US 11022417

I'll verify the patent's current status and check for any litigation activity before summarizing.

Let me run a couple more targeted checks for litigation/docket activity.

US Patent 11,022,417 — Analyst Summary

Data source note: I could not reach USPTO PatentCenter/PAIR or the CAFC docket system directly from this session. The bibliographic and claim data below are taken from the authoritative full text of the patent supplied to me (Google Patents rendering of US11022417B2, fetched 2026‑09‑24), cross‑checked against secondary sources (Justia, Patents Encyclopedia, Taiwan TWI824505B family record, Google Patents family listing). Web searches for litigation and PTAB activity are reported at the end.

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1. Bibliographic data

Literal-identifier caution: the digit string "11022417" also appears as application number 11/022,417, which is the unrelated "Quick release arbor" application that issued as US 7,175,372. I have not conflated the two; everything below is for patent 11,022,417.

2. Abstract (verbatim)

"A tool, such as a tape measure, including a spring-based retraction system is shown. The tape measure includes a fluid-based retraction speed controller. The speed controller may be formed from a rotor/stator arrangement. The rotor is coupled to the reel and the stator is coupled to the housing opposing the rotor. The rotor converts some rotational energy from tape reel into movement of a fluid (e.g., movement of air, movement of oil, etc. through friction) which acts to slow or limit the retraction/rotational speed of the reel as the retraction spring expands driving the reel during tape blade retraction."

3. Plain-language overview of the disclosure

A standard spring‑return tape measure (housing, reel, coiled blade with hook, spiral spring) is fitted with a fluid‑based (air or oil) brake on the side of the reel. A vaned rotor spins with the reel; a matching vaned stator is fixed to the inside of the housing facing it. Rotor vanes (with planar, parallel major faces, and semicircular concave surfaces between adjacent vanes) drive air along the toroidal gap and into the fixed stator vanes, where kinetic energy is dissipated by friction. Because drag scales with rotational speed, braking is nearly absent during the slow initial acceleration phase and increases automatically at high speed — exactly when blade "whip" and hook‑slap damage occur. Being non‑contact, the arrangement is also described as low‑wear.

4. Independent claims — plain-language overview

The patent has 22 claims, with three independent claims (1, 13, 21). All three share the same preamble elements: a housing; a tape reel rotatably mounted in the housing defining a rotation axis and having a radially outward facing surface; an elongate tape blade wound on that surface; and a spring‑based retraction system whose spring stores energy on unwind and releases it to rewind the blade.

Claim 1 — "rotor vane" claim (broadest structural concept).
The distinguishing element is a rotor comprising a vane rigidly coupled to the tape reel, such that the rotor spins with the reel during retraction. Notably, claim 1 does not require a stator, a second vane, a fluid, or any explicit braking function — it is essentially a tape measure whose reel carries a rotor vane. Dependent claims add: an axle defining the rotation axis (2); vane geometry with first/second parallel major surfaces facing counter‑clockwise and clockwise (3); a non‑rotationally fixed stator facing the rotor (4) with a radially extending wall (5); vane radial length of 50–150% of blade width (6) and 0.5–2 in (7); a second vane plus an outward‑facing concave surface between vanes (8); blade max extension 10–50 ft (9); a hook assembly (10); rotor positioned axially between reel and housing inner surface (11); and a cylindrical coaxial outer wall of the rotor (12).

Claim 13 — "fluid speed control device" claim.
Adds a speed control device coupled to the tape reel that converts rotational energy of the reel into movement of a fluid inside the housing, plus a dimensional limitation: the speed control device's outer diameter is within 5% of the tape reel's outer diameter. Dependent claims add: braking proportional to reel speed (14); rotor + opposing non‑rotating stator (15); plural radial rotor vanes (16) with the counter‑clockwise/clockwise parallel major faces (17); plural radial stator vanes (18) with the same face geometry (19); and hook assembly, 10–50 ft blade, and air and/or oil fluid (20).

Claim 21 — "rotor/stator speed control device" claim.
The narrowest‑framed of the three independent claims and the closest to the commercial embodiment: a speed control device comprising (a) a rotor rigidly coupled to the reel so it spins with the reel during both extension and retraction, and (b) a stator non‑rotationally fixed in the housing and opposing the rotor. Claim 22 depends on it and adds the full plural‑vane geometry for both rotor and stator, with first/second parallel major surfaces facing counter‑clockwise and clockwise.

Practical effect: claims 21/22 (and to a degree 15–19) track the illustrated FIG. 2–5 structure; claim 1 is the most exposed to prior art because it requires only a reel‑mounted rotor vane and no stator or fluid interaction.

5. Prior art cited of note

Among the 32–37 cited references, the most structurally relevant are: US 3,889,897 (Stanley Works, self‑regulating speed control); US 2008/0263886 A1 and the Komelon family (US 8,215,027; 8,429,830; EP 2,562,510) for self‑regulating speed control; US 2004/0035971 A1 (deceleration device of a tape rule); US 6086007 (viscously damped cord retract); US 4,046,434 (hydromatic brake); and US 2012/0055740 A1 (Holmes Solutions braking mechanisms). The examiner also cited US 2,904,282 (Lufkin) and JP 2013‑137280 A. None of these appears to disclose the specific rotor‑on‑reel / fixed‑stator air‑drag arrangement as claimed.

6. Litigation / PTAB / CAFC check (searches run 2026‑04‑26)

• No Federal Circuit appeal, district court docket entry, ITC investigation, or PTAB proceeding naming US 11,022,417 was located.
• The Milwaukee tape‑measure litigation activity that does show up on the dockets concerns different patents: Milwaukee Electric Tool Corp. v. Klein Tools, Inc., No. 1:25‑cv‑04689 (N.D. Ill., filed 04/29/2025) asserting US 11,656,067 ("Tape Measure with Increased Standout"); PGR2020‑00056, Apex Tool Group LLC v. Milwaukee Electric Tool Corp, on US 10,422,617; and IPR2026‑00233, Klein Tools Inc v. Milwaukee Electric Tool Corp, on US 11,656,067 (filed 2026‑01‑26).
• A 2026 ITC proceeding involving Klein and Milwaukee concerns helmet patents and "glow fish tape" patents — again unrelated to the '417 patent.

Uncertainty caveat: the absence of hits in a general web search is not affirmative proof that no proceeding exists, since I could not query PACER, the CAFC docket, or the new USPTO PTAB APIs directly. For a definitive clearance check on US 11,022,417, a direct PACER/PTAB/PatentCenter query should be run.

7. Summary of confidence

• Bibliographic data, abstract, claim text, and prior‑art citations: high confidence (taken from the authoritative full patent text).
• Family/prosecution and maintenance‑fee details: high confidence (consistent across Google Patents, Justia, and foreign family records).
• Litigation status: moderate confidence — no proceedings found, but verified only through public web search rather than direct docket access.

I'll search for litigation involving US patent 11022417 across patent litigation sources.

Initial searches returned no results. Let me try additional sources and search formulations.

The search results mention other Milwaukee tape-measure patents (e.g., US 10,422,617 and US 11,656,067) but not 11,022,417 specifically. Let me run more targeted searches.

Litigation Search: U.S. Patent No. 11,022,417

Bottom line

No litigation (district court, Federal Circuit, ITC, or PTAB) specifically asserting or challenging U.S. Patent No. 11,022,417 appears in any of the sources I searched. I was unable to identify a single case — plaintiff, defendant, jurisdiction, case number, or filing date — in which the '417 patent is the patent-in-suit.

I want to be explicit about the limits of this answer: I could not fully execute the search strategy you specified. My queries against the Unified Patents litigation portal, Docket Alarm, and general web search returned no case list for this patent number (Unified Patents' "caselist" is a PTAB-focused tool and returned only unrelated Unified petitions; Docket Alarm search queries for this patent returned nothing). One of my final scheduled searches hit a step limit and did not return. So this is a "not found" result, not a verified negative — a confirmatory check against PACER/Docket Navigator/Unified Patents portal by a human would be advisable before relying on it.

Search results — what I did find (all NOT the '417 patent)

Every litigation/proceeding my searches surfaced involving Milwaukee tape-measure technology concerns different patent numbers. I list them here so you can see they were checked and excluded, not conflated with the '417 patent:

Critical caution: US 10,422,617 and US 11,656,067 are distinct patent numbers from US 11,022,417. Do not treat any of the above as litigation over the '417 patent. The subject matter ("tape blade profile increasing tape standout") also differs from the '417 patent's subject matter ("Tape Measure with Fluid-Based Retraction Speed Controller," a rotor/stator fluid-damping retraction speed control). Per your instruction to interpret numbers literally and not auto-correct, I have kept these separate.

About the '417 patent itself (from the authoritative patent text)

• Patent No.: US 11,022,417 B2; Title: "Tape measure with fluid-based retraction speed controller"
• Application No.: US 15/928,954; filed 2018-03-22; granted/publication date 2021-06-01
• Inventor: Scott Earl McKinster; Assignee: Milwaukee Electric Tool Corporation
• Priority: 2017-03-24 (U.S. Provisional 62/476,354)
• Continuation of PCT/US2018/023602 (published as WO2018175612A1); child continuation US 17/244,345 (US 11,680,784 B2)
• Legal status: Active, adjusted expiration 2039-11-20
• The patent's citation record shows it is cited by later Milwaukee applications (e.g., US 2021/0247170 A1 and US 11,680,784 B2), and it cites prior art such as US 3,889,897 (Stanley Works "self-regulating speed control mechanism"), US 4,906,775/4,907,756 winding brakes, and US 8,215,027/8,429,830 (Komelon self-regulating speed control) — but citing a patent is not litigation involving it.

What would change this answer

If a case exists, it would most likely be a later-filed Milwaukee assertion (given the '417 patent issued in 2021 and its continuation issued in 2023), or a declaratory-judgment/PTAB challenge by a competitor. None appeared in my searches. I recommend confirming via:

• PACER (search civil cases by patent number) — https://pacer.uscourts.gov
• Unified Patents litigation portal — https://portal.unifiedpatents.com/litigation/caselist (filter by the patent number)
• Docket Alarm / Docket Navigator by patent number

Caveat on confidence: I have low-to-moderate confidence in this "no litigation" conclusion because my tool access to the litigation databases you named was incomplete. I am not aware of any case involving US 11,022,417, and I could not retrieve one; I would not represent to a court or client that none exists without the confirmatory database check above.

PTAB / AIA Trial Landscape — US Patent 11,022,417

Patent: US 11,022,417 B2 — "Tape measure with fluid-based retraction speed controller"
Patent Owner / current assignee: Milwaukee Electric Tool Corporation
Inventor: Scott Earl McKinster
App. No.: 15/928,954 · Filed: 2018-03-22 · Priority: 2017-03-24 · Granted: 2021-06-01
Continuation in family: US 11,680,784 B2 (app. 17/244,345, filed 2021-04-29)

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Proceedings overview

Total AIA trial proceedings on the '417 patent: 0. Per the USPTO Open Data Portal block provided in this prompt, there are no IPR, PGR, or CBM proceedings on file for US 11,022,417 — no institution denials, no settlements, no final written decisions, no certificates of cancellation. I ran independent web searches for any PTAB filing naming the '417 patent (or its application number 15/928,954) and found none; I also found no Federal Circuit appeal touching it.

Bottom-line defensive posture: This is an untested, un-narrowed patent. All 22 claims sit exactly as issued — nothing has been canceled, nothing has been confirmed by the Board, and no IPR estoppel has been created. Unlike a patent that "survived two IPRs and is hardened," the '417 has never been through an adversarial validity proceeding at the Office. That cuts both ways for a defendant: there is no PTAB roadmap to borrow and no petitioner estoppel to leverage, but also no claims you must treat as Board-blessed. An IPR is an open, unimpeded option for the first challenger.

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Per-proceeding detail

None to report. No AIA trial proceeding number attributable to US 11,022,417 exists in the structured ODP data or in public search. I will not manufacture a proceeding number or outcome.

Adjacent activity that is NOT a proceeding on this patent (flagging so it isn't mistaken for one):

• PGR2025-00048 — Milwaukee Electric Tool Corporation v. Klein Tools, Inc. — This is Milwaukee as petitioner, and the challenged patent is US 12,187,573 (a modular-storage/related-family patent), not the '417. The Petitioner's Sur-Reply (dated 2025-09-05) confirms the subject patent is the '573 patent. (See Docket Alarm, PGR2025-00048.)
• Additional 2025 IPR/PGR filings by Milwaukee against Klein (e.g., the filings referenced in the '209-patent sur-reply) likewise concern other Milwaukee patents in other families (helmet and fish-tape technologies), not the '417.
• Milwaukee Elec. Tool Corp. v. Klein Tools, Inc., No. 1:25-cv-04689 (N.D. Ill., filed 2025-04-29) asserts US 11,656,067 ("Tape measure with tape blade profile increasing tape standout") — a different patent family (priority 2017-08-24) than the '417. Klein's accused products are tape measures (models 9225, 9125AL, 9125), but the asserted claims are blade-profile claims, not the '417's fluid-speed-controller claims.
• The 2015–2017 Milwaukee IPRs (IPR2015-00595/596/597; IPR2015-01164/1165/1166; IPR2016-00343/344/345) concerned Milwaukee's lithium-ion battery-pack patents ('290/'173/'510/etc.). They are unrelated to the '417 and predate its 2017 priority date.

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Strategic summary

Claim status of the '417. Every claim is UNTESTED and SUSSUSTAINED — there are no CANCELED claims and no SUSTAINED (Board-confirmed) claims. Independent claims 1, 13, and 21 and all dependent claims (2–12, 14–20, 22) stand as granted. The claim set covers a fluid-based (air/oil) rotor-stator retraction speed controller: independent claim 1 is the rotor-vane apparatus claim; claim 13 adds the "outer diameter of the speed control device within 5% of an outer diameter of the tape reel" limitation; claim 21 is the rotor-plus-stator claim. Any defendant must assume the full issued claim set is live.

Estoppel landscape. Because no IPR or PGR has been instituted or decided, § 315(e)(2) / § 325(e)(2) estoppel has not attached against anyone. No petitioner is barred from raising any prior-art ground. For a new defendant, the entire universe of patents and printed publications (§ 102/§ 103) remains available in an IPR, subject only to the ordinary § 311(b) limits and the § 315(b) one-year bar running from service of an infringement complaint. There is no "reasonably could have raised" trap to worry about, and — conversely — nothing in the file that pre-empts your own art.

Pattern signals. Milwaukee is an assertive, not a passive, patent owner: it is currently the petitioner in multiple 2025 IPRs/PGRs against Klein and the plaintiff in the April 2025 tape-measure suit. As a patent owner, however, it has not yet had the '417 tested at the Board, and there is no defensive aggregator (e.g., Unified Patents) in the chain on this patent. The '417 also has a live continuation (US 11,680,784) in the same family, so any validity position you develop should account for claim scope that may issue in the '784 and future continuations.

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Recommended next steps

• No PTAB activity exists on this patent — state that plainly to whoever is evaluating the demand letter. The absence is a signal: the '417 is a young, narrowly-asserted patent (issued 2021-06-01, and I found no public evidence it has been separately asserted), so it simply has not yet attracted a challenger. It is not "hardened."
• If you intend to challenge validity, an IPR is fully available and unencumbered. Consider the fluid-speed-controller art cited on the face of the patent as a starting point — e.g., US 3,889,897 (Stanley Works, "self-regulating speed control mechanism"), US 4,907,756 (Sam Outillage, winding brake), and the Komelon self-regulating speed-control family (US 8,215,027 / 8,429,830) — none of which has been adjudicated against the '417.
• Timeline discipline: no statutory clock has started on this patent from any AIA proceeding (there are none). Your only clock is § 315(b) — one year from service of a complaint asserting the '417. If you are served, calendar the IPR deadline immediately; if the patent has not been asserted against you, monitor the N.D. Ill. Milwaukee v. Klein tape-measure case, which may signal whether Milwaukee begins asserting the broader tape-measure portfolio, including the '417.
• If you are a defendant and the patent owner cites this patent as "validated": it has not been validated at the Board — there is no FWD, no certificate, nothing to quote. Any assertion to the contrary can be corrected with the record above.

Verification sources: Google Patents US11022417B2 (family, continuity, and cited art), the ODP "PTAB proceedings on file" block (zero proceedings), Docket Alarm entries for PGR2025-00048 and Milwaukee v. Klein (1:25-cv-04689, US 11,656,067). No PTAB E2E or CourtListener opinion is cited because no proceeding or appeal concerning the '417 patent was located.

Caveat: I found no AIA proceeding on this patent with high confidence; the absence of any proceeding number is a finding, not an omission. If a recently filed, not-yet-indexed petition exists, it would not appear in the ODP ingest and I was unable to surface one via search.

I'll verify the assignment record against the primary sources before writing.

Let me attempt to pull the recorded correspondent/attorney details directly.

Assignment & Ownership Analysis — US 11,022,417 B2

"Tape measure with fluid-based retraction speed controller"
Appl. No. 15/928,954 · filed 2018-03-22 · granted 2021-06-01 · priority 2017-03-24 (Prov. 62/476,354)

Source note / limitation up front: The Google Patents legal-events record supplied for this patent contains exactly one assignment event and gives the reel/frame. It does not expose the correspondent of record field. I could not retrieve the Assignment Center detail page (assignmentcenter.uspto.gov is a session-driven JS application that is not indexed by search engines), and targeted web searches for the reel number returned nothing. I therefore do not state a correspondent name below rather than infer one — see signal #3 for why that matters and what I could not confirm.

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Inventors

Unusual-pattern check: None of the tell-tale patterns appear. There is no multi-inventor team that dispersed, and the sole inventor did not assign away from the original employer. The continuation US 11,680,784 B2 was filed 2021-04-29 and issued 2023-06-20 — more than four years after the 2017 priority filing — still naming Milwaukee Electric Tool Corporation as assignee. An inventor-departure fire-sale would normally show the family bleeding off to a third party by that point; it did not. No departure/fire-sale indicator present.

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Original assignee

Milwaukee Electric Tool Corporation — 13135 West Lisbon Road, Brookfield, Wisconsin 53005. A Delaware corporation; publicly identified as a subsidiary within the Techtronic Industries Company Limited group (Rule 7.1 corporate disclosure statements in Milwaukee Electric Tool Corp. v. Apex Tool Group, LLC, D. Del. 1:20-cv-00913, and in Milwaukee Electric Tool Corp. v. Schedule A Defendants, S.D.N.Y. 1:26-cv-04061, both identify Esstar Industries, Inc. / Techtronic Industries Company Limited as the ultimate parent).

• Primary line of business: professional-grade power tools, hand tools, accessories and measuring tools — including retractable tape measures. Milwaukee is one of the largest US trade-channel hand-tool brands.
• Product embodying the claims: Yes. Applicant's own specification describes the fluid-based rotor/stator retraction damper as the commercial design (rotor 52 on the reel, stator 54 on housing half 16 — FIGS. 2–5). The '417 and its sibling tape-measure patents cover Milwaukee's "Wide Blade" / Stud tape measure line; a PTAB exhibit in PGR2020-00056 (Patent Owner Exhibit 2003) is a webpage documenting release of Milwaukee's Canadian Wide Blade tape measures — direct evidence of commercial embodiment in the same product family.
• Current status: Operating. Currently the assignee of record. Maintenance fee for the 4th year paid 2024-12-02 (large entity), and the patent is shown Active with an adjusted expiration of 2039-11-20. The parent, Techtronic Industries, is a listed, going-concern company. No bankruptcy, no dissolution, no acquisition of the patent owner.

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Assignment timeline

One recorded assignment exists. There are no post-issuance recordings for the '417 — the original assignee still owns it.

• 2018-04-24 (executed) / recorded 2018-05-04 — Reel 045721/0939
  • Conveyance: Assignment (Assignment of Assignors' Interest) — per the Google Patents legal-events entry ASSIGNMENT OF ASSIGNOR'S INTEREST;ASSIGNOR:MCKINSTER, SCOTT EARL;REEL/FRAME:045721/0939; Effective date: 20180424
  • Assignor: Scott Earl McKinster (sole inventor)
  • Assignee: Milwaukee Electric Tool Corporation
  • Correspondent: Not retrievable from the available sources. The Google Patents legal-event record does not expose the correspondent field, and I could not load the Assignment Center record for this reel/frame. I decline to name an attorney here. (For context only — not a finding about this assignment — Milwaukee's separate trademark filings name Michael Best & Friedrich LLP, Laura M. Konkel, Madison WI, and Reinhart (Milwaukee Tool) as correspondents of record. Those are TSDR trademark records and must not be conflated with the patent assignment correspondent on reel 045721/0939.)
  • Context: Routine employer-employee rights transfer — the standard "hereby assign" instrument executed at/near filing to perfect Milwaukee's title in its employee's invention. Not a sale, not a reorg, not a securitization.

Family/chain note (for completeness, not a separate recorded assignment on the '417): the same disclosure, priority chain and assignee carry through the continuation US 11,680,784 B2 (US 17/244,345, filed 2021-04-29) and the Chinese family members CN 110446904 B and CN 114485309 B, all shown with Milwaukee Electric Tool Corporation as owner. There is no second US hop, no IP-holding subsidiary, no recording to any entity with an "IP / Holdings / Ventures / Licensing" suffix.

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Timeline diagram

timeline
    title Ownership of US 11022417
    2017 : Provisional filed by McKinster
    2018 : PCT and US applications filed
         : Inventor assigns rights to Milwaukee
         : Application published Sep 27
    2021 : Patent issued Jun 1

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NPE / troll-pattern signals

1. Shell-entity transfer — not present.
The only recorded conveyance is reel 045721/0939, inventor → Milwaukee Electric Tool Corporation, an operating manufacturer at a Brookfield, WI corporate address. No entity with an "IP / Holdings / Ventures / Licensing" suffix appears anywhere in the chain, and there is no single-purpose Delaware or Texas LLC. No registered-agent-service address appears.

2. Known asserter in the chain — not present.
Neither the assignor (McKinster) nor the assignee (Milwaukee Electric Tool Corporation) matches any public NPE list (Acacia, Marathon, Intellectual Ventures, IPNav, Wi-LAN, Mosaid/Conversant, Vringo, Pendrell, Innovatio, MPHJ, Lumen View, Round Rock, Document Generation Corp, Spangenberg entities). The assignee is a product manufacturer and is, if anything, on the defensive side of NPE activity — it appears as patent owner and IPR/PGR respondent in PTAB proceedings (e.g. PGR2020-00056, Apex Tool Group LLC v. Milwaukee Electric Tool Corp, filed 2020-04-10, terminated 2020-10-13 as settled).

3. Repeat correspondent across the chain — unclear / insufficient data.
There is only one recorded assignment, so recurrence cannot be established — and that is dispositive: a single appearance would not be a finding anyway under the stated test. Compounding this, the correspondent field for reel 045721/0939 is not available in any source I could reach. I am flagging this as a genuine data gap rather than asserting a correspondent. If you can open the Assignment Center record for reel 045721/0939, the correspondent there is the one field worth capturing — but on a one-hop inventor→manufacturer assignment, its diagnostic value is very low.

4. Cascading transfers — not present.
Zero consecutive assignments, let alone chained LLCs within 24 months. The entire recorded history is one hop, executed 2018-04-24 and recorded on 2018-05-04 — a 10-day gap consistent with same-period prosecution filing, not with assertion staging.

5. Pre-litigation transfer — not present.
The only assignment predates issuance by more than three years. Caveat on scope: my searches did not surface an infringement action naming US 11,022,417 specifically. Milwaukee's public tape-measure assertions located were over sibling patents — D. Del. 1:20-cv-00913, Milwaukee Electric Tool Corp. v. Apex Tool Group, LLC / Apex Tool Group SAS, filed 2020-07-06, asserting US 10,697,747 and US 10,712,142 against Crescent Lufkin Shockforce tape measures (voluntarily dismissed with prejudice 2020-09-23); and a separate action against Klein Tools reported by ToolGuyd. Because no suit on the '417 was found, there is no assignment within six months of a first suit to evaluate.

6. Bankruptcy fire-sale — not present.
Milwaukee Electric Tool Corporation / Techtronic Industries have not filed Chapter 7 or 11. No assignment-in-bankruptcy, no 363 sale, no IP auction. The 4th-year maintenance fee was paid 2024-12-02 by the original owner.

7. Privateering — not present.
Privateering requires an operating company to transfer to an NPE that asserts on its behalf. Here the operating company kept the patent and asserts it itself, in its own name, against direct trade competitors (Apex Tool Group / Crescent Lufkin, Klein Tools). That is the opposite of privateering — no conduit entity, no SEC or Patent Progress / EFF coverage of a Milwaukee-funded assertion vehicle.

8. Defensive aggregator — not present.
The chain does not terminate at RPX, AST, LOT Network, Unified Patents, or OIN. The patent remains with the manufacturer; it has not been neutralized.

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Verdict

Operating-company assertion.

Justification: the complete recorded chain for US 11,022,417 is a single assignment — reel 045721/0939, executed 2018-04-24, recorded 2018-05-04 — moving title from sole inventor Scott Earl McKinster to Milwaukee Electric Tool Corporation, a Delaware corporation in the Techtronic Industries group that designs and sells tape measures embodying the claimed fluid-based rotor/stator retraction damper (FIGS. 2–5; PTAB PGR2020-00056 Patent Owner Ex. 2003 documents commercial Wide Blade tape measures). No post-issuance assignment, IP-holding subsidiary, NPE assignee, or defensive-aggregator transfer appears anywhere in the record, and the patent remains Active with the 4th-year maintenance fee paid by the original owner on 2024-12-02.

Honest caveat on verdict strength: strictly as to the '417 itself, no assertion lawsuit was located — the confirmed Milwaukee enforcement activity (D. Del. 1:20-cv-00913 against Apex Tool Group over US 10,697,747 / 10,712,142; the Klein Tools action) is over sibling tape-measure patents from the same portfolio. If you require assertion of this specific patent number, the more conservative label would be "Insufficient data — only the original assignment;" either way, no NPE directionality is supported by any record in this chain.

Verify at: https://assignment.uspto.gov/patent/index.html (search patent number 11022417) and https://assignmentcenter.uspto.gov/ — confirm the sole entry is reel 045721/0939 and capture the correspondent field, which I could not retrieve.

I'll research the prior-art citations for US 11,022,417, focusing on the structurally most relevant references. Let me run targeted searches.

Let me research the remaining structurally relevant citations, including the fluid/viscous-damping references.

Prior-Art Analysis — US 11,022,417 B2

Builds on the previously generated sections. The bibliographic data, abstract, claim overview, and the short "prior art cited of note" summary were produced earlier and are not repeated here. This section goes claim-element-by-claim-element through each of the 37 references listed in the "Patent Citations (37)" table of the authoritative patent text, adds the non-patent citation, and assigns a § 102 exposure verdict per independent claim.

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1. Method, scope, and one contradiction flagged

Rule applied. § 102 anticipation requires that a single reference disclose every element of a claim, arranged as in the claim. A reference that discloses the tape-measure preamble (housing + reel + blade + spiral-spring retraction) but a different speed-control mechanism does not anticipate an independent claim of the '417 patent; it is § 103 material. I therefore separate "potential § 102 anticipation" from "§ 103 combination material" for each reference.

Statutory posture. The '417 patent's effective filing date is 2017-03-24. Every cited reference published 1934–2013, i.e., all are § 102(a)(1)/(a)(2) prior art with respect to the '417 patent. The only question is what they disclose, not whether they qualify.

Contradiction with a previously generated section (flagged per instructions). The earlier "Litigation summary" referred to winding-brake art as "US 4,906,775/4,907,756." The authoritative patent text lists a single reference, US 4,907,756 A (Sam Outillage S.A., "Winding brake for spring-return tape measure," priority 1988-04-01, published 1990-03-13). The "4,906,775" figure appears nowhere in the '417 citation record. Treat the earlier attribution as an error; this section uses US 4,907,756 A literally.

Access limitation. I retrieved full text for the structurally key references (US 3,889,897; US 2008/0263886; the Komelon family; US 2004/0035971; US 6,086,007; US 4,446,884). For the remaining tape-measure references I relied on the patent's own titles/assignees plus the family records surfaced in search; where I did not read full text, I say so and hedge the § 102 verdict. I did not reach live USPTO full-text search within this session, so some bibliographic tie-breaks carry lower confidence than the claim analysis itself.

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2. Tier 1 — Fluid / viscous / air-damping references (most probative to the '417 core)

These are the only citations that disclose fluid-based (air or liquid) energy dissipation, the feature that distinguishes the '417 patent.

2.1 US 6,086,007 A — Ericsson Inc., "Viscously damped cord retract"

• Filed 1998-06-01; published 2000-07-11.
• Description (full text retrieved). A retractable spool (105) for a flexible member — expressly including "tape measure" as one example flexible member — with a vaned air-damper member 110 disposed concentrically inside the spool hub. Vanes (190) "define a plurality of air filled rotatable chambers." Rotation of the damper "gives rise to a rotational frictional force that creates an opposing rotational torque that resists the rotational velocity of the spool 105. The magnitude of the opposing rotational torque is proportional to the rotational velocity of the spool 105 and the volume of air displaced by the air-damper member." (Source: https://patents.google.com/patent/US6086007 ; PDF https://patentimages.storage.googleapis.com/26/03/66/8df03f4c57206a/US6086007.pdf)
• § 102 assessment. This is the single most dangerous reference in the citation set because it teaches the inventive function of the '417 patent — velocity-proportional air damping via a vaned member. However, it does not anticipate any independent claim:
  • Claim 1 requires "a rotor comprising a vane rigidly coupled to the tape reel such that the rotor spins along with the tape reel during retraction." In US 6,086,007 the air-damper is driven through an internal gear assembly (hub gear 165 / idler gears 175 / pinion gear 205) at a different rotational velocity than the spool — i.e., it is neither rigidly coupled to the reel nor a tape-measure reel. Missing element → no anticipation of claim 1.
  • Claim 13 requires the speed control device to be "coupled to the tape reel" within a tape measure having a blade wound on the reel and a spring retraction system, and to be within 5 % of the reel's outer diameter. US 6,086,007's device is not a tape measure reel and the concentric damper sits inside the hub, not at the reel's outer diameter. No anticipation.
  • Claim 21 requires a "stator non-rotationally fixed within the housing and opposing the rotor." US 6,086,007 has no stator facing a rotor (its damper works inside the rotating hub). No anticipation.
• Net: § 103 gem. Combined with any spring-return tape-measure reference in this list, it would render claim 13 (and the fluid concept of claims 1/21) prima facie obvious. It is the reference the patent owner most needs to distinguish.

2.2 US 4,446,884 A — Rader, Jr., "Take-up reel with controlled rewind velocity"

• Filed 1981-06-08; published 1984-05-08.
• Description (full text retrieved). A fluid shear damper for a spring-rewound reel: a damper chamber 58 containing hydraulic fluid 62, a stator disc 60 rigidly attached to a stator hub 54 fixed to the shaft, and a rotor/damper housing (plates 50, 52) that rotates with the take-up reel. "The rotation of the damper housing relative to the fixed stator gives rise to viscous friction forces which cause a conversion of the mechanical energy into shear or unavailable thermal energy." (PDF: https://patentimages.storage.googleapis.com/31/88/a3/c2047e568a41f7/US4446884.pdf)
• § 102 assessment. This reference teaches rotor/stator fluid shear with a non-rotating stator — arguably closer to claim 21's structure than US 6,086,007 — but:
  • It is a hose/air-hose take-up reel, not a tape measure; no tape blade with graduated markings, no hook assembly. Claims 1, 13, 21 preambles missing.
  • The "rotor" is a smooth disc/damper housing, not a vaned rotor opposing a vaned stator. Claim 21 recites "a rotor … a stator … opposing the rotor"; claim 22 adds plural vanes. No anticipation; § 103 material — particularly for the liquid (oil) embodiment the '417 specification expressly contemplates ("a liquid fluid, such as oil, may be located within the rotor/stator arrangement").

2.3 US 4,043,434 A — Parmac, Inc., "Mechanically adjustable dual pocket hydromatic brake"

• Filed 1974-08-29; published 1977-08-23.
• Description (title/assignee basis; full text not retrieved this session). A hydromatic (fluid) brake with adjustable dual pockets — a fluid-damping/retarding device, but in a general mechanical-brake context, not a tape measure.
• § 102 assessment. Discloses fluid braking but none of the tape-measure structural elements of claims 1/13/21. No § 102 anticipation of any claim. Listed as § 103 background showing fluid braking is a known retarding expedient.

2.4 US 2004/0035971 A1 — Shin-Lin Li, "Deceleration device of a tape rule"

• Filed 2002-07-08; published 2004-02-26.
• Description (full text retrieved). A tape rule with a speed-reduction gear wheel meshing a transmission gear coaxially fitted to the reel, retarding reel rotation; engagement is released by a pusher plate. Notably, claim 4 recites that the deceleration unit may be "operated with oil pressure or pneumatic pressure, or by other mechanical means." (Sources: https://insight.rpxcorp.com/patent/US20040035971A1 ; https://patexia.com/us/publication/20040035971)
• § 102 assessment. Discloses the tape-measure preamble (housing, reel, tape, spring retrievability) plus a deceleration device — but the device is a gear train, not a reel-mounted rotor vane driving fluid, and there is no stator. The oil/pneumatic option appears only in a claim of Li and is not structurally enabled as a rotor/stator air drag arrangement. No § 102 anticipation of claims 1, 13, 21. High-value § 103 reference: a tape-measure skilled artisan combining Li with US 6,086,007 or US 4,446,884 reaches the '417 concept.

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3. Tier 2 — Tape-measure self-regulating speed control (the "obviousness backbone")

All of these disclose the full '417 preamble (housing, reel, graduated blade, spiral-spring retraction) plus a speed control whose braking effect increases with reel speed — i.e., they disclose every functional advantage the '417 specification touts, but by contact/centrifugal friction, not fluid drag. None anticipates an independent claim; collectively they are the primary § 103 base.

3.1 US 3,889,897 A — The Stanley Works, "Coilable tape measuring device having a self-regulating speed control mechanism" (examiner-cited)

• Filed 1973-09-26; published 1975-06-17.
• Description (full text retrieved). Coilable rule with reel 40 mounted on spindle 36; a weighted mass pivoted on the reel side member bears against an arcuate brake drum surface on the casing "in proportion to the centrifugal force applied to the reel by the power drive spring … thereby self-regulat[ing] the recoil speed." Expressly aimed at preventing excessive recoil speed and lateral flutter/wear. (Sources: https://patents.google.com/patent/US3889897/en ; PDF https://patentimages.storage.googleapis.com/4c/fa/9f/eb4479f099ef84/US3889897.pdf)
• § 102 assessment. Discloses: housing; reel with axis; blade; spring retraction; and a reel-coupled member producing speed-proportional braking. It does not disclose a fluid energy conversion, a vane rigidly coupled to the reel (the mass is pivoted), or a stator. No anticipation of claims 1, 13, or 21. This is the classic § 103 primary reference for the "self-regulating retraction speed" preamble and the "braking increases with speed" dependent claim 14.

3.2 US 2008/0263886 A1 — Kang (Dong Hun), "Tape measure with a self-regulating speed control mechanism" (examiner-cited)

• Filed 2007-04-24; published 2008-10-30.
• Description (full text retrieved). Casing 10, bobbin 20, blade 30, first elastic member 40 (coil spring). A rotary brake part 50 pivoted on the bobbin sidewall swings outward under centrifugal force against a stationary brake part 11 protruding from the casing (ring-shaped, centered on the bobbin rotation center); a second elastic member 60 biases the brake away from contact at low speed. Speed-dependent contact braking. (Sources: https://patents.google.com/patent/US20080263886A1/en ; PDF https://patentimages.storage.googleapis.com/74/ef/78/19882db7302bde/US20080263886A1.pdf)
• § 102 assessment. Same profile as 3.1: full preamble + speed-proportional contact braking. No fluid, no vaned rotor, no stator. No anticipation of claims 1, 13, 21. § 103 reference; also relevant to claim 14.

3.3 Komelon family — US 8,215,027 B2; US 8,429,830 B2; EP 2,562,510 A2; WO 2011/132948 A2 (and JP 2013-525,784 A family member)

• Priority 2010-04-23 (KR 10-2010-0037804); publications 2011-10-27 (WO), 2012-07-10 (US 8,215,027), 2013-02-27 (EP 2,562,510 A2), 2013-04-30 (US 8,429,830).
• Description (full text retrieved). Tape measure whose bobbin carries movable mounting plates; a rubber roller on each plate swings outward under centrifugal force and alternately contacts a support ring on the casing and rubber "acceleration prevention members" fixed on the ring's inner surface, reducing bobbin speed; contact braking disabled at low speed by a cantilever second elastic member. (Sources: https://patents.google.com/patent/[US8215027B2](/patent/US8215027B2)/en ; EP PDF https://patentimages.storage.googleapis.com/6e/80/d7/3c06838ebee363/EP2562510A2.pdf ; WO PDF https://patentimages.storage.googleapis.com/3c/21/b9/05f9d01df787d6/WO2011132948A2.pdf)
• § 102 assessment. Full preamble + speed-proportional contact braking; also teaches the "low impact at low speed, greater braking at high speed" behavior the '417 touts. Still contact friction against a stationary ring, not fluid drag, and no vaned rotor. No anticipation of claims 1, 13, 21. These four are the closest tape-measure § 103 references and are the references an examiner would most likely pair with a fluid-damping reference (Tier 1) to reject claim 13/21.

3.4 US 2012/0055740 A1 — Holmes Solutions Limited, "Braking mechanisms" (examiner-cited)

• Filed 2009-03-10; published 2012-03-08.
• Description (title/family basis; full text not retrieved). Centrifugal/braking mechanism art (the family is cited broadly in retraction-speed-control contexts).
• § 102 assessment. Given the "braking mechanisms" scope and no indicator of a tape-measure rotor/stator fluid arrangement, no § 102 anticipation of claims 1, 13, 21; treat as § 103/§ 102(a)(1) background. Confidence: moderate-to-low — I did not read full text; recommend verification if this reference is relied on.

3.5 US 4,907,756 A — Sam Outillage S.A., "Winding brake for spring-return tape measure"

• Filed/priority 1988-04-01; published 1990-03-13.
• § 102 assessment. A friction winding brake in a spring-return tape measure — full preamble, contact braking, no fluid/rotor/stator. No anticipation of claims 1, 13, 21; § 103 background. (See flagged contradiction in § 1 above re the earlier "4,906,775" mention.)

3.6 US 5,829,154 A — Lin Ping Lin, "Tape measure with flexible braking strips" (examiner-cited)

• Filed 1997-08-07; published 1998-11-03.
• Description. Flexible braking strips with pressing blocks that frictionally contact the reel side-plate edges to control rewinding.
• § 102 assessment. User-actuated friction braking on a reel — full preamble, but no speed-proportional fluid control, no rotor vane, no stator. No anticipation of claims 1, 13, 21.

3.7 JP 2013-137280 A — Hara Doki KK, "Control method for winding speed of measuring tape of tape measure"

• Filed/priority 2011-12-28; published 2013-07-11.
• Description (title basis). A method for controlling measuring-tape winding speed in a tape measure.
• § 102 assessment. Method-directed; on its face no rotor/stator fluid structure. No § 102 anticipation of the apparatus claims 1, 13, or 21. Relevant, if at all, as § 102(a)(1) art for method-type claims (the '417 has none) or § 103. Confidence: low on substance (Japanese-language reference; full text not retrieved).

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4. Tier 3 — Tape-measure retraction / cartridge / brake references (preamble art only)

These disclose the conventional tape-measure architecture of claims 1/13/21's preamble but nothing of the fluid speed control. None anticipates any independent claim; they are at most cumulative § 103 background.

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5. Tier 4 — Other braking / retraction-art references

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6. Non-patent citation

• International Search Report and Written Opinion for PCT/US2018/023602, dated 2018-07-11, 15 pages. This is the search report for the '417 patent's own PCT parent (published as WO 2018/175612 A1). It is not itself prior art; it documents the examiner's/ISA's search and the art deemed relevant to the same invention, and is useful for confirming which of the above references drove the original examination.

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7. Synthesis — claim-by-claim § 102 exposure

Bottom line: none of the 37 cited references appears to be a clean § 102 anticipator of any independent claim of the '417 patent. Every independent claim requires a reel-mounted, rigidly coupled rotor vane (claim 1) or a fluid-converting speed control (claim 13) or a rotor + opposing fixed stator (claim 21) in a spring-return tape measure. The cited art splits cleanly into two camps that must be combined under § 103:

Primary § 103 combinations a challenger would run:

1. US 3,889,897 (or US 2008/0263886 / Komelon family) as primary — discloses spring-return tape measure with self-regulating, speed-proportional retraction braking — in view of US 6,086,007 (vaned air damper giving velocity-proportional damping) and/or US 4,446,884 (rotor/stator fluid shear) to supply the fluid rotor/stator element; further in view of US 4,043,434 (hydromatic brake) for fluid braking. This combination maps onto claim 13 and, with the stator of US 4,446,884, onto claim 21.
2. US 2004/0035971 (tape-rule deceleration device, claim 4 reciting oil-pressure/pneumatic operation) as a secondary reference reinforcing that fluid/pneumatic retraction deceleration in tape rules was known.

Best non-cited risk to note: US 6,116,933 / US 6,115,933 (Li, "Tape measure with decelerating mechanism") and US 6,086,007 appear in the same art space; a full invalidity search should confirm whether any un-cited reference discloses a vaned rotor ringed directly on a tape-measure reel with a facing fixed vaned stator — that is the specific combination that would be needed for a § 102 (rather than § 103) challenge to claim 21/22.

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8. Confidence

• Claim-element mapping and § 102/§ 103 characterization: high confidence — grounded in the authoritative claim text and the full specification's own statements about what is and is not disclosed.
• Descriptions and dates for US 3,889,897; US 2008/0263886; US 8,215,027/8,429,830/EP 2,562,510/WO 2011/132948; US 2004/0035971; US 6,086,007; US 4,446,884: high confidence (full text retrieved this session).
• References assessed from title/assignee/family only (US 4,043,434; US 2012/0055740; US 2012/0087820; JP 2013-137280; and the Tier 3/4 tape-measure patents): low-to-moderate confidence on substance. Their "no anticipation" verdicts rest on the absence of any indication of a rotor/stator fluid arrangement plus the absence of the claim-13 diameter limitation, not on a full read. If any of these is to be relied upon in a validity opinion, retrieve and read its full text first.
• The flagged contradiction (US 4,907,756 A vs. the previously stated "4,906,775/4,907,756") should be corrected in the earlier section; the authoritative citation list contains only US 4,907,756 A.

I'll ground my reading of the key references before constructing the § 103 analysis.

Obviousness Analysis — U.S. Patent No. 11,022,417 (35 U.S.C. § 103)

Analyst note on scope. This section builds on the Patent summary (bibliography, abstract, claim overview) and Litigation summary already generated above. I do not repeat them. It relies on the Prior Art section of the Google Patents page supplied as the authoritative text ("Citations (32)" / "Patent Citations (37)," plus "Family Cites Families (12)"), supplemented by my retrieval of the underlying documents where they were reachable. Where I could not retrieve a reference's substance, I say so and limit my reasoning to what the citation record itself establishes.

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0. Two correction flags before substantive analysis

1. Cross-section discrepancy. The previously generated Patent summary, §5, refers to prior art "US 4,906,775/4,907,756." The authoritative citation list contains only US 4,907,756 A (Sam Outillage S.A., "Winding brake for spring-return tape measure," 1988‑04‑01 / 1990‑03‑13). The string "4,906,775" does not appear anywhere in the citation record. I treat 4,907,756 as the correct reference and flag "4,906,775" as a transcription artifact.
2. Post-dated references in the "Family Cites Families" list must not be used as prior art. That list mixes true prior art (e.g., CN 2362096 Y, 2000; US 8,898,922 B2, 2011) with later Milwaukee family filings whose priorities post‑date the '417 priority date of 2017‑03‑24 — specifically EP 3,997,414 B1 (priority 2019‑07‑12) and CN 113939709 B (priority 2019‑06‑14). Under § 102(a)(2)/§ 103, neither can be prior art against the '417 patent. They are evidence of the assignee's later product direction, nothing more.

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1. Framework and level of ordinary skill

PHOSITA. A bachelor's degree in mechanical engineering (or equivalent experience) plus roughly 2–4 years designing spring‑return retraction mechanisms, tape measures, or small consumer power tools; familiarity with centrifugal braking, viscous/air damping, and hydrodynamic rotor–stator (retarder) brakes. The '417 solution is entirely mechanical; no specialized fluid‑dynamics or electronics skill is required.

Governing law. Graham v. John Deere, 383 U.S. 1 (1966); KSR Int'l Co. v. Teleflex Inc., 550 U.S. 398 (2007); In re Keller, 642 F.2d 413 (CCPA 1981) (combining references as a whole); In re Aller, 220 F.2d 454 (CCPA 1955) and In re Woodruff, 919 F.2d 1575 (Fed. Cir. 1990) (claiming a broad range overlapping a disclosed range, absent criticality, is obvious); MPEP § 2143 (rationales).

Claim construction notes that drive the analysis.

• "rotor comprising a vane rigidly coupled to the tape reel" (claim 1) — "rigidly coupled" is expressly defined in the '417 specification: "coupled in a manner such that the components move together in a fixed positional relationship when acted upon by a force." This is fixed, not centrifugally deployable.
• "speed control device … converts rotational energy of the reel to movement of a fluid within the housing" (claim 13) — the fluid may be air or oil (claim 20), and no sealing, chamber, or pressure limitation is recited.
• "outer diameter of the speed control device is within 5% of an outer diameter of the tape reel" (claim 13) — a bare dimensional range; the specification supplies no criticality, describing 5% only as "about the same" to describe a fit relationship (rotor 52 vs. reel 20).
• Claims 1–20 vs. 21–22: claims 21–22 are the commercial-embodiment claims (rotor + fixed opposing stator, bidirectional rotation).

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2. The citation record, organized into four teaching groups

Key evidentiary point. The '417 specification admits the entire Group D architecture and, more importantly, admits the problem: "the typical tape measure spiral spring delivers excess energy … which in turn translates into undesirably high retraction speeds and whip, particularly toward the end of retraction." That admission converts the problem to be solved into prior art and narrows the § 103 inquiry to the damping mechanism alone.

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3. Grounds of rejection

Ground 1 — Claims 1–12 over Komelon/Stanley in view of Ericsson '007 (and Parmac '434 for the vane geometry)

Claim 1 mapping. The preamble (housing, rotatably mounted reel with outward‑facing surface, blade wound on it, spring retraction system) is met by US 8,215,027 / US 2008/0263886 (Komelon: casing 100, bobbin 110, blade 120 with graduations wound on the bobbin, first elastic member/coil plate spring returning the blade) and by US 3,889,897 (Stanley: casing 10, reel 40, coiled blade 18 with hook 42, power drive spring 20). The sole additional element — a rotor comprising a vane that spins with the reel — is met by US 6,086,007, whose air‑damper member 110 comprises "a plurality of vanes 190" that are rotated when the spool rotates and that "give[s] rise to a rotational frictional force that creates an opposing rotational torque that resists the rotational velocity of the spool." Critically, '007 lists "tape measures" as one of the flexible members 125 it is designed for — an express, not inferred, field‑of‑use overlap.

Dependent claims.

• 2 (axle defining the axis) — Stanley's center post 28 / stationary spindle 36; Komelon's bobbin rotation axis.
• 3, 17, 19, 22 (vane with a first major surface facing counter‑clockwise and a second facing clockwise, parallel to each other) — in substance met by US 4,043,434, which discloses rotor and stator vanes that are "planar vanes extending radially across said pockets and tilted in said rotor in the direction of rotation of said rotor, and tilted in the opposite direction in the stator"; a planar tilted radial vane necessarily presents two oppositely facing major surfaces.
• 4–5 (non‑rotating stator facing the rotor with a radially extending wall) — Komelon's support ring 101 protruding from the casing toward the bobbin sidewall with acceleration prevention members 170 on its inner surface; and '897's arcuate brake drum surface on the casing wall confronting the reel. For the "radially extending wall," Parmac '434's stator vanes are radial.
• 6–7 (vane radial length 50–150% of blade width; 0.5–2 in.) — bare ranges with no disclosed criticality; scaling a damper vane to the blade/reel envelope is a predictable design choice (In re Aller / In re Woodruff).
• 8 (second vane + concave surface facing outward between vanes) — Parmac's rotor having plural webs defining plural pockets across a half‑circle cross‑section annular cavity is structurally the same toroidal‑channel‑with‑vanes concept.
• 9–10 (10–50 ft blade; hook assembly) — conventional (Stanley's hook 42; blade-length ranges are commercial choices).
• 11 (rotor axially adjacent the reel, between reel and housing inner surface) — Komelon's movable mounting plates sit on the bobbin sidewall, i.e., between the reel and the casing wall; '897's weighted mass is pivotably mounted between the side member and the confronting casing wall.
• 12 (coaxial cylindrical outer wall of the rotor) — inherent in any coaxial reel‑side damper disc (Komelon's support ring/bobbin coaxial geometry; Rader '884's coaxial annular damper).

Ground 2 — Claims 13–20 over Komelon '027/'886 (or Stanley '897) in view of Rader '884 or Ericsson '007

Claim 13 mapping. Komelon/Stanley supply every preamble element plus a speed control coupled to the reel. The converting element — "converts rotational energy of the reel to movement of a fluid within the housing" — is squarely met by:

• US 4,446,884 (Rader): a take‑up reel driven by a wind‑up spring motor 24 with a viscous damper assembly 30 in which the damper housing (rotor hub) rotates with the take‑up reel while a stator disc 60 is rigidly fixed to the support shaft; rotation "gives rise to viscous friction forces which cause a conversion of the mechanical energy into shear or unavailable thermal energy," expressly proportional to rewind velocity ("controlled rewind velocity"). This is, structurally, the claimed invention minus the tape blade and a hand‑held housing — both supplied by Group D/Komelon.
• US 6,086,007 (air variant): damping torque "proportional to the rotational velocity of the spool," air chambers, and an express tape‑measure application. Because claim 20 recites "at least one of air and oil," '007's air embodiment alone satisfies the fluid limitation; Rader's hydraulic fluid satisfies the oil alternative.

The 5% outer‑diameter limitation. The specification gives this range no criticality — it merely records that rotor 52's diameter is "about the same (e.g., within 5% of each other) as the outer diameter of reel 20." Rader's damper assembly is an annular plate assembly mounted coaxially on the same shaft as, and side‑by‑side with, the take‑up reel, sized to the reel envelope to fit the support structure. Matching a coaxial side‑mounted damper's diameter to the reel it is packaged against is the definition of a predictable packaging design choice under KSR.

Dependents 14–19 — velocity‑proportionality (14) is met by both Rader and Ericsson; rotor+fixed stator (15) by Rader (damper housing vs. stator disc 60); plural radial rotor vanes (16) and stator vanes (18) by '007 ('plurality of vanes 190') and '434 (plural planar radial vanes in both rotor and stator); the CCW/CW major‑face geometry (17, 19) by '434.

Ground 3 — Claims 21–22 over Komelon/Stanley + Ericsson '007 + Parmac '434 (with Rader '884 as the primary fluid‑damper reference)

Claim 21 mapping. Rotor rigidly coupled to the reel and spinning during both extension and retraction + non‑rotating stator opposing the rotor:

• US 4,043,434 teaches exactly a facing rotor/stator pair with radially extending vanes dissipating rotational energy into a fluid, keyed to a rotating shaft (rigid) with the stator fixed to the housing ("The stator 22 is supported by a planar flange 23 which is clamped … between the parts 12 and 14 of the housing").
• US 4,446,884 teaches the same pairing on a spring‑rewound reel, in a two‑directional, bidirectional viscous damper (it damps during both payout and rewind).
• Komelon '027/'886 / Stanley '897 teach that in a tape measure the speed‑control member goes on the bobbin/reel sidewall and reacts against a casing‑fixed ring or brake drum — i.e., the claimed axial placement and reel‑coupling.
• US 6,086,007 teaches that the fluid element can be a vaned rotor on the reel of a retractable device, including a tape measure, with velocity‑proportional damping.

Claim 22 (plural rotor and stator vanes, each with CCW/CW facing parallel major surfaces) is met by the combined teaching of '434 alone as to vane geometry, applied to the Komelon/Stanley tape‑measure reel.

Ground 4 (alternative / cumulative) — "obvious to try" with a finite, identified solution set

Where the art of Group A had identified the problem and the design space ("self‑regulating speed control mechanism" appears in the titles of US 3,889,897, US 2008/0263886, US 8,215,027, US 8,429,830, EP 2,562,510, WO 2011/132948), and Group B had identified the finite alternative of non‑contact fluid damping (air: '007; liquid: '884, '434; hose‑reel rewind speed control: WO 2011/072337 and its US continuations), selecting fluid damping for a tape measure reel is an "obvious to try" variation with a reasonable expectation of success (KSR; MPEP § 2144.05).

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4. Articulated motivation to combine (the part that must be explicit)

1. Same field, same problem, same solution class. Komelon's specification itself cites and discusses US 3,889,897 and US 2008/0263886 as earlier solutions to the identical problem ("to prevent the rotational speed of the bobbin from increasing," avoid injury/damage to the tape measure). References within the same field addressing the same problem are combinable (Keller).
2. The art was dissatisfied with contact‑type (friction) speed control — a direct incentive to go non‑contact/fluid. Komelon's own experimental table records that its friction approach produced "a very loud noise," a "phenomenon of the bobbin stopping during the retraction of the blade" because friction was "excessively high," and that several variants "cannot provide the speed reduction effect." The '417 patent's stated advantages — speed‑proportional braking, no‑contact energy transfer, "less wear and longer life span" — are the predictable remedies for exactly those reported failure modes. Nothing about the remedy is unpredictable: the ordinary artisan knows that fluid shear/drag torque scales with relative velocity and involves no wearing contact surfaces.
3. Known technique improving a known device. Fluid‑damper retrofits to spring‑returned reels were a known technique ('884 damper on a spring‑rewound take‑up reel; '007 air damper on a spring‑biased cord/spool retractor expressly covering tape measures), and applying it to the admitted conventional spring‑return tape measure is "the use of a known technique to improve a similar device in the same way" (KSR).
4. Design incentive / packaging. Mounting the damper disc on the side face of the reel, coaxial with the rotation axis and within the reel's diameter, is dictated by the packaging of a hand‑held tape measure housing — the very placement Komelon uses for its movable mounting plates (bobbin sidewall, inside the support ring) and Stanley uses for its pivotable weighted mass. The 5% OD relationship and the vane‑length ranges (claims 6–7) are the kind of "design choice … according to the particular application" that KSR treats as obvious.
5. Reasonable expectation of success, plus bridging the "rigid coupling" gap. '007's air damper is driven directly by the spool through a gear train and rotates whenever the spool rotates (both directions); '884's damper housing is fixed to and rotates with the take‑up reel in both directions; '434's rotor is keyed to its shaft. Any of these supplies a rigidly coupled, bidirectionally spinning vaned rotor, satisfying claim 21's requirement that the rotor spin during both extension and retraction.

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5. Claim‑by‑claim vulnerability summary

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6. Where the patent retains defensible ground

A rigorous challenger must confront these genuine gaps; I flag them rather than paper over them.

1. "Rigidly coupled" excludes the centrifugal‑mass references on their own. Stanley '897's weighted mass is "pivotably mounted" and bears against the brake drum "in proportion to the centrifugal force"; Komelon '027's movable mounting plate moves radially by centrifugal force; Komelon '886's rotary brake part pivots about a shaft. None is rigidly coupled within the '417's express definition. Any § 103 theory that relies on Group A alone therefore fails on claim 1's "rigidly coupled" limitation — the challenger must add a fluid‑damper reference ('007, '884, or '434) to supply it.
2. Claim 13's numeric OD limitation is not literally disclosed — only approximately inherent in Rader's coaxial packaging. Expect the patentee to argue no reference "teaches" the 5% figure. The counter is Aller/Woodruff plus the specification's own lack of criticality.
3. Ericsson '007 arguably disparages liquid damping ("a need … without relying on a fluid damper assembly"; "if the liquid seal is compromised, the retracting forces … may not effectively damp"). This is a weak teaching‑away argument (it attacks seal reliability of liquid dampers, while its own solution is an air damper — still a fluid), and it does not reach claim 20's "air and/or oil" alternative because '007 supplies air. I would not rely on it for the '417's air embodiment.
4. Secondary considerations. Milwaukee's commercial tape measures may enjoy market success, but the fluid damper is internal and not a consumer‑facing feature; establishing nexus between any commercial success and the claimed rotor/stator would be difficult. I found no litigation, PTAB proceeding, license, or industry‑praise evidence tied to the '417 patent in the earlier Litigation summary, so there is presently no secondary‑considerations record to rebut the prima facie case.
5. Claim 21's bidirectionality is a real limitation and is met only by '884 (bidirectional viscous damper on a spring‑rewound reel) or '007 (spool‑driven air damper) — not by the Group A references, whose brakes engage only above a centrifugal threshold and thus do not "spin along with the tape reel during extension and retraction" as a fixed structure. This makes the '884/'007 combination load‑bearing for claims 21–22; if either reference were disqualified (e.g., as non‑analogous art, which I consider unlikely given both are spring‑returned reeling devices and '007 names tape measures), claims 21–22 would be materially harder to invalidate.

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7. Confidence statement

• High confidence in the content of, and my characterization of, US 3,889,897, US 6,086,007, US 8,215,027 / US 8,429,830 / US 2008/0263886 / WO 2011/132948, US 4,043,434 (and Parmac siblings), and US 4,446,884 — full texts or claim texts were retrieved and quoted (Google Patents: https://patents.google.com/patent/US3889897 ; https://patents.google.com/patent/US6086007 ; https://patents.google.com/patent/[US8215027B2](/patent/US8215027B2)/en ; https://patents.justia.com/patent/[4043434](/patent/4043434) ; https://patentimages.storage.googleapis.com/31/88/a3/c2047e568a41f7/US4446884.pdf).
• Moderate confidence for the Spray Nozzle hose‑reel family (WO 2011/072337 A1, US 2012/0298784 A1, US 2014/0117136 A2), US 4,907,756, US 4,687,155, US 5,829,154, US 2004/0035971 A1, US 2005/0191107 A1, US 8,056,849 B2, US 2012/0087820 A1, JP 2013‑137280 A, and CN 2,362,096 Y — I reasoned from the citation record and titles, not the documents.
• Explicitly not verified: the actual figures/photographs in US 4,446,884 for the damper's outer diameter relative to the take‑up reel, and the degree of structural identity between Parmac's half‑circle annular pocket and the '417's semicircular surface 66/80. Both should be confirmed against the drawings before filing any paper that asserts them.
• Not a validity opinion. This is an analytical assessment of § 103 exposure based on the patent's own citation record. A formal invalidity search would need to canvass non‑cited art (e.g., rotary dashpot/hydraulic retarder art, angled‑vane pneumatic dampers for retractors) and the prosecution history of US 15/928,954 for any examiner statements on the rotor/stator concept.