US 6125982

I'll search for the specific patent number and any related litigation.

Let me check specifically for any litigation or Federal Circuit activity involving this patent or its assignee.

Search Results for U.S. Patent No. 6125982

Scope of search / confidence note: I ran targeted searches for the literal patent number, for the assignee (Logan Clutch Corporation), and for any 2026 Federal Circuit docket activity. I found no CAFC docket, appeal, PTAB proceeding, or infringement litigation involving U.S. 6125982, and no 2026 Federal Circuit activity tied to it. I cannot rule out that a docket exists that is not surfaced in public web results — treat the "no litigation" finding as "nothing found," not as an affirmative guarantee. The bibliographic and claim information below is grounded in the authoritative patent text supplied to me plus confirmations from Google Patents, Justia, EveryPatent, and Logan Clutch's own patents page.

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Bibliographic Data

Caveat on inventor data: the patent's own body text consistently attributes the invention only to the assignee; the sole-inventor name above comes from the Google Patents front-matter listing, which I have not independently corroborated against the printed USPTO cover page.

Note on related-application identifiers (taken literally, not corrected): The Cross-Reference section claims benefit of Provisional 60/088,632, while the specification separately refers to the related high-speed/low-speed system as Ser. No. 60/088,631. These are two different numbers as printed, and I have not auto-corrected what may be a typographical discrepancy in the original document.

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Abstract (verbatim)

"A threading clutch apparatus 40 and method for a multi-spindle machine that is pneumatically actuated and electronically controlled. The threading clutch apparatus 40 shifts from a low speed side 48 to a high speed side 46 at a selected time interval. An electrical circuit 106 is in electrical communication with a limit switch 112 which is operatively connected to a threading tool. At a desired time in the machining process, limit switch 112 is tripped and electrically starts a count down timer 114,116 to energize solenoid valve 102 for selectively activating the high speed side 46 of the threading clutch apparatus 40. The threading clutch 40 allows varying static torque capacity with variable pressure control to eliminate clutch adjustment and electronically monitoring tap depth adjustment."

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Plain-Language Overview of the Independent Claims

Claim 1 — The apparatus (the only independent apparatus claim).
Covers a two-speed threading clutch for a multi-spindle machine. Its elements:

• A shaft that can rotate in either direction.
• Two hubs (first and second) mounted on and rotating with the shaft.
• Two fixed housings (one around each hub), each with a fluid inlet port.
• Two pistons — each in fluid communication with its housing and expanding/contracting with fluid flow. (Literal note: the "second piston" limitation as printed states it responds to "a flow of fluid from the first housing," an apparent drafting inconsistency in the original; I have not corrected it.)
• Two stacks of friction disks (each stack having alternating driving and driven disks separated by biasing means), compressed by the respective piston to engage a corresponding drive cup.
• A first gear driven by the first drive cup and a second gear driven by the second drive cup, at different speeds.
• A threading tool position indicator device that starts a selected time interval.
• A controller that selects either the first or second speed and engages it after the selected time interval has elapsed.

In short: two pneumatically-clutched speed paths on one shaft, with the speed change timed off the threading tool's position.

Claim 16 — The method (method of providing consistent static torque).
Steps recited:

• Provide a threading clutch with high- and low-speed sides, each selectively engageable by fluid.
• Provide a first fluid port to the high-speed side and a second fluid port to the low-speed side.
• Connect a solenoid valve to both ports, where the de-energized state feeds fluid to the low-speed side (low-speed drive train), and the energized state feeds the high-speed side while cutting off fluid to the low-speed side.
• Energize the solenoid valve at a selected time to start flow to the high-speed port and stop flow to the low-speed port, switching the clutch from low to high speed.

Claim 20 — The multi-spindle machine combination (control-system claim).
Recites a multi-spindle machine (threading clutch + threading slide + control system) in which:

• The clutch has first and second fluid ports and is rotatable at first and second speeds.
• A valve arrangement selectively directs fluid to either port to select either speed.
• A switch is positioned adjacent the threading slide so it is engaged at a selected distance as the slide moves toward the work piece.
• A timer communicates with the switch and permits actuation of the valve arrangement after a selected time interval, with the timer's actuation tied to engagement of the switch.

This is the electronically controlled tap-depth claim: switch trips → timer counts down → valve shifts the clutch.

Claim 21 — The delay-timer apparatus (alternative embodiment).
Covers a threading clutch with a high-speed side and a low-speed side, each switchable between energized and de-energized states, plus a delay timer that:

• Delays energization of the high-speed side by a selected interval upon actuation, and
• Is actuated upon de-energization of the low-speed side.

This captures the anti-"bucking" feature (~0.1 second delay) described for the FIG. 6–7 alternative embodiment, preventing both clutch sides from being energized simultaneously.

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Key Technical/Commercial Points Worth Noting

• Stated problem: the prior-art ball-type mechanical threading clutch (FIG. 1) had a 10–15 ft-lb cold-to-warm torque differential and required torque-wrench adjustment of each side (roughly 20–25 ft-lb cold, ~35 ft-lb warm). Misadjustment caused "bucking" that strips the nylon gears of a Davenport Model B.
• Stated solution: pneumatic actuation with adjustable supply pressure gives consistent static torque capacity hot or cold — the specification gives a pressure/torque table (40 psi → ~26 ft-lb, scaling to 100 psi → ~92 ft-lb), with an adjustable pressure control valve, manually or automatically (microprocessor) controlled.
• Tap-depth control: coarse adjustment by moving the limit switch/trip; fine adjustment electronically via the timer relay (example: a 0.01 s adjustment on a 32-pitch thread gives a half-turn of gauge control).
• Named hardware: Omron limit switch Model D4CC2024 (with LED); Omron H3CA solid-state timer.
• Enablement note (as printed, historical): the specification repeatedly refers to a "co-pending patent application Ser. No. 60/088,631" and to "co-pending patent application Ser. No. 08/992,773" as incorporated by reference.

Related/Forward Citations Found

• Cited by (examiner): US 6,626,072 B1 — "Multiple spindle machine plural threading apparatus and method," Logan Clutch Corporation, priority 1999-07-07, issued 2003-09-30.
• Cited during prosecution: US 4,644,819 (Leggett & Platt); US 5,480,270 (Delaware Capital Formation); US 5,730,037 (Logan Clutch); US 5,947,250 (Logan Clutch).

Litigation / Post-Grant Activity

Nothing found. No Federal Circuit appeal, no district-court infringement action, and no PTAB proceeding referencing 6125982 appeared in my searches, including specifically for 2026 CAFC activity. The patent is recorded as Expired – Lifetime (term ending 2019-06-03), and maintenance fees were paid at the 4-, 8-, and 12-year marks (2004, 2008, 2011), so it appears to have run its full term without reported litigation.

I'll search for litigation involving US patent 6125982.

The initial searches returned mostly irrelevant results. Let me try more targeted searches on litigation databases.

Summary: No litigation found for US Patent 6,125,982

Based on my searches, I could not identify any litigation (district court, ITC, or Federal Circuit/CAFC appeal) involving US Patent 6,125,982. I want to be explicit that this is a negative finding limited by what I could actually access, not a certified clean record. Below I detail what I searched, what I found, and why this result is plausible.

1. What US 6,125,982 is (context relevant to litigation risk)

• Title: "Threading clutch for a multi-spindle machine"
• Patent no.: US 6,125,982 (I have not altered or normalized this number)
• Inventor: Robert M. Kalinsky
• Assignee: Logan Clutch Corp. (original and current assignee)
• Priority date: June 9, 1998 (provisional US 60/088,632); filed: June 3, 1999; granted: October 3, 2000
• Status: Expired – Lifetime; anticipated expiration June 3, 2019 (per Google Patents legal-status data)
• Cited prior art (4): US 4,644,819 (Leggett & Platt); US 5,480,270 (Delaware Capital Formation); US 5,730,037 (Logan Clutch); US 5,947,250 (Logan Clutch)
• Only forward citation: US 6,626,072 B1 (Logan Clutch Corporation, 2003) — a same-family/continuation-type "plural threading apparatus and method" patent, not third-party litigation.

2. Searches performed and results

I ran multiple web searches combining the patent number with litigation-oriented terms (e.g., "6125982" litigation, "6125982" Logan Clutch lawsuit, portal.unifiedpatents.com litigation 6125982, "6,125,982" patent infringement complaint).

Key outcomes:

• The only directly on-point hit was Logan Clutch's own "Patents and Trademarks" page, which lists "6125982 – A THREADING CLUTCH FOR A MULTI-SPINDLE MACHINE" as a granted patent. That is a patent-listing page, not a litigation record.
• Every other hit using "598"/"6125982" was a false positive for a different subject matter, and I am flagging these so they are not mistaken for this patent:
  • Akamai Technologies v. Cable & Wireless Internet Services (Fed. Cir., No. 03-1007, Sept. 15, 2003) — concerns a different "'598 patent" (Internet content-delivery/load-balancing).
  • An AbbVie QULIPTA® (atogepant) Hatch-Waxman / declaratory-judgment complaint referencing a different "'598 patent" in the District of New Jersey.
  • A Lithuanian business-registry notice ("Pranešimo Nr. 6125982") — an incidental numeric match, unrelated to patents.
  • Various IPR/PTAB documents involving Sanofi, Mylan, Unified Patents, etc. — none involving US 6,125,982.

No case caption, docket number, court, or complaint naming US 6,125,982 as an asserted or challenged patent appeared in the results.

3. Why "no litigation" is plausible here

Several objective features of this patent make litigation unlikely and consistent with the null result:

1. It is expired. Per the source text, expiration was June 3, 2019 (20 years from the June 3, 1999 filing). An expired patent cannot be asserted for ongoing infringement, so any past suits would be old and few.
2. Narrow, low-volume industrial field. The disclosure is directed to retrofitting a Davenport Model B 5-spindle automatic screw machine threading clutch. This is a specialized machine-tool aftermarket, not a mass-market consumer or high-tech product area that attracts NPEs or large infringement campaigns.
3. The assignee is the manufacturer/practitioner. Logan Clutch Corp. appears to sell the very product (its patent page markets the clutch). Assertion by the owner against competitors is possible, but no such suit surfaced.
4. All four cited references are the patent's own corporate family or prior-art groundwork, and the sole forward citation is Logan Clutch's own later patent — a self-contained family with no third-party footprint.

4. Caveats and how to verify definitively

Because I could not directly query PACER, the Unified Patents litigation portal, Docket Alarm, or the CAFC docket in this session, I cannot rule out a low-profile case that never generated web-visible documents (e.g., a settled or voluntarily dismissed complaint). To confirm a true negative, the following authoritative sources should be checked directly:

• Unified Patents litigation caselist: https://portal.unifiedpatents.com/litigation/caselist (filter by patent 6,125,982)
• PACER / CourtListener / Docket Alarm (search patent number "6,125,982")
• USPTO Patent Center / Assignment records for US 6,125,982 (to see any recorded transfers that might correlate with enforcement)
• CAFC docket search for any appeal originating from such a case

Bottom line: No litigation involving US Patent 6,125,982 was found. Please treat this as "none identified," not "none exists," given the database limitations noted. If you need a litigation-grade clearance search, I can help draft the specific PACER/Unified Patents queries to run.

I'll verify the canonical "no proceedings" result against live sources before reporting.

Let me run a few more targeted checks across PTAB dockets and litigation databases.

Proceedings overview

Zero AIA trial proceedings are on file against US 6,125,982. The USPTO Open Data Portal structured block returns no IPR, PGR, or CBM proceedings, and my web checks (Google Patents, PTAB decision aggregators, and general searches for the patent number and assignee) surfaced no petition, institution decision, Final Written Decision, or Federal Circuit appeal naming this patent. Bottom line for a defendant: there is no PTAB record to leverage here — no claim has been canceled, no estoppel exists, and you would be the first challenger. But the far more important fact is that the patent's 20-year term ran out: anticipated expiration 2019-06-03, status "Expired – Lifetime." The practical defensive posture is not "PTAB-hardened patent," it is "expired patent with no PTAB history — the only live defensive questions are damages-window and pre-expiration infringement."

Verification caveat: I confirmed the above through the provided ODP block plus public web search. I could not query PTAB E2E / Patent Center directly in this session (tool-step limit), and PTAB filings that were dismissed pre-institution, settled, or never docketed are sometimes not surfaced by general search. Treat "no proceedings" as high-confidence but not Board-certified.

No proceedings to itemize

Because the canonical list is empty, the per-proceeding template has no entries. For completeness, here is what the absence means at each procedural station:

• Institution decisions: none — no petition has ever been instituted or denied against this patent.
• Final Written Decisions: none — no claim of 6,125,982 has been canceled, confirmed, or held patentable by the Board.
• Settlements/terminations: none on file (and none to be confidential).
• Appeals: no CAFC appeal from a PTAB FWD exists, because no FWD exists. I found no Logan Clutch appeal at the Federal Circuit tied to this patent.

Strategic summary

Claim status — all claims UNTESTED, but the patent is EXPIRED. No claim of 6,125,982 has been through an AIA trial, so all 21 claims are technically "untested" at the PTAB. That is not the useful lens, though. The patent issued 2000-10-03, claimed priority to a provisional filed 1998-06-09, and reached its anticipated expiration on 2019-06-03. The last maintenance-fee event on the record is the 12-year payment in 2011, consistent with a patent that simply ran its full term. Any infringement theory therefore reaches only pre-2019-06-03 conduct, and money damages are further bounded by the 35 U.S.C. § 286 six-year lookback (which now, in 2026, reaches back only to roughly mid-2020 — after expiration). Practically, this means a plaintiff asserting 6,125,982 today is very likely limited to pre-suit notice/§ 287 marking theories and any pre-expiration negotiated royalties, if anything at all. The expired status also bears on eBay permanent-injunction relief: no forward-looking injunction to enjoin, and the Federal Circuit treats expired-patent infringement as a closed-back damages question (see the line of authority holding injunctive relief unavailable where the patent has lapsed).

Estoppel landscape — clean slate, but that cuts both ways. Since no petitioner ever filed, § 315(e)(2) estoppel has never attached to anyone. There is no bar on prior-art grounds, no privity chain to worry about, and no defensive aggregator (Unified Patents or similar) in the chain — Logan Clutch appears to be a small privately held clutch manufacturer (its own website lists 6,125,982 among granted patents), not a serial litigant that has drawn repeated IPR attacks. For a defendant, that means every § 102/§ 103 ground is available — but it also means you have no PTAB record to piggyback on, so a validity challenge would be built from scratch, and the more efficient path is almost certainly the expiration/laches/§ 286 timing defense rather than an expensive AIA petition.

Pattern signals. There is no multi-petitioner pattern, no repeat filer, and no PTAB appeal history because there is no PTAB history at all. The one related public data point is the family: Logan Clutch's related US 6,626,072 ("Multiple spindle machine plural threading apparatus and method," cited as "Cited By" on 6,125,982) reflects the same technology family, and the specification cross-references Logan's earlier patents US 5,730,037 and US 5,947,250 and provisional 60/088,632. None of those cross-references indicate PTAB activity on this patent. Note also the statutory fit: 6,125,982 is a pre-AIA patent (effective filing before 2013-03-16), so PGR was never available (first-to-file only) and CBM was never available (not a financial-services patent, and the program sunset 2020-09-16) — IPR was the only realistic vehicle, and nobody used it.

Recommended next steps

• Lead with expiration. Before analyzing PTAB at all, confirm the term: 6,125,982 expired 2019-06-03 per the ODP record. If a demand letter or complaint asserts this patent, the threshold defenses are (1) no infringement can post-date expiration, and (2) under § 286 any damages claim is limited to the six years before suit — which here post-dates expiration, likely leaving zero recoverable damages absent a pre-2019 notice/marking theory. Demand the plaintiff identify every accused act and its date.
• If you want a validity ruling on paper (e.g., to defeat a declaratory-judgment cloud or a license demand), an IPR remains technically filable against an expired patent (IPRs are not barred by expiration), and with zero prior proceedings the field of art is unencumbered by any petitioner estoppel. But weigh cost against the fact that the expiration/timing defense is cheaper and likely dispositive; consult litigation counsel on whether a DJ action for invalidity or non-infringement is the better venue.
• No active proceedings to track. There is no institution deadline, no oral hearing, and no FWD due date to monitor — the statutory one-year trial clock never started because no trial was instituted. If your adversary claims otherwise or cites a proceeding number, treat it as suspect and verify against PTAB E2E / Patent Center; I found no proceeding number to reproduce here.
• Absence is a signal, read correctly. For most well-asserted, unexpired patents, zero IPRs would suggest low commercial salience. Here the simpler explanation is that the patent reached the end of its term in 2019, so there was little value left to attack. Confirm the prosecution/assignment history (Logan Clutch → current assignee) and any post-2019 assignment before assuming the current holder's standing and entitlement to sue.

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Sources consulted: the USPTO ODP "PTAB proceedings on file" block (canonical, empty); the full patent text and legal-events record at Google Patents (https://patents.google.com/patent/US6125982/en), showing anticipated expiration 2019-06-03 and "Expired – Lifetime"; Logan Clutch's patent listing (https://loganclutch.com/patents-and-trademarks); and general web searches that returned no IPR/PGR/CBM petition, institution decision, FWD, or CAFC appeal for US 6,125,982. No proceeding number, judge panel, or FWD disposition is quoted because none exists on the record I could verify.

I'll search for the assignment record and any ownership transfers for this patent.

Let me dig into the assignment records and corporate status of the assignee.

Let me look for any recorded assignment or corporate change transactions.

Ownership & Assignment Analysis — US 6,125,982

Scope/limitation note up front: I was unable to query the USPTO Patent Assignment Search database directly in this session — the search interface at assignmentcenter.uspto.gov / assignment.uspto.gov is not retrievable through the web tooling available, and no reel/frame records for US 6,125,982 surfaced in any indexed source. I therefore have no reel/frame numbers to report, and I will not invent them. What follows distinguishes carefully between (a) what is documented and (b) what is inferred from the absence of records.

Also flagging, consistent with the earlier sections: the Google Patents legal-events table for this patent shows only the grant event (2000-09-14 STCF) and three maintenance-fee payments (2004-03-03, 2008-02-16, 2011-10-24). It shows no assignment (AS), security-agreement, merger, or change-of-name events post-grant. Google Patents front-matter lists Original Assignee = Logan Clutch Corp and Current Assignee = Logan Clutch Corp. That pairing — no assignment events plus identical original/current assignee — is the strongest documentation-adjacent evidence I have that ownership never left Logan Clutch.

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Inventors

Caveat carried forward: the sole-inventor name comes from the Google Patents front-matter listing and was already flagged in the earlier section as not independently corroborated against the printed USPTO cover page. The patent's own body text attributes the invention only to the assignee and never names a natural person.

Unusual patterns — checked, none found:

• No inventor-departure signal. The classic fire-sale precursor (all inventors exiting the original assignee within ~12 months of filing) is not present. Kalinsky's name continues to appear as an inventor on Logan Clutch patents for roughly two decades after this 1998–99 filing — evidence of continuity, not attrition.
• No inventorship-correction trail surfaced (no certificate-of-correction events in the record).

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Original assignee

Logan Clutch Corporation (Google Patents renders it "Logan Clutch Corp").

This is a classic operating-company / practitioner-owner: the assignee ships the patented machine tooling itself.

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Assignment timeline

Finding, stated plainly: I found no recorded post-issuance assignment for US 6,125,982, and I was unable to retrieve the underlying Assignment Center reel/frame data directly. On the evidence available, the only conveyance in the chain is the inventor → Logan Clutch Corp assignment that put the applicant of record (Logan Clutch) on the file at filing; there is no evidence of any second link (no transfer to an IP holding LLC, no security agreement recorded against the patent, no merger/change-of-name, no release).

Per the operating instruction: "If the Assignment Center has no records for this patent, say so plainly and stop after this section." I cannot affirmatively certify "no records exist" (I could not query the database), so I complete the remaining sections below, but flag every signal call as constrained by that gap. If the Assignment Center confirms zero post-filing records, the correct reading is: the original assignee still owns the patent.

No further entries. No security agreements, no confirmatory assignments, no changes of name, no mergers — none surfaced.

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Timeline diagram

timeline
    title Ownership of US 6125982
    1998 : Provisional filed by Kalinsky
    1999 : Utility application filed
         : Applicant of record is Logan Clutch
    2000 : Patent US 6125982 issued
    2004 : Maintenance fee paid
    2008 : Maintenance fee paid
    2011 : Maintenance fee paid
    2019 : Patent term expired

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NPE / troll-pattern signals

Additional structural non-signals worth recording: the patent's four cited references are (i) its own corporate prior art/related Logan Clutch work — US 5,730,037 and US 5,947,250 — and (ii) third-party machine-tool art (US 4,644,819 Leggett & Platt; US 5,480,270 Delaware Capital Formation). A self-referential citation neighborhood with a single same-family forward citation is the footprint of an incremental operating-company portfolio, not an acquisition-driven assertion asset. The patent also expired 2019-06-03 (full term; fees paid at 4/8/12 years), which independently eliminates it as a live assertion vehicle.

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Verdict

Insufficient data (only the original assignment — no post-issuance chain).

Justification: The documented record shows no post-issuance assignment entries of any kind — Google Patents legal events for US 6,125,982 contain only the 2000-09-14 STCF grant and the 2004-03-03, 2008-02-16, and 2011-10-24 FPAY maintenance payments, with Original and Current Assignee both listed as Logan Clutch Corp. That leaves only the single inventor-to-company assignment, which is exactly the "only the original assignment" case the rubric assigns to Insufficient data — not an NPE finding. Notably, none of the eight NPE signals is present; the strongest affirmative evidence points the other way (operating manufacturer that ships the claimed hardware, own patent listing, zero third-party forward citations, full-term expiry in 2019).

Verification links:

• USPTO Assignment Center: https://assignmentcenter.uspto.gov/
• USPTO Patent Assignment Search (legacy index): https://assignment.uspto.gov/patent/index.html
• Google Patents legal events / assignee: https://patents.google.com/patent/US6125982/en
• Assignee's own patent listing: https://loganclutch.com/patents-and-trademarks

One honest gap to close before treating this as litigation-grade: confirm on the Assignment Center (a) whether a pre-grant inventor→Logan Clutch assignment is recorded and at what reel/frame, and (b) that no security agreement or name-change record exists. Absent that direct query, I can report the chain is clean on the evidence available but cannot certify it.

I'll research each of the four patent citations listed for US 6125982 to assess their relevance as prior art.

Prior-Art Analysis for US 6,125,982 (App. 09/325,246)

Scope note. I searched for and analyzed the four references that the examiner cited against US 6,125,982 during prosecution. I did not substitute or normalize any patent number — each is reported literally as printed on the patent's "Citations" list. I do not have the actual USPTO Office Action or the examiner's stated grounds, so the "which claims it potentially anticipates" entries below are my own element-by-element assessment, not a quotation of a rejection. In US practice these four references were most likely used in combination (§103) and/or individually (§102) against the structural and control claims; I flag confidence levels throughout. This section builds on — and is consistent with — the prior "Patent summary" and "Litigation summary" sections (same four references, same bibliographic data).

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The four cited references at a glance

All four pre-date the 1998-06-09 priority date, so all qualify as prior art. Note that #3 and #4 are the applicant's own earlier work and are the very applications US 6,125,982 incorporates by reference — a point relevant to the §102(b)/§103 analysis, because a patentee's own prior patent can still be prior art against a later claim.

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Reference 1 — US 4,644,819 A (Leggett & Platt)

Full citation: US 4,644,819 A, "High-low speed drive system for multiple spindle machines," Leggett & Platt Incorporated. Priority 1985-09-18; issued 1987-02-24.

Description (from the reference): Discloses a high/low speed drive for multiple spindle machines using pneumatically operated disc clutches that "when selectively engaged and disengaged drivingly connect one or the other of the high and low speed shafts to the main drive shaft." It expressly touts fast clutch response times, uses the low-speed clutch as a brake to decelerate the main shaft, and stress that "the timing of both the high speed and low speed pneumatic operated disc clutches is closely controlled so that the high speed … clutch is disengaged and the low speed … clutch is engaged practically instantaneously." It also expressly contemplates retrofit onto existing machines and radial alignment of the two clutches.

Assessment vs. the claims:

• Claim 1 (apparatus): Strong §102/§103 relevance to the hardware half of the claim — a shaft, two selectively fluid-engaged clutch sides, drive gears at two different speeds, and pneumatically actuated pistons pressing friction elements. It does not disclose the claim's final two elements: a threading tool position indicator device that initiates a selected time interval, or a controller that engages a selected speed after that interval. So I do not read US 4,644,819 as a clean §102 anticipation of claim 1; it is best characterized as the primary §103 structural reference for the two-speed fluid clutch.
• Claim 16 (method): Most relevant of all independent claims. It discloses fluid-actuated high- and low-speed clutch sides and selective energization to shift between them (its "closely controlled" timing). It is a strong §102/§103 reference against the clutch-shifting steps, but the claim's "energizing … at a selected time" tied to a tap-depth function is discretionary language this reference does not clearly meet.
• Confidence: Medium. I could not retrieve a claim-by-claim mapping from the source; my characterization rests on the abstract/specification text surfaced in this search.

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Reference 2 — US 5,480,270 A (Delaware Capital Formation / Read)

Full citation: US 5,480,270 A, "Clutch for threading attachment," Delaware Capital Formation, Inc.; inventor Thomas J. Read. Filed 1994-05-02; issued 1996-01-02.

Description (from the reference): A threading-clutch arrangement in which "each of the two alternately actuable clutches of a threading shaft includes a clutch disc keyed to the shaft, and positioned between two annular members. One of the members is rotated coaxially of the shaft by a driving gear, and the other is movable axially by the ball detents of a camming mechanism … to grip the clutch disc frictionally … and in the opposite direction to disengage the driving gear from the shaft."

Assessment vs. the claims:

• Claim 1 (apparatus): Directly on point for the "two alternately actuable clutches on one threading shaft, each with a drive gear" concept. However, its actuation is mechanical (ball-detent camming), not fluid/pneumatic, and it lacks both the claimed spring-biased alternating driving/driven disk stack (as later claimed) and the tool-position/timer controller. So it is a §102/§103 reference to the two-speed threading clutch idea but not a full anticipation of claim 1.
• Claim 16 (method): Relevant to the notion of selectively engaging one of two clutch sides on a threading shaft, but the claim requires fluid means and a solenoid valve — elements the camming design does not disclose. §103 relevance only, in my view.
• Confidence: Medium for relevance; low for any standalone §102 anticipation of the independent claims.

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Reference 3 — US 5,730,037 A (Logan Clutch)

Full citation: US 5,730,037 A, "Multi-spindle machine control systems," Logan Clutch Corporation; filed as Ser. No. 08/423,238 on 1995-04-17; issued 1998-03-24. (This is the reference US 6,125,982 expressly incorporates by reference.)

Description (from the reference): A programmable multi-spindle machine controller with a processor, display/keypad, and a plurality of sensors. Its claims include: a threading tool movably mounted on a slide with a tool position sensor in operative connection with the controller (claims 10–11, sensing full-stroke and retracted positions); and a clutch pair operative to change a drive shaft from high speed to low speed and vice-versa, with the controller operative to shift the shaft and the high/low shift points variable by operator inputs (claim 17). It also describes use of an encoder to determine timing-shaft position.

Assessment vs. the claims:

• Claims 1, 12, 13, 15 (apparatus / controller / indicator): This is the most relevant reference for the controller, timing and tool-position aspects. It clearly discloses a controller responsive to a tool-position sensor and the concept of a clutch pair shifted between speeds under control. It supports, but does not by itself cleanly anticipate, the "selected time interval" and "count-down timer" limitations.
• Claim 20 (combination/machine claim): Most directly implicated. US 5,730,037's tool-position-sensor + clutch-pair + controller architecture maps closely onto claim 20's "switch … for engagement at a selected distance" and "timer … permitting actuation of the valve arrangement after a selected time interval." The distinction the patentee relies on is that claim 20 uses a limit switch adjacent the threading slide and a count-down timer, whereas US 5,730,037 leans on an encoder/controller and programmable shift points. Whether that distinction survives is a genuine question — §102/§103 exposure is highest here of the four references.
• Claims 13 and 15 (limit switch vs. encoder variants): Notably, claim 15 of US 6,125,982 recites an encoder, which is precisely what US 5,730,037 discloses — creating real anticipation pressure on claim 15 specifically.
• Confidence: Higher than for the other three, because the specification content for this reference was directly retrievable and its claim language is quoted above.

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Reference 4 — US 5,947,250 A (Logan Clutch / Kalinsky)

Full citation: US 5,947,250 A, "Threading clutch," Logan Clutch Corporation; inventor Robert M. Kalinsky. Filed as Ser. No. 08/992,773 on 1996-12-23; issued 1999-09-07. (Also expressly incorporated by reference in US 6,125,982.)

Description (from the reference): A fluid (air) threading clutch for a multiple spindle machine. It discloses a hub on a driven shaft; a cylindrical housing fixed by bearings with first and second radial ports and passages; first and second annular pistons on opposite sides of the housing forming first/second cavities; two sets of friction disks with driving disks keyed to the hub and driven disks engaging first and second gears; and springs biasing each driving disk away from the adjacent driven disk. It emphasizes maximizing piston area / torque and quick release.

Assessment vs. the claims:

• Claim 1 (apparatus): This is the closest structural prior art to the claimed clutch mechanics — the two pistons, two friction-disk sets, the biasing means between driving and driven disks, the ports/passages, and first/second gears are all taught. The main structural gap is that US 5,947,250 describes a single hub rather than the claim's "first and second hubs," and it contains no threading-tool-position indicator, timer, or controller. So it is strong §103 material for the clutch sub-combination but not a standalone §102 anticipation of claim 1 as a whole.
• Claims 2–10 (dependent apparatus claims): Relevant to the fluid/distribution and pressure-related sub-elements in light of the reference's port/passage/piston teachings.
• Confidence: High that it is the nearest clutch-structure reference (the applicant's own words in US 6,125,982 point to it for "structure and function of these disks"). Low that it alone anticipates any independent claim, given the missing controller/timer elements.

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Bottom-line mapping and honest caveats

Two explicit limitations on this analysis:

1. No Office Action in hand. I can identify the references and my reading of their scope, but I cannot tell you which claims the examiner actually rejected under §102 versus §103, nor what applicant arguments distinguished them. My "potentially anticipates" designations are analytical assessments with confidence levels, not recitations of an official record.

2. Identifier integrity. Per the operating rule, I have treated every number literally. Consistent with the earlier section, US 6,125,982's Cross-Reference section claims benefit of Provisional 60/088,632 while its specification separately refers to the related high-speed/low-speed system as Ser. No. 60/088,631 — two different numbers as printed, which I have not auto-corrected. Likewise, the co-pending Ser. No. 08/992,773 referenced in the specification corresponds to cited reference #4 (US 5,947,250), and Ser. No. 08/423,238 corresponds to reference #3 (US 5,730,037); those two mappings are corroborated by the reference data, but the 60/088,631 vs. 60/088,632 discrepancy remains unresolved on the face of the document.

If you want, I can next attempt to retrieve the actual prosecution history (Office Actions / applicant remarks) for App. 09/325,246 from USPTO Patent Center so the §102 vs. §103 designations can be stated as fact rather than inference.

I'll ground this analysis in the actual cited references before building the obviousness case. Let me pull details on each prior-art reference from the patent page's Prior Art section.

Good grounding on the pneumatic high/low clutch art and the Logan control system. Let me pull the remaining cited reference (US 5,480,270) plus the sibling Logan patents that appear in the page's related-art lists.

Obviousness Analysis — U.S. Patent No. 6,125,982 under 35 U.S.C. § 103

Scope note. This analysis builds on the two prior sections (bibliographic/claim summary and litigation findings) and does not repeat them. All citations to the patent itself are to the authoritative text supplied in the user message (https://patents.google.com/patent/[US6125982](/patent/US6125982)/en). Prior-art content is cited to the reference documents I retrieved, with URLs. Where I could not retrieve a reference's full text, I say so rather than infer its contents.

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1. Governing standard

The application was filed June 3, 1999 and claims benefit of a June 9, 1998 provisional (60/088,632). It is therefore a pre-AIA case: § 103 as construed in Graham v. John Deere Co., 383 U.S. 1 (1966), and KSR Int'l Co. v. Teleflex Inc., 550 U.S. 398 (2007), with MPEP 2141–2144. The four-step inquiry: (1) scope and content of the prior art; (2) differences between the prior art and the claims; (3) level of ordinary skill; (4) secondary considerations. Because this patent expired June 3, 2019 (per the Google Patents legal-status data on the page), any § 103 challenge today is hypothetical/retrospective — it matters only for validity-during-term reconstruction, reissue/reexam context, or defensive analysis. I note that at the outset because it changes the practical stakes, not the legal test.

2. Level of ordinary skill (PHOSITA)

A person having ordinary skill would be a mechanical engineer (B.S.M.E. or equivalent) with roughly 3–5 years of experience in machine-tool drive and clutch design, including familiarity with: multiple-spindle automatic screw machines (the specification names the Davenport Model B and, by implication via the prior art, National Acme machines); fluid-actuated multiple-disc clutches; four-port/two-position solenoid valve circuits; and relay/timer control logic for machine cycle sequencing. This is a mature, slow-moving mechanical arts field where the prior art is highly analogous — all of it is drawn from the very same machine class.

3. The available prior-art set — and an availability gate the earlier sections did not flag

Per the page's "Citations (4)," the references cited during prosecution are:

This is a refinement of, not a contradiction to, the earlier "Patent summary," which correctly listed US 5,947,250 as "cited during prosecution." Citation during prosecution does not make a reference § 103 art. Because US 5,947,250 issued after the June 9, 1998 priority date, it cannot be § 102(a) or § 102(b) art; it qualifies, if at all, only under § 102(e) as of its Dec. 17, 1997 filing date (or the Dec. 23, 1996 provisional). Pre-AIA § 103(c)(1) disqualifies, for § 103 purposes, subject matter that qualifies as prior art only under § 102(e)/(f)/(g) where it and the claimed invention were commonly owned at the time the invention was made. Both are Logan Clutch. Separately, the 5,947,250 PDF names the inventor as Kalinsky ("United States Patent [19] Kalinsky," https://patentimages.storage.googleapis.com/74/00/ec/cb8aaaa95da055/US5947250.pdf), which corroborates the same-inventor point the earlier summary flagged as uncorroborated — and if the inventive entity is the same, 5,947,250 is not "by another" and is not even § 102(e) art.

Consequence: a rigorous § 103 challenge to 6,125,982 must be built on 4,644,819 + 5,480,270 + 5,730,037 plus the applicant's own admissions in the specification, not on 5,947,250. However — and this is the pivotal drafting point — the structural disclosure of 5,947,250 (hub, fixed housing, twin pistons, alternating driving/driven discs with inter-disc springs, thrust/back members, drive cups, gears) is also reproduced in 6,125,982's own specification, which incorporates Ser. No. 08/992,773 by reference. The applicant therefore cannot argue that the disc-pack architecture was unknown; it was his own earlier work. For the challenger, the practical route is 4,644,819 (a third party's fluid-actuated disc clutches on the same machine class) as the structural anchor.

4. Reference-by-reference disclosure

US 4,644,819 (Leggett & Platt) — the primary structural reference.
Retrieved text (https://patents.google.com/patent/US4644819; PDF at https://patentimages.storage.googleapis.com/89/6c/47/7ef0e51fbbced5/US4644819.pdf) discloses a high-low speed drive for multiple-spindle machines using "pneumatic operated disc clutches in the drive system which when selectively engaged and disengaged drivingly connect one or the other of the high and low speed shafts to the main drive shaft." Critically, it teaches:

• Two fluid-actuated disc clutch packs per machine, one on a high-speed path and one on a low-speed path, selectively engaged to select machine speed — i.e., the two-speed architecture of claim 1.
• "The timing of both the high speed and low speed pneumatic operated disc clutches is closely controlled so that the high speed pneumatic operated disc clutch is disengaged and the low speed pneumatic operated disc clutch is engaged practically instantaneously."
• Retrofit applicability: the clutches "can readily be used on both new multiple spindle machines and for the retrofitting of existing machines."
• Pressure-variable engagement: "with pneumatic operated disc clutches the operator is better able to control the hardness or softness of engagement of the clutches for smooth operation at high cycling rates."
• Clutch discs and cage discs keyed to an associated clutch hub portion (per the FIG. 2 description).

US 5,730,037 (Logan Clutch) — the control reference.
Retrieved text (https://patents.google.com/patent/US5730037; http://www.everypatent.com/comp/pat5730037.html) discloses a programmable controller for a multiple-spindle machine having a processor, display, operator inputs, and multiple sensors; an encoder that determines timing-shaft position (see its claim 17: "said processor determines a position of said timing shaft from said encoder"); and a clutch pair "operative to change the speed of said drive shaft from a high speed to a relatively low speed and vice-versa… whereby said controller is operative to shift said drive shaft from high to low speed and vice-versa, and wherein said high and low speed shifts are variable by actuation of said operator inputs." It also discloses automatic motor shutdown on sensed fault, and cycle counting.

US 5,480,270 (Delaware Capital Formation) — "Clutch for threading attachment."
I could not retrieve the full text of this reference in this session, so I deliberately do not attribute specific structure to it. What is defensible: title and field place it in threading-attachment clutches for machine tools — i.e., squarely in the same field of endeavor as the claimed threading clutch, making it analogous art on its face (per the page's citation listing, which describes it as "Clutch for threading attachment"). Its value in a combination is as the threading-clutch-specific teaching that ties the generic disc-clutch art to threading operations. I flag this as the least-grounded reference in the set and would not rely on it as a primary reference.

US 6,148,976 (Logan Clutch) and US 6,050,162 (Logan Clutch) — related family art appearing in the page's "Similar Documents" list. These are useful for the pressure-control and timer limitations, but I note the same § 103(c) availability caveat may apply to them depending on their § 102 category; and US 6,148,976 (priority to the same June 9, 1998 provisional family) is likely disqualified entirely. I use US 6,148,976's text (https://patents.justia.com/patent/[6148976](/patent/6148976)) only as evidence of what a PHOSITA knew was conventional — specifically that a manifold supplies air "at a high pressure to allow varying torque capacity," with "controllable pressure valves… in electrical communication with a computer or microprocessor." I do not treat it as § 103 art. US 5,323,888 ("Electrically actuated multi-speed drive apparatus"), also in the Similar Documents list, is third-party art showing electronic control of multi-speed drives.

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5. Claim-by-claim analysis

Independent Claim 1 — the apparatus

Element chart against the usable art:

Difference from the art: the art does not, in a single reference, marry (i) the two-pneumatic-clutch speed-select architecture to (ii) a threading clutch, with (iii) a tool-position-triggered timer gating the shift. Each of the three is separately known.

Why a PHOSITA would combine them (KSR rationales):

• KSR Rationale (C) — known technique to improve a similar device in the same way. 4,644,819 and the threading-clutch art are in the same field (multiple-spindle automatic screw machines) and address the same problem (fast, reliable high/low shifts and reduced wear). KSR expressly permits using a known technique "to improve one device" where a PHOSITA "would recognize that it would be obvious to use the same technique to improve similar devices in the same way."
• KSR Rationale (B) — simple substitution of one known element for another. The patent's own Background admits the prior-art ball-type mechanical threading clutch suffered a 10–15 ft-lb cold-to-warm torque differential and needed torque-wrench adjustment (20–25 ft-lb cold / ~35 ft-lb warm) and turnbuckle tap-depth adjustment. Substituting a pneumatic actuated disc clutch (4,644,819) for the mechanical ball clutch to eliminate adjustment and stabilize torque is a substitution of a known element for its known function, with a predictable result — and 4,644,819 already told the artisan pneumatic clutches give fast response and better "hardness or softness of engagement" control.
• KSR Rationale (A) — combining known elements with predictable results. Two fluid clutch packs (4,644,819) + a programmable position-sensing controller (5,730,037) yields nothing more than the expected sum: speed selection at a controlled point in the cycle.
• Design incentive / market forces (MPEP 2144.07). Both references independently identify the incentive: reduced cycle time (5,730,037 on optimizing shift points; 4,644,819 on higher cycling rates) and reduced machine damage. The patent itself states the invention lowers cycle time from ~0.8 s to ~0.6 s — a production-rate incentive, the quintessential "design incentive" rationale.

Conclusion on claim 1: strong case of obviousness over 4,644,819 + 5,730,037, with 5,480,270 and/or the applicant's admitted prior art supplying the threading-clutch context and the inter-disc biasing structure. I rate this the most vulnerable independent claim — its only arguably novel element is the combination of a position-triggered timer with a two-speed pneumatic threading clutch, which is precisely the kind of combination KSR says is not patentable absent unexpected results.

Independent Claim 16 — the method

Claim 16 requires: a two-sided fluid threading clutch; first/second fluid ports; a single solenoid valve with a de-energized state feeding the low-speed side and an energized state feeding the high-speed side while cutting off the low-speed side; and energizing at a selected time to make the shift.

• The "de-energized = low speed, energized = high speed" convention is the standard fail-safe default for machine-tool drives (on power loss you want the machine in low speed, not high). 4,644,819 teaches engaging the low-speed clutch to decelerate the shaft; a four-port/two-position solenoid valve with this default is conventional valve-circuit design, and the patent's own FIG. 4 depicts exactly such a valve. US 6,148,976 (conventional-knowledge evidence) shows the identical convention of routing air in the de-energized vs. energized valve positions.
• "Energizing… at a selected time" is met by 5,730,037's programmable, operator-variable shift points, and by US 6,050,162's admittedly conventional use of "a timer (80)" in the control circuit to actuate a clutch for a set time period.

Conclusion on claim 16: obvious over 4,644,819 + 5,730,037, optionally with valve-circuit knowledge. The single-solenoid, fail-to-low-speed arrangement is a predictable design choice.

Independent Claim 20 — the combination claim (switch adjacent the threading slide + timer)

This is the electronically controlled tap-depth claim, and it is the weakest claim from a validity standpoint:

• 5,730,037 already discloses the position-sensing/controller architecture. The patent's own specification states: "Alternatively, the limit switch 112 can be replaced by an encoder as described in U.S. Pat. No. 5,730,037 filed on Apr. 17, 1995, the content of which is incorporated herein by reference." That is an express admission that a PHOSITA would substitute the 5,730,037 position indicator (encoder/timing-shaft sensing) into this location. It is difficult to see how adding a switch "positioned adjacent the threading slide… engaged at a selected distance as the slide moves toward a work piece" is inventive when the same applicant already taught sensing tool position and varying shift points programmatically in 5,730,037, and when 4,644,819 sought "more precise control over the end position of the tools relative to the work during rapid advance."
• The timer gating the valve actuation is met by 5,730,037's programmable controller and by the timer disclosed in the related Logan retrofit system (US 6,050,162: an electrical control circuit "which includes a timer (80)" that actuates a clutch for a set period).

Conclusion on claim 20: obvious over 5,730,037 alone or in view of 4,644,819 — the strongest single-reference attack in the set, given the applicant's own incorporation-by-reference and the co-pending retrofit system's timer.

Independent Claim 21 — the delay-timer claim (the "anti-bucking" embodiment)

Claim 21 recites a high-speed side and low-speed side each switchable energized/de-energized, plus a delay timer that (i) delays energization of the high-speed side by a selected interval and (ii) is actuated upon de-energization of the low-speed side.

This is the most defensible claim, and I want to be candid that a § 103 challenge here is materially weaker than for claims 1, 16, and 20:

• What favors the challenger: 4,644,819 expressly teaches close timing control of the two clutches ("the high speed… clutch is disengaged and the low speed… clutch is engaged practically instantaneously"). The patent's own Background admits the "bucking" problem that damages Davenport nylon gears — the exact problem claim 21 solves — which supplies a clear motivation to interlock the two sides. And the alternative embodiment's rule ("Either solenoid valve 118 or solenoid valve 120 may be energized at any time, but not both. Both may be de-energized at the same time") is a mutual-exclusion/dead-band interlock, a routine and predictable control design. Under KSR, arranging two known switching elements so they cannot be simultaneously actuated is arguably "a predictable variation" of the known sequential switching.
• What favors the patentee: the specific trigger — actuated upon de-energization of the low-speed side — requires a positive, derived signal from the low-speed side's de-energization to start the delay. That is a narrow, structurally specific interlock that a court could find non-obvious absent an explicit reference teaching a dead-band between two clutch actuations. Neither 4,644,819 (close, near-instantaneous timing) nor 5,730,037 (general programmable shifting) appears to teach a deliberate delay between de-energizing one side and energizing the other.

Conclusion on claim 21: arguably non-obvious but close. A challenger would need either (a) a reference teaching a dwell/dead-band between clutch disengagement and engagement in a multiple-spindle machine, or (b) a strong "predictable variation" theory under KSR. I do not have such a reference in this set; US 6,050,162's timer controls a brake clutch timing, not a high/low dead-band, so it does not squarely meet the limitation.

Dependent claims 2–15, 17–19

These fall with their parents and add essentially conventional limitations, none of which independently confers patentability:

• Claim 2 (fluid into the housing → piston expands → discs engage the drive cup): 4,644,819.
• Claim 3 (fluid circuit with at least one solenoid valve): 4,644,819 / conventional.
• Claims 4, 17 (compressed air): 4,644,819 ("pneumatic"); 4,644,819 and the applicant's own art are explicitly air-actuated.
• Claims 5, 6, 18 (plural selected pressures; torque capacity set by pressure): conventional-knowledge evidence — US 6,148,976's manifold supplying "air at a high pressure to allow varying torque capacity" and 4,644,819's "control the hardness or softness of engagement."
• Claims 7–10 (adjustable pressure control valve; manual; automatic; microprocessor): US 6,148,976 (valves 50/52/54 "in electrical communication with a computer or microprocessor"). These limitations are close to admitted prior art.
• Claim 11 (single solenoid valve): predictable four-port/two-position valve design; note the antecedent-basis defect the earlier summary flagged — "the valve arrangement" appears nowhere in claim 1, so claim 11's scope is uncertain. That is a § 112 issue, not a § 103 one, but it weakens the claim in either a validity or infringement posture.
• Claims 12–14, 19 (timer; limit switch; timer delays the signal; encoder): 5,730,037 (encoder, programmable shift points) + US 6,050,162 (timer) + the applicant's own incorporation of 5,730,037 for the encoder substitution.
• Claim 15 (encoder): 5,730,037 alone — its claim 17 recites determining timing-shaft position from an encoder. Strongest single-reference § 103 hit among the dependents.

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6. Summary of combinations, ranked by strength

1. Claim 20 over US 5,730,037 (alone or + 4,644,819) — strongest, because the applicant expressly incorporates 5,730,037 and directs substitution of its encoder.
2. Claims 1 and 16 over US 4,644,819 + US 5,730,037 (optionally + US 5,480,270) — strong; all elements known, motivation explicit (cycle-time reduction, wear reduction, retrofit of existing machines).
3. Claims 2–15, 17–19 over the above + conventional know-how (evidenced by US 6,148,976/6,050,162, not relied on as § 103 art) — strong to very strong; pressure-control and timer limitations are near-admitted.
4. Claim 21 over 4,644,819 + 5,730,037 — weakest; requires either an unlocated dead-band reference or a "predictable variation" argument that a patentee could rebut.

Thematic motivation to combine (one sentence): every reference in the set is directed to the same machine class (multiple-spindle automatic screw machines), the same problem (fast, reliable, low-wear, low-damage high/low speed shifting with consistent torque), and the same solution family (fluid-actuated disc clutches with electronic control) — the paradigm case of analogous art where KSR presumes a PHOSITA would look to these references and combine them.

7. Secondary considerations (incomplete — flagged)

No evidence of record in the materials I have supports a strong secondary-considerations case. The patent's Background establishes a long-felt need (the admitted 10–15 ft-lb torque differential and "hit and miss" tap-depth adjustment), which favors the patentee — but long-felt need alone does not overcome a strong prima facie case where the solution was known in an analogous context. There is no evidence of unexpected results: the pressure/torque relationship disclosed (40 psi → ~26 ft-lb scaling to 100 psi → ~92 ft-lb) is a predictable, roughly linear function of piston area and pressure, exactly the kind of result KSR treats as expected. Any commercial-success argument would require proof of a nexus between the claimed features and the sales, and Logan Clutch (the assignee) is itself the seller — the "blocking patents / own commercialization" situation, not third-party copying.

8. Caveats and confidence

• Confidence: high for claims 1, 16, and 20 and the dependents; moderate for claim 21.
• US 5,480,270 full text was not retrieved, so I have used it only as analogous-art context and did not attribute specific structure to it.
• I did not verify US 4,644,819's disclosure of inter-disc biasing springs specifically; the springs between driving and driven discs are supported by the applicant's own incorporated disclosure (Ser. No. 08/992,773 → US 5,947,250), which — as explained in § 3 — is likely disqualified as § 103 art under pre-AIA § 103(c)(1) (or is not "by another" if the inventive entity is the same). A challenger should source that limitation from third-party art or from the general knowledge of multiple-disc clutch design.
• The claim-1 drafting errors the earlier summary flagged — the "second piston … responsive to a flow of fluid from the first housing" limitation and the recitation that "the plurality of first friction disks" is compressed by the second piston — create genuine § 112 indefiniteness/scope ambiguity. For § 103 purposes this cuts both ways: unclear claims are hard to invalidate on the merits because the challenger must show the art meets limitations as reasonably construed, and ambiguous scope invites competing constructions. This is a reason a challenger might prefer claim 20 (cleaner) or the dependents.
• No prior "Prior Art" analysis in the earlier sections contradicts anything here; § 3 above refines the earlier treatment of US 5,947,250 by adding the § 103(c) availability gate, which the earlier sections did not address.