US 8299550

I'll search for authoritative information on US patent 8299550, including any 2026 CAFC activity.

Let me run a few more targeted searches to check for any litigation or CAFC activity.

US 8,299,550 B2 — Search Summary

CAFC 2026 docket check — result: nothing found

I ran targeted searches for any Court of Appeals for the Federal Circuit activity in 2026 tied to patent 8,299,550. I found no CAFC 2026 docket, appeal, or decision involving US 8,299,550, and no district-court litigation asserting it. Because patent numbers are easily conflated, note that my searches did surface several unrelated matters with similar-looking identifiers — e.g., US 9,321,386 / US 9,975,750 (Vermeer v. Kubota), US 8,511,550 (Loyalty Conversion Systems CBM, airlines), US 8,955,869 / US 9,403,550 (juvenile-products IPRs), and headline 2026 Federal Circuit appeals such as Contour IP Holding LLC v. GoPro, Inc. (No. 2026-2012) — none of which involve 8299550. Treat "no 2026 CAFC activity" as my best-supported conclusion rather than a certified negative; I cannot exhaustively query PACER/CM-ECF from here, and a formal docket pull would be the definitive check.

Bibliographic data (authoritative from the granted patent)

Abstract (verbatim)

When the initial displacement greatly varies among cells in an element, there is a need to reduce a bias voltage to be applied between electrodes. This decreases the sensitivity. An electromechanical transducer of the present invention includes an element having a plurality of cells. Each of the cells includes a first electrode and a second electrode that are provided with a cavity being disposed therebetween. A groove is provided at a position at a predetermined distance from the cavity of the cell on the outermost periphery of the element.

Technology in one paragraph

The patent is a capacitive micromachined ultrasonic transducer (CMUT). A transducer "element" is an array of many small cells, each cell being a parallel-plate capacitor: a lower electrode, a cavity, and a flexible vibrating membrane carrying (or serving as) an upper electrode. The problem addressed is that the membrane's initial displacement (resting deflection from internal stress plus ~1 atm pressure differential) is larger for the outermost cells than for interior cells. Because pull-in voltage depends on initial displacement, that spread limits the usable DC bias and therefore sensitivity. The disclosed fix is to etch a groove or localized recess into the thin film / support region around the outer periphery of the element (optionally around each cell), which equalizes the mechanical boundary conditions — joint area and internal-stress distribution — between edge cells and center cells. The specification quantifies the benefit by finite-element analysis (ANSYS 11.0, 11×11 cell model): groove depth, width, and cavity-to-groove spacing are all analyzed, with a preferred cavity-to-groove distance of 50–200% of the inter-cavity distance (more preferably ≤100%).

Independent claims — plain language

Claim 1 — The base apparatus claim. An electromechanical transducer has an element made of multiple cells; each cell has a first electrode and a second electrode with a cavity between them, plus a vibrating film that deflects when voltage is applied across the electrodes. A groove is placed at a predetermined distance from the cavity of the element's outermost cell, and it is positioned/configured so that, on actuation, the difference in displacement between the outermost cell and an innermost cell is less than it would be without the groove. (The "less than … when the groove is not provided" language is a functional result limitation that appears to have been added to secure allowance.)

Claim 7 — A second, "thinning" variant of the same idea, drafted from the film's structure rather than from a groove: an element of multiple cells, each with a first electrode, a thin film disposed with a cavity between it and the first electrode, and a second electrode in the thin film. The portion of the thin film at a predetermined distance from the outermost cell's cavity is made thinner (or removed), and the claim's functional limitation is that the outer-to-inner cell displacement is less than it would be if that portion were not thinned. Note this claim's language as printed is grammatically awkward (it refers to "a displacement amount" between outer and inner cells "less than the displacement amount when the portion … is not thinner"); I'd flag it as a drafting artifact rather than read it as a distinct structural requirement.

Claim 8 — A third independent claim keyed to groove size relative to the cavity: an element of multiple cells, each with first and second electrodes and a cavity between them, where a groove is located at a predetermined distance from the outermost cell's cavity and the groove's length exceeds the cavity's length in a direction parallel to the cell-array surface.

Dependent claim structure (for context):

• Claims 2–6 depend from claim 1: groove formed in the thin film (2); groove penetrating the thin film into the support portion (3); predetermined distance ≤ inter-cavity distance (4); groove also between cavities (5); groove continuously extending outside the outermost cell (6).
• Claims 9–13 mirror these for claim 8: groove in the vibrating thin film (9); penetrating into the support (10); distance ≤ inter-cavity distance (11); groove also between cavities (12); groove continuous on the outer side (13).

Caveats / uncertainty

• No litigation identified. I have high confidence there is no 2026 CAFC matter on this patent, but that is an absence-of-evidence finding from web search, not a PACER-certified negative.
• Assignee status: Canon Kabushiki Kaisha is the recorded assignee (assignment recorded July 27, 2010). I did not verify the current chain of title beyond that record.
• Maintenance-fee lapse: The patent lapsed effective Oct. 30, 2024 for nonpayment of the 12th-year fee (event code FP), with the 8th-year fee paid in April 2020. It remains listed as Expired – Fee Related. Any assertion of live rights would be inconsistent with the record; reinstitution would require petitionable relief not reflected here.

I'll search for litigation involving US patent 8299550 across patent litigation databases.

The first search returned an unrelated result. Let me refine my search.

None of those results reference litigation involving this exact patent. Let me search more targeted litigation databases.

Litigation Search Results: US Patent 8,299,550

Bottom line

I found no evidence of any litigation involving US Patent 8,299,550 ("Electromechanical transducer," Canon K.K.). Based on the searches I was able to run against patent-litigation-oriented sources, this patent does not appear in any district court, ITC, or Federal Circuit case.

What I searched and what came back

Important caveat on search coverage

I was operating under a tool-call limit and was not able to complete direct queries against the specific databases you named (Unified Patents litigation portal, PACER, CAFC docket search) — the queries I attempted against those returned no matching records, but my coverage was not exhaustive. So my negative finding should be treated as "no litigation found in the sources I was able to reach," not as a certified all-database confirmation.

Context that bears on the "no litigation" conclusion

The absence of litigation is consistent with the patent's public record on Google Patents:

• Assignee: Canon Inc. (large, operating company — not an NPE/assertion entity)
• Prosecution/priority family: JP 2009-096145 (filed 2009-04-10); US 12/753,782 filed 2010-04-02; granted 2012-10-30
• Family members: continuation US 13/610,144 (abandoned, pub. US2013/0000116A1) and continuation US 14/445,945 (granted as US 9,180,489)
• Status: Expired – Fee Related. Maintenance fees lapsed; the patent expired 2024-12-02 for nonpayment of maintenance fees under 37 CFR 1.362 (effective 2024-10-30).
• Cited-by list: The forward citations shown are other Canon applications/patents (e.g., US2012/0112603, US 9,073,085, US 9,180,489), Kolo Technologies CMUT documents, Samsung, and Seiko Epson — these are citations, not litigation.
• PTAB: No IPR/PGR/CBM naming US 8,299,550 appears in the search results. (Note: Patents-viewer results that mention "IPR" here relate to Unrelated patents such as US 7,792,256, US 10,311,073, US 9,253,239.)

Recommended next steps to confirm definitively

Since I could not fully exhaust the docket-level sources, I recommend these specific checks:

1. Unified Patents Litigation portal – https://portal.unifiedpatents.com/litigation (search the patent number directly)
2. Docket Alarm / Docket Navigator – search 8,299,550 as an asserted patent
3. PACER – search the patent number across district courts
4. CAFC – search the patent number in the Federal Circuit docket
5. USPTO PTAB (Patent Trial and Appeal Board) – confirm no IPR/PGR/CBM
6. USPTO Assignment/Reassignment records for the '550 and the '489 continuation (could reveal a sale/assignment to an assertion entity, which is a common precursor to litigation)

Requested table

If you need, I can re-run the specific Unified Patents and PACER/CAFC queries in a follow-up so the negative finding is documented against each of those sources individually.

I'll verify the structured-data default against live sources before drafting.

Let me probe a few more angles to be thorough before concluding the default holds.

One final confirmation pass with different phrasings:

Proceedings overview

Zero AIA trial proceedings are on file against US 8,299,550. The structured USPTO Open Data Portal block returns no IPR, PGR, or CBM for this patent, and repeated targeted web searches surfaced no PTAB proceeding naming US 8,299,550 — the only hits were false positives on different patents that happen to end in "550" (e.g., U.S. 8,673,550 in IPR2015-00057; U.S. 9,403,550 in the Evenflo/Evenflo-related petitions; a Chinese-priority "550 Patent" in IPR2016-01707). Bottom line for a defendant: the patent was never tested at the Board, all 13 claims are UNTESTED, and there is no claim-cancellation shield to hand you — but the more consequential fact is administrative: the patent expired for failure to pay the 11.5-year maintenance fee, effective 2024-10-30 (lapse recorded 2024-12-02), so the live question is not PTAB exposure but whether any enforceable term remains.

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No proceedings to itemize

There is nothing to put in the per-proceeding template — no proceeding number, petitioner, panel, institution decision, or FWD exists for US 8,299,550. I will not populate that template with invented data.

One clarification worth recording so nobody on your team repeats the error: search engines readily conflate this patent with other "…550" patents that have been through the Board. Those are unrelated:

None of these cite or involve Canon's US 8,299,550.

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Strategic summary

Claim status: All of claims 1–13 are UNTESTED — no FWD, no reissue, no reexamination, no disclaimer of record visible in the structured data. Independent claims are 1 (groove at a predetermined distance from the outermost cell's cavity, expressed functionally by reduced displacement variation), 7 (same concept claimed as a thinner thin-film region), and 8 (same, with the groove longer than the cavity in the plane). Claims 2–6 depend from 1; 9–13 depend from 8. Because nothing was canceled, there is no carve-out, no narrowing amendment, and therefore no § 315(e)(2) estoppel attached to anyone — no petitioner exists, so no prior-art ground has been "used up."

Estoppel landscape: With no IPR/PGR, there is no statutory estoppel against any party. A defendant retains the full universe of § 102/§ 103/§ 112 grounds in district court, and would retain the ability to file its own IPR — except that the practical value has collapsed: under § 315(b) the one-year clock only starts on service of a complaint, and an expired patent cannot be infringed going forward, so the only residual stake is past damages within the § 286 six-year lookback for conduct during the pre-2024-10-30 term.

Pattern signals: None to report. Canon (the original and current assignee) never had to defend this patent at the PTAB. There is no serial-petitioner pattern, no defensive aggregator (no Unified Patents, no RPX) in the chain for this patent, and no Federal Circuit appeal — the continuation US 9,180,489 also lapsed for fee non-payment. The nearest family members (US 8,455,964 / US 9,276,501, the "dummy cell" line) are separate patents and were not part of any proceeding here.

The real defensive card is expiry, not estoppel. Per the legal-events record, the 11.5-year maintenance fee went unpaid; the grace period closed 2024-10-30 and the patent is recorded as expired on 2024-12-02 ("PATENT EXPIRED FOR FAILURE TO PAY MAINTENANCE FEES UNDER 37 CFR 1.362"). Google Patents still displays an "Adjusted expiration 2030-12-06" figure — that is the nominal PTA-extended term, not a statement of enforceability; the fee lapse controls.

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Recommended next steps

• Do not over-invest in a PTAB defense. There is no proceeding to distinguish, no FWD to leverage, and no estoppel to argue. Confirm the absence yourself at the USPTO's Open Data Portal (https://data.uspto.gov/) and PTAB E2E (https://ptacts.uspto.gov/ptabweb/) before finalizing any invalidity budget.
• Pull the maintenance-fee and status record first. The highest-value verification is the fee-lapse entry and its effective date (2024-10-30). If confirmed, any current demand letter must be assessed for whether it is asserting an expired patent — a demand premised on ongoing infringement of a lapsed patent is a strong candidate for a Rule 11 / § 285 posture letter.
• Scope any remaining exposure to the damages window. Unexpired-term conduct before 2024-10-30 within § 286's six-year lookback is the outer boundary. Build your date-of-first-infringement record accordingly.
• Keep invalidity in reserve, not in the lead. If some residual past-damages theory is pressed, the § 102/§ 103/§ 112 record is untouched by any prior PTAB adjudication, so you can attack freely — but expect the plaintiff's own case to be constrained by the patent's expiration rather than by claim scope. Note for completeness that an expired patent can still be the subject of an IPR (claims construed under Phillips), so an IPR remains technically available if a damages theory materializes; it is simply unlikely to be cost-justified.
• If a PTAB filing does appear after this analysis (a late-served complaint plus a defensive petition), the statutory roadmap is: PO preliminary response, institution decision at ~6 months, then a hard 1-year trial clock to FWD from institution (§ 316(a)(11)). Nothing in that pipeline exists today.

Primary sources for verification: Google Patents record for US 8,299,550 (https://patents.google.com/patent/US8299550/en), including its Legal Events table; USPTO Open Data Portal (https://data.uspto.gov/); PTAB E2E (https://ptacts.uspto.gov/ptabweb/); CourtListener for any CAFC activity (https://www.courtlistener.com/). I found no CAFC docket for this patent, and the JP counterpart JP5436013B2 is likewise unrelated to any Board proceeding.

I'll research the assignment record for US 8,299,550 across the sources you specified.

Let me dig into the assignment-specific sources and the continuation patents.

Coverage note (read first)

You asked me to work primarily from USPTO Assignment Center (assignmentcenter.uspto.gov / assignment.uspto.gov). I was unable to complete direct, live queries against those endpoints — the searches I ran returned no Assignment Center records and I hit a tool-call ceiling before exhausting the substitutes. The reel/frame data below therefore comes from the Google Patents "Legal Events" assignment abstract, which mirrors the same USPTO assignment-record data, plus the patent's own front-page/Justia bibliography. Treat the single-absent-assignment finding as reliable but not docket-exhaustive; the specific checks worth re-running yourself are listed at the end.

This builds on the earlier litigation search, which found no litigation naming US 8,299,550. Nothing in the assignment record contradicts that; the two findings reinforce each other.

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Inventors

Pattern check: There is no unusual departure pattern. Both inventors executed their assignment to Canon before the application was filed (signing dates 2010-03-24 to 2010-03-29; US filing 2010-04-02). That is the textbook employee-invention assignment, not the "all inventors left within 12 months" precursor to a portfolio fire-sale. I could not independently verify either inventor's current employer or departure date from the sources available; no source surfaced suggesting either departed Canon in connection with this patent.

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Original assignee

Canon Kabushiki Kaisha (Canon Inc.), 30-2 Shimomaruko 3-chome, Ohta-ku, Tokyo 146-8501, Japan.

• Entity type / business: Large operating company — imaging, optical, medical-imaging and semiconductor equipment. The '550 patent sits in Canon's CMUT (capacitive micromachined ultrasonic transducer) R&D line, the same program that produced the cited-by Canon family (US 2012/0112603, US 9,073,085) and the continuation-in-family US 9,180,489.
• Product embodying the claims: The specification's stated application is CMUT ultrasound elements for transmit/receive arrays. Canon does commercialize ultrasound/medical-imaging hardware (Canon Medical Systems), so an operating-company embodiment pathway exists. I did not find a publicly documented shipping product specifically reading on the '550 claims, so I flag that as unconfirmed rather than asserted.
• Current status: Operating. No bankruptcy, no dissolution, no acquisition. Current assignee of record is still Canon.

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Assignment timeline

Only one assignment is recorded for US 8,299,550. There is no post-issuance assignment chain.

• 2010-03-24 to 2010-03-29 (executed) / recorded 2010-07-27 — Reel 024743/0557
  • Conveyance: Assignment (recorded as "ASSIGNMENT OF ASSIGNORS INTEREST")
  • Assignor: Zaitsu, Yoshitaka; Kawasaki, Takehiko
  • Assignee: Canon Kabushiki Kaisha (Japan)
  • Correspondent of record: Not retrievable from the sources available to me. Flagged as unclear, not as absent — Canon's prosecution correspondent is "Canon USA Inc IP Division" (per the Justia bibliography), but that is the prosecuting attorney, not the assignment-recording correspondent you asked me to capture. I will not substitute one for the other.
  • Context: Inventor-to-employer assignment, executed pre-filing. Ordinary, expected, non-NPE.

Non-assignment legal events for context (not transfers):

• 2010-04-02 — US application 12/753,782 filed by Canon.
• 2012-10-30 — Patent granted (US 8,299,550 B2).
• 2016-04-13 / 2020-04-16 — Maintenance fees paid (4th, 8th year).
• 2024-06-17 — Maintenance-fee reminder mailed.
• 2024-12-02 — Patent expired for failure to pay maintenance fees (effective 2024-10-30) under 37 CFR 1.362.

Family-wide check: The JP priority filing (JP 2009-096145 → JP 5436013B2 / JP 2010251847A) and the two US continuations (US 13/610,144, abandoned, pub. US 2013/0000116A1; and US 14/445,945, granted as US 9,180,489) all list Canon as assignee. No intra-family reassignment to a third party appears anywhere in the family. I did not have direct reel/frame data for the continuations, so I cannot rule out a recorded assignment there that Google Patents did not surface — but nothing suggests one.

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Timeline diagram

timeline
    title Ownership of US 8299550
    2009 : JP priority application filed
    2010 : US application filed
         : Inventors assign to Canon
    2012 : Patent issued to Canon
    2020 : Eighth year maintenance fee paid
    2024 : Expired for unpaid maintenance fee

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NPE / troll-pattern signals

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Verdict

Insufficient data (only the original assignment).

Under your taxonomy this is the designated bucket for "no records, or only the original assignment," which is exactly what the record shows: a single inventor-to-employer assignment, executed 2010-03-24 to 2010-03-29 and recorded 2010-07-27 at Reel 024743/0557, from Zaitsu and Kawasaki to Canon Kabushiki Kaisha — with no subsequent assignment of any kind. To be explicit, "insufficient data" here is not an inability to characterize NPE risk: on the available record the NPE signal count is zero of eight, and the patent is a Canon operating-company asset that lapsed for non-payment of maintenance fees on 2024-12-02. If you want a positive characterization rather than the literal taxonomy bucket, the accurate description is operating-company-held, never-asserted, expired.

Verification link: https://assignmentcenter.uspto.gov/ — search 8299550 (or application 12/753,782) to confirm the single-entry result and, critically, to capture the assignment correspondent at Reel 024743/0557, which my available sources did not expose.

Suggested re-runs to close the gaps I could not: (1) Assignment Center by patent number, to capture the Reel 024743/0557 correspondent name/firm; (2) Assignment Center by assignor name "Zaitsu" and "Kawasaki" for any later personal-holdings assignments; (3) the same for the continuations US 13/610,144 and US 14/445,945 / US 9,180,489 to confirm the family had no post-issuance transfers; (4) RPX and Unified Patents asserter directories by patent number and by assignee string "Canon Kabushiki Kaisha," to confirm no assignment-based asserter association.

I'll research the specific prior-art references cited on the face of US 8,299,550. Let me pull authoritative details on the most relevant ones.

Let me pull details on the remaining cited references.

Prior-Art Analysis — US 8,299,550 B2 ("Electromechanical transducer," Canon K.K.)

0. Identification confirmed (strict-number discipline)

I anchored everything to the granted patent record at https://patents.google.com/patent/US8299550/en (which mirrors the USPTO full-text and image records) and to the individual reference records. I did not substitute any similar-looking number. In particular, I explicitly note that search hits for US 9,403,550 (juvenile-products IPRs), US 8,511,550 (Loyalty Conversion Systems), and US 9,321,386 / US 9,975,750 are different patents and were discarded.

This is a CMUT patent. The inventive contribution is the placement of a groove/recess at the outer periphery of the element, which equalizes the membrane's internal-stress boundary conditions so that the outermost cell's initial displacement matches that of the interior ("innermost") cells — enlarging the usable bias window before pull-in. Independent claim 1 carries the critical functional limitation ("a displacement amount difference … is less than … when the groove is not provided"); claim 7 is the "thinned-film" variant; claim 8 keys on groove length > cavity length.

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1. The 13 references cited on the face of US 8,299,550

The Google/USPTO front page lists 13 patent citations. I reproduce each with full citation, dates, a description, and the § 102 assessment. A * marks Examiner citations; unstarred entries were IDS/third-party citations.

A. The three "legacy transducer" citations (background-only)

These three are the kind of boilerplate "transducer" references Examiners pull to support the term-of-art in the preamble. None is anticipatory under any subsection of § 102.

B. The core CMUT references

C. The Canon co-pending applications (largely background/related art)

Dates caveat / possible contradiction flag: refs 11–13 (and, marginally, 9–10) are same-assignee Canon filings. Under pre-AIA § 102(e) a published application is art only as of its US filing date and only if "by another." Because refs 11–13 were filed after the '550's 2009-04-10 priority date, they cannot be § 102(a)/(b)/(e) art no matter who the inventor is. If any tool or database labels these as "prior art anticipating 8,299,550," that label is wrong and should be rejected.

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2. Additional "family" citations (JP family of the '550)

The Google Patents "Family Cites Families" list contains six Japanese references cited in the family (notably in the JP counterpart JP 5436013 B2). They are citation-of-record in the family, not on the US front page, and I list them for completeness:

None of these discloses the '550's defining combination (outer-periphery groove positioned to equalize cell displacement and reduce outermost-vs-center variation). They are background/§ 103 material.

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3. Bottom-line answer to the question asked

No reference cited on or in the US 8,299,550 record anticipates any claim under 35 U.S.C. § 102.

• Claims 1 and 7 are distinguishable by their express functional/result limitations (outermost-cell displacement difference "less than … when the groove is not provided" / "less than … when the portion … is not thinner"). No cited reference discloses, let alone inherently performs, that equalization effect. The functional language is precisely what appears to have carried the case to allowance over the CMUT art (refs 4, 5, 7, 8).
• Claim 8 adds a purely spatial limitation — groove length > cavity length measured parallel to the cell-array plane — that is likewise absent from every cited reference (Olympus's trenches in refs 5 and 7 run between elements, not around an outermost cell's cavity).
• The three legacy references (US 3,259,124; US 3,334,623; US 4,096,047) are non-analogous and cannot anticipate.
• The Canon co-pending applications (refs 9–13) are same-assignee background; refs 11–13 are filed after the 2009-04-10 critical date and are therefore legally incapable of being § 102 art against the '550.

Most relevant prior art, ranked:

1. JP 2006-122188 A / US 2007/0299345 A1 (Olympus–Adachi, refs 5 & 7) — closest to the "groove" concept, but placed between elements for grounding/crosstalk (and, per the same spec, itself creates a standing-wave "noise component"). Distinct purpose and location from the '550's peripheral displacement-equalizing groove → best § 103 combination candidate, no § 102.
2. US 6,958,255 B2 (Stanford/Khuri-Yakub, ref. 4) — the base CMUT structure and the process the '550 builds on; supplies the preamble elements of claims 1/8 but nothing of the inventive groove → § 103 base, no § 102.
3. US 7,074,634 B2 (CNR/Foglietti, ref. 6) and US 7,512,038 B2 (Hitachi, ref. 8) — process/structure background on membrane stress and CMUT stack; no peripheral-groove teaching.
4. Canon co-pending applications (refs 9–13) — background; cite no more than the common CMUT platform.

Caveats I will not paper over: (i) I worked from the front-page citation list plus Google Patents/FreePatentsOnline/EPO full texts; I did not run a live, certified USPTO Patent Full-Text (PatFT/Patent Public Search) query, so "no other art of record" is my best-supported reading of the record, not a certified negative. (ii) For refs 9–10, whether they even qualify as § 102(e) art turns on the "by another" / common-ownership facts, which the public record does not fully resolve; I flagged rather than assumed it. If you want, I can re-run the citation list directly against USPTO Patent Public Search and the JP 5436013B2 file wrapper to confirm the JP-family citations as well.

I'll ground the obviousness analysis in the actual prior-art references cited on this patent's page. Let me characterize what those references disclose.

Good — the prior art is rich. Let me characterize the remaining cited references (Hitachi, Canon's earlier applications, and the family-cited Japanese art).

Obviousness Analysis — US 8,299,550 B2 under 35 U.S.C. § 103

Scope note. This analysis is confined to the "Patent Citations (13)" list — the Prior Art section of the patent's own Google Patents page (https://patents.google.com/patent/US8299550/en) — plus one reference (U.S. Pat. No. 5,982,709) that is disclosed within one of those cited references and is therefore reachable through the cited-art record. I do not treat the "Cited By" list as prior art (those are later documents). Because the '550 application was filed April 2, 2010 with a April 10, 2009 JP priority, pre-AIA § 102/§ 103 govern (AIA §§ 102–103 apply only to applications filed on or after March 16, 2013), which matters for the § 102(e) and § 103(c) points below.

As established in the earlier-generated sections, the patent expired for fee non-payment effective 2024-10-30. This § 103 analysis is therefore a defensive/validity workup, not an infringement-positioning exercise.

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1. Legal framework applied

• Graham v. John Deere Co., 383 U.S. 1 (1966): scope/content of claims, differences from prior art, PHOSITA level, secondary considerations.
• KSR Int'l Co. v. Teleflex Inc., 550 U.S. 398 (2007): a combination is obvious where a PHOSITA would have had a reason to combine with a reasonable expectation of success; "obvious to try" applies where there is a finite number of identified, predictable solutions.
• MPEP 2144.01(a)/2144.01(d): combining a known technique to improve a similar device in the same way, and combining prior-art elements according to known methods to yield predictable results.
• In re Best / In re Schreiber: a product claim limitation that recites a result or an inherent property of a structure does not impart patentability where the structure itself is otherwise known or obvious. (§ 103(a) governs here; In re Best is § 102 case law but the inherent-result principle is applied to §§ 102 and 103 alike via MPEP 2112.01 and 2144.04.)
• In re Aller / In re Boesch: optimizing a result-effective variable by routine experimentation is obvious, absent a showing of criticality.

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2. The claims as construed for § 103

The most important construction point is that "groove" is broad. The specification (Description) expressly defines it to cover any of: (1) a recess in the membrane from its upper surface; (2) a recess through the membrane and the insulating/support layer; (3) a recess formed by the absence of membrane around the outermost cell; or (4) a recess in the upper surface of the support portion. Equivalently: "a portion of the membrane … is thinner than a portion … on the cavity, or is removed." That definition essentially collapses claim 1 (groove) and claim 7 (thinned region) into the same structural concept expressed twice.

Other constructions:

The claims are apparatus claims only; there are no method claims to fall back on.

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3. Person having ordinary skill in the art (POSHA/PHOSITA)

A B.S. in EE, ME, applied physics, or materials science plus ~2–4 years of MEMS design/fabrication experience with capacitive micromachined transducers (or an M.S./Ph.D. with 1–2 years), familiar with: wafer-bonded and sacrificial-release CMUT fabrication (SOI membranes, oxide walls, sealed cavities); thin-film residual stress, stress gradients, and thermal-expansion mismatch; and ultrasonic array/element design (bias voltage, pull-in, membrane boundary conditions). This is a mature, crowded, incremental art by 2009.

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4. The cited prior-art record (from the page's Prior Art section)

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5. Element-by-element mapping

Claim 1

Claim 8 (groove longer than cavity, in-plane)

Same mapping as claim 1, plus: the JP 2006-122188 groove is an elongated boundary line running along the element edge, and the US 2007/0299345 trench 156 likewise runs along the element — in both cases longer (in-plane) than any single hexagonal/square cell cavity. Claim 8's added limitation is therefore inherent in the cited groove.

Claim 7 (thinned / removed region of the thin film)

Because the '550's own definition of "groove" includes a merely thinned membrane region, claims 1 and 7 rise and fall together — they claim the same structure in different words.

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6. Grounds of rejection

Ground 1 — Claims 1, 2, 4, 6: obvious over US 6,958,255 in view of JP 2006-122188 A

• US 6,958,255 supplies every structural element of claim 1 except the groove, and supplies the reason the periphery matters: the membranes are edge-clamped, so peripheral cells sit in a mechanically different boundary condition from interior cells.
• JP 2006-122188 A supplies the groove, and places it exactly where claim 1 requires — between adjacent vibrator elements / at both ends of the element — and does so expressly to shape element-level performance.
• Motivation: (a) same field (cMUT element design/fabrication) and same class of problem (element-boundary structure affecting transducer behavior); (b) KSR known-technique rationale — using an element-perimeter groove, a known element-isolation/relief technique, to improve a known CMUT element in a predictable way; (c) reasonable expectation of success — the '550 specification itself concedes the root cause ("warping of the substrate due to the difference in coefficient of thermal expansion between the membrane and the insulating layer and internal stresses"), so a PHOSITA would expect a perimeter structural discontinuity to alter the peripheral cells' stress boundary condition and hence their resting deflection.
• Claim 2 (groove in the thin film) is met by the recess being formed in the membrane layer, which is one of the '550's own enumerated groove definitions and is the natural location of a shallow element-boundary groove; claim 4 (distance ≤ inter-cavity distance) is a bare obvious design range the specification itself presents without criticality ("more preferably, less than or equal to the inter-cavity distance"); claim 6 (continuous around the outside) is met by JP 2006-122188's continuous boundary groove.

Ground 2 — Claim 3: obvious over US 6,958,255 + JP 2006-122188 A + US 7,074,634 B2

Claim 3 requires the groove to penetrate the thin film into the support portion. JP 2006-122188's own dependent claims teach a groove whose bottom penetrates the silicon substrate and electrode pad — i.e., deeper-than-membrane penetration is disclosed in the same reference. Independently, the depth of the groove is a result-effective variable: the '550's FIG. 9A shows the displacement difference decreasing monotonically with groove depth, i.e., a smooth, no-criticality optimization axis (In re Aller/In re Boesch). And US 7,074,634 supplies the design rationale by teaching that membrane stress gradients are the problem to be eliminated — which drives a PHOSITA toward deeper relief features.

Ground 3 — Claim 5 (and 12): obvious over US 6,958,255 + JP 2006-122188 A in view of US 2007/0299345 A1

Claims 5/12 add the groove between the cavities (around each cell). US 2007/0299345 expressly discloses trenches and dummy cells surrounding an element's cells, and the '550 specification acknowledges this is an alternative placement, not a distinct invention ("the difference in initial displacement amount can be reduced as long as a groove is provided on an element basis … instead of being provided on a cell basis"). Mere duplication of parts / alternative positioning of the same feature is obvious (MPEP 2144.04(a)).

Ground 4 — Claim 7: obvious over US 6,958,255 + US 7,074,634 B2 (and JP 2006-122188 A)

US 6,958,255 teaches membrane thickness/spring-constant as a design parameter. US 7,074,634 teaches that membrane stress/stress gradients are the recognized defect and that grooves and channels patterned into the membrane stack are the known remedy (its own characterization of US 5,982,709). Thinning a membrane region at the element periphery is the same act as forming a shallow groove — indeed the '550 defines a groove to include it. If claim 1 is obvious, claim 7 is obvious.

Ground 5 — Claim 8: obvious over US 6,958,255 + JP 2006-122188 A

Claim 8's only added limitation — groove length > cavity length in the plane — is inherent in the cited boundary groove, which is an elongated line running along the element edge and must exceed the in-plane dimension of a single cell cavity. No separate teaching is needed; where the prior art inherently meets a limitation, the claim is anticipated/obvious as a matter of law (In re Best principle).

Ground 6 — Claims 8–13: alternative over US 6,958,255 + US 2007/0299345 A1

US 2007/0299345's trenches 156 at the element ends, running the length of the element and separated from the cells by dummy neighbors 155, likewise meet claim 8's in-plane length limitation and claims 9–13's dependents, for the same reasons.

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7. Why the functional limitation ("less than … when the groove is not provided") does not save the claims

This is the crux, because the file history strongly suggests allowance hinged on it:

1. It adds no structure. The claim already recites the groove and its location. The "less than" clause merely recites the result of that geometry. Under In re Best/In re Schreiber, reciting an inherent property or result of an otherwise-known or obvious structure does not confer patentability.
2. The result is inherent in any peripheral relief groove in an edge-clamped membrane array, given the admitted stress/warp mechanism. A PHOSITA would expect it, so it cannot be an unexpected result.
3. The '550's own data show smooth, monotonic, no-criticality behavior. FIGS. 9A–9C and 10A–10B report displacement-difference reduction as a continuous function of groove depth and width — decreasing monotonically — and FIG. 9C presents the 50–200% spacing range as a trade-off against support strength, not as a criticality. That converts the functional limitation's supporting data into an admission of routine optimization.
4. Even if one treats the clause as a requirement that the groove be sized/placed to achieve the reduction, the specification's own preferred ranges (depth ≥ membrane thickness; width ≥ 10% of inter-cavity distance; spacing 50–200%) are exactly the values a PHOSITA would find by the routine FEA the patent describes (ANSYS 11.0 on an 11×11 model) — i.e., obvious to try with a reasonable expectation of success under KSR.

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8. Secondary considerations — none identified in the record

I found no evidence of objective indicia to rebut the prima facie case: no unexpected results (the FEA shows predictable, monotonic trends), no teaching-away in any cited reference (if anything, US 7,074,634 teaches toward stress-relieving patterned grooves), no evidence of long-felt-but-unsolved need, failure of others, copying, licensing, or commercial-success nexus in the material available to me. Absence-of-evidence is not proof of absence, but nothing on the face of the record supports a nexus argument, and the prior sections established that the patent was never litigated or challenged at the PTAB (so no third-party validation record exists).

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9. Claim-by-claim conclusion

Bottom line. All three independent claims (1, 7, 8) and their dependents present a strong § 103 case on the patent's own cited art, principally US 6,958,255 + JP 2006-122188 A, with US 7,074,634 B2 supplying the stress-management motivation and US 2007/0299345 A1 supplying the cell-perimeter/dummy-cell variants. The '550's own Background is an admission of the problem and mechanism, and its own FEA is an admission of routine optimization. I would expect the functional "less than" limitation to be the only real battleground — and it is vulnerable under In re Best and KSR.

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10. Caveats and limitations of this analysis

1. I did not retrieve the file wrapper / prosecution history. My inference that allowance hinged on the functional "less than" language comes from the granted claim text (which reads as though the functional clause was added to overcome art), not from a verified Office Action. A PAIR/PatentCenter pull of the 2012 notices of allowance and any prior § 102/§ 103 rejections is the single highest-value next step — it would show exactly which references the examiner already applied and why the case was allowed.
2. § 103(c) risk on Canon's own cited applications. US 2009/0313809 A1 and US 2010/0123366 A1 are prior art only under pre-AIA § 102(e). If they were, at the time the '550 invention was made, commonly owned (Canon) with, or subject to an obligation of assignment to the same person as, the '550, then pre-AIA § 103(c) disqualifies them as prior art for § 103 purposes. I did not verify inventor overlap or ownership status, so I have deliberately not relied on these as primary references. Do not build a rejection on them without checking the assignment records.
3. US 2011/0018387 A1, US 2011/0115333 A1, US 2011/0140212 A1 (Canon) are not prior art to the '550 — their priority dates (2009-07-24 and later) postdate the '550's April 10, 2009 priority. They appear in the citation list but cannot support a § 103 rejection.
4. JP family-cited art unverified. I could not confirm the public-availability dates of JP 4504255 B2, JP 4523879 B2, JP 4804961 B2, JP 4271252 B2, or JP 5578836 B2. Treat them as cumulative until their publication dates are pulled.
5. Second-hand characterization of US 5,982,709. My statement that it discloses "patterns comprising grooves and intricate channels" is US 7,074,634's own description of it, which I verified; I did not independently read the '709. If the '709's grooves relate to defining membrane geometry rather than relieving stress, the motivation argument still stands through US 7,074,634's own express objects (reducing membrane residual stress and stress gradients), but the '709 quote should be sourced carefully.
6. US 7,512,038 B2 is a single reference I characterized from its own specification text and the related family; its exact teaching on perimeter structure is limited, so I used it only as cumulative cell/membrane architecture art, not as a primary reference.

Key source: Google Patents record for US 8,299,550 B2 — https://patents.google.com/patent/US8299550/en (Prior Art / "Patent Citations (13)" table, and the Legal Events table showing the 2024-12-02 fee lapse).