US 10996077

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

Let me refine with more targeted searches.

Summary of US Patent 10,996,077 B2

Search caveat up front: My tooling is a general web search, not a live USPTO PatentCenter / PACER / CAFC docket query. I could confirm the patent's bibliographic record (via Google Patents and cross-citations in other patents), but I found no evidence of any CAFC appeal, IPR, or district-court litigation involving US 10,996,077 in 2026 (or any year). I cannot affirmatively certify a negative from a docket; treat "no litigation found" as a search result, not a guarantee.

Bibliographic data

Cited prior art of record: US 4,697,144 A (Verify Electronics, 1987), JP 2000-180209 A, US 6,329,813 B1, JP 2001-255108 A, US 2002/0011838 A1, and JP 2008-032546 A.

Abstract

An electromagnetic induction type encoder includes a detection head and a scale. The detection head has a transmitter coil that generates magnetic flux. The scale has connection coils arrayed in a measurement axis direction, electromagnetically coupled with the transmitter coil's flux, generating flux fluctuating at a predetermined spatial period along the measurement axis. The detection head has a receiver coil with multiple coils arrayed in the measurement axis direction on a face of the detection head, coupled with the flux from the connection coils to detect its phase. The current direction of one coil is opposite to that of the adjacent coil.

Plain-language overview of the claims

Claim 1 (the only independent claim). An electromagnetic induction (inductive/coupled-coil) encoder with two rectangular parts — a detection head and a scale — that face each other and slide relative to one another along a measurement axis. The head carries:

• a transmitter coil that generates magnetic flux;
• a receiver coil made of multiple coils arranged along the measurement axis on one face of the head, which pick up (are coupled to) flux from the scale's connection coils and detect its phase.

The scale carries multiple connection coils arrayed along the measurement axis that are coupled to the transmitter flux and re-radiate flux fluctuating at a set spatial period.

The core limitation: adjacent coils in the receiver coil carry current in opposite directions (the "twisted pair"/figure-8 effect used to cancel external disturbance), and the receiver coil is built on the head's substrate with these specific structural features:

• the receiver coils are open-loop coils;
• first coils and second coils are alternately arrayed;
• the first coils have their terminal on one side face of the substrate that is parallel to the measurement axis, and the second coils have their terminal on the other (opposite) side face;
• the first coils are connected to one another in order through their terminal on the one side, and the second coils are connected in order through their terminal on the other side.

Practically, this is the point of novelty over the comparative multilayer design described in the specification: by routing the first-coil terminals along one long edge and the second-coil terminals along the opposite long edge, the opposite current directions are achieved on a single wiring layer and without any crossing/intersection — eliminating the need for a two-layer (bonded printed-substrate) receiver coil and the layer-to-layer alignment error that could create an unintended coil shape and degrade measurement accuracy.

Claim 2 (dependent on claim 1). Requires two or more receiver coils and two or more transmitter coils; each receiver coil has a different phase from the others, and each transmitter coil surrounds a respective one of the receiver coils. (Supports two-phase/multi-phase position detection, including the stacked-layer variant described in the specification.)

Claim 3 (dependent on claim 1). Requires that the first coils are connected without crossing and the second coils are connected without crossing — i.e., the express single-layer, intersection-free wiring limitation that is the stated technical advantage of the disclosure.

Notes and uncertainties

• There is only one independent claim, so "each independent claim" reduces to claim 1; claims 2 and 3 are dependent and both narrow claim 1.
• The patent is no longer in force in the US (maintenance-fee lapse effective 2025-05-04), which is relevant context if you were looking for live enforcement or CAFC activity — an expired, fee-lapsed patent with no identified litigation is consistent with the absence of any 2026 appeal.
• I did not independently verify the JP/CN/DE family members' current status, nor did I retrieve the USPTO file wrapper (office actions, applicant remarks). The 2021-03-02 "response to non-final office action" entry suggests at least one substantive rejection was traversed before allowance — if you need the prosecution history for estoppel or claim-construction purposes, pull the file wrapper directly from PatentCenter.
• I found no CAFC docket entry, IPR, or district-court case naming US 10,996,077; if you need a definitive docket check, query PACER/CourtListener and the CAFC docket by patent number directly, since my search coverage is not exhaustive.

Authoritative source used: https://patents.google.com/patent/US10996077/en (fetched 2026-09-24), which is consistent with the full text supplied in the prompt.

I'll search for litigation involving US patent 10996077.

The initial searches returned no relevant litigation. Let me search more specifically using litigation databases.

Litigation Search Results for U.S. Patent No. 10,996,077

No litigation involving U.S. Patent No. 10,996,077 was found.

I searched for the specific patent number across litigation-oriented sources (Unified Patents portal references, PACER/court-docket aggregators, CourtListener, and general web/court-filing searches). None of the results identified any district court action, ITC investigation, PTAB proceeding (IPR/PGR), or Federal Circuit appeal (CAFC) in which U.S. Patent No. 10,996,077 was asserted, challenged, or otherwise at issue.

What I checked and what came back

Important caveats

• Distinguish similar numbers. Some results referenced nearby but different identifiers (e.g., U.S. Pat. No. 10,996,037; the Scantech v. INSIZE case involving U.S. Pat. No. 10,914,576). Per the strict rule, I am not treating these as the patent in question.
• Tool limitations. I was unable to complete a full interactive query of the Unified Patents litigation portal (portal.unifiedpatents.com/litigation/caselist) or run live PACER/CAFC docket lookups within this session. My conclusion is based on the search results actually returned. A definitive negative would ideally be confirmed by directly querying:
  • Unified Patents Portal – litigation and PTAB caselists
  • PACER (all district courts) for the patent number
  • CAFC docket search
  • USPTO PTAB API/PTAB Center for any post-grant proceedings

Patent status context (from the authoritative patent text)

• Title: "Electromagnetic induction type encoder"; assignee Mitutoyo Corp.; inventor Hiroto Kubozono.
• Priority date: 2018-10-04; filed 2019-10-02; granted 2021-05-04.
• Status: Expired – Fee Related. Maintenance fees were not paid; the patent expired/lapsed effective 2025-05-04 (recorded 2025-06-09).
• No assertions of this patent appear in the record, and its early lapse is consistent with (though not proof of) a lack of enforcement activity.

Bottom line: Based on the searches performed, there is no known litigation involving U.S. Patent No. 10,996,077. If a definitive, database-confirmed negative is required, I recommend running direct queries against the Unified Patents Portal, PACER, and the PTAB/CAFC dockets, and I can describe exactly which queries to run.

PTAB / AIA Trial Analysis — US 10,996,077 B2 ("Electromagnetic induction type encoder," Mitutoyo Corp.)

Data source note: The structured "PTAB proceedings on file" block supplied in this prompt — the canonical list from the USPTO Open Data Portal — returns zero AIA trial proceedings for US 10,996,077. Three independent web queries (patent number alone; patent number + Mitutoyo + IPR; PTAB/Unified Patents/docket aggregators) surfaced no IPR, PGR, or CBM petition, no PTAB Final Written Decision, and no Federal Circuit appeal touching this patent. I found no proceeding number to report, and I will not invent one.

Proceedings overview

Total AIA trial proceedings on file for US 10,996,077: 0. Breakdown: 0 active, 0 with claims invalidated, 0 with claims sustained, 0 settled, 0 institution denials. The defensive posture this gives a defendant is neutral-to-adverse: the patent has never been tested at the PTAB, so all three issued claims stand unadjudicated with the full statutory presumption of validity — you get no free ride from an earlier petitioner's work, and any § 315(e)(2) estoppel that might have narrowed the art space simply does not exist here.

Proceedings

None to report. There is no {PROCEEDING_NUMBER} to populate. For the avoidance of doubt, the following are the categories I checked and found empty:

• Inter Partes Review (IPR) — none. No petition, no institution decision, no FWD.
• Post-Grant Review (PGR) — none. Note the patent's filing date (2019-10-02, claiming priority to JP 2018-189210 filed 2018-10-04) puts it squarely in PGR-eligible territory post-AIA as a first-inventor-to-file case, and the 9-month PGR window closed on or about 2020-05-04 without a filing.
• Covered Business Method (CBM) — none, and in any event CBM review is unavailable for this subject matter (a measuring-instrument/encoder patent is not a "financial product or service" patent under AIA § 18(d)(1)); the § 18 CBM program has also sunset.
• Reexamination (ex parte or inter partes) — none surfaced.
• Federal Circuit appeals — none. With no FWD, there is nothing appealable to the CAFC under 35 U.S.C. §§ 141(c)/319.

Strategic summary

Claim status: claims 1, 2, and 3 are all UNTESTED. US 10,996,077 issued with exactly three claims (claim 1 independent; claims 2 and 3 dependent). Because no AIA trial ever reached a Final Written Decision, no claim has been canceled, confirmed, or amended by the PTAB, and no certificate under 35 U.S.C. § 318(b) has issued. For a defendant, this cuts both ways: you cannot point to a dead claim to defuse a demand letter, and the patent owner cannot point to a PTAB affirmance to harden claim 1. The claim set is exactly as it left the examiner.

Substantively, claim 1 is a fairly narrow apparatus claim and that narrowness is worth pricing into your invalidity budget. It requires not just the generic electromagnetic-induction-encoder architecture (detection head + scale + transmitter coil + arrayed connection coils + receiver coil of arrayed coils with alternating current direction), but a specific structural package: the receiver coil on a single substrate face, the coils being open loop coils, an alternating first-coil/second-coil array, first coils terminating on one side face parallel to the measurement axis and second coils terminating on the other side face, with the first coils connected in order through their terminal and the second coils connected in order through theirs. Dependent claim 3 adds connected without crossing — the express point of the disclosure, which is designed to eliminate the multilayer/through-wiring construction that the specification criticizes in the comparative embodiment (FIGS. 2A–2B, 3A–3B). Dependent claim 2 covers the two-or-more-receiver-coil / per-coil-surrounding-transmitter-coil configuration with differing phases.

Estoppel landscape: there is none, and that is the headline for you. Section 315(e)(2) estoppel attaches only to a petitioner that obtains a Final Written Decision. Since no IPR/PGR was ever instituted or decided against this patent, no petitioner, real party in interest, or privy is estopped from anything, and no prior-art ground is foreclosed to you. Practically, that means you face no "could have raised" trap: you may assemble an IPR petition on any § 102/§ 103 ground, including art that a hypothetical earlier petitioner would have used. The corollary risk is that you are also the first mover — there is no institution decision anywhere to reverse-engineer claim constructions from, and no PTAB precedent on how the Board would read "open loop coil," "circulated" wiring, or the side-face terminal-placement limitations. Claim construction risk on this patent is entirely unquantified.

Pattern signals: absent, not merely negative. There is no serial petitioner, no defensive aggregator (Unified Patents or similar) in the chain, and no PTAB appeal history for the patent owner on this asset. The citation record shows Mitutoyo actively cites this patent's own family members and later Mitutoyo filings (e.g., JP7294902B2, JP7431032B2, the US 11,167,414 / US 11,181,395 / US 11,169,008 transmitter-receiver-configuration family) as related art, which suggests a healthy internal portfolio rather than a contested one. The most plausible explanation for the total absence of PTAB activity is simply that this patent has not been asserted in a way that made an IPR economically rational — not that it is unassailable.

Recommended next steps

If you are a defendant being asserted against today: do not expect a shortcut. There is no FWD to cite, no canceled claim to quote, and no estoppel to leverage. Two things follow:

1. Budget a full invalidity case rather than an IPR-cleanup case. Because nothing has been litigated, you would be filing a first-of-kind petition. Under General Plastic / Fintiv-line discretionary considerations, a parallel district court action with an early trial date could still cost you institution — plan the timing accordingly, and consider whether the district court or the PTAB is the better first venue.
2. Attack the claim-1 structural limitations, not the concept. The broad "electromagnetic induction type encoder" idea is decades old (the specification itself cites JP 2000-180209, JP 2001-255108, and JP 2008-032546; the prosecution citation list includes US 4,697,144 to Verify Electronics). The narrowing features — single-face receiver coil, open-loop coil geometry, the specific first/second coil terminal routing to opposite side faces, and claim 3's no-crossing connection — are where a § 103 combination should be built. Any prior art showing an inductive position transducer with alternately-wound open-loop receiver coils traced to opposite substrate edges, with the coils daisy-chained without crossover, is your target.

If you are looking for PTAB activity to monitor: the correct answer is that there is none, and the absence is itself a signal worth briefing to your client in exactly those terms. Well-asserted measuring-instrument patents do attract IPRs; this one has not, over roughly seven years since issuance. Before you rely on that, re-run the check against USPTO PTAB E2E / the PTAB "Patent Trial and Appeal Board" search at https://ptacts.uspto.gov and the CAFC docket, since the ODP ingest lags and a recently filed petition may not yet be indexed. Note also that the patent's US maintenance fee lapsed: per the Google Patents legal events, the patent expired for failure to pay maintenance fees effective 2025-05-04 (lapse recorded 2025-06-09). If that status is accurate and not merely a data artifact, the patent is no longer enforceable, which would moot infringement exposure entirely — verify this against the USPTO Patent Center fee history before relying on it in a demand-letter response, because I cannot confirm it from the structured data provided, and the "Expired - Fee Related" label in the fetched page is a machine annotation, not an official USPTO determination.

I'll verify the assignment record and check for any post-issuance transfers.

Let me verify the assignment record and check for any additional ownership events.

Let me try the USPTO assignment API and check for any post-issuance records.

I've hit my search-step limit, so I'll report what the authoritative record supports and be explicit about the one field I could not retrieve.

Ownership Analysis — US 10,996,077 B2

Scope note: The USPTO Assignment Center (https://assignmentcenter.uspto.gov/) and its legacy interface (https://assignment.uspto.gov/patent/index.html) are interactive JavaScript applications behind a search form; my tooling here is a general web search, not a live Assignment Center / ODP API client. I could not execute an interactive reel/frame query. However, the authoritative full text of the patent supplied in this analysis contains a machine-readable Legal Events table sourced from the same USPTO assignment data that the Assignment Center serves. Everything below is grounded in that table. I could not retrieve the correspondent of record — it is not exposed in the Legal Events table, and my queries did not surface it. Treat that field as unresolved (flagged inline below) rather than as "none."

Inventors

Pattern observations:

• Single-inventor patent — no inventor-team fragmentation, no evidence of the "all inventors depart within 12 months of filing" fire-sale precursor. Kubozono was a Mitutoyo employee assigning to his employer, the classic corporate invention-assignment posture.
• I found no evidence that Kubozono left Mitutoyo, and no published record tying him to any later NPE or licensing entity. I cannot affirmatively confirm his continued employment (my search coverage is not a personnel database); I state only that no contrary evidence surfaced.
• The assignment's effective date (2019-09-05) precedes the US filing (2019-10-02) by less than a month, which is normal practice — the inventor assigned before filing, not in response to any transfer event.

Original assignee

Mitutoyo Corporation — Japanese precision-metrology manufacturer, headquartered at 20-1, Sakado 1-chome, Takatsu-ku, Kawasaki-shi, Kanagawa 213-8533, Japan. Named as both original and current assignee.

• Primary line of business: dimensional metrology — micrometers, calipers, coordinate measuring machines, optical/laser measurement systems, and the digital readout scales and encoders that this patent covers. Encoders are a core, shipping Mitutoyo product line, not a paper asset.
• Product embodying the claims: Yes, in the practical sense. The patent's own classification (G01D 5/204–5/2073) and the specification's direct framing of an electromagnetic induction type encoder for a detection head/scale pair place it squarely in Mitutoyo's shipping encoder-scales product family. I have not independently verified that a specific commercial SKU reads on claims 1–3 — that would require a product teardown or datasheet-to-claim chart, which I did not perform.
• Current status: Operating. Mitutoyo remains an active filer: external portfolio analytics surfaced in my search (plainpatent.com, drawing on USPTO PatentsView) put Mitutoyo at ~820 US grants across 2015–2025, rank #549 of tracked assignees, primary CPC subclass G01B. That is the profile of a live operating manufacturer, not a wound-down or bankrupt entity.
• No acquisition, merger, or name change involving Mitutoyo Corporation appears in the chain for this patent.

Assignment timeline

Exactly one assignment is recorded. There are no post-issuance assignments, no security interests, no releases, and no corrections in the record.

• 2019-09-05 (executed) / recorded 2019-10-02 — Reel 050601 / Frame 0841
  • Conveyance: Assignment (recorded as "ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS)")
  • Assignor: KUBOZONO, HIROTO (individual)
  • Assignee: MITUTOYO CORPORATION (Japan)
  • Correspondent: ⚠️ Not retrieved. Not exposed in the Legal Events record I have, and I could not reach the Assignment Center's detail view to read the recording attorney/agent. I therefore cannot assess the "repeat correspondent" signal. Do not read this as "no correspondent" — every recorded assignment has one; I simply could not read it.
  • Context: Initial corporate invention assignment. Employee-inventor assigns pre-filing rights to his employer; no third party, no consideration structure, no reorg. USPTO event code AS, REEL/FRAME 050601/0841, effective 2019-09-05.

No further assignment records exist for this patent. Per the task instruction, that is itself the finding: the original assignee (Mitutoyo Corporation) remained the sole owner of record from 2019 through the patent's lapse. There is no post-issuance transfer, and consequently no NPE acquisition, no aggregation, and no privateering chain to analyze.

Corroborating status events (not assignments, but relevant to ownership value):

• 2021-04-14 — patent granted (STCF "PATENTED CASE").
• 2024-12-23 — maintenance-fee reminder mailed.
• 2025-06-09 — lapse recorded for failure to pay maintenance fees (STCH, 37 CFR 1.362); effective date 2025-05-04.

The lapse is notable for an ownership analyst: a company that had sold or securitized this patent (particularly to an NPE that intended to assert it) would have had a strong economic incentive to keep the maintenance fee paid. Mitutoyo let it lapse — consistent with a large operating portfolio doing routine pruning, and inconsistent with any assertion program built on this asset.

Timeline diagram

timeline
    title Ownership of US 10996077
    2018 : JP priority application filed
    2019 : Inventor assigns rights to Mitutoyo
         : US application filed
    2020 : Pre-grant publication
    2021 : Patent granted
    2025 : Lapsed for unpaid maintenance fee
         : Patent expires

(A single-link chain makes this diagram deliberately sparse — there is one ownership event to render.)

NPE / troll-pattern signals

Verdict

Insufficient data — under the task's own definition, "only the original assignment." The complete ownership record for US 10,996,077 consists of a single internal invention assignment: inventor Kubozono → Mitutoyo Corporation, executed 2019-09-05, recorded 2019-10-02 at Reel 050601 / Frame 0841. There is no post-issuance transfer, no security interest, and no assertion entity anywhere in the chain, so there is no NPE pattern to score — the signals are absent by absence of links, not by affirmative exculpatory evidence.

Substantively, the strongest available characterization is non-asserting operating-company ownership: the patent stayed with its original operating-company assignee (a shipping metrology manufacturer) for its entire life and was allowed to lapse for non-payment of maintenance fees effective 2025-05-04 (recorded 2025-06-09). An owner positioning an asset for assertion does not let it expire.

The one material gap: I could not retrieve the correspondent of record on Reel 050601/0841 — the field most diagnostic of repeat-player NPE counsel. Here it is unlikely to change the verdict (a single-link chain held by a product company has no NPE counsel pattern to reveal), but if you need it closed, query the Assignment Center detail view for reel 050601 frame 0841 directly.

Verify at: https://assignmentcenter.uspto.gov/ → "Patent Assignment Search" → search by patent 10,996,077, or by reel/frame 050601/0841. Legacy mirror: https://assignment.uspto.gov/patent/index.html.

I'll verify the patent record and each cited reference against authoritative sources.

Now let me verify the remaining cited references.

Let me verify the remaining three Japanese-origin references.

Prior-Art Analysis — US 10,996,077 B2

Scoping and caveats (read first)

• Identifier interpreted literally: US 10,996,077 B2, "Electromagnetic induction type encoder," US App. No. 16/590,641, filed 2019-10-02, granted 2021-05-04, priority JP 2018-189210 (2018-10-04), assignee Mitutoyo Corporation, inventor Hiroto Kubozono. I did not substitute any visually similar number.
• Source limitation: My results below come from Google Patents, FreePatentsOnline, and patent-PDF mirrors — not a live USPTO PatentCenter/PAIR "References Cited" query. I could not complete a direct USPTO database pull within this session (the final two tool calls were cut off by a step limit). The six references below match the citation list on the face of US 10,996,077 (the "Patent Citations (6)" and "Citations (4)" tables in the authoritative text), so the set is reliable even though I did not render it from USPTO's own server.
• Critical date: The AIA applies (filed 2019). The effective prior-art cut-off is the JP priority date, 2018-10-04. Every reference below predates that by 10+ years, so each qualifies as prior art under 35 U.S.C. § 102(a)(1)/(a)(2).
• Important expectation-setting: These are the references the examiner considered of record, and the application was allowed after a 2021-03-02 response to a non-final office action. On its face, that argues these references did not anticipate the allowed claims. My § 102 analysis below therefore distinguishes "discloses the anti-phase receiver-coil feature" from "discloses every element of a claim." I flag where a reference is closer to § 103 (obviousness) than § 102 (anticipation).

The cited references at a glance

Per-reference analysis

1. US 4,697,144 A — Verify Electronics Limited (1987) — most relevant

Disclosure. Position-sensing apparatus with a single-phase energized primary (transmitter) coil system and an extended secondary (receiver) coil system arrayed along a path. The coils are arranged "series connected in pairs interspaced with other pairs as an array of coils along said path," and the specification states the coils of each pair are connected in reversed polarity so that — absent the moving member — they produce a nominally zero output. It expressly teaches that "the reversed polarity signals are generated by reversing the polarity of the secondary coils," and that the secondary array is "preferably of shallow depth such as provided by a printed circuit board." The moving member is an unenergized ferrite/conductor that changes coupling.

Why it matters. This is the clearest prior-art teaching of the core limitation of claim 1 — adjacent coils of the receiver (secondary) array carrying current in opposite directions, obtained by reversing coil polarity to cancel common-mode effects. That is functionally the same "twisted-pair / figure-8" anti-phase arrangement the '077 specification identifies as the reason the comparative design needed multiple layers.

Anticipation assessment (§ 102): Possibly anticipates the "opposite current direction" sub-limitation, but not claim 1 as a whole. US '144 lacks several claim-1 elements: no scale-side plurality of closed-loop connection coils that re-radiate flux at a predetermined spatial period (its position member is a passive flux-disturbing element, not a coupling-loop scale); no receiver coil whose first coils terminate on one substrate side face and second coils on the opposite side face; and no open-loop-coil/first-second-alternating structure as claimed. So it is best characterized as anticipating only the general concept, and as strong § 103 art against claim 1's anti-phase feature. It is the reference the examiner starred as most pertinent.

2 & 3. JP 2000-180209 A (Mitsutoyo) and US 6,329,813 B1 (Mitutoyo, Andermo) — same family

Disclosure. A reduced-offset induced-current absolute position transducer: a read head with a transmitter winding and overlapping receiver windings, and a scale with a plurality of flux coupling loops extending along the measuring axis. Critically, "Each of the receiver windings have loops with alternating winding directions… a first set of loops with a positive polarity and a second set of loops with a negative polarity… the EMF induced in the positive polarity loops has a polarity that is opposite to the polarity of the EMF induced in the negative polarity loops." The loops are nominally balanced so the direct transmitter-to-receiver coupling cancels. Receiver windings are spaced one-quarter wavelength apart to give quadrature outputs (two-phase), and the family includes multi-phase (three-receiver, 1/3-wavelength-offset) variants.

Why it matters. (a) It shows alternating/opposite current directions in adjacent receiver loops — the anti-phase feature. (b) It shows multiple phase-shifted receiver windings (quadrature; also 3-phase), which maps to claim 2's "each phase of a plurality of receiver coils is different from each other." (c) Its scale uses arrayed coupling loops coupling transmitter flux to receiver flux, i.e., the connection-coil concept.

Anticipation assessment (§ 102): Does not fully anticipate claim 1. The disclosure is built around a balanced positive/negative polarity-loop receiver winding, and — unlike '077 — the receiver structures here are described as formed with loop segments on first and second surfaces of a layer connected through vias (i.e., a multilayer/via implementation, see the related U.S. Pat. No. 5,936,399 description of the same family art). It does not teach the claim-1-specific single-face, open-loop, opposing-side-face terminal routing with no crossing (claims 1 and 3) or the "each transmitter coil surrounds each receiver coil" geometry (claim 2). Best treated as § 103 art, or § 102 art against a hypothetical broader claim not present here.

4 & 5. JP 2001-255108 A (Mitsutoyo) and US 2002/0011838 A1 (Mitutoyo, Miyata et al.) — same family

Disclosure. An induction-type transducer and electronic caliper with improved environmental durability — the measuring-side surface of the substrate carrying the flux generator, flux detector, and signal processor is made flat so that liquid entering the grid/scale gap does not permeate the substrate and damage the electrodes. It discusses inductive vs. capacitive transducers and the general inductive operating principle (exciting coils → scale coil induced current → detecting coil), including absolute-position variants with differing pitches λ1/λ2. U.S. App. 09/803,913 confirms the U.S. counterpart (inventor Miyata Toshiharu, filed 2001-03-13).

Anticipation assessment (§ 102): Not anticipatory of any claim. This family is directed to substrate sealing / flat-face construction and environmental robustness, not to the topology of the receiver coils. It discloses the generic transmitter/scale-coil/receiver architecture that is the preamble environment of claim 1, but none of the characterizing limitations: not the adjacent-coil opposite-current-direction requirement, and certainly not the open-loop, oppositely-terminated, non-crossing first/second coil layout. Relevant only as background/§ 103 context (and as evidence of the ordinary skill level and the known inductive architecture).

6. JP 2008-032546 A — "Induction-type displacement detection device" (Mitsutoyo, 2008)

Disclosure. An inductive displacement detector in which a plurality of flux coupling windings are arrayed on the scale along the measurement axis and a receiving winding with receiving loops arrayed along the measurement axis is on the sensor head; a "pair-loop" of length λ is used, each receiving loop being λ/2. (This is the general family of art around the EP 1 647 809 "Induction type displacement detector" line.)

Anticipation assessment (§ 102): Not anticipatory. It is directed to receiving-loop geometry / resolution and pitch (λ and λ/2 loop length, pair-loops), not to the opposite-current-direction requirement, the open-loop terminals on opposing side faces, or the crossing-free connection of claims 1 and 3. It is background art on receiver-loop layout and, at most, § 103 material on loop arrangement.

Consolidated § 102 / § 103 conclusion

Bottom line. Of the six references cited against US 10,996,077, US 4,697,144 A (Verify Electronics) is the most relevant — it squarely teaches reversed-polarity, series-connected adjacent secondary/receiver coils on a printed circuit board, i.e., the "opposite current direction" limitation. US 6,329,813 B1 / JP 2000-180209 A (Mitutoyo-Andermo) is next, teaching alternating-polarity receiver loops and multi-phase receiver windings with arrayed scale coupling loops. JP 2001-255108 A / US 2002/0011838 A1 and JP 2008-032546 A are background/architecture references (environmental sealing; receiving-loop geometry) that do not reach the characterizing limitations of claim 1.

No single reference in this set appears to anticipate claim 1, 2, or 3 under § 102. The realistic invalidity theory on this record is a § 103 combination (e.g., US '144's reversed-polarity coil teaching + Mitutoyo's arrayed coupling-loop scale/receiver art + a secondary reference for the opposing-side-face terminal routing), and even that combination does not obviously supply the claim-1/claim-3 crossing-free, single-face terminal routing features. That is consistent with the patent having issued after the 2021-03-02 office-action response.

Verification status / open items

• The six references are consistent with the citation list on the face of US 10,996,077 in the authoritative text; I verified each reference's identity, dates, and assignee against Google Patents / FreePatentsOnline / patent-PDF mirrors.
• I did not confirm the list directly from USPTO PatentCenter/PAIR, and the final tool calls (targeting JP 2008-032546 A and US 2002/0011838 A1 details) were terminated by a step limit — so my descriptions of #6 (JP 2008-032546 A) and the Miyata family are based on the evidence returned, not a complete read of those documents. Treat those two as lower-confidence on disclosure detail.
• For a definitive prosecution/IDS record and the examiner's actual applied-rejection mapping, pull the file wrapper from PatentCenter (App. 16/590,641).

I'll ground this analysis in the actual prior-art references of record, starting with the examiner-cited references listed on the patent page.

Obviousness Analysis — U.S. Patent No. 10,996,077 B2

"Electromagnetic induction type encoder" (Mitutoyo; Kubozono) under 35 U.S.C. § 103

Scope note. This analysis builds on the previously generated summary and litigation sections (which established the bibliographic record, claim set, and the absence of any identified litigation). It adds the § 103 analysis. All prior art discussed is drawn from the Prior Art / Citations section of the Google Patents page for this patent (www.patents.google.com/patent/[US10996077](/patent/US10996077)/en, fetched 2026-09-24). I have not retrieved the full text of every cited reference; where my characterization rests on partial text or a family-member equivalent, I flag it.

1. Framework

• Effective filing date / critical date: 2018-10-04 (JP 2018-189210 priority). Every cited reference predates this by 11–31 years, so all are § 102(a)(1)/(a)(2) art with no § 102(b) exception issues.
• Claims at issue: Claim 1 (sole independent), claim 2, claim 3 (both dependent).
• PHOSITA: A designer of inductive/induced-current position encoders with a B.S. in electrical or mechanical engineering and ~2–3 years' experience in PCB-based winding layout for calipers, linear scales, and micrometers.
• Prosecution posture: The 2021-03-02 "response to non-final office action" entry (recorded on the face of the patent) shows at least one substantive rejection was traversed before the 2021-03-11 Notice of Allowance. That allowance does not, of course, establish non-obviousness over art the examiner did not apply — and notably all six citations of record are listed as cited by examiner, i.e., the record appears to rest on a single-family, Mitutoyo-heavy art set.

Why this matters practically (context from the prior sections): The patent is Expired – Fee Related in the US (lapse effective 2025-05-04), so invalidity has little damages consequence here. It retains relevance for (a) the still-active family members JP 2020056754A, CN 111006698 B, DE 102019006773 A1, and (b) use of the disclosure as art against later Mitutoyo applications (e.g., JP 2025029383 A).

2. What is actually new — and what the specification concedes

The specification's Background is an applicant admission of the state of the art and of the problem to be solved:

receiver coils have a twisted-pair structure in which "8" shape lies down… wirings intersect with each other. Therefore, the twisted-pair structure has two or more wire layers in a printed substrate… when positional gap occurs between the two wire layers, an unintentional coil shape may be formed… it is difficult to apply a common correction value with respect to all products.

So the problem (multilayer registration error → unintended coil geometry → uncorrectable measurement error) is admitted prior-art knowledge. The asserted solution is a receiver coil that achieves the same opposite-adjacent-current ("twisted-pair") effect on one face, without intersection, by:

1. open-loop coils (not closed loops) alternately arrayed;
2. first coils terminating on one long side face (parallel to the measurement axis), second coils terminating on the opposite long side face; and
3. series connection in order at each of those two sides (claim 3: "without crossing").

That is the entire inventive delta over the cited art. The functional result — alternating current direction, common-mode/external-field rejection, nominally zero direct-coupling output — is squarely old.

3. The art of record, mapped to claim 1

Two observations from this chart:

• The examiner cited the same disclosure twice. JP 2000-180209 A shares the 1998-12-17 filing/priority date of US 6,329,813 B1 and the same title/assignee, so it appears to be the Japanese member of the same family (flagged as an inference — I did not verify a family link in a registry). Functionally, the art of record is four distinct disclosures: Verify '144; the Mitutoyo–Andermo reduced-offset family ('813 / JP 2000-180209, with EP 1 014 041 A1 and CIP US 6,400,138 B1 as corroborating family text); the Mitutoyo–Kawatoko "induction type transducer and electronic caliper" family (JP 2001-255108 A / US 2002/0011838 A1, whose US counterparts include US 6,501,264 B2 and US 6,522,129 B2); and JP 2008-032546 A.
• Mitutoyo's own later application describes the '813-type receiver winding in exactly the terms of the '077 comparative embodiment: "loop segments … formed on opposite sides of an insulating layer of the printed circuit board … linked through feed-throughs … to form alternating positive polarity loops and negative polarity loops" (US 2003/0090264 A1, describing the known reduced-offset transducer). This is strong corroboration that the multilayer crossover receiver was the acknowledged conventional design as of the '077 filing.

4. Grounds of rejection

Ground 1 (strongest): '813/JP 2000-180209 in view of '144

Claims 1 and 3.

'813 supplies every functional and most structural elements — including the opposite current direction limitation that the '077 specification treats as the "twisted-pair" benefit. The only gap is the open-loop / opposed-terminal / no-crossing layout.

'144 fills it and supplies the motivation. '144 teaches that the same reversed-polarity, balanced, nominally-zero-output coil array can be realized by series connection of coils in pairs along the path — i.e., polarity inversion by wiring, not by geometrically reversing winding direction or by crossing conductors between layers. A PHOSITA seeking to build the '813 receiver as a series chain of alternately-polarized loops would find in '144 the express teaching that alternate polarity is a connection choice. The natural, and in fact the only, way to series-connect a chain of alternately-reversed open loops without intersection on a single conductive layer is to bring out the two ends of successive like-polarity loops on opposite lateral edges and run the interconnecting traces along those edges — precisely claim 1's terminal placement and claim 3's "without crossing" limitation.

Motivation to combine (KSR factors):

• Same field, same problem: both are induced-current/inductive position transducers; both expressly address the balance between positive- and negative-polarity coils and the offset/"zero output" error that results from imperfect balance. '813 states that "fabrication tolerances always prevent perfect balance" and that residual offset results — the identical failure mode the '077 patent attributes to layer-to-layer misregistration.
• Predictable result: replacing a cross-over/feed-through connection with an in-order series connection on one face is a re-routing of known conductors with no change in operating principle; the electrical behavior is unchanged, and the benefit (no registration error between layers, no bonding step) follows mechanically.
• Design incentive / known alternative: the '077 Background itself concedes the industry knew the multilayer approach was problematic and that "it is difficult to apply a common correction value with respect to all products." A cost/accuracy-driven redesign to a single layer is the archetypal "design incentive" rationale.

Ground 2 (independent motivation for the single-layer re-routing): '813 in view of JP 2008-032546 A

Claims 1 and 3.

JP 2008-032546 A (Mitutoyo, "Induction-type displacement detection device") is of record and, per the retrieved text, expressly recognizes the very design-rule bottleneck the claim addresses: where the receiving winding must link multiple receiving loops along the relative-movement direction and plural phase-shifted receiving windings are stacked on a plurality of insulating plates, the problem becomes "the formation position of the contact portion for connecting the receiving loops", and using thin-film multilayer or high-density build-up substrates to ease that constraint raises manufacturing cost. That is an explicit, in-record teaching of (i) the problem, and (ii) the need for a receiver-winding layout that does not depend on inter-layer contacts. Combined with '813's alternating-polarity receiver loops, this supplies the articulated reason to arrive at an all-one-face layout — a stronger motivation showing than Ground 1 alone, because the reason is stated in a reference rather than inferred.

(Caveat: my JP 2008-032546 A characterization rests on the Google Patents abstract/description snippet retrieved; I did not obtain the full JP text, and the retrieved passage closely parallels US 7,196,510 B2 (Kawatoko, same Mitutoyo subject matter). Confirm against the JP document before relying on it in a filing.)

Ground 3 (alternative primary reference): '144 in view of '813 / RE37,490-type closed-loop scale

Claims 1 and 3.

If '144 is treated as the primary reference, it discloses the head-side architecture (single-phase transmitter, arrayed secondary/receiver coils with reversed-polarity adjacent coils, phase-representative output) and the moving coupling member. Its weakness as a primary reference is that the preferred moving member is a ferrite (a flux modulator), not closed-loop "connection coils." The '813/Andermo closed-loop coupling-loop scale — and, more generally, the Mitutoyo "reduced offset" family reflected in JP 2001-255108 A / US 2002/0011838 A1 (grid with exciting coils and a detecting coil, opposed to a scale coil; see US 6,501,264 B2 / US 6,522,129 B2) — supplies that element, and both are of record. Substituting closed conductive coupling loops for a ferrite member is a known, taught alternative coupling element in the same art, chosen for scale cost/robustness, with a predictable effect.

Ground 4: Claim 2 (two or more transmitter/receiver pairs; each receiver de-phased; each transmitter surrounding each receiver)

Claims 1 + 2.

• Plurality of receiver coils with mutually different phase: routine and expressly taught in the same record family. The reduced-offset Mitutoyo art discloses multiple receiver windings offset along the measurement axis (e.g., two windings spaced one-quarter wavelength for quadrature; a three-winding version offset by one-third wavelength, with the stated advantage of largely eliminating third-harmonic position error). JP 2001-255108 A / US 2002/0011838 A1 likewise discloses plural exciting/detecting coil sets at differing pitches (λ1, λ2) for absolute measurement. Motivation: direction discrimination, harmonic cancellation, absolute/coarse-fine measurement — all stated in the references themselves.
• Each transmitter coil surrounding each receiver coil: this is the conventional geometry of the record art. '144 expressly contemplates a primary coil system that "lays over or around the coils of the secondary coil system." The Mitutoyo transducer family places the detecting coil between/surrounded by the exciting coils.

Ground 5: Claim 3

Claim 3 adds only "connected without crossing" — the direct and intended consequence of the single-layer routing scheme relied on in Grounds 1–2. It rises and falls with claim 1; it adds no separate inventive concept.

5. Where a patent owner would push back

1. No reference expressly discloses the opposed-side terminal routing. '813 arguably teaches away in the sense that its receiver winding is built with loop segments on two sides of an insulating layer joined by feed-throughs. A challenger needs the "re-routing of a known series chain" argument, plus JP 2008-032546's stated contact-formation/cost problem, to bridge to the claim. Without Ground 2's motivation showing, the ground is noticeably weaker.
2. "Open loop coil" is a term of degree. The '077 open loop (61a/62a) plus edge wiring (63/64) forms a closed current path overall; a patent owner could argue the cited art's closed coupling loops and sinusoidal receiver loops are structurally distinct. Expect a claim-construction fight rather than a pure anticipation fight.
3. No objective indicia in the record. Nothing in the prior sections shows commercial success, copying, or industry praise with nexus to this claim. Conversely, the patent's early maintenance-fee lapse (2025) undercuts a long-felt-need/success narrative.
4. Inference risk on family equivalences. My treatment of JP 2000-180209 A as the JP member of the '813 family, and of JP 2001-255108 A / US 2002/0011838 A1 as the Kawatoko transducer family, is an inference from matched filing dates, titles, and assignees — not a registry confirmation. Verify via Espacenet INPADOC before filing.

6. Bottom line

• On the record as it stands, claim 1 is very likely obvious over US 6,329,813 B1 (and/or JP 2000-180209 A) in view of US 4,697,144 A, with JP 2008-032546 A supplying an independent, in-record motivation to eliminate the inter-layer contact/feed-through routing. Claim 3 falls with claim 1. Claim 2 is additionally obvious over the multi-phase receiver disclosures of the same Mitutoyo family (and JP 2001-255108 A / US 2002/0011838 A1).
• The one limitation with no clean textual hit in the retrieved art is the opposed-side terminal placement of the open-loop coils. That limitation is a routing geometry, and the combination case for it rests on (a) '144's teach-an-alternate-polarity-by-connection disclosure and (b) JP 2008-032546's statement of the inter-layer contact problem. This is a strong but not airtight case; it is the pivot point for any IPR petition or invalidity contention.
• Verification items before relying on this: (1) full-text/image review of JP 2000-180209 A, JP 2001-255108 A, JP 2008-032546 A; (2) the '077 file wrapper (the 2021-03-02 response and the underlying non-final rejection) to see whether the examiner already addressed single-layer receiver routing; (3) an INPADOC family check to confirm the JP/US equivalences I flagged; (4) a figure-level review of '813's read head to confirm how the receiver loops are terminated (my characterization is text-based only). I could not complete the interactive docket/database queries noted in the earlier sections, and I make no representation about art beyond the six citations of record.