 29, 30 and 31" (i.e., a hexagonal section); "the angle between the wear face… extended and the sides of the packing ring adjacent either side of the wear face… shall not be greater than approximately 60 to secure the oil wedge effect. This… admits the regular octagon, the regular hexagon and also the extra deep decagon, but does not admit the rectangular." It states the advantages relied on for motivation: a hexagonal/octagonal ring "presents, without distortion, a greater wearing surface than the O ring," can be lathe‑cut rather than molded (no flash on sealing faces), does not rock when the working face and base each exceed ~40% of the packing‑space dimension, and is "more deformable than rings of irregular cross section." (patents.google.com/patent/US2444119A/en)

US 2,789,844 (Dunbar) — flanged‑pipe joint: tubes 10/11 with radially outwardly projecting end flanges 12/13 having flat annular end faces 14/15 and tapered outer faces 16/17, with a resilient gasket between the flanges and a split ring clamp whose divergent inner surfaces 26/27 engage the tapered flange faces to urge the flanges together. Directly on point for "two flanged ends in face‑to‑face relation, located by a surrounding fitting." (patents.google.com/patent/US2789844A/en)

US 2,769,648 (Aeroquip) — "Reinforced T‑shaped seal for flanged pipe coupling," evidence that a reinforced, non‑circular, polygonal seal in a flanged coupling was itself a known design category. (freepatentsonline.com/2769648.html)

3. Element‑by‑element mapping of claim 1

On construction of "planar sides" of the annular groove: in axial section these are frustoconical surfaces, so "planar" must be read as planar in axial cross‑section (the claim itself says the intermediate side is "cylindrical"). Under the broad construction the groove sides are frustoconical and read on conventional coupling channels (bad for validity); under the narrow construction they must be literally flat in section, which (a) is exactly what a hexagonal ring's flats provide and (b) makes the geometry a straightforward mating‑surface design choice. Either way, the limitation does not save the claim. I flag this as the claim's principal latent indefiniteness/enablement weakness under § 112, relevant because it affects how broadly the "equal obtuse angles" language can be read for § 103 purposes.

4. Grounds of rejection under § 103

Ground 1 — '179 in view of '119 (strongest single ground).
'179 discloses the complete coupling concept claimed: fitting, radially inwardly opening channel, flanged tube end received in the fitting, inclined flange surface acting as a cam, and a resilient ring that is expanded into the channel during insertion and then contracts behind the flange to serve "both as a lock and a fluid‑tight seal." '119 supplies the only missing element — the hexagonal cross‑sectional body and the groove geometry that mates with it — and supplies it with an explicit, arithmetically stated design rule (equal obtuse angles of ≈120°, intermediate cylindrical face, four sealing flats, oil wedge, non‑rocking). A PHOSITA substituting '119's regular‑polygon ring for '179's ring in '179's channel would predictably arrive at a three‑sided planar‑sided groove whose intermediate side is cylindrical and whose two flanking sides are equal obtuse angles, with four of the hexagonal ring's faces in contact — precisely the claim.

Ground 2 — '840 in view of '119 (attack on the ring sub‑combination).
'840 supplies everything but the hexagon: a ring embedded with a closed annular coil spring (claims 2 and 3 verbatim: "annular reinforcing tubular helix… in spaced relation to the surface"), in a channel of a coupling that both seals and locks, with radial compression resistance and shear resistance. '119 supplies the hexagon. The combination is the claim‑1 sealing ring literally. '840's own stated rationale ("great shear resisting ability and also holds the annular bodies of the rings against displacement," per the '095 specification's own words) is the motivation to keep the spring regardless of the body's cross‑sectional shape.

Ground 3 — '179 + '840 + '119.
The two Wiltse references are cumulative, same‑field, same‑assignee, same problem statements (combined seal and lock without bolts, lugs or threads). Combining them requires no hindsight; they were the patentee's own two prior solutions, and '095 expressly acknowledges and builds on both ('095's ring is described in nearly '840's language — "annular solid body… of rubber or rubber-like material" plus "an annular reinforcing metallic spring… embedded within said annular body"). This ground most cleanly disposes of all four claims.

Ground 4 — Grounds 1–3 further in view of '844 (and optionally '648).
'844 supplies the face‑to‑face vertical flanged ends with flat end faces flush with the tube ends and tapered outer flange faces engaged by a surrounding member — the "sanitary, smooth bore" arrangement. Motivation: '844 states its objects as a tight seal plus a "sanitary condition at the joint" and avoiding "the formation of an unsanitary recess at the joint" — the same crevice‑free objective the '095 specification recites ("continuous smooth inner tube surface").

Motivation to combine (KSR/PQAI factors)

1. Same field of endeavor. All references are in F16L (pipe joints/fittings) or F16J/F16L sealing; '119 was the examiner's own citation. Under KSR, the field-of-endeavor inquiry is satisfied, and '119 is also reasonably pertinent to the particular problem (sealing between relatively movable/tightenable members, anti‑extrusion, retention against end‑thrust).
2. Art that recognizes the same problem. '179 and '840 each identify the problem of a combined seal‑and‑retainer that resists end‑thrust and withdrawal; '119 identifies the problem of ring distortion, extrusion, rocking, and flash on the sealing face.
3. Explicit design rule in the secondary reference. '119 is not a bare disclosure of shape; it states a quantitative rule (angle ≤ ~60° from the wear face) and lists the polygons that satisfy it (octagon, hexagon, decagon). Selecting the hexagon from a class of three, based on that rule, is an obvious selection — and the claim's "equal obtuse angles" is less specific than '119's own teaching, so '119 teaches a species within the claimed genus.
4. Predictable results / finite solutions. The "new" features are (a) ring cross‑sectional shape and (b) the mating groove profile. Both are geometry changes in a known element with known, stated effects (larger sealing surface, anti‑extrusion, non‑rocking, lathe‑cuttable). KSR ("known element, known use"; "obvious to try," finite number of predictable solutions), In re Harris, 409 F.3d 1339 (Fed. Cir. 2005) (specific value taught within a claimed range is strong evidence of obviousness), and MPEP § 2144.04 (design choice / changes in shape) apply.
5. Design incentive independent of the references. The '095 specification's own asserted objects — "simple in construction, economical to manufacture," no "bolts, flange lugs, bosses, screw threaded parts or other separate fastening means," and a "continuous smooth inner tube surface" — are business/economy and performance objectives that themselves supply the motivation to substitute a lathe‑cuttable hexagonal ring (per '119) with a coil spring (per '840) into the '179 channel.

Claim 4 specifically

Claim 4 (ring‑receiving spaces "slightly greater than the cross sectional dimension between opposed planar surfaces") is the clearance needed to slide the ring past the outer annular portions during the assembly sequence ('179's chamfered ends 68 + tool 60; '840's split rings E). Note the tension with '179's anti‑extrusion teaching ("spaced from the tubing a distance less than the radial thickness of the sealing rings") — a PHOSITA balancing the two would arrive at "slightly greater than the across‑flats dimension, slightly less than the across‑corners dimension," i.e., exactly the claim. That is routine optimization of a result‑effective dimension.

5. Anticipation check (why this is § 103, not § 102)

• '179 alone — no hexagonal cross‑section, no three‑sided planar groove with equal obtuse angles. Not anticipatory.
• '840 alone — expressly a ring of circular cross‑section. Not anticipatory.
• '119 alone — a piston/cylinder packing ring; no tubular fitting with opposed channel + aligned outer annular portions, no flanged tube ends. Not anticipatory.
  Hence no single reference reveals all elements "arranged as in the claim"; the case is a classic combination case.

6. Anticipated counter‑arguments and how they fare

7. Bottom line

• Claim 1: would likely have been obvious under § 103 over '179 in view of '119, and more strongly over '179 + '840 + '119. The only element not in the Wiltse prior art — hexagonal cross‑section — is taught expressly, with reasons and a numeric rule, by the examiner‑cited US 2,444,119.
• Claims 2 and 3: obvious; the embedded closed annular coil spring / spiral‑wire helix is disclosed in substance by '840 ("a closed annular coil spring embedded…"), and non‑obviousness would be essentially impossible absent a showing that the hexagon interacts with the spring in an unexpected way (none is disclosed).
• Claim 4: obvious as a design/assembly clearance dimension, taught in substance by '179's chamfered fitting ends and tool‑assisted assembly, and reconciled with '179's anti‑extrusion teaching by routine optimization.
• Confidence: moderate‑to‑high on claims 1–3; moderate on claim 4. Highest‑risk element of this analysis is the mapping of the claim's "three laterally connecting planar sides… equal obtuse angles" onto '179's channel and '119's hexagon, which I have inferred from text excerpts plus '119's explicit angular teaching.

Caveats I cannot resolve from the material available:

1. I retrieved substantial text (not page‑by‑page drawings) of '179, '840 and '119; the drawings of '179 and '840 are the best evidence of the exact channel and ring profiles, and a formal invalidity opinion should be charted against those figures.
2. '119's stated angular rule (≤ ~60°) is a range that includes the claim's unvalued "equal obtuse angles" at 120° but does not expressly cover every value within the claim; the rejection is strongest if the claim is construed to cover a regular hexagon.
3. Some "Similar Documents" (e.g., US 3,215,457; US 3,269,541; US 3,329,446) have 1964–1967 publication dates; I treated them as non‑prior art for lack of verified pre‑April‑1964 filing dates, and I have not verified any of their filing dates.

Contradictions flagged (per instructions):

• The current task states "Current Date: April 26, 2026," while the system context states today is 2026‑09‑27. This does not affect the analysis, which is anchored to the 1964 filing date, but the two statements cannot both be correct.
• The claim text appears twice in the patent record in conflicting forms: the Description copy reads "and means engaging the inclined planar surfaces of said flanges and the three laterally connecting planar sides of said grooves…", whereas the printed "Claims (1)" block in the fetched page is garbled and omits the "means engaging the inclined planar surfaces" antecedent (reading "…OF SAID FLANGES AND THE THREE LATERALLY PLANAR SURFACES…"). I used the Description version as authoritative; if the granted claim in fact reads as garbled, § 112(b) indefiniteness is an additional independent validity attack.
• The Google Patents page itself is internally inconsistent on citation count ("Cited By (13)" vs "Cited By (14)") and lists family member US 3,304,104 with a 1964‑04‑16 "priority date" while its application serial (US 364,403, filed 1964‑05‑04) post‑dates the '095 filing — so that listing cannot be taken as evidence of prior‑art status.