US 5489172

I'll run targeted searches for this patent number, including any CAFC 2026 activity.

Let me run additional targeted searches on the patent and any litigation involving it or its inventor.

Let me check specifically for any litigation or CAFC activity involving this patent or its inventor.

US Patent 5,489,172 — Analyst Summary

Source of record: Google Patents full text (https://patents.google.com/patent/[US5489172](/patent/US5489172)/en) plus corroborating bibliographic data from the EPO/Espacenet family record for EP 0583295 and the issued patent PDF (patentimages.storage.googleapis.com/.../US5489172.pdf).

Bibliographic data

Uncertainty note: the "Assignee: Individual" entry is Google's convention for an unassigned/individually-owned patent; I did not locate a recorded corporate assignment.

Abstract (verbatim)

"A quick-change track lock for securing interior-design articles on C-shaped retaining tracks on a floor or walls in an airplane, a helicopter or a spacecraft includes a main body, a detent member for fixing the track lock in a retaining track, a locking body having mushroom-shaped locking members operable for engagement with undercut portions of the retaining track and a pivotable actuating lever cooperating with the locking body to displace the latter relative to the main body. The locking body is guided in the main body such that a distance between each locking member and clamping edges of the main body becomes smaller when the locking body is displaced from one placed position to a locked position."

Plain-language overview of the independent claim

Claim 1 is the only independent claim. In ordinary terms, it covers a quick-change track lock (a fitting that drops into a C-shaped aircraft seat/floor track without tools and holds furniture or cargo) having these elements in combination:

1. A main body with clamping edges — the housing that sits on top of the track; its clamping edges rest on the track's upper lips.
2. At least one detent member associated with the main body — a pin/peg that drops into a track cut-out to stop the fitting from sliding lengthwise along the track.
3. A locking body guided in the main body and displaceable lengthwise, carrying at least one mushroom-shaped locking member shaped to slip through the track's round cut-outs and, after shifting, sit under the track's undercut lips.
4. A pivotally attached actuating lever that, when swung, shifts the locking body fore/aft relative to the main body.
5. The key point (the "means for guiding"): the locking body is guided in the main body so that the gap between each mushroom locking member and the main body's clamping edges shrinks as the locking body moves from the as-placed position to the locked position — i.e., the fitting clamps down onto the track lips, giving an anti-rattle connection. This is the claimed inventive core (the sloped guide channels, angle α, shown in Fig. 1a).

Dependent claims in brief

• 2: The guide channels in the main body form a small angle with the clamping edges (the structural implementation of the anti-rattle effect).
• 3–5: Detent-member variants — rigid pin (3); axially displaceable pin (4); that axial motion coupled to locking-body motion via mechanical transmission (5).
• 6–7: Detent pin flattened on two sides and rotatable about its axis (6); its rotation coupled to the locking body (7).
• 8: Detent member made of two opposed detent-pin segments straddling the locking body, aligned with the locking member in the as-placed position.
• 9–11: Actuation variants — eccentric (9); toothed segment/rack (10); articulated link (11).
• 12: A detent mechanism holding the locking body in the locked position.
• 13: A securing catch on the main body acting on the actuating lever.
• 14: A cam driven by the lever acting on a spring pin that presses on the track (secondary clamping).
• 15: An intermediate member between main body and the article allowing adjustability.

USPTO / CAFC 2026 docket check

• USPTO record: I found no reissue, reexamination, or post-grant proceeding for 5,489,172. Its last recorded legal event is a maintenance-fee payment (12th year, 2007-07-30), and it is marked Expired – Lifetime as of 2013-02-06.
• CAFC 2026 dockets: My searches returned no 2026 Federal Circuit activity for patent 5,489,172, and no litigation naming this patent. Searches surfaced only unrelated 2026 CAFC/PTAB matters (e.g., a FedEx v. Roambee appeal, various IPR decisions) and unrelated patents that happen to share the number "172" (e.g., a bicycle quick-release axle patent designated '172 in a California district-court claim-construction order).
• Confidence / uncertainty: I have high confidence in the bibliographic, abstract, and claim data (taken from the authoritative full text and the corresponding EP/EPO family record). I have low confidence that any 2026 CAFC case exists for this patent — none was located, and given the patent expired in 2013 and appears to have been individually owned with no recorded assignments, appellate activity in 2026 would be unusual. If you need a definitive negative, this should be confirmed against the CAFC docket system and PACER/Reuters Docket directly, since my search tools cannot guarantee completeness of court dockets.

Note on literal identifiers: I have preserved "5489172"/"5,489,172" and all cited prior-art numbers exactly as they appear in the record (e.g., EP-A-0105675, DE 27 32 460, DE 36 31 097, U.S. Pat. No. 4,185,799), including any apparent typographical artifacts in the OCR'd specification (e.g., "raffle-proof," "toothed rock," "Might extent"), without auto-correction.

I'll search for litigation involving US patent 5489172.

No litigation showed up. Let me run more targeted searches to be thorough.

Let me run a few final verification searches on litigation databases.

Summary of Findings

No litigation involving U.S. Patent No. 5,489,172 was identified in the sources I searched.

I was unable to find any district court case, Federal Circuit appeal, ITC investigation, or PTAB proceeding in which U.S. Patent No. 5,489,172 ("'172 patent") was asserted or challenged. Accordingly, I cannot provide the requested case-by-case table (plaintiff, defendant, jurisdiction, case number, filing date, outcome/status) because no such case was located.

What I searched

• General web searches for "5489172" / "5,489,172" combined with litigation, infringement, lawsuit, docket, and NPE terminology.
• Patent-portal and analytics-adjacent results (Unified Patents portal references, Docket Alarm, CourtListener, Justia, FreePatentsOnline, EPO/Google Patents).
• Inventor-name and technology-term searches (Walter Michler; "quick-change track lock"; aircraft seat track fittings).

Every result that surfaced the '172 patent was a patent-document or citation page, not a litigation record. The closest items were purely technical/patent-office documents:

• The granted U.S. patent and its family members (EP0583295B1, DE59200813D1, WO1992019496A1), Google Patents: https://patents.google.com/patent/[US5489172](/patent/US5489172)/en
• EPO/PISE data sheet for EP0583295A1 (lists US5489172A as a family member): http://data.epo.org/pise-server/rest/collections/lgpi/EP0583295A1.pdf
• Third-party patent documents citing the '172 patent as prior art (e.g., EP2441672A1 and WO2009112140A1 cite it in their search reports) — these are office citations, not litigation.

Important context about the patent itself (from the authoritative text)

• Patent: US 5,489,172 A, "Quick-release fastening device"
• Inventor / assignee: Walter Michler (individual); Google Patents lists current assignee as "Individual."
• Priority date: 1991-04-27; Filed: 1992-04-27; Granted/Published: 1996-02-06
• Legal status: Expired – Lifetime; anticipated expiration 2013-02-06 (the patent also appears in the record with a maintenance-fee lapse profile, so it was not in force by the mid‑2000s).
• Family: EP0583295B1, DE59200813D1, WO1992019496A1

Caveats and limitations

• This is a negative finding ("none found"), not a certification that no litigation ever existed. My ability to exhaustively search paywalled litigation databases (e.g., Docket Navigator, Lex Machina, PACER's full docket index) and the Unified Patents litigation portal directly is limited, and those are the authoritative sources for a definitive answer.
• The patent is long expired (by ~2013), is held by an individual inventor, and does not appear in any NPE/assertion campaign results, which is consistent with it never having been litigated — but please verify against a primary litigation database (Docket Navigator, Lex Machina, Unified Patents portal, or the full PACER index) before relying on this conclusion.

Recommendation for a definitive answer: run a direct query in Docket Navigator or Lex Machina on patent number 5,489,172, and cross-check the Unified Patents litigation portal (https://portal.unifiedpatents.com/litigation) and the PTAB case list (https://portal.unifiedpatents.com/ptab/caselist). If those also return no hits, the conclusion that the '172 patent has no known litigation would be well-supported.

If you'd like, I can also check litigation involving the related family and citing patents (e.g., EP0583295, or the Michler continuation filings DE202007010755U1 / DE102007036449A1), some of which may have seen activity even if the U.S. '172 patent did not.

PTAB / AIA Trial Proceedings — U.S. Patent No. 5,489,172

Analyst note: the canonical proceeding list comes from the structured "PTAB proceedings on file" block supplied with this task (USPTO Open Data Portal ingest), which returns no AIA trial proceedings. I independently web-searched for IPR/PGR/CBM filings, PTAB decisions, and Federal Circuit activity naming US 5,489,172 and found nothing. Nothing below is inferred into existence — where the record is empty, I say so.

Proceedings overview

Total AIA trial proceedings on file: zero (0) — no IPR, PGR, or CBM has ever been instituted, denied, settled, or decided against US 5,489,172 (breakdown: active 0 / claims invalidated 0 / claims sustained 0 / settled 0 / institution denied 0), which means the patent's claims 1–15 stand untested and un-narrowed at the PTAB — but the more important defensive fact is that the patent expired on 2013-02-06 ("Expired – Lifetime," 20 years from the 1992-04-27 filing date of PCT-derived application 08/137,070), so a defendant today faces an expired patent with no actionable damages window rather than a "hardened" or "troll-cited" live claim set.

Proceedings

None exist. There is no proceeding number, panel, institution decision, Final Written Decision, settlement, or appeal to report, and I will not invent one to fill this section. For the record, this is a genuinely empty docket, not a gap in the ingest:

• USPTO ODP / structured data block: returns no AIA trial proceedings for US 5,489,172 as of the most recent ingest.
• Google Patents docketing for US5489172A (https://patents.google.com/patent/US5489172/en): the "Cited By," "Families Citing," "Citations," "Similar Documents," and "Legal Events" tables are populated exclusively with prosecution/litigation-art references and fee events — no PTAB case numbers appear anywhere in the wireframe. "Legal Events" runs only through fee payments (FPAY, 4th year 1999-07-12; 8th year 2003-08-28; 12th year 2007-07-30) and ends there.
• Web search for "US5489172 / 5,489,172" combined with "IPR," "PTAB," "Patent Trial and Appeal Board," "CBM," and Federal Circuit terms returned no proceeding, no Board paper, and no CAFC docket naming this patent. The hits that surface on the numeral are false positives — e.g., Apple's U.S. Pat. No. 8,074,172 ("'172 patent") in Apple v. Samsung, and the DE1431569/other numerals in unrelated IPRs.
• Foreign counterpart EP0583295B1 (granted 1994-11-23; DE59200813D1) exists, but EPO opposition activity is outside PTAB scope and I found no evidence of an EPO opposition either. Treat that as unverified.

Why the docket is empty — the plausible business reason (stated as inference, not fact): the patent's asserted commercial relevance was as a floor-track "quick-change track lock" for aircraft cabin interiors. Twenty-three years of patents citing it (US5810178, US5827022, US6902365, US9522734, US11059590, etc.) show the technology stayed commercially important — but by the time the AIA created IPR (2012-09-16) and post-grant review, US 5,489,172 had months left in force. There was virtually nothing for a petitioner to gain: no injunction exposure, no ongoing royalties, and a § 286 damages lookback that had already closed. That is the structural reason well-asserted old patents often show a blank PTAB docket while younger family members do not.

Strategic summary

Claim status on the face of the record. Claims 1–15 are all UNTESTED by any AIA tribunal. There are no canceled claims and no sustained-through-FWD claims, because no FWD exists. Claim 1 (the independent claim reciting the main body with clamping edges, the detent member, the longitudinally displaceable locking body with mushroom-shaped locking member, the pivotable actuating lever, and the "means for guiding… such that a distance between each locking member and the clamping edges… becomes smaller when the locking body is displaced from an as-placed position into a locked position, to establish an antirattle connection") remains administratively intact. Dependent claims 2–15 — the angled guide channels (claim 2), rigid detent pin (claim 3), axially displaceable detent pin (claims 4–5), rotatable flattened detent pin (claims 6–7), the split detent-pin-segment design (claim 8), and the three alternative lever-to-locking-body couplings (link/claim 11, eccentric/claim 9, toothed/claim 10) — likewise carry no PTAB adjudication.

Estoppel landscape. There is no § 315(e)(2) estoppel against anyone, because § 315(e)(2) is triggered only by a petitioner's institution and termination of an IPR/PGR. No petitioner exists, so no petitioner and no privy is barred. Practically, though, this is an academic concern: for a defendant being asserted against today, the prior-art grounds "still available" are limited not by estoppel but by the patent's expiry. The live validity challenges on this patent were always district-court/RJMOL § 102/§ 103 defenses against the very references the Examiner and the applicant already traversed — DE 21 61 735, US 3,677,195, DE 25 56 000, DE 27 32 460, DE 36 31 097, DE 34 47 178, DE 38 04 354, US 4,185,799, US 4,256,424, and EP-A-0105675 / US 4,496,271 — all of which appear in the "Patent Citations (21)" table and all of which are now available to a defendant without any IPR-estoppel overlay. The most interesting untested vulnerability on this record is the § 103 combination of US 4,256,424 ("Rattle-proof anchor fitting for securing loads to a retainer track" — the closest "antirattle" art) with EP-A-0105675 / US 4,496,271 (the T-shaped-channel main-body/locking-body arrangement the specification itself concedes as known), since the patent's stated point of novelty is precisely the angled guide that makes the clamping distance shrink on locking.

Pattern signals. No repeat petitioner, no defensive aggregator (no Unified Patents, RPX, or Allied Security Trust filing), no PTAB appeal, no IPR certificate, no ex parte reexamination activity surfaced. Ownership is "Individual" (inventor Walter Michler; later Michler-attributed family filings DE202007010755U1, DE102007036449A1, and DE202011108804U1 under "Families Citing this family"). There is no marker of an aggressive PTAB-litigation posture by the patent owner — no serial IPRs defended, no motion-to-amend practice, no Federal Circuit briefing harvested from this patent. If your adversary is citing US 5,489,172, that citation is not backed by any institutional validation of the claims, and it is not backed by a live enforceable term.

Recommended next steps

• Do not spend IPR money. Filing an IPR against an expired, unasserted patent buys nothing but a certificate and fees. Because US 5,489,172 expired 2013-02-06 ("Expired – Lifetime" per the structured data), the six-year damages lookback under 35 U.S.C. § 286 from any complaint filed today (i.e., back to 2020-09-30) captures zero months of infringement. Even under an earlier-filed complaint, the last possibly infringing act is before 2013-02-06, so the § 286 window closed no later than 2019-02-06. An infringement theory built on this patent today is time-barred before it reaches validity.
• If you nevertheless receive a demand citing claims 1–15, test the standing/timeliness premise first, not the merits. Ask for: the reissue or continuation-in-part being actually asserted, the accused article, and the dates of the accused conduct. If the answer is "US 5,489,172 itself, accused conduct after 2013-02-06," there is no case, and the demand letter itself becomes Rule 11 / § 285 exposure for the sender.
• If a family member is what's actually being asserted — e.g., a later original-assignee or Michler-family filing such as DE102007036449A1 / DE202007010755U1 / DE202011108804U1, or a US counterpart thereof — the "no PTAB activity" finding above does not transfer. Re-run this analysis on that patent number; the aged-parent blank docket is a signal about this patent only.
• Verification you should run yourself before relying on the empty docket. (1) PTAB E2E / PTAB Center search by patent number at https://ptacts.uspto.gov/ptacts/public-informations/ (party name search "Michler" as well as the numeral, since a petition may be docketed under the application number 08/137,070). (2) USPTO ODP AIA trial endpoint. (3) CourtListener docket search at https://www.courtlistener.com/ for the numeral and for both "5,489,172" and "5489172" against the Federal Circuit, to confirm no sua sponte appeal exists — I found none, but CourtListener's coverage of pre-2015 dockets is the one place a stale appeal could hide, and I could not complete that final confirmation pass.
• Bottom line for a defendant: no PTAB proceeding means no canceled claims to point at, no FWD to quote, and no § 315(e)(2) estoppel map. Your defense is not a PTAB paper — it is the expiration date, the § 286 bar, and (if the merits ever get reached) the heavily-cited prior-art cluster of US 4,256,424 and EP-A-0105675 / US 4,496,271 against the angled-guide limitation of claim 1.

Confidence statement: I am highly confident that no AIA trial proceeding on US 5,489,172 appears in the USPTO ODP data or in indexed web sources. I am not able to rule out a filing so recent that neither source has indexed it, and I flag that residual gap rather than assert completeness.

I'll verify the assignment record before writing anything. Let me query the assignment databases and related sources.

No assignment hits yet. Let me probe the assignment center directly and check for any litigation or assertion activity.

Let me confirm the absence of assignment records and check for any litigation or corporate context around the inventor.

I could not complete all planned verification calls (search-step limit reached), so I am reporting exactly what was verifiable and flagging what was not. Critically: I found no recorded assignment for US 5,489,172 — and I am not going to synthesize a chain to fill that gap.

Assignment & Ownership Analysis — US 5,489,172

Patent: Quick-release fastening device ("quick-change track lock") · App. 08/137,070 · PCT/EP1992/000917 national stage · Priority DE 4113824.4 (1991-04-27) · Granted 1996-02-06 · Anticipated expiration 2013-02-06 · Status: Expired – Lifetime.

Sourcing note / limitation: My verification relied on the Google Patents mirrored legal-events table for US5489172 (which is populated from USPTO assignment data and is where an "AS – Assignment" event would appear) plus the WO/EP family records, because I hit the tool-call ceiling before I could issue a direct assignmentcenter.uspto.gov query. I did not obtain a direct readout from the Assignment Center. Treat the "no records" call below as high-but-not-certified confidence, and confirm directly at:
https://assignmentcenter.uspto.gov/ (search patent number 5489172) — mirrored at https://assignment.uspto.gov/patent/index.html.

Inventors

Unusual-pattern check — no fire-sale precursor:

• There was no corporate employer from which the inventor could "depart," so the classic all-inventors-quit-within-12-months precursor does not apply.
• The opposite pattern is present: Michler kept filing personally on this technology long after the 1991 priority — DE102007036449A1 and DE202007010755U1 ("Fastening system for the quick detachable fastening of interior components in the cabin of an aircraft," both 2007-08-02) and DE202011108804U1 (2011-12-08) are all in the name of Walter Michler as applicant. That is a 20-year, single-inventor, self-funded prosecution and maintenance program, not a portfolio being assembled for resale.
• A parallel German case, DE4115815C1 (filed 1991-05-15, "Quick-action component fastener…"), is also Michler's.

Original assignee

Individual — Walter Michler (per Google Patents: "Original Assignee: Individual"; "Current Assignee: Individual").

• Entity type: Natural person. No corporation, no LLC, no university, no government body ever appears as assignee on the face of the US, EP, or WO record.
• Product embodying the claims: Not determinable from the record. The published documents indicate a designed-for-manufacture device — Michler explicitly benchmarks it against the aviation industry's "light-duty," "medium-duty," and "heavy-duty" seat tracks and markets it under the names "quick-floor-rail-attachment" and "Quickchange" (spec., Summary of the Invention). But no evidence of a shipped commercial product named in the record was found, and no commercial entity is named.
• Primary line of business: Aircraft/vehicle interior-fitting mechanical engineering (per the address and the Dipl.-Ing. (FH) designator).
• Current status: Individual inventor-owner. The US patent was maintained by the inventor personally to full term — the legal-events log shows maintenance-fee payments for the 4th year (1999-07-12), 8th year (2003-08-28, with a late-payment surcharge), and 12th year (2007-07-30), then anticipated expiration 2013-02-06. No abandonment, no bankruptcy filing, no insolvency event appears anywhere in the chain.

Assignment timeline

There are no recorded assignments for US 5,489,172.

The Google Patents legal-events table for this patent contains only:

• STCF — patent granted (1996-01-25 / grant 1996-02-06)
• FEPP / FPAY / REMI / SULP / REFU — fee-payment procedure events (1998–2007)

It contains no AS (Assignment) event, no SEC security agreement, no merger, no change-of-name, and no license recordation. The "Current Assignee" field resolves to Individual — i.e., the original named inventor remains the owner of record on the face of the patent. There are therefore no reel/frame numbers to report; I am not going to invent any.

Correspondents of record that exist on this family are prosecution agents, not assignment recorders, and should not be mistaken for assignment correspondents:

• Günter Grättinger, Wittelsbacherstr. 5, Postfach 16 49, D-8130 Starnberg, Germany — PCT/EP attorney of record on WO92/19496. Appears once in a prosecution capacity only; no recurrence as an assignment correspondent on this patent.
• Novagraaf Technologies, 2 rue Sarah Bernhardt, 92665 Asnières-sur-Seine Cedex, France — representative of record on the EP counterpart (EP0583295), per INPI. Also prosecution/renewal representation, not an assignment.

(Caution on one tempting false positive: an AS assignment event naming KIDDE, INC. / KOEHLER-DAYTON, REEL/FRAME 003954/0138 surfaces in the same search result set. That event belongs to an unrelated patent, US 4,277,043, not to this chain. Do not enter it into this patent's ownership history.)

Timeline diagram

timeline
    title Ownership of US 5489172
    1991 : DE priority filed by Walter Michler
    1992 : PCT application filed by Michler
    1994 : US national stage entered
    1996 : US patent granted to Michler
    2007 : Michler files new German cases
    2013 : Patent expires lifetime

NPE / troll-pattern signals

Positive counter-signals (anti-troll): 20+ years of continuous personal prosecution and ownership by the named inventor (DE filings in 2007, 2007, and 2011 all in Michler's own name); maintenance fees paid to term; no corporate vehicle ever interposed. This is the profile of an independent engineer's personal portfolio, not an assertion vehicle.

Verdict

Insufficient data — more precisely: no post-issuance assignment chain exists, and the patent has expired.

Justification: The USPTO-derived legal-events record for US 5,489,172 contains only grant and fee-payment events and not a single AS assignment entry across 1996–2013, so the record has "only the original assignment" — which the rubric maps to Insufficient data. That absence is itself the finding: the owner of record remained the original named individual inventor, Walter Michler (Am Lochfeld 7, Eching, DE), who is designated as applicant and inventor on WO92/19496 and who personally maintained the patent to its 2013-02-06 expiration. There is no shell entity, no known asserter, no repeat assignment correspondent, no litigation, and no defensive aggregator — so no NPE signal can be grounded in evidence rather than name-guessing.

Verify at: https://assignmentcenter.uspto.gov/ (patent no. 5489172) · https://assignment.uspto.gov/patent/index.html

Recommended follow-up if you need a certified negative: run the Assignment Center query directly and pull the PEDS/ODP transaction history for 08/137,070. If the Assignment Center returns a record that the Google-mirrored table missed (this happens with very old pre-1997 reel/frame filings and with unrecorded-if-not-required transfers executed abroad), that would be the one scenario that overturns the above — and I would want the reel/frame in hand before restating the chain.

I'll verify the patent record and its citation set against the authoritative source before analyzing.

1. Target patent — identification (verified)

Because the application was filed on 1992‑04‑27 with a foreign priority of 1991‑04‑27, the applicable law is pre‑AIA 35 U.S.C. § 102(a)–(e). All references below are the documents listed on the face of the patent as Patent Citations (21) in the authoritative record; I did not substitute similar numbers.

2. What claim 1 actually requires (the anticipation yardstick)

Anticipation under § 102 requires a single reference disclosing every element. Claim 1 requires, together:

1. main body (1) having clamping edges (22);
2. at least one detent member (19, 40, 59, 67) fixing the lock longitudinally in the track;
3. a locking body (4) guided in the main body, displaceable longitudinally, with at least one mushroom‑shaped locking member (20) for the undercuts;
4. an actuating lever (10) pivotally attached that displaces the locking body longitudinally; and
5. means for guiding the locking body so that the distance between each locking member and the clamping edges becomes smaller when moved from the as‑placed position to the locked position (the antirattle feature — the angled guide channel of FIG. 1a, angle α).

Element 5 is expressly the point of novelty over the closest prior art (the specification: "Nor does it [EP‑A‑0105675] discuss how to establish a play‑free, rattle‑proof connection"). No reference in the citation list appears to disclose all five elements, and in particular none of the cited documents is described as teaching the converging/canted guide that reduces the clamping gap during locking. Accordingly, my honest conclusion is that the citations function overwhelmingly as § 103 obviousness art, not as § 102 anticipation of claim 1. Below I map each reference to the claims it is most relevant to, and flag where any § 102 anticipation is even arguable.

Caveat: I could verify the bibliographic data of every cited document, but I could not read the full disclosure of each cited reference from the retrieved material. Element-by-element anticipation conclusions below that depend on a reference's internal disclosure are flagged as provisional.

3. Closest / most relevant prior art (primary references)

EP 0105675 A2 — East/West Industries, Inc., "Restraining fittings" — priority 1982‑09‑30, published 1984‑04‑18 (§ 102(b)).
This is the closest structural disclosure and the reference the patent itself distinguishes. It discloses a track fitting whose main body has a T‑shaped cross‑section channel in which the locking body is guided, with mushroom locking members, installable in the final position without displacing the article. It therefore reads on claim 1 elements 1–3 and part of 4. However, per the specification, EP 0105675 "does not indicate the manner in which the locking body is displaced" and does not address the play‑free/antirattle connection — i.e., element 5 (and arguably the lever of element 4) is missing.
Potential anticipation: none of claims 1–15 on the present record — it lacks the antirattle guide of claim 1 (and thus any dependent claim, which incorporates claim 1). Strongest § 103 base for claim 1 (with US 4,256,424 or the lever references).

US 4,496,271 A — East/West Industries, Inc., "Restraining fittings" — filed 1982‑09‑30, granted 1985‑01‑29 (§ 102(b)).
US counterpart of EP 0105675 A2; same T‑channel/guided-locking‑body disclosure and same analysis. Potential anticipation: none of claims 1–15; § 103 base.

US 4,256,424 A — Ancra Corporation, "Rattle‑proof anchor fitting for securing loads to a retainer track" — filed 1979‑08‑20, granted 1981‑03‑17 (§ 102(b)).
Directly on point for the problem claim 1 solves (rattle‑proof fastening to a retainer track). Whether it anticipates depends on its mechanism: if it achieves the rattle‑proof fit by the same canted‑guide/camming‑of‑the‑locking‑member approach, it is the single most dangerous § 102 reference for claim 1; if it uses a separate wedge/spring/eccentric compensating element, it is § 103 art only. This reference must be read in full before any § 102 position is taken. It is also a candidate for claim 14 (cam/spring‑pin clamping) if it shows a spring‑loaded clamping pin against the track.

US 3,677,195 A — Ancra Corp, "Anchor fitting for retaining articles in a retainer track" — filed 1971‑09‑03, granted 1972‑07‑18 (§ 102(b)).
Cited in the patent's own background as showing mushroom locking members rigidly connected to the main body with cylindrical detent pins that are axially displaceable in the main body and raised/lowered by a lever. That is precisely the subject matter of claim 4 (detent pin guided in a hole, axially displaceable) and, to that extent, claim 3 is distinguished (claim 3 requires the detent pin be rigid to the main body — the opposite arrangement). Potential anticipation: claim 4 read alone is arguably disclosed; but claim 4 incorporates claim 1, which the reference does not meet (locking members are rigid to the main body, no displaceable locking body, no converging guide), so it is not a clean § 102 hit.

DE 21 61 735 A1 — The Boeing Co., "Retractable cargo fastener" — filed 1970‑12‑09, published 1972‑07‑06 (§ 102(b)).
Same background family as US 3,677,195 (rigid mushroom members; axially displaceable detent pins driven by a lever). Relevance: claims 3/4 lineage; not anticipatory of claim 1.

DE 25 56 000 A1 — Vereinigte Flugtechnische Werke, "Freight store floor rail stop" — filed 1975‑12‑12, published 1977‑06‑23 (§ 102(b)).
Latch‑operated T‑head pin retainer to prevent detachment of the block when unlocked. Relevance: claims 3/4; general track‑fitting art; not anticipatory of claim 1.

US 4,493,470 A — Vereinigte Flugtechnische Werke GmbH, "Rapid action clamping for cooperation with slot tracks" — filed 1982‑08‑30, granted 1985‑01‑15 (§ 102(b)).
Lever‑driven "rapid action clamping" for slot/track work. Relevance: bears on claim 1 element 4 (lever‑actuated clamping) and possibly on the clamping/antirattle concept; not a full claim‑1 disclosure on the record.

4. Secondary/background references

5. Date/hierarchy note on US 5,337,979 A (an anomaly worth recording)

US 5,337,979 A could not be § 102(a) or § 102(b) art against US 5,489,172: it was not published/granted until 1994‑08‑16, after the target's 1992‑04‑27 filing date. It could only be § 102(e) art (a U.S. patent effective as of its filing date) — but its earliest date of record, 1991‑12‑18, is later than the target's 1991‑04‑27 priority date. On the priority date, therefore, it should not be § 102(e) art at all; it would become § 102(e) art only under a non‑priority (actual filing) analysis. I flag this because the citation list shows it among the examiner‑cited references, which is the kind of discrepancy one should verify in the file wrapper rather than resolve by assumption.

6. Bottom line

• Most relevant prior art (ranked): (1) EP 0105675 A2 / US 4,496,271 A (East/West) — closest structure (T‑channel guided locking body, mushroom members) but silent on the displacement mechanism and on the antirattle connection; (2) US 4,256,424 A (Ancra) — directly addresses the rattle‑proof objective and must be read in full before any § 102 position; (3) US 3,677,195 A, DE 21 61 735 A1, DE 25 56 000 A1 — mushroom members plus axially displaceable lever‑driven detent pins; (4) US 4,493,470 A — lever‑actuated rapid clamping to slot tracks.
• § 102 anticipation of claim 1: on the present record, no single cited reference discloses all five claim‑1 elements, chiefly because none is shown to disclose the converging‑guide antirattle means (element 5). The citations are best characterized as § 103 obviousness art.
• Best § 102 arguments, if any, are against dependent claims read in isolation, and only as element‑level disclosures: claim 3 (detent pin rigid to main body — e.g., US 4,185,799 A, EP 0105675), claim 4 (axially displaceable detent pin — US 3,677,195 A, DE 21 61 735 A1, DE 25 56 000 A1), claim 15 (article‑adjustment/intermediate member — seating‑adjustment art). Because dependent claims incorporate claim 1, none of these is a clean standalone § 102 hit.
• Distinguished‑by‑specification references (DE 34 47 178 A1, DE 38 04 354 A1, US 4,185,799 A) fail claim 1 for the reasons the patent states: no actuating lever, or in‑situ assembly rather than a quick‑change lock.

If you want, I can pull the full text of US 4,256,424 A (the key rattle‑proof reference) and of US 4,496,271 A / EP 0105675 A2 and do a true element‑by‑element § 102 chart against claims 1 and 2.

I'll verify the key prior-art references before building the § 103 analysis.

Obviousness Analysis — U.S. Patent No. 5,489,172 under 35 U.S.C. § 103

Scope note: This is a technical/analyst assessment of hypothetical obviousness, not a legal opinion. Per the earlier section of this file, no litigation or PTAB proceeding involving US 5,489,172 was located, so there is no court's claim construction or validity ruling to anchor against, and no prosecution history was available to me. Everything below is built from the patent's own text (authoritative) plus the prior-art references identified in its Background and Citations sections, verified where possible against primary sources. The patent is expired (anticipated expiration 2013‑02‑06), so this matters only for retrospective (past-damages/collateral) purposes or as a defensive-attack template.

1. What claim 1 actually adds over the admitted prior art

The Background of the '172 patent is unusually self‑limiting. The applicant expressly admits that the entire locking principle — place the lock, mushroom heads pass through cutouts, displace half a pitch, drop a detent pin — is old (attributed to US 3,677,195; DE 21 61 735; DE 25 56 000; DE 27 32 460; DE 36 31 097; DE 38 04 354; DE 34 47 178; US 4,185,799), and that a T‑shaped channel in the main body guiding a longitudinally displaceable locking body is disclosed in EP‑A‑0105675:

"The main body used in the known track fastening device comprises a channel with a T-shaped cross section, the locking body being guided in said channel. This publication, however, does not indicate the manner in which the locking body is displaced in the main body. Nor does it discuss how to establish a play-free, rattle-proof connection…"
— '172, Background (https://patents.google.com/patent/US5489172/en)

Those admissions are binding on the patentee and sharply narrow the § 103 gap. Claim 1 therefore reduces to two additions over EP‑A‑0105675, both of which the specification itself concedes are conventional as functions:

1. An actuating lever pivotally attached to the main body that displaces the locking body longitudinally (claims 9/10/11 recite three alternative, admittedly routine couplings: eccentric, toothed rack, articulated link).
2. "Means for guiding" the locking body so that the locking-member-to-clamping-edge distance decreases when going from the as‑placed to the locked position — i.e., the locking body itself performs the anti-rattle clamping (spec/FIG. 1a: guide channels 8 set at a small angle α to clamping edges 22).

Claim-construction point that cuts both ways: claim 1 recites "means for guiding the locking body…", which invokes 35 U.S.C. § 112(f). The only corresponding structure disclosed is the inclined guide channels 8 of FIGS. 1/1a and equivalents. A narrow construction (inclined guide channels) narrows the § 103 exposure; a broader construction (any structure that changes the vertical relation between locking member and clamping edge as the body slides) broadens it. Because FIG. 1a is described as "heavily exaggerated" and the angle is "not discernible in the further drawings," the patentee has little support for any numerical range or criticality — which forecloses the usual "critical angle" non-obviousness argument.

Level of ordinary skill (POSITA): a mechanical design engineer with ~2–4 years' experience in aircraft interior/cargo restraint hardware, familiar with seat tracks of 1‑inch pitch (the '172 and DE 27 32 460 both specify 25.4 mm/1 in. centers), mushroom-head fittings, shear pins, and wedge/cam clamping.

2. The material prior art

3. Combinations that render the claims obvious

Combination A (primary): EP‑A‑0105675 / US 4,496,271 + US 4,109,891 (the US family member of DE 27 32 460) + US 4,493,470

• EP‑A‑0105675 supplies everything in claim 1 except the two additions: main body with clamping surface, T‑channel guide, and a locking body with mushroom-shaped locking members displaced longitudinally to engage the track undercuts (protrusions 50/52 under lip 36 — literally claim 1's "mushroom-shaped locking member adapted to engage undercut portions").
• US 4,493,470 supplies the actuating lever: handle 8 pivotally journaled (bore 15) and coacting with the clamping element, explicitly to satisfy "easy clamping without utilization of tools."
• US 4,109,891 supplies the anti-rattle clamping function performed by forcing the track-engaging members upward against the retaining lips — i.e., exactly the "distance between locking member and clamping edge becomes smaller" result of claim 1, achieved there by pivoting support plates 30/32 with lugs 34/36/44/46 (the same swivel-plate principle the '172 Background attributes to DE 27 32 460). Implementing the same clamping motion as a slight inclination of the guide channel (claim 2) is the substitution of one known linear-to-clamping mechanism (pivoting plate on a screw) for another (inclined slide/cam) with a predictable result.

Combination B: EP‑A‑0105675 / US 4,496,271 + US 4,256,424 + US 4,493,470

US 4,256,424 supplies an express, dedicated "rattle-proof" clamping function (screw-driven wedge/clamp drawing the fitting's shoulders tight against the track), and US 4,493,470 supplies tool-free lever actuation. Substituting the inclined guide channel of claim 1/2 for Ancra's screw-driven U-clamp — so that the same lever stroke that seats the locking body also takes up the clearance — is a foreseeable, efficiency-motivated improvement (eliminating a second adjustment operation and a separate screw).

Combination C: US 4,493,470 + US 4,109,891 + EP‑A‑0105675

Read claim 1 as a system claim: US 4,493,470 gives the lever-actuated mushroom-post/detent-pin track lock; US 4,109,891 gives anti-rattle clamping of the track lips by the very members that engage under them; EP‑A‑0105675 gives the longitudinally slidable (rather than axially movable) locking body. The '172's asserted advance — no need to pre-displace the main body by half a pitch, plus zero play — is the aggregate of these known functions.

Motivation to combine (KSR v. Teleflex, 550 U.S. 398 (2007))

1. Same field, same problem, same classification. All references are aircraft floor/seat track fittings; the '172, DE 27 32 460, US 4,109,891 and the citing art all sit in B64D 11/0696 — "means for fastening seats to floors, e.g. to floor rails" (see '172 Classification section). Combination of references addressing the identical problem is the paradigm case.
2. The patentee's own admissions supply the motivation. The '172 Background states the object was to "permit a play-free, rattle-proof connection" and to be "installable quickly and without tools." Both objectives were already explicit goals in the art: US 4,109,891 ("prevents any rattling or vibration"), US 4,256,424 ("rattle-proof"), US 4,493,470 ("held and fixed without play" / "without utilization of tools"). A POSITA facing the stated problem would look to exactly these documents.
3. Predictable result. Making a sliding guide slightly inclined so the carried clamping member sweeps toward the clamping edge is elementary wedge/cam mechanics; the only variable is angle α, and the '172 gives no numerical range and no criticality data (FIG. 1a is admittedly exaggerated; the angle is said to be "not discernible" elsewhere). In re Applied Materials / KSR: an unclaimed, unspecified dimensional parameter cannot carry patentability.
4. Design incentive / market pressure. The '172 itself recites the commercial pressures (space lost to the 0.5‑inch installation displacement; "quick-change interior"; tool-free conversion during short ground turns). These are the classic "design incentives and other market forces" that KSR says render variation obvious.
5. Known technique to improve similar devices. Bifurcated/straddling detents over a sliding member (US 4,109,891 shear pins 54 straddling support plates 30/32), detent-ball indexing (US 4,496,271), and lever-locked handles (US 4,493,470's crown ring 9) were all known solutions to the sub-problems of claims 8, 12 and 13.

4. Claim‑by‑claim summary

5. Secondary considerations

No secondary-consideration evidence is before me. There is no litigation record (see the earlier section), no IPR/PGR record, and I could not obtain the prosecution history. Possible patentee-side arguments and their likely weight:

• Long-felt need / failure of others — the "quick-change" (no half-pitch displacement) benefit. But US 4,493,470, US 4,109,891, US 4,256,424 and EP‑A‑0105675 all show the industry actively attacking rattle and tool-free installation, and the '172 itself recites the market drivers; a nexus to the specific inclined-guide feature would be needed and is absent.
• Commercial success — not evidenced in the record I can access; note the '172 itself lists a commercial name ("quick-floor-rail-attachment"/"Quickchange"), but naming is not evidence.
• Unexpected results — none disclosed; the '172 does not report test data, noise measurements, or load data for the angle α. This is a real evidentiary gap for the patentee.

6. Where the obviousness case is weakest (best non-obviousness arguments)

1. No reference teaches the inclined guide channel itself, and the purpose is different. US 4,496,271's sloped sliding surfaces (FIG. 7) are disclosed to reduce friction between the sliding member and upper member — not to clamp. Shifting a friction-reduction slope into an anti-rattle clamping feature is a purpose change that a patentee can attack under In re Ratti / "change in principle of operation." The obviousness case on claim 2 must be carried by US 4,109,891/US 4,256,424 (clamping) plus general wedge knowledge, not by the slope teaching of US 4,496,271 alone.
2. US 4,109,891 arguably teaches away from making the locking members themselves the clamp. Its button 52 is deliberately made of nylon/soft aluminum so that it fails above ~7–8 G in order not to interfere with load distribution. A patentee can argue this expresses a preference for a sacrificial, non-load-bearing anti-rattle element — the opposite of claim 1, where the clamp path runs through the load-bearing mushroom members. The counter (and, I think, the stronger view) is that (a) "teaching away" requires the reference to criticize, discredit or discourage the claimed solution — it does not; it merely tolerates failure of the button; and (b) in the '172 the clamping still acts on the track lips, the same interface that carries the load, so no new load path is created.
3. Claim 6 and claim 9 have thin record support. I found no reference of record in the '172 file that discloses a flattened, rotatably mounted detent pin (claim 6) coupled by gearing (claim 7), nor an eccentric (claim 9). These would need supplemental art (e.g., quarter-turn fastener art for claim 6) for a clean § 103 case. Flagging this honestly rather than assuming.
4. § 112(f) construction narrows "means for guiding" to the disclosed inclined channels and equivalents, which reduces the reach of any obviousness holding.
5. Hindsight caution: the combinations must be shown to have been available and motivated as of 1991‑04‑27; the motivation analysis in § 3 is built on the explicit problem statements in the references themselves, which is the strongest available defense against a hindsight attack.

7. Date and procedural caveats (please verify)

• All references in the '172 Citations list predate the 1991‑04‑27 priority date except US 5,337,979 A (Weber Aircraft). Its listed priority date is 1991‑12‑18 and publication 1994‑08‑16 — both after the '172's priority date. It therefore cannot be § 102(a)/(b) art to the '172 on the face of the record. It could only be relevant on a § 102(e) theory if its U.S. filing predates the '172's effective U.S. filing (the record shows the U.S. application 08/137,070 filed 1992‑04‑27, the national stage of PCT/EP1992/000917). Do not rely on it as § 103 art without confirming its filing date and the § 102(e) posture.
• US 4,109,891 A is not on the face of the '172, but it is the U.S. family member of DE 27 32 460, which is cited in the Background and in the Citations list (matched by identical priority date 1976‑07‑19, common assignee UOP Inc., and identical pivotable-support-plate disclosure). I verified the priority/assignee match across two independent records (Espacenet and Google Patents) but have not pulled the U.S. file wrapper to confirm the family declaration itself.
• DE 27 32 460 appears in the record in two versions (A1 and C3) with different claim scopes; the C3 variant carries the load-distributing/pivotable-plate disclosure.
• No prosecution history or litigation record was available, so I cannot confirm which references the examiner actually relied on, what art was distinguished, or whether any claim was narrowed during prosecution to overcome a § 103 rejection. Obtaining the file wrapper (USPTO PatentCenter for application 08/137,070) is the single highest-value next step.

8. Bottom line

• Claim 1 is likely obvious over EP‑A‑0105675 (US 4,496,271) in view of US 4,493,470 (lever actuation) and US 4,109,891 (the U.S. counterpart of cited DE 27 32 460) or US 4,256,424 (rattle-proof clamping). The patentee's own Background admissions remove most of the claim's substance; what remains is the relocation of a known anti-rattle clamping function into the guide for the locking body, an unclaimed-slope, predictable wedge action. Confidence: moderate‑to‑high.
• Claims 2–5 and 8–15 are likely obvious on the same or closely related combinations; claims 8, 12 and 13 in particular are anticipated in substance by US 4,109,891 (bifurcated detent straddling the lug plates) and US 4,496,271 (detent‑ball indexing; spring‑loaded anti‑unlock plunger/pin). Confidence: moderate‑to‑high.
• Claims 6, 7 and 9 are the weak link for a § 103 attack using only the references of record; supplemental art would be needed. Confidence: low‑to‑moderate.
• The strongest patentee rebuttal is the purpose-change/teaching-away argument built on US 4,109,891's deliberately sacrificial nylon button; it is a real but (in my assessment) surmountable obstacle, since that reference neither criticizes nor discourages clamping through the track-engaging members.

Sources: https://patents.google.com/patent/US5489172/en (authoritative patent text, claims and citations); https://patents.google.com/patent/[US4256424A](/patent/US4256424A) ; https://patents.google.com/patent/[US4493470A](/patent/US4493470A)/en ; https://www.freepatentsonline.com/4496271.html (EP‑A‑0105675 family); https://patents.google.com/patent/DE2732460A1 and https://patents.google.com/patent/DE2732460C3 ; https://uspto.report/patent/grant/[4109891](/patent/4109891) and Espacenet DE2732460/US4109891 priority data.