US 11226245

I'll search for litigation/docket activity and USPTO records for this specific patent number.

Let me run additional targeted searches for litigation and USPTO/PTAB records specific to this patent.

Summary: US Patent No. 11,226,245

Sourcing note: My search did not return any USPTO litigation record, PTAB proceeding, or CAFC 2026 appeal docket tied to this specific patent number. The only authoritative matches were the patent's own record (Google Patents/PubChem) and the EPO family member. Several search hits contained the digit string "11226245" but were unrelated — e.g., a Travis County, TX jury-panel list ("11226245 DELIA TREVINO"), a Brazilian corporate registry entry ("11226245 SOLAR POWER BRASIL S.A."), and a Vietnamese/aggregator listing. These are coincidental number collisions, not this patent. I flag this because the instruction was to search literally and not conflate similar identifiers.

Bibliographic data (authoritative)

Abstract (as published)

A force sensor includes a frame and an oscillation structure which has arms and can oscillate freely in the frame. The arms are fixed to suspension frame regions and run transverse to one another at least in sections. At least one conductor extends along at least two arms. An AC voltage can be applied to the at least one conductor to excite at least one oscillation mode of the oscillation structure with a resonant frequency using Lorentz force. The force sensor is designed such that the suspension regions are at least partially spatially displaced relative to one another when a force is applied to the frame, that the magnitude of the spatial displacement of the suspension regions depends on the magnitude of the force, and that the spatial displacement of the suspension regions causes detuning of the resonant frequency, the magnitude of which depends on the spatial displacement magnitude.

Independent claims

The patent has 26 claims, with only one independent claim — claim 1. Every other claim (2–25) depends, directly or indirectly, on claim 1, and claim 26 is a dependent claim directed to a prosthesis comprising the system of claim 1. There is no second independent claim.

Claim 1 (sole independent claim) — plain language:
A system built around a MEMS force sensor. Four key elements:

1. Frame + free-standing oscillation structure. A frame surrounds an oscillation structure with multiple arms that can oscillate freely inside the frame. The arms attach to "suspension regions" of the frame and run transverse (crosswise) to one another at least in places.
2. Force-to-displacement-to-detuning mechanism. When a force is applied to the frame, the suspension regions shift position relative to one another. The size of that displacement scales with the force magnitude, and the displacement de-tunes (shifts) the resonance frequency of an oscillation mode — with the amount of de-tuning scaling with the displacement. So force magnitude is inferred from a frequency shift.
3. Lorentz-force drive. At least one conductor (conducting means) runs along at least two arms, letting current (moving charge carriers) flow between two suspension regions. Applying an AC voltage to that conductor, with the structure in a magnetic field, excites an oscillation mode at its resonance frequency via the Lorentz force.
4. Read-out + control + magnetic field. The system includes read-out means to determine the resonance frequency; a control unit wired to the conductor (to apply the AC drive) and to the read-out means; the control unit is configured to apply at least one AC pulse having a frequency bandwidth that spans the resonance frequency of at least one oscillation mode (a "chirp"/broadband pulse technique, rather than stepping through single frequencies); and the system includes means for generating the magnetic field.

Dependent-claim themes (brief)

• Geometry: suspension regions at frame corners; four corners in a plane forming a rectangle/square (claims 2–5); arms numbering a whole multiple of four, preferably exactly four (8–9); meander-shaped frame sections, preferably between suspension regions (6–7).
• Coupling element: arms mechanically coupled by a coupling element (edges, polygonal/four-cornered/rectangular/square, arms fixed at corner points) (10–18).
• Temperature compensation: arms mounted via meander-shaped temperature-compensation structures (19).
• Materials/fabrication: frame and oscillation structure one-piece silicon, preferably mono-crystalline (20–21).
• Drive/operation: two conductors driven counter-phase (22); sequential pulses targeting different oscillation modes (23); permanent magnet and/or Helmholtz coil (24); excitation of in-plane oscillations (25).
• Application: a prosthesis comprising the system (26).

Uncertainty / caveats

• No litigation or appeal found. I could not locate any district-court case, PTAB petition (IPR/PGR), or Federal Circuit 2026 docket involving US 11,226,245. If you have a specific docket number, I can re-query against it — but absent that, the record supports the conclusion that this patent was never asserted in a U.S. proceeding found in public sources.
• Status nuance. Public records describe the patent as expired for non-payment of the 3.5-year maintenance fee (lapse effective 2026-01-18). Note the record's "adjusted expiration 2037-07-29" is a term-calculation figure (20 years from filing plus any adjustment), not a statement that the patent remains in force; the maintenance-fee lapse terminates enforceability earlier unless reinstatement/petition revives it.
• All bibliographic and claim details above are taken from the authoritative full patent text provided, corroborated by the PubChem patent record; I did not rely on search results that conflicted with that text.

I'll search for litigation involving US Patent 11,226,245.

Let me run more targeted searches on litigation databases and the specific patent.

Summary of Findings: Litigation Involving U.S. Patent No. 11,226,245

No litigation involving U.S. Patent No. 11,226,245 has been found.

I searched litigation-focused resources (including the Unified Patents litigation portal, PACER-derived docket aggregators such as Justia Dockets and UniCourt, CourtListener, and general web sources), querying the exact number "11226245" / "11,226,245." No case in which this patent was asserted (as plaintiff's patent-in-suit) or challenged (as defendant's counterclaim patent) was identified.

Patent identification (to avoid a mis-identification)

The patent is:

• Patent No.: US 11,226,245 B2 — "Force sensor"
• Application No.: US 16/498,437 (National Stage of PCT/AT2017/060082, filed 2017-03-31)
• Inventors: Alexander DABSCH; Franz KEPLINGER; Christoph ROSENBERG
• Assignee: Technische Universitaet Wien (Austria)
• Granted: 2022-01-18
• Status: Expired — Fee Related; expired for failure to pay maintenance fees (lapse records dated 2026-02-23; effective date 2026-01-18)
• Family: EP3601973B1 (active), WO2018176069A1, US20210116313A1

Important caution — a near-miss that is NOT this patent

Search results surfaced Sandpiper CDN, LLC v. Google LLC, No. 2:24-cv-03951 (C.D. Cal., filed 2024-05-10), in which a "'112 Patent" is asserted. That '112 patent is U.S. Patent No. 9,021,112, one of several content-delivery-network patents in that case (the others including U.S. Patents 8,478,903; 8,595,778; 8,645,517; 8,719,886; and 10,924,573 — all held by Sandpiper CDN, LLC). It is not U.S. 11,226,245. Similarly, various PTAB documents referencing a "'112 patent" (e.g., the IPR concerning UCT/Lenovo or the Kubota '386 petition) concern different patents entirely. Per the strict rule, I am not auto-correcting any identifier; I note only that these are distinct patents.

Related adversarial proceedings (for completeness, and also none found)

• IPR / PGR: No inter partes review, post-grant review, or reexamination of U.S. 11,226,245 was found.
• ITC (Section 337): None found.
• CAFC appeals: None found.
• Foreign (EP counterpart EP3601973B1): No opposition or litigation identified in the search results.

Confidence and caveats

• I am highly confident that the widely-indexed litigation databases contain no case asserting U.S. 11,226,245. The patent is a university-owned MEMS force-sensor patent with no apparent commercial enforcement campaign.
• Caveat: My search tools were limited in this session (the environment cut off further queries), so I could not exhaustively verify every PACER district docket or every foreign forum. A negative result is not proof of absence. For a definitive litigation check, I recommend running the patent number through:
  • Lex Machina / Docket Navigator / Unified Patents Portal (docket-level, patent-number search), and
  • USPTO Patent Trial and Appeal Board (PTAB) and USPTO Assignment records, and
  • PACER for any case filed under an NPE/plaintiff that purchased the patent after Technische Universitaet Wien's rights lapsed.

Bottom line: Based on the available evidence, there is no known litigation involving U.S. Patent No. 11,226,245. The only " '112 patent" litigation appearing in search results refers to U.S. Patent No. 9,021,112 (Sandpiper CDN v. Google), which is a different patent.

AIA Trial Proceedings — US Patent No. 11,226,245 ("Force sensor," Technische Universitaet Wien)

Sourcing note on identifications. The digit strings "245," "'245," and "11,248,245" recur across PTAB papers and are a live false-positive trap. Two that surfaced in my search are not this patent and are flagged here so nobody repeats the error: (1) the "'245 patent" discussed in an Advanced Bionics/§ 325(d) jojoba-ester dispute is a different document (the paper is captioned "Patent 11,248,245 B2" — a different number from 11,226,245); and (2) hits citing U.S. Pat. No. 9,142,400 and "245" figures in a LED-fixture petition likewise concern unrelated assets. Neither is evidence of anything filed against US 11,226,245.

Proceedings overview

There are zero AIA trial proceedings on file against US 11,226,245 — no IPR, no PGR, and no CBM — as returned by the US Open Data Portal structured "PTAB proceedings on file" block supplied with this analysis, corroborated by independent web searching that produced no petition, institution decision, or Final Written Decision naming this patent, its application number 16/498,437, its inventors (DABSCH / KEPLINGER / ROSENBERG), or its owner (TU Wien). The bottom-line defensive posture for a defendant is therefore not "hardened by surviving infringement challenges" and not "claims already canceled" — it is that no third party has ever put this patent's validity at issue in a U.S. post-grant forum, which, combined with the maintenance-fee lapse making it unenforceable as of 2026-01-18, means there is no PTAB record to attack or rely on either way.

No proceedings to list

The requested per-proceeding format (proceeding number, petitioner, panel, grounds, institution decision, FWD, settlement, appeal) cannot be populated, and I will not populate it speculatively. There is no proceeding number to report. Inventing one — or importing a real proceeding number from the unrelated "245" documents above — would be a fabrication, and you should treat any AIA proceeding number you later see attached to this patent as requiring independent verification at PTAB E2E before it is relied on.

What the null result does and does not tell you:

• Does tell you: The patent was prosecuted, granted 2022-01-18, and then allowed to lapse for non-payment of the 3.5-year maintenance fee (lapse recorded 2026-02-23, effective 2026-01-18). A patent that is never asserted in litigation essentially never attracts an IPR — IPR petitions are filed defensively against live assertions. The absence of any petition is consistent with, and reinforces, the conclusion that TU Wien never asserted this patent in a U.S. court. The owner's own commercialization materials support that reading: TU Wien's technology-transfer listing for this sensor family ("PikoSens," ref. M032/2016) offered it as "R&D – Cooperation License Agreement / Patent selling," i.e., the asset was marketed for licensing or sale, not enforced.
• Does not tell you: That the claims are valid, that no § 112 or § 102 issue exists, or that a former licensee/collaborator hasn't quietly taken a license rather than fight. Absence of PTAB activity is not a validity endorsement. It is simply a no-assertion signal.

Strategic summary

Claim status across all forums: 26 claims — 0 canceled, 0 sustained-by-IPR, 26 untested. Because there has been no FWD, there is no claim-by-claim disposition to report. For the record, the patent has one independent claim (claim 1), and every other claim (2–25) depends directly or indirectly on it; claim 26 is a dependent claim to a prosthesis comprising the system of claim 1. That claim architecture is worth noting for any future attack: killing claim 1 would take the entire patent with it, so a single, clean § 103 ground on the Lorentz-drive-plus-bandwidth-pulse limitations would be dispositive across all 26 claims. (To be clear: this is an observation about leverage, not a finding that any such ground exists — I have not substantively evaluated validity here.)

Estoppel landscape: none exists. Because no IPR or PGR was ever instituted, 35 U.S.C. § 315(e)(2) estoppel has never attached to anyone, and no petitioner or privy is barred from raising any ground. There is also no Sotera-type stipulation or Fintiv/§ 314(a) discretionary-denial record on this patent to constrain anyone. Practically, however, this is largely academic: with the patent expired for fee non-payment, there is no live assertion against which an estoppel analysis would matter.

Pattern signals: none. There is no repeat petitioner (there is no petitioner at all), no PTAB appeal history to the Federal Circuit, and no sign of a defensive aggregator such as Unified Patents ever touching this patent. TU Wien's posture is that of a university technology-transfer office — it pursued prosecution but did not litigate, and the patent has now lapsed. The single live legal-status fact that dominates everything: the patent is expired for failure to pay maintenance fees (lapse effective 2026-01-18), with a recorded adjusted-expiration date of 2037-07-29 that reflects term calculation, not enforceability.

Recommended next steps

1. If you have received a demand letter citing US 11,226,245, verify the patent's status first. The public record shows a maintenance-fee lapse, so any assertion of live rights requires an explanation (reinstatement under 37 CFR 1.378 with an unintentional-delay showing and surcharge is the only path back; it is time-limited, and I would verify the current deadline rules rather than rely on memory). An assertion of an expired patent is itself actionable under 35 U.S.C. § 292 in appropriate circumstances.
2. If someone hands you an IPR/PGR number purportedly against this patent, treat it as unverified until you pull it from PTAB E2E under the patent's application number 16/498,437. Given the "245"/"11,248,245" collisions documented above, a number that superficially matches is more likely a different patent than a missed proceeding.
3. If there is in fact a pending parallel district-court case you are defending (which the public record does not show), then the PTAB absence is an opportunity, not a defense: with § 315(b)'s one-year bar and § 315(e)(2) estoppel both un-triggered and no prior Fintiv investment, an IPR could be filed on a clean slate. Whether it is worth the filing fee against a fee-lapsed patent is a business call, not a legal one.
4. Do not represent to a court or an adversary that this patent "survived IPR" or "was invalidated in IPR." Neither happened. The accurate statement is that no AIA trial proceeding has ever been filed against US 11,226,245, and that the patent is expired for non-payment of maintenance fees effective 2026-01-18.

Confidence and limits. I am highly confident that the ODP-derived proceedings list is empty and that no petition exists in readily searchable public sources — the searches returned only number collisions and the patent's own bibliographic records (e.g., the PubChem record for US-11226245-B2 and the TU Wien "PikoSens" technology offer). I cannot rule out a very recently filed petition not yet indexed by ODP or by the search engine, and I would not claim otherwise; if you have a specific docket or petition number, I can re-query against it directly.

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

Ownership & Assignment Analysis — US 11,226,245 B2 ("Force sensor")

Verification note up front: I located exactly one recorded assignment in the chain, plus the prosecution correspondence agent. I could not independently open the Assignment Center record (assignmentcenter.uspto.gov is an interactive search that my tooling cannot query directly), so reel/frame and party data below are taken from the patent's own legal-events record in the authoritative full text you supplied, corroborated by the EPO/Google Patents family display. Where something is not verifiable, I say so rather than filling it in.

Inventors

Employer at time of filing: all three were TU Wien-affiliated (inventors' rights held by the university, which is confirmed by the single assignment below). This is a classic university-inventor chain, not a corporate R&D chain.

Unusual patterns? None of the classic departure red flags:

• No evidence any inventor assigned away from, or left, TU Wien within 12 months of filing (2017-03-31). Dabsch was still at TU Wien in 2020 (WU Vienna business-plan project lists him at alexander.dabsch@tuwien.ac.at) and his 2020 dissertation at TU Wien lists this PCT application as the basis of the work.
• The inventors assigned to their own employer, not to a third-party acquirer — the opposite of a fire-sale posture.

Original assignee

Technische Universitaet Wien (Vienna University of Technology, Karlsplatz 13, 1040 Wien, Austria) — named on the issued patent and confirmed as the EPO (73) applicant/patentee for the sibling EP3601973B1.

• Primary line of business: public research university / academic research institution. Not a sensor manufacturer.
• Product embodying the claims? No evidence of a shipped commercial product. The technology was marketed under the "PikoSens" banner via TU Wien Forschungs- und Transfersupport as a working prototype (technology offer TUWien_2016-032, reference M032/2016, "DEVELOPMENT STATUS: Working Prototype"). The offer explicitly lists commercialization options as "R&D – Cooperation License Agreement / Patent selling," i.e., the university was openly seeking to license or sell, not to manufacture.
• A 2019/2020 WU Vienna student business-plan project explored spinning PikoSens out as a licensor company (contacts with Infineon, AMS, IST Cube), but I found no evidence a spin-out entity was ever incorporated, and no assignee other than TU Wien appears on the record. Treat "PikoSens the company" as unformed/unconfirmed.
• Current status: TU Wien is an operating institution (alive and well). The patent, however, is not — see status note below.

Assignment timeline

Chronological list of recorded assignments:

• 2019-09-27 (executed) / recorded 2019-10-01 — Reel 050582/0064
  • Conveyance: Assignment — "ASSIGNMENT OF INTEREST (SEE DOCUMENT FOR DETAILS)"
  • Assignor: DABSCH, Alexander; KEPLINGER, Franz; ROSENBERG, Christoph (jointly)
  • Assignee: TECHNISCHE UNIVERSITAET WIEN, Austria
  • Correspondent: ⚠️ Not determinable from the sources available to me. The Assignment Center record's correspondent-of-record field is not reproduced in the Google Patents legal-events feed. For context only — and not as a substitute for the assignment correspondent — the prosecution correspondence address of record for this application is Collard & Roe, P.C. ("Agent: Collard & Roe, P.C.," US 2021/0116313 A1). Do not treat that as the recording correspondent without direct confirmation. Since this is a single, one-off appearance, the "repeat correspondent" signal is not assessable and I will not score it.
  • Context: Inventor-to-employer assignment, executed contemporaneously with U.S. national-stage entry of PCT/AT2017/060082 (national stage entered 2019-10-01; "fee payment procedure / entity status" events recorded 2019-09-27 and 2019-10-09). Routine university IP housekeeping — not a transfer, monetization event, or reorg.

No further assignments are recorded. There is no post-issuance assignment, no transfer to an IP-holding LLC, no security agreement, no merger, no license recordation, and no change-of-name entry. The record runs from the three inventors straight to the university and stops there.

Status consequence (from the legal-events record): maintenance-fee reminder mailed 2025-09-08; "LAPSE FOR FAILURE TO PAY MAINTENANCE FEES" recorded 2026-02-23, effective 2026-01-18 (37 CFR 1.362). The patent is listed as "Expired – Fee Related." The "adjusted expiration 2037-07-29" figure is a term calculation, not a statement of enforceability.

Timeline diagram

timeline
    title Ownership of US 11226245
    2017 : Priority and PCT filing by TU Wien
    2019 : Inventors assign rights to TU Wien
         : US national stage entered
    2021 : Pre-grant publication
    2022 : Patent granted to TU Wien
    2026 : Lapsed for unpaid maintenance fee

NPE / troll-pattern signals

Verdict

Insufficient data — under your rubric's own definition ("no records, or only the original assignment"). The entire recorded chain is one inventor→employer assignment at reel 050582/0064 (executed 2019-09-27, recorded 2019-10-01), leaving Technische Universitaet Wien as the sole owner for the patent's entire life. There are zero NPE signals: no shell transfer, no named asserter, no cascading or pre-litigation transfers, no privateering, no defensive-aggregator endpoint, and no litigation or PTAB record tying to this number.

Substantive read (the affirmative finding): this is a non-asserting academic-held patent that was never monetized through the U.S. patent-assertion ecosystem. TU Wien marketed the underlying "PikoSens" technology for licensing or outright sale and obtained only a working prototype — no commercial product — then let the U.S. patent lapse for non-payment of the maintenance fee effective 2026-01-18 (recorded 2026-02-23). Abandonment-by-nonpayment is close to the strongest possible evidence that no assertion campaign was ever contemplated: an NPE chain would not let its asset expire for a missed fee while holding no other U.S. family member for this subject matter. One caveat on completeness: because I could not render the Assignment Center UI directly, I cannot rule out an unindexed license or security recordation that never reached the Google Patents legal-events feed; if you need a belt-and-suspenders check, search by application number 16/498,437 and by patent number at the USPTO Assignment Center, and confirm the correspondent field on reel 050582/0064.

Verify at: https://assignmentcenter.uspto.gov/ (search "11226245" or application "16/498,437") — mirrored at https://assignment.uspto.gov/patent/index.html

Cross-reference flag: No contradiction with the previously generated sections. That section's finding of no litigation/PTAB/appeal is fully consistent with the ownership picture here — the absence of any transfer-out is the reason no assertion record exists. Both point the same direction: an academic patent that was never fed into the assertion market.

I'll ground each cited reference with targeted searches, then map them to the claims.

Now the remaining cited references and the USPTO record itself.

Prior Art Analysis — US Patent No. 11,226,245 ("Force Sensor")

Scope and sourcing note. I searched for this specific number and the record that came back is the patent's own front page and its cited-reference list. I did not retrieve the underlying USPTO Office Action / International Search Report (the only prosecution document of record listed is the International Search Report in PCT/AT2017/060082, dated Dec. 12, 2017, per the patent's "Non-Patent Citations"), so the §102 mapping below is built from each reference's own disclosure as retrieved vs. the text of the '245 claims — not from an examiner's stated rejection. Where a date or detail is uncertain, I say so rather than filling it in.

A caution on anticipation (35 U.S.C. §102). As established in the earlier summary, US 11,226,245 has one independent claim (claim 1); claims 2–26 all depend (directly or indirectly) on claim 1. A dependent claim incorporates every limitation of the claim from which it depends. Therefore a reference cannot "anticipate" any claim of this patent unless it discloses all elements of claim 1. On the record retrieved, none of the six cited references discloses all elements of claim 1, so none anticipates any claim — the honest characterization is that these references are §103 obviousness material and, for a few, single-limitation material, not §102 anticipatory art. I give the per-element breakdown so that conclusion is auditable.

1. The six cited references on the face of US 11,226,245

Marker note: the Google Patents record applies an examiner-citation marker to US20080210005A1, US20140026686A1 and US20170252187A1; the two Japanese/older U.S. items and WO2011163058A2 appear without it. I flag this as a rendering of the record, not as a verified statement of which art the examiner substantively relied on.

Because the '245 patent's effective filing date is 2017-03-31 (post-AIA), AIA §102 governs. Items 1–5 are available under §102(a)(1) (publicly available before that date). Item 6 was published 2017-09-07 (after the '245 filing date), so it is not §102(a)(1) art; it is available only under §102(a)(2) as a U.S. application publication effectively filed (2017-03-03) before 2017-03-31.

2. Per-reference analysis

Reference 1 — JPS61194325A (Shinko Denshi K.K.), "Force converting mechanism"

• Full citation: JP S61-194325 A; appl. filed 1985-02-25; laid open 1986-08-28; applicant Shinko Denshi K.K.; inventors Nishiguchi Yuzuru, Suzuki Nobuo.
• Description (per retrieved abstract): An integral force-converting mechanism in which a central link is formed as a vibration-detection vibrator (a tuning-fork vibrator) connected through thin-walled bending parts/links. An applied external force F on an upper connection part generates a tension H = F·tan θ on the tuning fork; the resulting increase in the vibrator's natural frequency is measured to determine the magnitude of the applied force. So the reference discloses the concept of inferring force from a shift in a mechanical resonance frequency.
• §102 assessment: Does not disclose (i) a frame with suspension regions that displace relative to one another under load; (ii) a conductor running along at least two transversely oriented arms; (iii) Lorentz-force excitation from an AC voltage in a magnetic field; (iv) read-out means + control unit applying a broadband AC pulse spanning the resonance; or (v) means for generating the magnetic field. → No claim anticipated.

Reference 2 — US5095763A (Delatorre), "Load-sensitive resonator beam transducer"

• Full citation: US 5,095,763 A; filed 1990-12-03; issued 1992-03-17; inventor/assignee Leroy C. Delatorre.
• Description: A vibratory force transducer with an elongate vibratory beam (or two beams coupled as a double-ended tuning fork), rectangular cross-section, with integral "tab" sections that change the moment of inertia. The beam is driven by electrical excitation to resonate at f₁, and an axially applied load F changes the resonant frequency as a function of the load (f_t = f_to(1+S_et)·…); dimensional selection avoids spurious modes. Again a force→resonant-frequency-shift device.
• §102 assessment: Discloses electrical resonant drive and load-dependent detuning, but not the frame/relative-suspension-displacement architecture, not a multi-arm transverse oscillation structure, not Lorentz-force actuation via a current-carrying track in a magnetic field, and not the control-unit/broadband-pulse or magnet-generation elements. → No claim anticipated.

Reference 3 — US20080210005A1 / US 7,707,886 B2 (Thales), "Micro-Machined Gyrometric Sensor…"

• Full citation: US 2008/0210005 A1, published 2008-09-04 (granted US 7,707,886 B2, 2010-05-04); PCT filed 2006-06-19 (PCT/EP2006/063306); priority FR 0507144, 2005-07-05; assignee Thales; inventors Chaumet, Rougeot, Willemin, Le Verrier.
• Description: A MEMS gyroscope micromachined in a silicon-on-insulator wafer: two symmetric moving assemblies coupled by a coupling structure of outer frames plus a linking bar, with moving mass/intermediate frame, flexure/linking arms, and interdigitated capacitive combs for excitation and detection. The excitation voltage is an AC voltage at/near the mechanical resonance frequency; SOI fabrication and conductive (doped) silicon are described.
• §102 assessment: Overlaps structurally with several dependent claim concepts — coupled arms, coupling/frame elements, one-piece silicon/SOI fabrication (cf. claim 1's structural context and claims 10, 20–21) — but the drive is electrostatic (capacitive comb), not Lorentz force; it is an angular-rate sensor, not a force sensor that infers force from relative displacement of suspension regions; and it has no broadband-pulse control or magnet means. Because every dependent claim incorporates claim 1, and claim 1 is not disclosed, → No claim anticipated. Best characterized as background art for the MEMS frame/coupling/silicon limitations.

Reference 4 — WO2011163058A2 (Univ. of Illinois), "Cell mass measurement and apparatus"

Reference 5 — US20140026686A1 / US 9,250,113 B2 (Bashir et al.), "Cell Mass Measurement and Apparatus"

(These two are the same invention — WO publication and its U.S. national-stage publication/grant — so they are analyzed together; they are the closest of the cited art.)

• Full citations: WO 2011/163058 A2, published 2011-12-29, PCT/US2011/040736 filed 2011-06-16, priority US provisional 61/356,848 (2010-06-21). US 2014/0026686 A1, published 2014-01-30, App. 13/805,623; granted US 9,250,113 B2 on 2016-02-02; assignee The Board of Trustees of the University of Illinois; inventors Bashir, Park, Millet, Hsia, Aluru.
• Description: A resonant mass sensor comprising a microfabricated suspended platform supported by three or more tethers, designed for uniform vibration amplitude. Critically, the disclosure includes: a metal layer (e.g., gold, platinum) deposited over the suspended platform and tethers; one or more permanent magnets arranged so the magnetic field is parallel to the measuring surface; and the suspended platform induced to oscillate by passing a current across it (i.e., a Lorentz-force drive in a magnetic field). It also lists electrostatic and piezoelectric alternatives, and detection by optical, capacitive, piezoelectric or piezoresistive means; suspended platform and tethers may be silicon/SOI-based.
• §102 assessment: This is the only cited reference that discloses the Lorentz-force excitation principle with a conductor over a microfabricated resonator in a magnetic field, plus magnet means and optical/capacitive read-out — i.e., it touches the substance of claim 1 elements (d), (e), (f) and (i), and the magnet limitation of claim 24 and the silicon limitation of claims 20–21. It nevertheless does not disclose: a frame with suspension regions that displace relative to one another when an external force is applied, with detuning magnitude tied to that displacement (the '245 measures force via suspension-region displacement; Bashir measures mass via frequency shift of a platform); the multi-arm, transversely oriented oscillation structure fixed on suspension regions; or the control unit applying a broadband AC pulse spanning the resonance (claim 1's final drive limitation). → No claim anticipated; this is the strongest §103 combination candidate.

Reference 6 — US20170252187A1 (Orthosensor Inc.), "Orthopedic leg alignment system and method"

• Full citation: US 2017/0252187 A1, published 2017-09-07, App. 15/449,892 filed 2017-03-03 (some sources list 2017-03-02); priority 2016-03-02/03; assignee Orthosensor Inc.; inventors Chapman, Van Citters, Goodchild.
• Description: An orthopedic measurement system using a tri-axial gyroscope placed in a tibial insert/prosthetic component to measure leg alignment relative to the mechanical axis, with the gyroscope coupled to a computer that calculates alignment from angular-velocity data.
• §102 assessment: Relevant only as application-area background to claim 26 (a "prosthesis comprising the system according to claim 1"). It is a gyroscope-based alignment system — it discloses neither the '245 force sensor of claim 1 nor any of the frame/arm/Lorentz-drive/detuning elements. Because claim 26 incorporates claim 1, a system lacking claim 1's sensor cannot anticipate claim 26. Note also the date posture: published after the '245 filing date, so usable only under §102(a)(2) (effectively filed 2017-03-03). → No claim anticipated.

3. Bottom line

• Most relevant prior art for US 11,226,245: US 2014/0026686 A1 (Bashir et al., Univ. of Illinois), and its co-family WO 2011/163058 A2 / US 9,250,113 B2. It is the only cited reference disclosing Lorentz-force (current-in-magnetic-field) excitation of a microfabricated silicon resonator using a metal conductor layer, plus permanent-magnet field generation and optical/capacitive read-out — i.e., it maps onto the drive/read-out/magnet aspects of claim 1 and to claims 20–21, 24 (and 22 by analogy). It is nonetheless a mass sensor, not a force sensor read out through relative displacement of frame suspension regions, and it lacks the broadband-pulse drive limitation.
• Secondary relevance: US 2008/0210005 A1 (Thales) for the MEMS frame/coupling structure, flexure arms and SOI-silicon fabrication; US 5,095,763 (Delatorre) and JP S61-194325 (Shinko Denshi) for the general concept of deriving an external force from a shift in a resonantly driven element's natural/resonance frequency; US 2017/0252187 (Orthosensor) as prosthetics/orthopedics background for claim 26.
• No §102 anticipation: No cited reference — individually or as the record now stands — discloses every limitation of sole independent claim 1 as arranged in that claim, so no reference anticipates claim 1 or, a fortiori, any dependent claim 2–26. The useful attack vector for this art is §103 (e.g., Bashir's Lorentz-driven silicon resonator combined with a force-to-resonance-shift transducer such as Delatorre or Shinko Denshi, and a frame/coupling MEMS structure as in Thales).

Caveat / open item. I could not retrieve the actual Office Action or the Dec. 12, 2017 International Search Report to confirm which of these references the examiner substantively relied upon or on what theory. If you can supply the ISR or the U.S. Office Action, I can re-map the art against the examiner's stated grounds. If a search result had conflicted with the authoritative patent text, I would have flagged it — none did.

I'll analyze the obviousness question using the prior art identified on this patent's page. First, let me verify the disclosures of the key references with targeted searches.

Let me verify the remaining cited references and the closely-related "similar documents" that bear on Lorentz-force drive and resonant sensing.

Obviousness Analysis — US 11,226,245 B2 ("Force sensor") under 35 U.S.C. § 103

Scope note / sourcing. Per your instruction I analyzed only the prior art listed in the Prior Art section of this patent's page (the five examiner/third-party citations plus the ISR non-patent citation). I verified the disclosures of four of the five cited references by search (Delatorre, Shinko, Thales, Bashir, Orthosensor). Two verification queries hit my search-step ceiling, so a few mechanistic details below rely on the fetched patent text and on general knowledge, and I flag those explicitly. Where the full patent text and search results conflict, I followed the text.

Threshold reality check (flag for the record). The patent already lapsed for non-payment of maintenance fees (recorded 2026-02-23, effective 2026-01-18), so it is unenforceable unless revived. An invalidity question is therefore largely academic as of today — but I analyze it as requested.

1. Governing framework

• Graham v. John Deere factors: (1) scope and content of the prior art; (2) differences between the prior art and the claims; (3) level of ordinary skill; (4) secondary considerations.
• KSR Int'l v. Teleflex (2007): a combination is obvious where the improvement is the "predictable use of prior-art elements according to their established functions," or where a "known technique is used to improve a similar device." Explicit "teaching, suggestion, motivation" is not required.
• MPEP 2143 / In re Keller: each reference must be read for what it fairly teaches; the combination, not each reference in isolation, is judged.

POSITA (proposed): a person with an M.S. or Ph.D. in mechanical/electrical engineering or applied physics and 3–5 years' experience designing micromachined (MEMS) resonant sensors, including SOI microfabrication, resonant drive/detection (electrostatic, magnetic/Lorentz, and optical), and frequency-domain instrumentation. I note the patent itself targets MEMS-level sensitivity ("in particular as a MEMS… to measure very small forces… in the nN range or even the pN range"), which supports this level of skill.

Statutory-timing check on the references

Orthosensor is the one reference whose publication postdates the filing date; it still qualifies under §102(a)(2) because it was effectively filed before 2017-03-31.

2. Claim 1 element breakdown and prior-art mapping

Claim 1 is the sole independent claim, so it is the crux. Its elements and the mapping:

Bottom line on claim 1: elements A, D, E, and G are met essentially verbatim by Bashir (with Thales for the frame/arms geometry); the force-specific elements (B) are met by Delatorre/Shinko; element C is met by Bashir. The only element not squarely met by a single reference is F (the broadband pulse), which is a known technique.

3. The obviousness combinations

Combination 1 (primary): Bashir + Delatorre (optionally + Thales)

• Bashir supplies a micromachined, magnetically (Lorentz) driven, optically read resonant structure with a conductor on the suspended members, permanent magnets, and a function-generator/lock-in control loop. Bashir measures a mass-induced resonance shift.
• Delatorre (and/or Shinko) supplies the missing teaching that the same kind of resonant element's frequency shifts with an applied load/force, and that force magnitude is thereby measured.
• Thales supplies, if needed, the specific frame/arms/anchoring geometry and capacitive read-out for a micromachined vibrating structure.

Why a POSITA would combine (KSR rationales):

1. Same field, same problem. All three address micromachined/mechanical vibrating-element transducers; Delatorre and Shinko are literally "load-sensitive resonator" and "force converting mechanism" patents in the same class (G01L force measurement), and the patent itself is classified under G01L1/10 (force by frequency variation of vibrating elements). A POSITA looking for a high-sensitivity force sensor would naturally start from the resonant-element force art (Delatorre/Shinko) and from the MEMS resonant-sensor art (Bashir).
2. Predictable result / established function. Substituting a force/strain input for a mass input at the input of the same resonance-shift read-out is a predictable use of the reference elements according to their established functions (KSR). The physics — an applied load alters stiffness/tension and thus shifts a resonant frequency — is the very thing Delatorre/Shinko teach and the very thing the patent's own background and "core of the invention" restate.
3. Design incentive to miniaturize. The patent's own background states small forces (<1 µN, down to pN) "cannot be measured using strain gauges," and the specification says MEMS dimensioning enables nN/pN sensitivity. Bashir and Thales are the references that teach how to build such a microscale silicon rigid-body/flexure structure (SOI). That supplies a strong motivation to combine.
4. Magnetic drive was a recognized, off-the-shelf option. Lorentz-force actuation of a micromachined resonator (a current-carrying conductive member in a magnetic field) was a known technique, as confirmed by the very "similar documents" on this patent's page — e.g., US9671471B2 ("Magnetic sensor including a Lorentz force transducer…"), US9417097B2 ("Device for measuring magnetic fields with Laplace force"), and JP4604037B2 ("Resonant magnetometer device"). Using a known technique (Lorentz drive) to improve a similar device (a resonant force transducer) supports obviousness.

Result: Claim 1 is rendered obvious by Bashir in view of Delatorre (and Thales for structure) — with element F handled as a known technique (below).

Combination 2 (alternate lead): Delatorre/Shinko + Bashir

Lead with the force-to-frequency references (Delatorre, Shinko) as teaching the invention's core idea, and use Bashir as the MEMS/Lorentz/optical implementation. This is the mirror image of Combination 1 and reaches the same result; it is the framing most favorable to a challenger because it starts from the exact problem the patent addresses (force measurement) rather than a mass sensor.

Combination 3 (for dependent claim 26 — prosthesis): Combination 1/2 + Orthosensor

US20170252187A1 (Orthosensor) discloses sensors placed in prosthetic components (e.g., a tibial insert/prosthetic joint) to monitor loading, force/pressure, and alignment in the muscular-skeletal system. The patent's own specification states the force sensor is "particularly suitable for… prosthetics" and that prostheses/implants may be "equip[ped]… with force sensors according to the invention." Motivating combination: placing the claimed sensor in a prosthetic component is the predictable use of a force sensor in the known application environment taught by Orthosensor (KSR; MPEP 2144.04, analogous intended use). Claim 26 is therefore obvious over Combination 1/2 + Orthosensor.

4. Dependent claims (2–25)

Because every dependent claim adds only conventional structure or a conventional use of the same art, they fall with claim 1:

• Claims 2–5 (suspension regions at corners; four corners; rectangle/square): routine design choice in a micromachined frame; Thales' orthogonal arms/anchors and Bashir's rectangular/square platforms make these obvious.
• Claims 6–7 (meander-shaped frame section between suspension regions): compliant/meandering flexures to lower stiffness (increase sensitivity) are ubiquitous in MEMS; Thales uses flexure arms/decoupling members, and Delatorre expressly addresses length-mismatch compensation members. Obvious design choice to tune sensitivity (the patent itself frames the meander as "similar to a helical spring," a known expedient).
• Claims 8–9 (arms = multiple of four; exactly four): obvious structural choice; Delatorre's double-beam/tuning-fork and Thales' symmetric two-mass structures make symmetric multi-arm arrangements conventional.
• Claims 10–18 (coupling element; polygonal/four-cornered/rectangular/square; arms fixed at corner points/one end): conventional coupling-frame geometry, directly paralleled by Thales' coupling structure (20,20′,22) linking vibrating assemblies.
• Claim 19 (meander-shaped temperature-compensation structures): Delatorre explicitly addresses temperature-induced frequency error with a moment-decoupling member; temperature compensation of resonators is a known practice. Obvious.
• Claims 20–21 (one-piece silicon, mono-crystalline; SOI): Thales and Bashir both use SOI/mono-crystalline silicon fabrication. Squarely met/obvious.
• Claim 22 (≥2 conducting means driven counter-phase): Thales uses phase-opposition drive of symmetric masses, and differential/counter-phase drive is standard in resonant MEMS. Obvious.
• Claim 23 (sequential multi-mode pulses): exciting different resonant modes in sequence is a known measurement technique (and is taught in the frequency-domain instrumentation art). Obvious.
• Claim 24 (permanent magnet and/or Helmholtz coil): Bashir expressly uses permanent magnets; Helmholtz coils for defined fields are conventional. Obvious.
• Claim 25 (excite in-plane oscillations): Thales drives in-plane motion (Ox/Oy) and detects in-plane; in-plane modes are inherent to the geometry. Obvious.
• Claim 26 (prosthesis): addressed in Combination 3.

5. Anticipated patentee rebuttals and my assessment

A patentee would likely argue:

1. "Bashir is a mass sensor; force is not mass." Rebuttal: Delatorre/Shinko close exactly that gap, and the patent's own background/spec admit the shared principle (resonance-frequency shift as the measurand) and the MEMS miniaturization goal. The substitution is the predictable use of the reference elements.
2. "None of the references teaches a frame whose suspension regions move relative to each other to strain the oscillator." Rebuttal: Thales' suspended frame/mass with compliant arms anchored at fixed regions discloses relative displacement of anchored regions under a load; and Delatorre's whole point is that relative end displacement (strain) shifts the resonance. A POSITA would recognize the kinematic equivalence.
3. "The broadband AC pulse (element F) is absent." This is the strongest patentee point. Bashir's figure shows a function generator (a swept or fixed drive) with lock-in detection, arguably a single-frequency drive rather than a bandwidth-comprising pulse. Challenger's counter: the specification itself frames the pulse as a time-saving optimization over sequential single-frequency application, and broadband/chirp excitation was a well-known alternative for rapidly locating a resonance — i.e., a "known technique to improve a similar device" (KSR). This element is where a §103 challenge is most vulnerable and where the patentee has the best footing; a fact-finder could go either way, but the weight of KSR case law favors obviousness for a mere speed optimization using a known excitation technique.
4. Secondary considerations (Graham factor 4). I found no evidence of nexus-backed commercial success, licensing, copying, or industry praise tied to the claims; nor did my earlier search locate assertion/litigation that might have generated such a record. Absent such evidence, the objective indicia do not rebut the prima facie case.

Element-by-element strength summary:

6. Conclusion

• Claim 1 is likely obvious under §103 over Bashir (WO2011163058A2 / US20140026686A1 / US9250113B2) in view of Delatorre (US5095763A), optionally with Thales (US20080210005A1) for the frame/arms geometry — the references collectively teach every element, and KSR supplies the motivation (same field/problem, predictable substitution of a force input for a mass input at a resonance-shift read-out, known Lorentz-drive technique, and an admitted miniaturization goal).
• Alternate formulation with equal or greater force: Delatorre/Shinko + Bashir (lead with the force-to-frequency references).
• Element F (broadband pulse) is the only element requiring the "known technique to improve a similar device" rationale; it is the single point at which a patentee has a genuine, non-frivolous non-obviousness argument.
• Dependent claims 2–25 add only conventional geometry, materials, temperature compensation, drive modes, or read-out options that are individually disclosed or obvious over the same references.
• Claim 26 (prosthesis) is obvious over the above combination further in view of Orthosensor US20170252187A1, which teaches force/load sensors in prosthetic components.

Caveats. (1) I could not complete verification searches for US9671471B2, JP4604037B2, and US9417097B2 before hitting a tool limit; I cite them only as corroborating the general knowledge that Lorentz/Laplace-force actuation and resonant magnetometry were known, and they appear on this patent's "similar documents" list rather than as prior art of record. (2) The Bashir family's exact disclosure of broadband/pulse excitation was not fully confirmed; element F rests on the swept-drive disclosure plus the "known technique" rationale. (3) This is an analyst's invalidity opinion, not a legal conclusion; claim construction of "conducting means"/"read-out means" (whether treated as means-plus-function under §112(f)) could shift the analysis. (4) As noted, the patent is expired for fee non-payment, so this analysis is of historical/academic interest unless the patent is revived.