US 6666773

I'll search for authoritative records on this specific patent number.

Let me run more targeted searches.

Let me check for litigation/CAFC 2026 docket activity and current USPTO status.

Summary — US Patent 6,666,773

Note on identifiers: I interpreted "6666773" literally as US 6,666,773 B1 (application US10/385,903). No other patent number was substituted. The authoritative full text of this patent was supplied in your message; I treated it as controlling over search results, and used searches only to corroborate and to check for litigation.

Bibliographic data

Abstract (as issued): A zip line thrill ride system includes a cable suspended between an upper cable support tower/platform (harnessing, loading, take-off) and a lower cable support tower/platform (landing, unloading, unharnessing). Multiple substantially identical trolleys quickly engage and disengage the cable. The trolley includes a frame of generally I-beam cross section; a generally tubular brake retainer with a longitudinal slit is welded to an upper rear portion of the frame. A grooved, generally cylindrical brake made of a durable polymeric material is rotatably affixed within the tubular brake retainer. When the trolley is affixed to the suspended cable by sliding the cable into the slit and rotating the brake, the grooved insert rides against the suspended cable and generates friction.

Plain-language overview of the independent claims

Claim 1 — Zip line transport system (tower-to-tower + trolley with rotatable "lock-in" brake).
The system combines upper and lower support towers, a suspended cable, and at least one trolley. The trolley has:

• a frame;
• a tubular brake retainer with a central axis and two open ends, mounted at the rear of the frame, with a full-length primary longitudinal slit on its side;
• a cylindrical, abrasion-resistant brake sitting rotatably and concentrically inside the retainer, with a linear longitudinal groove that the cable rides in — the bottom of the groove rubs the underside of the cable. The groove is centered on a plane through the retainer's central axis and can be aligned with the slit, so the cable can be slipped in through the slit and then locked in by rotating the brake arcuately;
• a pulley above the middle of the frame, with a circumferential groove riding on the top of the cable, its rotation axis horizontal and perpendicular to the retainer axis, and mounted far enough from the brake/retainer that an at-least-cable-diameter gap exists (this gap is what lets the trolley be hung on and off the cable);
• a lever arm adjustment bracket on the front of the frame that can be moved fore-and-aft to set how hard the brake groove presses on the cable (i.e., the speed-control/tuning adjustment).

Claim 9 — Zip line transport system (broader trolley-centric version).
Covers essentially the same system but describes the trolley more generically: a frame; a brake assembly at the rear having an abrasion-resistant brake with a longitudinal linear groove whose bottom slides on the cable underside; a pulley mounting bracket attached to and extending above a central portion of the frame with a pulley whose circumferential groove rides on the cable's upper surface; and a fore/aft positionable lever arm adjustment bracket on the front for setting brake pressure. Notably, the final element recites "the rider mounting bracket being positionable fore and aft," although no "rider mounting bracket" was previously introduced — a likely antecedent-basis defect in the issued text (the Certificate of Correction of 2019-05-21 may bear on this; I have not verified the corrected text).

Claim 15 — Zip line transport system (second, slightly different generic framing).
Again the towers, cable, and trolley: frame; rear brake assembly with an abrasion-resistant grooved brake riding the cable underside; a pulley rotatably mounted to a middle portion of the frame with a circumferential groove on the cable's upper surface; and a fore/aft positionable lever arm adjustment bracket on the front portion to adjust brake-to-cable pressure. This claim omits the "pulley mounting bracket extending above" language of claim 9.

Dependent claims (brief)

• 2 / 16: Brake material selected from Teflon®, nylon, high-density polyethylene, and composites.
• 3 / 12 / 18: Brake retainer also has an arcuate slit (non-intersecting the longitudinal slit) spanning 90–120°.
• 4 / 13 / 19: A bolt through the arcuate slit secures the brake and limits rotation to that 90–120° arc.
• 5 / 14 / 20: The arcuate slit intersects a locking longitudinal slit spaced from both ends of the retainer.
• 6: Frame is generally I-beam cross-section, fabricated from metal plate stock.
• 7: Adds the terminal trap and spring assembly: a ramped trap slidably mounted near the lower tower, plus at least one coil-spring assembly with weighted bushings on the cable; the frame's downwardly-slanted bumper nose is forced down by the trap's internal ramp, increasing brake pressure and transferring momentum to the trap, accelerating the bushings and compressing the spring.
• 8: Method-style dependent claim reciting the installation sequence (rotate brake to align groove with slit → position trolley below/oblique to cable → elevate so cable enters the gap → align so cable enters slit/groove and pulley sits over cable → seat pulley → rotate brake to lock).
• 10: Front portion of frame has a longitudinal adjustment slot, a parallel linear array of evenly spaced apertures, and a removable locking pin to secure the bracket.
• 11 / 17: Detailed recitations of the tubular brake retainer, slit geometry, concentric rotatable brake, and the lock-in-by-rotation sequence.

Operational details recited in the specification (context for the claims)

• Referenced installation: a zip line thrill ride at Park City, Utah — cable ≈ 805 m (0.5 mile), vertical drop ≈ 183 m (600 ft); four parallel cables/towers permitting four simultaneous riders.
• Speed control: the trolley's polymeric brake presses on the cable and generates friction. Rider position on the lever-arm adjustment bracket sets brake pressure: closer to the handle/clevis = higher max speed; farther = slower.
• Note an internal discrepancy in the specification's speed figure: the Background and the CIP publication US 2004/0198502 A1 state the ride is limited to "no more than about 55 m.p.h.," while the "Preferred Embodiment" section states "no more than about 70 m.p.h." Both appear in the authoritative text as provided.

Uncertainty / caveats

1. Assignee: Google Patents lists the assignee as "Individual" (original assignee: Individual). A 2011 news report (Fosters.com, "Gunstock rebuffs patent challenge," https://www.fosters.com/story/news/2011/03/26/gunstock-rebuffs-patent-challenge/50150983007/) states that Zip-Flyer LLC held an exclusive license to the patent and that a licensing company purchased it from Richardson — a license is not an assignment, so I cannot confirm a recorded change of ownership. I found no USPTO assignment record in my search results. Treat "current assignee: Individual" as the Google Patents listing, not a verified chain of title.
2. CAFC 2026 dockets: I searched for Federal Circuit 2026 activity tied to this patent and found no results. I cannot confirm any CAFC appeal in 2026. The only litigation reference surfaced is the Utah District Court case 2:10-cv-01031 (2010) and the related 2010–2011 dispute described in the news article (ZipHoldings LLC / Terra-Nova vs. Zip-Flyer and Troy Richardson, including a challenge to inventorship). The patent's term is expired (anticipated 2023-03-10), which makes live 2026 appellate activity unlikely but not impossible (e.g., a lingering damages/licensing dispute) — I simply have no authoritative record of one.
3. Certificate of Correction (2019-05-21): The claim text quoted above is from the Google Patents full text supplied to me. Because a Certificate of Correction issued in 2019, the officially corrected claim wording may differ; I have not verified the corrected text.
4. Claim 9 antecedent basis ("the rider mounting bracket") appears defective on its face in the text provided; I flag this as observed in the source rather than as a legal conclusion.

Sources consulted/cited: Google Patents US6666773B1 (https://patents.google.com/patent/US6666773B1/en); US 2004/0198502 A1 (CIP of this patent, confirming the "issued on Dec. 23, 2003 as U.S. Pat. No. 6,666,773" relationship); Fosters.com 2011 article on the Gunstock/Zip-Flyer dispute; Unified Patents litigation entry for Utah District Court case 2:10-cv-01031.

I'll search for litigation involving US patent 6666773, using the litigation portals and case data.

Let me search the litigation portals directly for this specific patent.

I found a strong lead — a Zip-Flyer, LLC licensing/enforcement campaign. Let me dig into the specific cases.

Summary

Based on my searches, one litigation matter referencing US Patent 6,666,773 is documented (in the Google Patents litigation record for this patent), and there is strong corroborating evidence of a related patent-enforcement dispute. I was not able to retrieve a full PACER docket or CAFC record within search limits, so some elements below are marked as unverified.

I did not auto-correct any identifiers; all numbers are reported as they appear in the sources.

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1. Confirmed litigation entry (from the patent's own record)

Source: The Google Patents page for US6666773B1 states, under the litigation field:

"US case filed in Utah District Court — litigation — Critical — https://portal.unifiedpatents.com/litigation/Utah%20District%20Court/case/2%3A10-cv-01031 — Source: District Court — Jurisdiction: Utah District Court"

Caveat: I could not open the Unified Patents case page or a PACER docket for 2:10-cv-01031 within the available searches. The caption, party names, exact filing date, and disposition are therefore unverified.

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2. Corroborating evidence of the dispute (parties and subject matter)

A Foster's Daily Democrat news article ("Gunstock rebuffs patent challenge," dated ~March 26, 2011) documents an active dispute over exactly this patent:

• Licensing entity / likely plaintiff side: Zip-Flyer, LLC of New York City (owner Shawn Lerner), which claimed a "lifetime, exclusive license" to Patent No. 6,666,773 ("Downhill Zip Line Thrill Ride System," issued Dec. 23, 2003).
• Counsel for Zip-Flyer: Charles L. Roberts, Workman Nydegger (Utah IP firm).
• Counterparty / likely defendant side: Terra‑Nova LLC, the Utah maker of the "ZipTour" system, owned by Eric Cylvick (also of ZipHoldings LLC / ZipRider). Cylvick asserted he invented and patented the disputed brake technology and that Zip‑Flyer was the infringer.
• Subject matter of the dispute: the friction brake system for zip lines.
• The article states Lerner acknowledged "a current legal battle between his firm and Terra‑Nova LLC," and that Zip‑Flyer had sent infringement/threat letters to multiple Terra‑Nova/ZipTour customers (e.g., Gunstock Mountain Resort, New Hampshire).

This corroborates an inter‑party patent fight over the '773 patent, consistent with the Utah case listed in §1, but I cannot confirm that 2:10-cv-01031 is captioned Zip‑Flyer, LLC v. Terra‑Nova LLC (or the reverse) without the docket.

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3. Negative findings (matters NOT found)

• No PTAB / IPR / PGR proceedings for US 6,666,773 appeared in the Unified Patents IPR filing lists, PTAB document sets, or other results I retrieved.
• No CAFC appeal captioned to this patent number appeared in results.
• Note: several search hits referenced other patents (e.g., 6,842,677 "Vehicle Interface Technologies"; 7,819,066 "Zipline Trolley" in Skyline Zipline Global, LLC; an unrelated NZ company no. 6666773). These are distinct identifiers and are not litigation involving US 6,666,773. I have excluded them per your instruction not to conflate similar numbers.

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4. Practical/legal note

The '773 patent is recorded as "Expired – Lifetime," with anticipated expiration 2023‑03‑10. Even if the 2010 Utah action (or any enforcement campaign) once existed, no patent rights remain to assert today, so no active litigation on the '773 patent is expected.

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Bottom line

• Known litigation: Yes — one case is listed in the patent's record: D. Utah, No. 2:10-cv-01031, with the dispute over the '773 zip-line brake technology corroborated by 2011 press coverage involving Zip‑Flyer, LLC (exclusive licensee) and Terra‑Nova LLC / ZipHoldings / Eric Cylvick.
• Unconfirmed: the formal caption, precise filing date, and final disposition. If you need these confirmed, I recommend pulling the 2:10-cv-01031 docket via PACER and the Unified Patents case page directly.

I'll verify the structured ODP result against public sources before reporting.

Search results so far are irrelevant noise. Let me run targeted queries against PTAB dockets and the related litigation.

PTAB proceedings on file

Canonical source: USPTO Open Data Portal (ODP) — returns zero AIA trial proceedings for US 6,666,773. I independently ran web searches against PTAB dockets, Google Patents' litigation/citation tables, and third-party litigation databases. Nothing surfaced: no IPR, PGR, or CBM number naming this patent, and no PTAB decision citing it as the challenged patent. I am reporting the absence rather than inferring proceedings from the patent's citation trail (the many "Cited By" entries are later zip-line patents, not challenges to this one).

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Proceedings overview

Total AIA trial proceedings on file: 0 (0 active / 0 claims invalidated / 0 claims sustained / 0 settled / 0 institution denied). The only adversarial history in the record is a district-court action, and it never produced a PTAB filing. Practically, this means all 20 claims of US 6,666,773 stand as issued and untested — but they also expired on 2023-03-10, so the defensive question today is less "how do I kill these claims" than "is there any live assertion left to defend against."

A defendant receiving a demand letter citing this patent should treat the expiration date as the lead argument, not invalidity art. There is no IPR record to cite, no estoppel to inherit, and no claim-level disposition to quote.

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No proceedings to detail

There are no proceeding entries to render in the per-proceeding format requested (no {PROCEEDING_NUMBER}, no petitioner, no panel, no FWD). I will not manufacture a docket number or a panel — the instruction not to invent proceeding numbers governs here.

Related adversarial history (district court, not PTAB)

• Case: Zipholdings, LLC et al. v. Zip-Flyer et al., No. 2:10-cv-01031, D. Utah
• Filed: 2010-10-18
• Status (as reported by third-party dockets): Closed
• Patents asserted: the docket index shows '773 among a set including '752, '207, '367, '155, '099 — i.e., a multi-patent campaign in which US 6,666,773 was one of several asserted patents, not the sole focus.
• PTAB outcome: none. This case is the origin of the Google Patents "Utah District Court / 2:10-cv-01031" litigation flag on the patent page. No IPR petition was filed against '773 during or after that case.
• Note on litigation posture: Zip-Flyer is an operating company defendant, and the Google Patents assignee field shows the patent as held by an Individual (inventor Michael Troy Richardson) — consistent with an inventor-owned patent asserted alongside the Zipholdings portfolio. I did not find a public settlement term sheet; the case closed without a reported claim construction or invalidity judgment on '773 that I could verify.

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Strategic summary

Claim status: 1–20 all UNTESTED and, on the record, all SUSTAINED-by-default. No independent claim (1, 9, 15) has been canceled. No dependent claim has been canceled. There is no post-grant narrowing whatsoever: the claim set you would face is the set that issued on 2003-12-23, subject only to a Certificate of Correction recorded 2019-05-21 (the CC legal event in the file). A defendant should review that certificate — correction certificates typically fix typographical or claim-numbering errors and occasionally alter claim scope in ways that matter, and it has never been litigated.

The expiration date dwarfs the PTAB picture. The file shows "Anticipated expiration: 2023-03-10" and a final legal-status of "Expired - Lifetime." Maintenance fees were paid (year 4 on 2009-06-23, year 8 on 2011-12-21, year 12 on 2015-02-02 — all with surcharges), so the patent ran its full 20-year term rather than lapsing early; there was a reinstatement episode in 2008 after a maintenance-fee lapse. The consequence for a defendant: infringement liability for conduct after 2023-03-10 is essentially foreclosed, damages are limited to the pre-expiration window, and there is a six-year § 286 bar cutting into that window. Any demand letter asserting '773 today should be interrogated for whether it identifies pre-2023 accused conduct at all.

Estoppel landscape — § 315(e)(2): there is nothing to inherit, and nothing to fear. Because no IPR/PGR was ever instituted, no petitioner is estopped, and no defendant is buying into an existing estoppel record. That cuts both ways: (a) you face no adverse FWD holding any claim patentable over specific art, so you are not fighting a "patent survived IPR" narrative; but (b) you also get no free invalidity ruling to ride. If a live pre-expiration damages theory somehow exists, you would be litigating invalidity from scratch in district court under §§ 102/103/112, with the nine examiner-cited references (US 1,571,096; 1,859,180; 3,070,035; 3,218,988; 4,062,293; 4,934,277; 5,224,425; 5,904,099; 5,853,331) as your starting point — plus the inventor's own admissions in the specification about the Costa Rican single-groove nylon-pulley trolley, which is candid prior-art discussion that a § 103 obviousness theory could exploit.

Pattern signals. (1) No serial petitioner — no party ever filed even one IPR against '773, let alone multiple. (2) No PTAB appeal history for this patent — nothing to appeal, so no CAFC docket exists for it. (3) No defensive aggregator — Unified Patents appears in the litigation data as the source of the D. Utah case record ("Unified Patents Litigation Data" crowd-sourced the flag), not as a petitioner; it did not challenge '773. (4) The patent family stayed active after expiration — the same inventor, Michael Troy Richardson, appears as assignee on later US 11,772,684 B2 ("Zipline trolley," granted 2023-10-03) and on US 2023/0382437 A1 ("Zipline spring segment," published 2023-11-30), both listed in the '773 "Cited By" set and stemming from a 2017-04-20 priority date. There is also a continuation-in-part child of '773: US 10/745,742 → US 2004/0198502 A1, and a same-family US 8,424,460 B2 ("Trolley for downhill zip line thrill ride"). If you are being asserted against, confirm which patent number is actually in the demand — a letter waving '773 may really be aimed at the newer Richardson trolley/spring-segment family, which is where any enforceable life remains.

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Recommended next steps

1. Check for the 2019 correction certificate first. The CC event (2019-05-21) is the only claim-affecting post-grant event of record. Pull it from the USPTO Patent Center for US 6,666,773 and diff the claims. Any pre-suit analysis that relies on the printed claims without accounting for the certificate is unreliable.
2. No PTAB precedent to invoke. There is no FWD to link to, no E2E trial record, and no CourtListener opinion for this patent. Instruct outside counsel not to search for one — the correct statement to a court is affirmative: "No AIA trial proceeding has ever been instituted against US 6,666,773." Verify that statement's currency at PTAB E2E (https://ptacts.uspto.gov/ptab/) and the PATENTS End-to-End docket before filing it, since the ODP ingest you provided may lag newly-filed petitions.
3. Lead with expiration, not invalidity. US 6,666,773 expired 2023-03-10. Demand infringement discovery scoped to conduct before that date; apply the § 286 six-year bar to reach the 2017-2023-03-10 window and no further. Also confirm whether the patent owner is really asserting the '773 claims or the later '684 / spring-segment family — the strategic response changes completely depending on the answer.
4. If pre-expiration damages are genuinely on the table, the invalidity record is virgin. No § 315(e)(2) estoppel constrains you, no petitioner has already spent the best art. Start from the nine examiner citations above and the applicant's own admitted Costa Rican prior art, and consider a § 112(a) written-description attack on the "lever arm adjustment bracket" / pressure-adjustment mechanical relationship in claim 1, which the specification describes functionally ("the closer… the greater the maximum speed") rather than in structural terms.
5. Do not characterize silence as validation. A 20-year-old, expired, inventor-owned patent that drew zero IPRs is a weak candidate for aggressive assertion. The absence of PTAB activity here is a function of low commercial stakes plus expiration, not of a hardened claim set — but it does mean you have no free kill shot, and you should price the defense accordingly.

I'll research the assignment record for US 6666773 before writing the analysis.

Ownership & Assignment Analysis — US 666,6773

Scope note / data limitation: I was able to retrieve the full authoritative patent document (Google Patents, fetched 2026-09-24) and external litigation/press records, but I was not able to open the USPTO Assignment Center (assignmentcenter.uspto.gov) or the Assignment Search API directly in this session to pull reel/frame images. The findings below therefore rest on (a) the legal-events block of the patent record itself, and (b) litigation and press records. I flag every point where a reel/frame would be required but could not be obtained. I have not invented any reel/frame numbers.

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Inventors

Unusual-pattern check: The classic "all inventors leave the assignee within 12 months" fire-sale tell is not applicable — there is only one inventor and there was never a corporate assignee to leave. The notable pattern instead is inventor–licensee entwinement: Richardson later becomes a co-inventor with Lerner (Zip-Flyer's principal) on the '460 patent, which is the opposite of a clean inventor-to-NPE handoff.

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Original assignee

• Named assignee on the issued patent: none. Google Patents records Original Assignee = "Individual" and Current Assignee = "Individual" (with the site's own caveat that the listed assignees may be inaccurate). The maintenance-fee petition (2008-12-06) is recorded with "ENTITY STATUS OF PATENT OWNER: SMALL ENTITY," consistent with individual/small-entity ownership throughout.
• Product embodying the claims: Nothing in the record shows Richardson manufactured or sold a product. The system described in the specification was actually built at Park City, Utah by Terra-Nova of Utah LLC / ZipHoldings LLC (Eric S. Cylvick) — a different party who publicly disputed Richardson's inventorship, calling the patent "fraudulent." So the operating product in commerce was made by a third party, not the patent owner.
• Current status: No corporate status to report. The patent expired 2023-03-10 (anticipated expiration) and is now Expired – Lifetime. The individual owner's current status is not a matter of public record in this material.

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Assignment timeline

The provided USPTO/Google Patents legal-events record for US 666,6773 contains NO recorded assignments. The complete event list is maintenance-fee and post-grant administration only:

• 2007-07-05 REMI (maintenance fee reminder)
• 2007-12-23 REIN / 2008-02-12 FP (lapse)
• 2008-12-06 FEPP; 2009-06-22 PRDP (reinstatement)
• 2009-06-23 FPAY + SULP (4th-year fee, late)
• 2011-08-01 REMI; 2011-12-21 FPAY + SULP (8th-year fee, late)
• 2015-02-02 FPAY (12th-year fee)
• 2019-05-21 CC (certificate of correction)

There is no Assignment, Security Agreement, Merger, Change of Name, License, or Release event of record. I could not obtain a reel/frame for any conveyance, and I will not fabricate one. Per the operating rules, this is itself the finding: the recorded chain of title never left Michael Troy Richardson as an individual.

Critical caveat — extra-record evidence of a conveyance that was apparently never recorded as an assignment: Press reporting (Fosters Daily Democrat, "Gunstock rebuffs patent challenge," 2011-03-26) states that Zip-Flyer, LLC (New York, NY), owned by Shawn Lerner, held a "lifetime, exclusive license" to the '773 patent, and that Lerner "owns a licensing company which bought Richardson's patent." Zip-Flyer, through attorney Charles L. Roberts of Workman Nydegger (Utah), sent infringement demand letters to Terra-Nova/ZipHoldings customers. If that transaction was recorded at all, it would appear as a License (not an Assignment) — and it does not surface in the legal-events block. No reel/frame could be verified.

Litigation of record (not an assignment): Zipholdings et al v. Cylvick et al / Zip-Flyer et al, 2:10-cv-01031, D. Utah, filed 2010-10-18 (Judge David Sam). Plaintiffs: ZipHoldings, Terra-Nova of Utah, Eric S. Cylvick. Defendants: Zip-Flyer, Joseph Patrick Hally, Michael Troy Richardson. The '773 patent is among the patents at issue. This is a two-front dispute in which Cylvick's companies sued Richardson/Zip-Flyer while Zip-Flyer asserted the '773 patent against Terra-Nova's customer base.

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Timeline diagram

timeline
    title Ownership of US 6666773
    2003 : Richardson files app 10/385903
         : Patent 6666773 issues to Richardson
         : CIP 10/745742 filed
    2008 : Patent lapses for unpaid fee
    2009 : Patent reinstated
    2010 : Zipholdings sues Zip-Flyer and Richardson in D Utah
    2011 : Zip-Flyer sends infringement letters to customers
    2013 : Richardson and Lerner patent 8424460 issues
    2023 : Patent term expires

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NPE / troll-pattern signals

Assessed on the best available evidence. Because the recorded chain contains no assignments, most signals can only be called at "unclear" or "not present" — I have not upgraded any of them on names alone.

Counter-indicators worth recording: (i) the owner paid its own maintenance fees late and repeatedly, with a lapse-and-reinstatement in 2007–2009 and a surcharge in 2011 — behavior typical of a cash-constrained individual, not a funded assertion vehicle; (ii) the plaintiff with which the inventor ended up aligned (Zip-Flyer) was the defendant in the 2010 D. Utah action brought by ZipHoldings/Cylvick; and (iii) the inventor later co-patented with the licensee's principal, indicating a continuing substantive role rather than an arm's-length fire-sale.

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Verdict

Insufficient data.

The USPTO legal-events record for US 666,6773 contains no recorded assignments at all — only maintenance-fee, reinstatement, and certificate-of-correction events (2007-07-05 through 2019-05-21) — and the patent is listed with Original and Current Assignee = "Individual." Under the rubric, "no records, or only the original assignment" is the definition of Insufficient data, and I will not manufacture a reel/frame to force a stronger call. The only NPE-relevant material is extra-record: 2011 press reporting that Zip-Flyer, LLC (a Shawn Lerner licensing entity) held a "lifetime, exclusive license" to the '773 patent and asserted it against Terra-Nova/ZipHoldings customers, followed by the 2010-10-18 D. Utah litigation (2:10-cv-01031) in which Zip-Flyer and Richardson were named defendants. That is a non-practicing assertion posture worth monitoring, but because the conveyance was apparently a license that was not recorded as an assignment, it cannot be verified at reel/frame level and does not convert the call to NPE — moderate or high confidence.

Verify at: USPTO Assignment Center — https://assignmentcenter.uspto.gov/ (search patent number 6666773) and https://assignment.uspto.gov/patent/index.html. Cross-check docket 2:10-cv-01031 via https://dockets.justia.com/docket/utah/utdce/2:2010cv01031/77572.

I'll search the USPTO database for this specific patent and then examine each cited prior-art reference.

Let me search for details on each of the nine cited prior-art references.

I've reached my search-step limit, so I'll compile the analysis from the authoritative patent text (supplied) plus the targeted lookups I completed. I've noted verification status for each reference.

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Prior-Art Analysis — US 6,666,773 B1 ("Downhill zip line thrill ride system")

A. Confirmation of the target patent (USPTO / public record)

The bibliographic record I retrieved (Google Patents, mirroring the USPTO/EPO DocDB data) matches the authoritative text supplied earlier. Caveat: I did not open USPTO PatentCenter/PAIR directly within my step budget; the record above is corroborated across Google Patents and the CIP publication US 2004/0198502 A1, which states on its face that it "is a continuation-in-part of application Ser. No. 10/385,903, which was filed on Mar. 10, 2003 and issued on Dec. 23, 2003 as U.S. Pat. No. 6,666,773." I found no result conflating this with any similar number (e.g., the NZ entity "no. 6666773" or US 6,842,677), and I have not treated any of those as this patent.

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B. The cited prior art — the nine "Patent Citations" of US 6,666,773

All nine references are listed on the face of the patent as cited by the examiner (marked * in the authoritative text). Because the '773 application was filed 2003-03-10, every one of these references (all issued 1926–1999) qualifies as prior art under pre-AIA 35 U.S.C. § 102(b) — patents/printed publications more than one year before the US filing date. They are all the same field (suspended-cable trolleys / amusement braking), so they are "analogous art."

Important overall finding: None of the nine references, alone, discloses the distinctive combination claimed in the '773 patent — namely (i) the tubular brake retainer with a full-length longitudinal slit, (ii) the cylindrical abrasion-resistant brake seated concentrically and rotatably inside the retainer, with a longitudinal groove, that is rotated arcuately to lock the cable in, (iii) the pulley spaced from the retainer by an at-least-cable-diameter gap, and (iv) the fore/aft-positionable lever-arm adjustment bracket that sets brake-to-cable pressure. Accordingly, on the record I have, none is anticipatory under § 102 as to any of claims 1–20; they are best characterized as "A" (background) art bearing on the preamble elements (towers, suspended cable, a pulley-riding trolley). My per-reference assessment follows.

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1. US 1,571,096 A — "Escape for derricks"

• Full citation: Rambin, Louis Garland, US 1,571,096 A. Filed 1925-09-30; published/issued 1926-01-26.
• Description (from title/field; full spec not independently retrieved): A derrick-personnel escape apparatus — a sling/carrier that travels down an inclined cable. The earliest and most generic "travel along a suspended line" reference in the list.
• § 102 assessment: Touches only the generic notion of a carrier riding a cable. Does not anticipate any claim. No brake retainer, no rotatable brake, no pulley gap, no lever-arm bracket. Relevance: general background only.

2. US 1,859,180 A — "Trolley for bathing beaches"

• Full citation: Thiel, Henry A., US 1,859,180 A. Filed 1929-11-11; issued 1932-05-17.
• Description: A trolley that rides a suspended cable (e.g., a beach/water line). Discloses the basic "trolley on a suspended cable" structure.
• § 102 assessment: Bears only on the preamble of claims 1/9/15 (a trolley movable along a suspended cable). Not anticipatory. No brake retainer/rotatable-brake/lever-arm features are disclosed.

3. US 3,070,035 A — "Children's amusement and exercising apparatus"

• Full citation: Russo, Nichola P., US 3,070,035 A. Filed 1962-01-02; issued 1962-12-25.
• Description: A children's trolley/pulley ride along a suspended line — a pulley-equipped carrier on a cable. Note this reference is itself cited by US 4,062,293 in the same list (see #5), confirming its role as early trolley art.
• § 102 assessment: Discloses a pulley riding a suspended cable (relevant to the "pulley with a circumferential groove riding the upper surface of the cable" language of claims 1/9/15), but none of the brake-lock or adjustment limitations. Not anticipatory.

4. US 3,218,988 A — "Mono cable transporting device"

• Full citation: Theophile, Gaston, US 3,218,988 A. Filed 1961-11-18; issued 1965-11-23.
• Description: A single-cable (mono-cable) aerial transport in which a carriage/trolley runs on one suspended cable. Standard mono-cable tramway art.
• § 102 assessment: General transport-trolley art; addresses the suspended-cable carriage concept only. Does not anticipate any of claims 1–20.

5. US 4,062,293 A — "Trolley ride apparatus" (⚠ most structurally relevant of the nine)

• Full citation: Davis, Joseph I.; assignee Davis-Grabowski, Inc., US 4,062,293 A. Filed 1976-03-08; issued 1977-12-13.
• Description (verified from the patent PDF and Google Patents): A trolley ride for sliding along a wire stretched between two uprights, having a pair of identically molded plastic side members bolted together with a pair of horizontally aligned pulleys rotatably mounted therebetween; each side member has a tubular handle reinforced by a pipe. The pulley has a peripheral groove that receives the wire/cable. This is the closest structural analogue in the list to a "frame + pulley-riding-on-cable" trolley.
• § 102 assessment: Potentially relevant to the preamble + pulley elements of claims 1, 8, 9, and 15 (frame; pulley with circumferential groove riding the cable; cable between two supports). It does not disclose: the tubular brake retainer with longitudinal slit; the cylindrical rotatable lock-in brake; the cable-diameter gap requirement; or the fore/aft lever-arm adjustment bracket. Cannot anticipate any claim alone, and would not render claims 1–20 obvious by itself given the missing brake/adjustment architecture. Classified as "A"-type background art.

6. US 4,934,277 A — "Mobile aerial rapid rescue system"

• Full citation: assignee Evacuation Systems, Inc., US 4,934,277 A. Filed 1987-07-02; issued 1990-06-19.
• Description (from title/field; full spec not independently retrieved): A mobile zip-line/rescue system deploying a trolley on a tensioned cable for evacuating people — the same rescue-zip-line lineage the '773 Background expressly acknowledges ("extensively used for rescue work on ski lift equipment").
• § 102 assessment: Reinforces that trolley-on-suspended-cable rescue systems were known; no teaching of the claimed lock-in brake or the pressure-adjustment bracket. Not anticipatory.

7. US 5,224,425 A — "Cable skydiving" (⚠ closest to the overall system)

• Full citation: Remington, Bruce A., US 5,224,425 A. Filed 1991-06-12; issued 1993-07-06.
• Description (verified from the specification text retrieved): A gravity thrill ride using a main cable suspended between top and bottom cable support towers/platforms, on which pulley-block cars descend; the specification expressly discusses friction between the pulleys and cable as the braking mechanism, rider support, and return of cars to the top. This is the nearest reference to the "thrill ride" system framing (towers + suspended cable + descending trolley + friction control).
• § 102 assessment: Potentially relevant to the claims 1/9/15 preamble (upper and lower support towers; cable suspended therebetween; trolley movable along the cable) and to the general friction-braking concept. However, it discloses no tubular brake retainer, no concentric rotatable locking brake, no cable-diameter pulley gap limitation, and no lever-arm adjustment bracket. Not anticipatory of any claim.

8. US 5,853,331 A — "Amusement ride" (⚠ terminal-braking-adjacent)

• Full citation: assignee Bungee Japan, Inc., US 5,853,331 A. Filed 1998-05-06; issued 1998-12-29.
• Description (from title/field; full specification not independently retrieved in this session): An amusement ride (Bungee Japan) involving a suspended/gravity-propelled rider. It appears in the citation list and is also cited in later zip-line art; I could not retrieve its full text here, so my statement of its disclosure is limited to its title/field and I flag that limitation explicitly.
• § 102 assessment: General amusement-ride art; on the information available, it does not disclose the claimed rotatable lock-in brake retainer, the pulley gap, or the fore/aft adjustment bracket. Not anticipatory of any claim. (If a fuller spec is needed, I recommend pulling the full document — see caveats.)

9. US 5,904,099 A — "Cushioned braking system for a monorail trolley" (⚠ braking-art closest)

• Full citation: Danneker, Edward M.; assignee Playworld Systems, Inc., US 5,904,099 A. Filed 1997-08-15; issued 1999-05-18.
• Description (verified from the patent and Google Patents): A monorail trolley with a cushioned braking system comprising a double-ended air cylinder with pistons and a spring assembly that engages stops at each end of the track to decelerate the trolley gradually (child-playground amusement). The spring biases the pistons to a reference position; vent means control airflow.
• § 102 assessment: This is the closest reference to the terminal-deceleration concept recited in claim 7 (spring-absorbing end-of-ride braking) — but it is structurally different: it is a monorail track with air-cylinder + stop braking, not a cable-mounted V-shaped trap sliding against coil springs on weighted bushings. It therefore does not anticipate claim 7 (or any other claim) and, at most, is "A"-type art. It also has no brake retainer, rotatable brake, pulley gap, or lever-arm adjustment bracket.

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C. Consolidated § 102 table

Bottom line on the nine citations: every one is early-to-mid background art in the same field. The patent's novelty resides in the rotatable, groove-aligned, lock-in tubular brake retainer, the cable-diameter pulley gap, and the fore/aft pressure-adjustment bracket — none of which any cited reference discloses. So the citations are supportive "A" art, not anticipation.

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D. What the more legally significant prior art is (flagging beyond the citation list)

For completeness — and because the task is to find the most relevant prior art — the references cited against the '773 patent by later examiners (the "Cited By" set, which are later than '773 and thus not prior art to it) and the co-pending/family art are worth distinguishing, so they are not confused with § 102 art against '773:

• US 2004/0198502 A1 (Richardson) — the continuation-in-part of '773 itself, published 2004-10-07. It is family, not prior art.
• US 8,424,460 B2 (Lerner & Richardson) and US 2012/0160122 A1 — later Lerner/Richardson trolley applications (side-plate frame, gallery shackle). These post-date '773 and share the same inventor lineage; they are not § 102 art against '773.
• The "Cited By" list (59+ entries, e.g., Cylvick's trolley-brake/arrester patents, Ziptrek, Skyline Zipline) is after-arising art — relevant to the validity of the later patents, not to '773.

I did not find any reference in the citation list resembling the '773 patent's signature rotatable slit-tube locking brake, which is consistent with the patent's allowance. Confirming the absence of such art would require a full-text search of CPC A63G 21/22 and F16D 63/008 — outside my remaining step budget.

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E. Verification caveats (per operating rules)

1. Number integrity: I treated "6666773" literally as US 6,666,773 B1 only. I did not merge results for US 6,842,677, US 5,904,099 (a cited reference, not the target), the NZ "6666773" entity, or any other similar identifier.
2. Descriptions: I directly verified the full text/abstract of US 4,062,293, US 5,904,099, and (partially) US 5,224,425. For US 1,571,096, US 1,859,180, US 3,070,035, US 3,218,988, US 4,934,277, and US 5,853,331, I relied on the citation data in the authoritative patent text plus field/title, and I did not retrieve each full specification — I flag this rather than guess at their internals. If you need claim-by-claim diligence on those six, pull their full documents (Google Patents/PatentCenter).
3. § 102 framing: My "potentially anticipates" column reflects my analysis that none of the nine are anticipatory; where I list claims, I mean the reference merely touches a preamble/element, which is the standard for "A"-type background art.
4. Statutory basis: All nine predate the 2003-03-10 filing by well over a year → § 102(b) (pre-AIA). If the CIP (US 10/745,742) or later family patents were separately challenged, the § 102/§ 103 analysis for those would differ (and would draw on the "Cited By" set), but that is beyond the '773 citation list you asked me to analyze.

Sources: Google Patents US6666773B1 (https://patents.google.com/patent/US6666773B1/en) and the authoritative full text supplied; US 2004/0198502 A1 PDF; US 4,062,293 (https://patents.google.com/patent/US4062293); US 5,904,099 (https://patents.google.com/patent/[US5904099A](/patent/US5904099A)/en); US 5,224,425 (https://uspto.report/patent/grant/[5,224,425](/patent/5224425)).

I'll pull what I can on the nine examiner-cited references so the § 103 analysis is grounded in actual reference disclosures rather than titles alone.

Good — US4934277 is highly relevant (lever-arm brake with weight-dependent positioning). Let me get the remaining examiner-cited references.

Obviousness Analysis — US 6,666,773 B1 under 35 U.S.C. § 103

Building on the previously generated sections. Bibliographic data, claim summaries, and the litigation history are not repeated here; this section addresses validity over prior art only.

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1. Governing framework and evidentiary posture

Statute. US 6,666,773 was filed 2003‑03‑10 and issued 2003‑12‑23, so it is governed by pre‑AIA § 102/§ 103(a). KSR Int'l Co. v. Teleflex Inc., 550 U.S. 398 (2007), applies to pre‑AIA § 103 and controls the analysis below. The Graham v. John Deere factors (scope/content of the prior art; differences; level of ordinary skill; secondary considerations) frame the inquiry.

Level of ordinary skill (PHOSITA). For a 2003 filing date, a person of ordinary skill in this art is most plausibly a mechanical engineer (B.S.M.E. or equivalent) with roughly two to four years of experience designing suspended‑cable transport, aerial tramway, or amusement‑ride hardware, or a technician of comparable practical experience in ski‑lift evacuation trolleys and "zip line" hardware. The art is mechanical, mature, and highly predictable; virtually every element is a rotating or sliding mechanical part whose behavior is readily calculable.

Evidentiary limitation — please read as a caveat, not boilerplate. The nine references cited on the face of the '773 patent were furnished to me only as bibliographic entries (number, inventor, assignee, title, date). I was able to retrieve and read substantive disclosure for three of them — US 4,934,277; US 4,062,293; and US 5,904,099 — plus partial content for US 5,224,425. I was not able to retrieve the disclosures of US 1,571,096 (Rambin); US 1,859,180 (Thiel); US 3,070,035 (Russo); US 3,218,988 (Théophile); or US 5,853,331 (Bungee Japan) before reaching my search limit. Where I rely on a reference I did not read, I say so explicitly and mark the inference as unverified. I have not fabricated any reference disclosure.

A preliminary point on the "Cited By" and "Similar Documents" lists. The ~105 third‑party citations and the "Similar Documents" list on the Google Patents page are not available as § 103 prior art against the issued '773 claims. The earliest priority date in the entire "Cited By" listing is 2004‑07‑02 (US 7,381,137, Ziptrek Ecotours), which post‑dates the '773's 2003‑03‑10 filing by well over a year. None of them qualify under § 102(a), (b), or (e). They are useful only as context — evidence of the state of the art after the '773 and of the commercial activity it provoked.

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2. The prior art of record, and what each reference contributes

Admitted prior art in the '773 specification itself. The specification's Background admits: (i) "Transport systems involving a trolley slidable along a suspended length of cable have been known in the art for many years"; (ii) the Spring Swings, Inc. "Fun Ride Deluxe" kit with a "super tough" double‑pulley plastic trolley running on stranded steel aircraft cable; and (iii) the Costa Rican zip line with a trolley having "a single deep‑groove nylon pulley riding on the suspended cable," where the rider brakes by twisting the trolley so that "the flanges of the pulley rub against the cable and generate friction," dissipating kinetic energy as heat. These are binding admissions for § 103 purposes and are, in my view, the single most damaging "reference" against several dependent claims.

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3. Element‑by‑element mapping of independent claim 1

The honest bottom line: eight of the nine recited elements of claim 1 are squarely in the art. The claim's patentable weight — and the reason the examiner allowed it — sits in the slitted tubular retainer + rotatable concentric grooved brake that captures the cable by rotation. Any § 103 case must win on that element. Accordingly, I organize the grounds below in ascending order of difficulty, and I am explicit about which ground I believe fails.

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4. Ground 1 — Claims 2, 16 (brake/bumper material): obvious as a matter of law

This is the easiest ground and does not require any of the unread references.

• US 4,934,277 teaches a brake shoe pressed against a cable; the selection of the shoe's friction material is a routine matter of engineering choice within the known class of friction polymers.
• The '773 specification's own admissions disclose a zip‑line trolley whose brake is a nylon pulley rubbing a steel cable (Costa Rica), and a trolley with a plastic pulley (Spring Swings).
• Claims 2 and 16 recite the material as a Markush selection: "Teflon®, nylon, high‑density polyethylene, and composites."

Rationale (MPEP 2143(B) — simple substitution of a known element for a known purpose): Substituting one known abrasion‑resistant polymer for another in a friction‑brake application, where the specification itself recites three of the four species as interchangeable alternatives and asserts no unexpected result, is the paradigm of an obvious substitution. Anticipating the objection that a specific coefficient of friction might matter: the '773 specification asserts no criticality, no unexpected result, and no data. Absent a showing of unexpected results, "the selection of a known material for a known property" is routine. The "composites" catch‑all is broader still and adds nothing.

Assessment: claims 2 and 16 are invalid under § 103 over the admitted prior art alone, or over US 4,934,277 in view of the admitted art.

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5. Ground 2 — Claim 6 (I‑beam frame from metal plate stock) and claims 3–5, 12–14, 18–20 (arcuate slit / bolt / locking slit): obvious

Claim 6. Recites only a frame of generally I‑beam cross‑section fabricated from metal plate stock. US 4,934,277 discloses a plate frame with a "T‑shaped gusset (38)" welded to a plate to stiffen it — the same structural concept one step away from an I‑section. Choosing an I‑section to maximize bending stiffness per unit mass is elementary strength‑of‑materials practice, not invention. MPEP 2143(F) (design incentives) and 2144.04 (design choice) both apply. This claim is very weak.

Claims 3–5 / 12–14 / 18–20 (arcuate slit of 90–120°, bolt through the arcuate slit limiting rotation, arcuate slit intersecting a locking longitudinal slit). Three points:

1. A bolt riding in an arcuate slot to bound rotation between two angular limits is one of the oldest mechanical expedients in existence, and US 4,934,277 itself uses bolt 36 received in one of a plurality of bores 42 and secured by nut 37 to fix a pivoted lever arm at a selected position — the bolt‑through‑hole locking principle.
2. The recitation of a 90°–120° range, with a preferred "about 105 degrees," is a pure range optimization. The specification offers no data, no criticality, and no unexpected result; it simply states the range is "presently deemed to be" preferred. Under In re Aller and In re Boesch, optimizing a working range for a known mechanism, absent a showing of criticality, is within the ordinary skill of the art. Note also the internal tension I flagged in the earlier section — the arc must be at least enough to swing the brake groove from alignment with the slit to facing upward (roughly 90°–120° of geometry is dictated by the cable‑capture kinematics, not chosen inventively), so the claimed range is essentially the only workable one and is therefore an obvious range to try.
3. The "locking longitudinal slit [intersecting] the arcuate slit" is simply a bayonet‑slot / J‑slot lock — the classic twist‑and‑capture mechanism of bayonet lamp mounts, camera mounts, and, more to the point, any number of rotary catches. Its function is to convert arcuate motion into a positive axial lock, which is exactly its known function.

Assessment: claims 3–5, 6, and 12–14 and 18–20 are invalid under § 103. Claim 6 in particular is a design‑choice claim that would not survive a well‑pleaded § 103 challenge.

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6. Ground 3 — Claim 10 (slot + linear aperture array + locking pin): essentially anticipated in substance by US 4,934,277

Claim 10 recites: a longitudinal adjustment slot to which the bracket is slidably affixed; a linear array of evenly spaced apertures beneath and parallel to the slot; and a removable locking pin securing the bracket to one of the apertures.

US 4,934,277 discloses:

"A plurality of vertically spaced apart holes or bores 42 extend through the vertical gusset and through the plate 20 to accommodate the bolt 36. The bolt 36 may be selectively housed in one of the bores 42 and secured in place by nut 37."

The only difference is that the '773 claim separates the sliding function (slot) from the locking function (aperture array + pin), whereas US 4,934,277 uses the same bores for both. That is a difference in part count, not in function: both accomplish "grant the lever arm a finite set of selectable positions along a line, and lock it there non‑destructively." A PHOSITA seeking to make the adjustment continuously slidable and positively locked, or seeking to speed up the adjustment, would combine a slot with a locking aperture array as a matter of obvious mechanical design. If anything, US 4,934,277's single‑bolt‑in‑one‑of‑a‑series‑of‑bores version is more elegant, and the '773 version is the obvious engineering embellishment.

Assessment: claim 10 is invalid under § 103 over US 4,934,277 (optionally combined with any of US 4,062,293 / US 5,904,099 for the trolley subcombination). This claim is the single strongest invalidity target in the patent, because the reference the examiner himself cited already contains the mechanism.

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7. Ground 4 — Claims 1, 9, 15, 11, 17 (the independent claims' lever‑arm element): the functional‑recitation problem

Note that claims 1, 9, and 15 recite the adjustment bracket functionally:

• Claim 1: "a lever arm adjustment bracket… being positionable fore and aft to adjust an amount of pressure between the bottom portion of the longitudinal groove and the lower surface of said cable."
• Claim 15: same language, with "the rider mounting bracket being positionable fore and aft…" — the antecedent‑basis defect I flagged in the earlier section (no "rider mounting bracket" is introduced; presumably meant to read "lever arm adjustment bracket." I have not verified whether the 2019‑05‑21 Certificate of Correction addressed this).

Two consequences:

1. MPEP 2114 / In re Schreiber: reciting the function of a structure that otherwise reads on the prior art does not distinguish the claim. US 4,934,277's lever arm does "adjust an amount of pressure" applied to the cable's underside by the person's weight, and is repositionable along a linear array of bores to change that pressure for a rider of different weight. If the argument is that the '773 bracket presses a grooved cylindrical brake rather than a shoe, then the claim is distinguished only by the brake‑retainer element of § 3 above, and the bracket element itself falls.
2. The functional phrasing is a § 112(b) vulnerability as well, but for § 103 purposes it means the bracket element should be treated as met by US 4,934,277.

Motivation to combine (Grounds 1–4). Under KSR, the motivation is supplied by (a) the same field of endeavor — cable‑suspended trolleys for carrying and decelerating a suspended person, whether for rescue, amusement, or recreation; (b) the same problem — controlling descent speed on a suspended cable without the rider having to improvise braking; (c) the '773 specification's own framing of the problem (the Costa Rican system where "the riders, themselves, must take responsibility for maintaining their descent speeds within a safe range, in order to avoid smashing into the lower cable support tower"); and (d) the predictability of the result — combining a friction lever‑arm brake (US 4,934,277) with an amusement trolley (US 4,062,293) and a tower‑to‑tower suspended cable (US 5,224,425) yields nothing more than the predictable sum of the three known functions. KSR: "if a technique has been used to improve one device, and a person of ordinary skill in the art would recognize that it would improve similar devices in the same way, using the technique is obvious."

So Grounds 1–4 dispose of claims 2, 3, 4, 5, 6, 10, 12, 13, 14, 16, 18, 19, and 20 — thirteen of the twenty claims — and they dispose of the lever‑arm element of claims 1, 9, 11, 15, and 17.

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8. Ground 5 — Claim 7 (terminal trap, slanted bumper nose, coil‑spring assemblies with weighted bushings): obvious, but the messiest combination

Claim 7 adds: a ramped V‑shaped trap slidably mounted on the cable near the lower tower; coil spring assemblies with weighted bushings at each end, concentrically on the cable between the trap and the lower tower; and a downwardly‑slanted frame nose with a polymeric bumper that the trap's internal ramp forces downward, thereby (i) increasing brake pressure and (ii) transferring momentum to the trap and accelerating the weighted bushings while compressing the springs.

Mapping:

• US 5,904,099 is the key reference: an amusement trolley carrying a terminal cushioned braking system engaged when the trolley "engage[s] a stop," in which the stop "begins to exert a force on the rod to oppose the force exerted by the momentum of the trolley," and in which a spring assembly (expressly plural springs, with a spacer between them) provides the cushioning. Its stated purpose — "to provide a cushioned halt of the trolley" without harm to the suspended rider — is identical to claim 7's stated purpose.
• US 4,934,277 supplies the conversion of the suspended rider's weight/momentum into downward brake‑engagement force via an angled lever arm, and the adjustable lever‑arm geometry — the same physical principle as a sloped ramp pushing the nose down to increase brake pressure.
• US 5,224,425 supplies the tower‑and‑platform termini where such a terminal arrester is located, and even a disembarking platform arrangement.
• The "weighted bushings" accelerated to absorb momentum are nothing more than an inertia/momentum‑transfer damper — the elementary mechanical analogue of the piston‑and‑spring energy absorber of US 5,904,099. Accelerating a mass to dissipate kinetic energy is basic mechanics; a PHOSITA choosing among "more springs," "a heavier stop mass," or "both" is choosing among a small, finite set of predictable energy‑absorption options. KSR supplies the rationale.

Motivation: the '773 specification states the objective itself and admits it is driven by pure risk management — "These features ensure that even if the pressure of the brake against the suspended cable is not properly adjusted before the ride begins, the rider will stop safely before reaching the end of the suspended cable." A safety‑driven design goal, pursued with known energy‑absorbing hardware (US 5,904,099) at known cable termini (US 5,224,425), is obvious. KSR: market forces and design needs provide the motivation.

Honest counter‑assessment: this is the weakest of my grounds. The specific architecture — a slidable trap on the cable, with coil springs concentrically threaded on the cable itself via weighted bushings, rather than a fixed stop on a rail as in US 5,904,099 — is a real structural difference, and I do not have a pre‑2003 reference that discloses a cable‑threaded spring stack. (The later US 9,669,319, ZipHoldings, 2014, discloses a cable‑threaded spring stack with impact spacers almost verbatim — but it post‑dates the '773 by more than a decade and is therefore not prior art. Its existence is, if anything, a § 102(f)/derivation curiosity in light of the Cylvick dispute, not a § 103 reference.) I would not assert claim 7 as clearly obvious on the record the examiner assembled; it is defensible. This is consistent with the earlier litigation summary's account of a rival inventorship claim over broadly this subject matter.

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9. Ground 6 — Claim 8 (method of installing the trolley on the cable): obvious

Claim 8 recites the installation sequence: rotate the brake so its groove aligns with the retainer slit → position the trolley below and oblique/perpendicular to the cable → elevate so the cable enters the gap → align so the cable enters the slit and groove and the pulley sits above the cable → seat the pulley → rotate the brake to lock.

This is a method of using the apparatus of claim 1, and every step is dictated by, and inherent in, the structure the anterior claims recite. Where the apparatus is obvious, a claim to the method of putting it on the cable adds nothing inventive. Independently, US 4,934,277 expressly touts that its device "can be easily attached to the cable," and US 4,062,293 shows a grooved‑pulley carrier that is simply lowered onto a stretched wire between uprights. If claim 8 survived at all, it would be on the strength of the brake‑retainer element — and it would be a § 112(b) written‑description/enablement problem too, since the sequence was added by amendment to describe a structure already claimed.

Assessment: claim 8 rises or falls with the brake‑retainer element and is otherwise obvious.

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10. The crux: the slitted tubular retainer with the rotatable concentric grooved brake (claims 1, 9, 11, 15, 17)

This is the only element on which the § 103 case is genuinely contestable, and I want to be candid about what I can and cannot support.

What I can argue.

1. Every sub‑element is old, and the combination is a predictable aggregation of known functions. A tube with an end‑to‑end side slit is a clip, a conduit with an access slot, or a shell bearing housing. A cylinder rotatable within a tube is a bushing/journal. A groove in a rotating member that traps a cable is a sheave groove (US 4,062,293, groove 27; US 4,934,277, groove 30). A grooved nylon body frictionally engaging a suspended cable to brake is admitted prior art (the Costa Rican trolley). Rotating a slitted outer shell relative to a grooved inner body to capture a line is the bayonet/rotary‑lock principle. The claim does no more than arrange these known parts to perform their known functions — the Anderson's‑Black Rock / KSR formulation.
2. The problem itself points to a rotary solution. The '773 specification identifies the design requirement: the trolley must "quickly engage and disengage the cable" while also (a) remaining captive during the ride (the specification even describes a safety lock actuated by ride operator personnel to prevent removal until the landing point) and (b) braking against the cable. A PHOSITA told "make a trolley that snaps onto the cable from below and cannot come off, and that brakes on the cable" has a small, finite set of known options: a hinged/clam‑shell housing with a latch; a spring‑loaded gate (as in any snatch block); a pin‑and‑slot or bayonet rotary lock; or a threaded collar. Choosing the rotary‑lock option is KSR "obvious to try" territory — "a finite number of identified, predictable solutions."
3. The field's own convention is rotary engagement. Both US 4,062,293's and US 4,934,277's carriers are open‑bottomed and grooved, i.e., they attach by relative motion of the carrier and cable, and the '773 itself teaches that the trolley is disengaged by reversing the rotation. Rotation‑based engagement is thus the idiosyncratic attachment mode of this very art, not an import from elsewhere.
4. US 3,218,988 (Théophile), "Mono cable transporting device." A monocable ropeway carrier must have a housing that receives and grips a single haul rope, and such devices historically use a rope passage through the housing with a movable jaw. If — and this is expressly an unverified hypothesis, because I was unable to read the reference — US 3,218,988 discloses a housing with a rope‑receiving slot and a relatively movable rope‑engaging member, it would supply the missing element almost directly, and claims 1, 9, 11, 15, and 17 would fall in view of Théophile in combination with US 4,934,277 (lever‑arm brake) and US 4,062,293 (amusement trolley). I recommend pulling US 3,218,988, US 1,859,180 (Thiel), and US 5,853,331 before pressing any § 103 attack on the independent claims. Until then, Ground 4 above establishes obviousness as to the lever‑arm element only, and the independent claims are not clearly invalid.

What cuts the other way — and you should not ignore it.

• The examiner cited nine references, including three (US 4,934,277, US 4,062,293, US 5,904,099) that collectively teach a grooved cable‑riding trolley with a rider‑weight‑actuated, positionally adjustable lever‑arm friction brake and a terminal spring‑damped arrest — and still allowed the claims. The most plausible reading is that the examiner found the slitted retainer / rotating lock‑in brake absent from the art of record. That presumption of administrative correctness should be respected until a specific reference is found.
• I found no reference, in the nine cited or in the 105 third‑party citations, that discloses the slitted tubular retainer with a concentric rotatable grooved brake, in the pre‑2003 window. That is a meaningful negative for a § 103 attack, though it is not dispositive (KSR does not require a reference teaching the claimed combination, only a reason to combine known elements).

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11. Secondary considerations

The record before me supplies almost no nexus‑bearing objective evidence, and what exists cuts toward obviousness.

• Commercial success. The Park City, Utah installation is real and was commercially significant; the '773 specification describes it and the earlier sections of this analysis credit the ride's prominence. But there is no evidence in the record of a nexus between that success and the specific claimed brake‑retainer geometry (as opposed to the ride's novelty as an amusement attraction, its location, or its marketing). Ormco Corp. v. Align Tech., 463 F.3d 1299 (Fed. Cir. 2006). Asserted without nexus, this evidence is entitled to little or no weight.
• Licensing. The 2011 press account (built on in the litigation section) indicates Zip‑Flyer, LLC held an exclusive license and pursued an enforcement campaign — including a § 112-style patent challenge by a rival, Gunstock/Terra‑Nova/ZipHoldings. A willingness of a licensee to take a license is some evidence of value, but a single exclusive license, without more, is generally de minimis secondary evidence. Iron Grip Barbell v. USA Sports, 392 F.3d 1317 (Fed. Cir. 2004).
• Copying / industry uptake. The extraordinarily large third‑party citation count (105) — including trolleys and braking systems from Cylvick/ZipHoldings, Skyline Zipline Global, Adventure Holdings, Ropes Courses, Darby Adventure Systems, TruBlue, and others — could be marshaled as evidence of recognition in the field (and of copying). I think it cuts the other way here, and a defendant would say so: an art in which a hundred independent actors converge on "a grooved friction brake on a suspended cable, actuated by the rider's weight, with a terminal arrester" within a decade is an art in which the claimed combination was the expected, predictable next step. That is exactly the KSR "finite number of identified, predictable solutions" rationale. Cf. In re Kahn, 441 F.3d 977 (Fed. Cir. 2006) (predictable results from a finite design space).
• Long‑felt need. The '773 specification itself frames the Costa Rican trolley's uncontrolled descent and premature pulley failure as a known problem. That framing supports a long‑felt need for speed control — but the solution it identifies (polymeric friction braking) was already in the admitted art. The need existed; the disclosed remedy was known.
• Unexpected results / criticality. None disclosed. The specification recites a 90°–120° arc ("preferred… about 105 degrees") and a brake material Markush without a single datum. Where a patent makes a range or material selection but discloses no criticality or surprising result, the "unexpected results" prong of secondary considerations is unavailable as a matter of course.

Finally, note the internal inconsistency I flagged earlier — the specification says the ride limits riders to "no more than about 55 m.p.h." in the Background but "no more than about 70 m.p.h." in the Preferred Embodiment (the same discrepancy exists as between the '773 and its CIP, US 2004/0198502 A1). This is not a § 103 point, but it is a credibility point a defendant would use if the patentee tried to argue any speed‑range limitation as a source of nonobviousness. No claim recites a speed.

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12. Disposition

Overall assessment. US 6,666,773 would not survive a serious § 103 challenge as to thirteen of its twenty claims — the entire material, geometry, frame, adjustment‑mechanism, and method periphery — on the examiner's own cited references, principally US 4,934,277 sealed together with US 4,062,293 and US 5,224,425, with US 5,904,099 supplying the terminal arrester. The independent claims' survival, and that of claim 7, rests on one mechanism (the slitted tubular retainer with the rotatable concentric grooved brake) and on one subsystem (the cable‑threaded spring/bushing trap). Whether those fall depends on references I was unable to read in this session — most importantly US 3,218,988 (Théophile), and secondarily US 1,859,180 (Thiel) and US 5,853,331 (Bungee Japan). I am not prepared to call claims 1, 9, 11, 15, and 17 obvious on the present record, and I would not represent that they are without first reading Théophile. If Théophile turns out to disclose a ropeway carrier housing with a rope‑receiving slot and a relatively rotatable rope‑engaging member, the entire patent becomes a straightforward pre‑AIA § 103 combination over its own cited art and its term of expired protection is academic.

Sources for reference disclosures: US4934277A; US4062293; US5904099A (including the USPTO full‑text PDF at patentimages.storage.googleapis.com); USPTO.report entry for 5,224,425; authoritative full text of US6666773B1 as supplied.