US 11402355

I'll search for this specific patent number and check for any litigation activity.

Let me check specifically for any litigation or court docket activity involving this patent.

US 11,402,355 B2 — Quick Reference

I searched for this exact number and for related litigation. Bottom line: I found no CAFC 2026 docket entry and no district-court litigation activity for US 11,402,355. Both targeted docket searches returned either nothing or unrelated hits. I cannot verify a CAFC docket exists for this patent; treat absence of litigation as "not found," not as confirmed non-existence.

Caveat on "CAFC 2026 dockets": I do not have a live, authoritative CAFC docket feed, and my searches did not surface any Federal Circuit case citing this patent. If a docket exists, it did not appear in these results.

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Bibliographic Data (per the authoritative patent text supplied)

Family / global status (Country Status block):

• US 11,402,355 B2 — Active
• EP 3543687 B1 — Active
• CN 110426457 A — Pending/active
• CA 3037736 A1 — Pending/active
• ES 2980991 T3 — Active
• GB 2572215 A — not active / withdrawn

Assignment history confirms the three named inventors assigned their interest to Short Brothers PLC. Note that Short Brothers PLC is commonly identified as a Bombardier-affiliated entity, but I have not independently verified corporate parentage from an authoritative registry in this session — flagging that as an inference, not a verified fact.

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Abstract (verbatim)

"Systems and methods for detecting a kiss bond in a composite component are provided. Using reflected ultrasound data representative of reflected ultrasound energy from the composite component, a first threshold amplitude value between 2% and 5% higher than a predetermined baseline noise amplitude value of expected material noise in the reflected ultrasound energy from the composite component, and a second threshold amplitude value higher than the first threshold amplitude value, one or more occurrences of an amplitude of the reflected ultrasound energy exceeding the threshold amplitude value and less than the second threshold amplitude value are identified. The kiss bond is detected in the composite component based on the identified one or more occurrences of the amplitude of the reflected ultrasound energy."

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Plain-Language Overview of the Independent Claims

Independent Claim 1 — System. Apparatus with (a) an ultrasonic transmitter aimed into the composite, (b) an ultrasonic receiver capturing the return signal, and (c) a processor plus non-transitory memory programmed to:

1. Take the reflected-ultrasound data together with two thresholds: a first threshold set 2%–5% above a baseline noise amplitude (measured from known-good material), and a second threshold higher than the first;
2. Identify amplitude "hits" that exceed the first threshold but stay below the second threshold — this band represents a candidate ("potential kiss bond instance"). Below the first threshold is ordinary material noise; above the second is a conventional disbond;
3. Compare the backwall echo (reflection from the far/rear surface) against a backwall echo threshold; and
4. Conclude a kiss bond exists based on both the in-band occurrences and the backwall echo being "not less than" the backwall echo threshold.

The engineering logic: a genuine kiss bond reflects a weak internal echo yet still passes most of the beam through to the backwall, so the backwall echo stays strong — unlike a true disbond, which would either over-bright the internal echo or kill the backwall echo.

Independent Claim 13 — Method. The same four-step algorithm recited as a method (using reflected-ultrasound data + the 2%–5% first threshold + higher second threshold; identifying the in-band occurrences representing a potential kiss bond instance; comparing the backwall echo to a threshold; determining the kiss bond based on the occurrences and the backwall echo being not less than the threshold). Functionally, claim 13 mirrors claim 1 in method form.

Dependent claims (1–12 and 13–22) add: non-zero depth determination via time-of-flight (claims 2, 14); depth determination (3, 15); one-dimensional length vs. a length threshold (4, 16); area determination (5, 17); area determination by grouping adjacent occurrences at substantially common depth (6, 18); area vs. an area threshold (7, 19); location determination (8, 20); backwall echo exceeding the threshold (9, 21); and a backwall echo threshold of 80% of a pristine component's backwall echo amplitude (10, 22). Claim 12 recites half-wave rectified data; claim 11 recites 5–10 MHz operation.

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Notes, Inconsistencies, and Uncertainties

1. Granted claim set differs from the published application. The application (US 2019/0293610 A1) recited three independent broad aspects — including a processor/memory-only system claim and a dependent claim requiring a pre-check that the component is "free from disbonds." The granted 22-claim set contains only the transmitter+receiver system claim (1) and the method claim (13). The disbond pre-check and the processor-only system aspect do not appear in the granted claims as listed. I interpret this literally from the granted text and do not assert why (cancelled vs. amended) beyond noting the difference.

2. Literal drafting quirks in the granted claims. Claim 14 (method) recites "wherein the computer-readable instructions are further executable for…" — instruction language inside a method claim. Claim 21 likewise includes a duplicated "based on the comparing comprises determining…" construction. Per the operating rules, I am reporting these as literally written and not "correcting" them; they appear to be carry-over drafting artifacts.

3. Terminology. Claim 1's receiver element recites receiving "ultrasound energy from the composite component," while the surrounding language refers to "reflected ultrasound energy." Also, claim 1 says "the threshold amplitude value," referring back to the first threshold. These are read literally.

4. Prior art cited (21 patent refs / 16 NPL). Representative citations include WO 2012/125837 A1 (Purdue Research Foundation, "Weak bond detection"); US 2010/0031750 A1 (Roger Spencer, "UT method of identifying a stuck joint"); US 2018/0106765 A1 (The Aerospace Corporation); US 2005/0043930 A1 (Boeing, incompletely cured adhesive); EP 3296728 A1 (Mitsubishi Heavy Industries); and US 2017/0370885 A1 (Wyle Laboratories). Key non-patent citations include Poveromo et al., "Analysis of 'KISS' Bonds Between Composite Laminates" (2014) and Wood et al., "Ultrasonic Evaluation of Artificial Kissing Bonds in CFRP Composites" (2014). A UK Search Report dated 2018-05-18 (GB1804675.5) is cited.

5. Later citing documents of possible interest (per the "Families Citing" list): US 11,346,816 B2 (The Boeing Company — "Apparatuses, systems, and methods for detecting kissing bonds in bonded joints," 2022) and CN 113391302 B (dynamic double-threshold echo detection, 2023), plus the Verifi Technologies / Baylor University family on real-time ultrasonic defect visualization.

6. No verified information on CAFC appeal, IPR, or enforcement. I did not find any such activity and have no authoritative source for it. I would need a direct PACER, Docket Alarm, or CAFC docket query to confirm; I am explicitly stating I do not have high confidence on litigation status.

Sources: the supplied authoritative full text (https://patents.google.com/patent/US11402355/en), corroborated by https://patents.justia.com/patent/[11402355](/patent/11402355) and the pre-grant publication https://patents.google.com/patent/US20190293610A1/en.

I'll search for litigation involving US patent 11402355.

Let me refine my search with more specific terms.

Let me check specific litigation databases and verify the Short Brothers case.

Litigation Search Report — U.S. Patent No. 11,402,355

Patent identified: U.S. Patent No. 11,402,355 (US11402355B2), titled "Detection of kiss bonds within composite components." Application No. 16/362,341; filed March 22, 2019; granted August 2, 2022; priority to GB1804675.5 (filed March 23, 2018); assignee Short Brothers PLC; inventors William Christopher Campbell, Thomas Eoin O'Hare, and Samuel Colin Hanna. Adjusted expiration listed as July 1, 2040; status listed as Active. Google Patents lists no litigation (no "Litigation" events in the legal events section).

Findings

No litigation involving U.S. Patent No. 11,402,355 was found.

I searched for the exact patent number (11,402,355 / US11402355B2) across general web sources, patent aggregators, and litigation-oriented content (including CourtListener/Justia dockets surfaced in results, PACER-derived materials, and the CAFC opinion pages). None of the results identified any case asserting, challenging, or otherwise involving this specific patent.

To be specific about what the searches did and did not return:

1. No district court complaints or dockets naming US 11,402,355 as an asserted patent (or as a patent at issue in a declaratory judgment action) were located.
2. No PTAB proceedings (IPR, PGR, CBM, or derivation) directed to this patent were located. The PTAB-related document hits returned by the search were unrelated patents (e.g., a petition referencing RE43,023 and other unrelated matters).
3. No ITC Section 337 investigations referencing this patent were located.
4. No CAFC appeals referencing this patent were located.

One Potentially Related Case — Not Confirmed as a Patent Suit (Flagged, Not Asserted)

A search surfaced a Northern Ireland Court of Appeal decision caption: Short Brothers PLC v AAR Corporation, Court of Appeal in Northern Ireland, 4 April 2025, citation [2025] NICA 18, indexed via AustLII.

I want to be explicit about the limitations here: I could not confirm the subject matter of this case, and I did not obtain a PACER/CourtListener record or any filing that ties it to U.S. Patent No. 11,402,355. Based on the citation format (a Court of Appeal in Northern Ireland citation) and the fact that it appears in a non-U.S. jurisdiction, this is most likely a commercial/contractual or other non-U.S.-patent dispute rather than an infringement action on the '355 patent. I cannot confirm that it involves the patent at issue, and I should not be understood as asserting a connection. If this matter is relevant, it would require independent verification of the pleadings and the cause(s) of action.

Caveats on Search Reliability

• I could not access the Unified Patents litigation portal, Docket Navigator, or PACER directly; results are based on web-indexed coverage of those sources. Litigation that is recent, sealed, or not indexed may therefore be missed.
• Absence of results in the sources searched is not proof that no litigation exists; however, the complete absence of any docket, complaint, or news reference to this specific patent number across the searches performed is consistent with the patent never having been litigated.

Bottom Line

Based on the searches performed, there is no known litigation involving U.S. Patent No. 11,402,355. The patent is a 2022 grant to Short Brothers PLC in a narrow technical area (ultrasonic kiss-bond detection in composites), and no assertion, validity challenge, or other proceeding against it appears in the public record sources searched. If you need a definitive negative, I would recommend a paid Docket Navigator or Lex Machina patent-specific query, or a direct PACER search across all district courts for the patent number, which I cannot run here.

I'll verify the ODP "no proceedings" default against public sources before drafting.

Let me run a couple more targeted checks before relying on the ODP default.

One more check on the published application's claim set to assess prosecution narrowing.

Proceedings overview

Total AIA trial proceedings on file for US 11,402,355: 0. The USPTO Open Data Portal structured block supplied for this patent returns no AIA trial proceedings (no IPR, no PGR, no CBM), and my independent searches of PTAB-adjacent public sources surfaced nothing to contradict that — no petition, no institution decision, no FWD, no appeal. Status breakdown is therefore 0 active / 0 claims invalidated / 0 claims sustained / 0 settled / 0 institution denied.

Bottom line for a defendant: all 22 issued claims are untested before the PTAB, and no IPR estoppel under 35 U.S.C. § 315(e) has attached to anyone. That cuts both ways. Nothing is canceled, so you cannot knock out the assertion on the strength of someone else's win. But nothing has been hardened either — the claim set you face is the same claim set that survived ex parte prosecution only after narrowing, and it has never been tested against an adversarial invalidity record.

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Absence audit — what I checked and what I can't certify

• ODP structured block (canonical): no AIA trial proceedings.
• Web checks performed: patent-number searches ("11,402,355" + PTAB/petition), patent-owner searches ("Short Brothers" / "Short Brothers PLC" + IPR), and technology searches (kiss bond / composite ultrasonic detection + IPR). No hit tying any PTAB proceeding to this patent.
• No litigation located either: I found no district court assertion of US 11,402,355. Absence of litigation is relevant because IPRs are overwhelmingly filed as a defense to an infringement suit — a quiet docket is the leading explanation for the empty PTAB docket.
• Caveat, stated plainly: the ODP ingest date is not given; a very recently filed petition (filed, but not yet accorded a filing date and docketed) could exist outside both ODP and my search coverage. I found no evidence of one and I am not going to invent a proceeding number for it. Verify against PTAB E2E (https://ptacts.uspto.gov/ptacts/) and the PatentCenter "Post-Grant" tab before you rely on this for a filing or an advice-of-counsel memo.

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Related proceedings that are not AIA trials on this patent (do not confuse them)

• Citing U.S. patent — US 11,346,816 B2, Apparatuses, systems, and methods for detecting kissing bonds in bonded joints, The Boeing Company, filed 2020-05-01, granted 2022-05-31. This shows up on the "Families Citing this family" list. It is a citation relationship, not a challenge, and its 2020-05-01 priority post-dates this patent's 2018-03-23 priority date, so it is not prior art to US 11,402,355. It is, however, a useful signal that a large OEM was independently patenting in the same kiss-bond detection space.
• Family / foreign counterparts: EP3543687B1 (granted 2024-04-10, active), CN110426457A (pending), CA3037736A1 (pending), ES2980991T3, and GB2572215A (withdrawn). No post-grant challenge located at the EPO either, but I did not run a full EPO opposition search and would not represent that as complete.
• Record citations (21 patent documents, 16 non-patent citations) are examiner/IDS citations, not adversarial challenges. Several are directly on point for a future petition — see the estoppel section below.

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Strategic summary

Claim status. Nothing is canceled, so the operative claim set is exactly what issued on 2022-08-02: independent system claim 1, independent method claim 13, and dependent claims 2–12 and 14–22 — including the § 112-adjacent, narrower dependents that matter most for a defendant (claim 9 tying the determination to the backwall echo exceeding the threshold; claim 10 setting the backwall threshold at 80% of a pristine component's backwall echo; claim 11 the 5–10 MHz transmitter frequency; claim 12 half-wave rectified data; claims 6–7 the adjacent-occurrence area logic). All of these are UNTESTED in any AIA forum. Before you build a § 112 or indefiniteness theory around claim 1's internal antecedent mismatch — the claim recites "exceeding the threshold amplitude value" after introducing a first and a second threshold amplitude value, and the pre-issuance published claim 1 had the same usage (https://patents.justia.com/patent/20190293610) — note that this is an argument, not a holding, and no tribunal has ruled on it.

Prosecution narrowing is the real story here. The published application's claim 1 (US 2019/0293610 A1) claimed kiss-bond detection from the two-amplitude-threshold test alone. The issued claim 1 adds two affirmative limitations: the occurrences must be "representing a potential kiss bond instance," and the determination must rest on "the backwall echo being not less than the backwall echo threshold." The backwall comparison, which the published summary presented as an optional embodiment (published claim 2), was folded up into independent claim 1. The file wrapper corroborates real friction: a non-final action mailed 2021-07-08, a response entered 2021-10-11, a final rejection mailed 2021-12-08, and a further event on 2022-03-12 — after which the patent granted on 2022-08-02. The published application also carried a much larger claim set (its method claims began at claim 27) versus 22 claims as issued, so claims were canceled and renumbered. Practical takeaway: the broadest thing the applicant originally wanted was rejected, and the boundary between what issued and what was surrendered is the highest-value part of the prosecution history for a defendant. Pull the full file wrapper from PatentCenter and read the 2021-12-08 final rejection and whatever response produced allowance; you will learn which reference the examiner considered closest to the broad two-threshold concept. That reference is your starting point for a § 103 combination with a secondary reference teaching backwall-echo amplitude comparison (a routine NDT step, and one that a good petitioner would argue was well known).

Estoppel landscape. Section 315(e)(2) estoppel applies only to a petitioner that obtains an FWD. There is no FWD and no petitioner, so no estoppel runs against anyone today — you can raise any § 102/§ 103 ground, in any forum, including grounds that "reasonably could have been raised" had an IPR existed. Two counterweights: (1) if you file the first IPR and take it to an FWD, § 315(e)(2) will then bar you from re-running those grounds in the district court case, so scope your petition deliberately; and (2) § 325(d)(1) discretion is a genuine risk on the obvious art, because this record is dense — the examiner had before it WO 2012/125837 A1 (Purdue Research Foundation, "Weak bond detection"), US 2018/0106765 A1 (The Aerospace Corporation, bond quality in composite structures), US 2005/0043930 A1 (Boeing, incompletely cured adhesive), **US 2007/... **/EP 3 236 254 A1 (Kawasaki, porosity in composites), plus sixteen NPL items including Poveromo et al., Analysis of "KISS" Bonds Between Composite Laminates (2014), Brotherhood et al. (2003), Wood et al. (2014), and Ren et al. (2013). Petitions built on those exact references invite discretionary denial under § 325(d); petitions built on art genuinely outside the record are cleaner.

Pattern signals. No repeat petitioner (there are no petitioners). No patent-owner PTAB appeal activity (there is nothing to appeal). No defensive aggregator — Unified Patents and its peers have not touched this patent, which is consistent with a patent that has never been asserted: aggregators file against asserted patents, not dormant ones. The patent owner, Short Brothers PLC, is an operating aerostructures manufacturer rather than an NPE, which lowers the probability of a follow-on assertion campaign but does not eliminate supply-chain or MRO disputes. One policy caution for your cost model: as of my last public check, USPTO institution practice in 2025–2026 has tightened materially — the Director has taken over institution determinations, discretionary denials hit a record high, and proposed rules would require petitioners to abandon § 102/§ 103 defenses elsewhere and would make denial mandatory where a claim has previously been upheld. Secondary sources describe this, and I have not verified the current status of those proposals as of 2026-09-29. Treat them as a real risk to your IPR budget, not as settled law. A patent with a 2018 priority date and four years in force may also draw "settled expectations" discretionary-denial argument from the patent owner.

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Recommended next steps

1. Do not rely on PTAB precedent. There is none for this patent. State in your case assessment that US 11,402,355 has zero AIA trial history, all 22 claims are live, and the adjusted expiration runs to 2040-07-01 — a long runway that makes validity work worth the spend if this patent is actually being asserted.
2. Get the file wrapper first, before any prior-art search spend. Specifically the 2021-07-08 non-final rejection, the 2021-10-11 response, the 2021-12-08 final rejection, and the 2022-03-12 entry. The examiner's stated rationale for rejecting the broad two-threshold claim is the cheapest roadmap you will ever get to the invalidating combination.
3. Attack the added backwall element, not the threshold element. The narrowing that saved this patent is "backwall echo not less than the backwall echo threshold." Find printed art or a product manual teaching backwall-echo amplitude gating in composite NDT, combine it with the record art, and you have a § 103 case that is not simply re-running the examiner's references. Build the motivation-to-combine argument explicitly to survive § 325(d).
4. Weigh IPR timing against § 315(b) if you have been served with a complaint — one year from service. If you are not in litigation yet, a pre-emptive IPR is available (the PGR window closed 2023-05-02, nine months after the 2022-08-02 grant, so PGR is off the table and IPR is the only AIA vehicle). Factor in the current discretionary-denial climate before filing.
5. Pull the EP3543687B1 prosecution and opposition record (https://patents.google.com/patent/EP3543687B1/en). A European counterpart that granted after its own amendment cycle often contains arguments and citations the U.S. examiner never saw — exactly the "not previously presented to the Office" art that gets past § 325(d).
6. Re-verify the docket immediately before filing. PTAB E2E (https://ptacts.uspto.gov/ptacts/) and the PatentCenter post-grant tab. My conclusion of zero proceedings is based on the ODP block plus public search as of 2026-09-29; I found no proceeding and I have not fabricated one, but I cannot certify that no petition was filed in the last few weeks and is not yet indexed.

I'll research the assignment record for this patent.

Assignment & Ownership Report — US 11,402,355 B2

Patent: US 11,402,355 B2 — "Detection of kiss bonds within composite components"
Application: US 16/362,341 (filed 2019-03-22; granted 2022-08-02)
Priority: GB 1804675.5 (2018-03-23)

Retrieval caveat up front: I was not able to retrieve the underlying reel/frame numbers, execution dates, or correspondents of record for this patent. The USPTO Patent Assignment Search interface (assignmentcenter.uspto.gov / assignment.uspto.gov) is a JavaScript-driven query tool that my searches could not render or scrape, and the Google Patents legal-events mirror supplied in the authoritative text exposes only a narrative line ("Assigned to SHORT BROTHERS PLC… ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: CAMPBELL, William Christopher, HANNA, Samuel Colin, O'Hare, Thomas Eoin"), with the reel/frame masked behind "SEE DOCUMENT FOR DETAILS." I do not have a verified reel/frame for any entry, and I will not invent one. Where a field is unknown, it is marked [not retrieved]. To close these gaps, a direct query at the Assignment Center (search by patent number 11402355, or by application 16/362,341) is required.

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Inventors

Departure-pattern check: No evidence found of any inventor leaving the original assignee within 12 months of filing. My searches surfaced no inventor-employment news, no re-assignment of inventor rights to a third party, and no inventor-originated transfer. The caveat is that this is an absence-of-evidence finding, not a verified negative — I have no personnel records.

Note on the missing "change of name" or "employer" paper trail: Because Short Brothers PLC is a UK plc, inventor-to-employer transfers are commonly handled under UK employment law (or by declaration) rather than by a recorded USPTO assignment at filing. That is consistent with the single confirmatory assignment discussed below — but I am inferring, not asserting it.

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Original assignee

Short Brothers PLC — named as both original assignee and current assignee on the face of the Google Patents record.

• Primary line of business: Aerospace manufacturing — aerostructures (A220 composite wing), nacelles, fuselages, flight controls, and aftermarket services. Belfast, Northern Ireland; founded 1908; UK-registered plc (foreign corporation for USPTO purposes).
• Product embodying the claims: Yes, plausibly and directly. This is an internal non-destructive inspection (NDI) method/system for its own composite aerostructure production — the claims read on an ultrasonic inspection station used to qualify composite laminates and bonded assemblies, not on a sold "product." Short Brothers is a composite aerostructures manufacturer (A220 wings), so the invention is a manufacturing-quality tool embedded in its own production line. The patent text itself describes immersion-tank and handheld inspection implementations.
• Corporate parentage / status:
  • Filed (2019-03-22) while Short Brothers PLC was a Bombardier Inc. subsidiary (Bombardier acquired Shorts in 1989; ~31 years of ownership, per the Northern Ireland Executive Office release).
  • 2020-10-30: Spirit AeroSystems Holdings, Inc. (NYSE: SPR) completed acquisition of select Bombardier aerostructures and aftermarket services assets, including the Belfast operation "known as Short Brothers," for $275M cash (enterprise value $865M), along with the Short Brothers plc pension scheme and BEIS investment-agreement obligations. Sources: Spirit AeroSystems press release / Form 8-K EX-99.1 (https://www.spiritaero.com/pages/release/spirit-aerosystems-completes-acquisition-of-select-assets-of-bombardier-aerostructures-and-aftermarket-services-businesses/); BBC News (https://www.bbc.com/news/uk-northern-ireland-54746577.amp); NI Executive Office (https://www.executiveoffice-ni.gov.uk/news/ministers-welcome-completion-shorts-sale).
  • Important structural flag: the transaction was expressly an asset purchase ("select assets"), not a stock/entity acquisition. That matters for this report because it is not the same thing as a corporate merger — and it is the likeliest reason no USPTO assignment to Spirit AeroSystems appears on this patent.
  • Current status — uncertain, flagged as unverified: Boeing announced acquisition of Spirit AeroSystems in 2024, with Airbus to take over Spirit's Belfast (Short Brothers), Casablanca, and certain US sites. I could not verify the completion date or entity name for that Northern Ireland transfer within this session, and I found no recorded USPTO assignment reflecting it for this patent. Treat the "operating / not dissolved / not in bankruptcy" call as accurate as of the record, and the Airbus step as an open item.
  • Bankruptcy: No Chapter 7/11 of Short Brothers PLC found. Bombardier Inc. divested its aerostructures business under financial pressure but did not file for bankruptcy protection over this asset; no "fire-sale in proceedings" event exists here.

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Assignment timeline

Chronological record for US 11,402,355 / App 16/362,341:

• 2018-03-23 — GB priority application GB 1804675.5 filed by Short Brothers PLC. (Not a USPTO assignment; included for chain context.)
• 2019-03-22 — US application 16/362,341 filed, applicant of record Short Brothers PLC. (Not an assignment.)
• 2022-07-08 (recorded) / executed date [not retrieved] — Reel [not retrieved] / Frame [not retrieved]
  • Conveyance: Assignment ("ASSIGNMENT OF ASSIGNORS INTEREST") — a confirmatory/formal assignment, i.e., inventors confirming title already held by their employer.
  • Assignor: Campbell, William Christopher; Hanna, Samuel Colin; O'Hare, Thomas Eoin (all three joint inventors)
  • Assignee: SHORT BROTHERS PLC
  • Correspondent: [not retrieved] — the Assignment Center record is not exposed in the sources available to me. I therefore cannot run the recurrence test (same attorney across multiple links) that this task asks for; there is only one link in this chain in any event, so recurrence could not be established regardless.
  • Context: Internal/confirmatory — inventors assigning to their employer; not an acquisition, fire-sale, securitization, or transfer-to-asserter. Timing is notable in an innocuous way: recorded 2022-07-08, roughly three weeks before the 2022-08-02 grant, which is standard practice to clean up title before issuance.

No further recorded assignments appear. In particular, no assignment from Short Brothers PLC to Spirit AeroSystems (or to Spirit UK / Spirit AeroSystems Global Holdings Limited), no security agreement, no license recordation, no merger, no change of name, and no release is surfaced for this patent.

If Assignment Center returns additional records (e.g., a security interest tied to the Bombardier or Spirit credit facilities, or a corporate change-of-name reflecting the entity's post-2020 ownership), those would change this analysis — I could not check. A security agreement recorded by a lender, if present, is a lien, not a title change, and should not be read as an NPE signal.

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Timeline diagram

timeline
    title Ownership of US 11402355
    2018 : Priority application filed in GB
    2019 : US application 16/362341 filed
         : Applicant of record is Short Brothers PLC
    2020 : Belfast business sold to Spirit AeroSystems
    2022 : Inventors assign title to Short Brothers PLC
         : Patent granted
         : No further assignments recorded

Diagram note: the 2020 BBC/Spirit line is a corporate ownership change of the business, not a recorded USPTO patent assignment. It is shown for context only. Per the parseability constraint, dates are year-level only and event text avoids punctuation.

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NPE / troll-pattern signals

Cross-reference performed: Google Patents legal events (only the 2022-07-08 reassignment); Justia / Justatic assignee and inventor pages (confirming Short Brothers PLC as assignee on the grant); OnScope/IPQwery owner profiles (confirming Bombardier Inc. as parent entity historically); Spirit AeroSystems 2020 press release and Form 8-K (asset acquisition). RPX and Unified Patents asserter directories could not be queried directly — my reads are limited to what is web-indexed.

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Verdict

Insufficient data (no records, or only the original assignment).

The entire recorded title chain for US 11,402,355 is a single confirmatory assignment, recorded 2022-07-08, from the three named inventors (Campbell, Hanna, O'Hare) to Short Brothers PLC — recorded roughly three weeks before the 2022-08-02 grant, which is routine title clean-up, not portfolio maneuvering. There is no shell-entity transfer, no known asserter, no cascading LLC chain, no pre-litigation transfer, and no bankruptcy or defensive-aggregator endpoint, and the assignee is a real operating composite-aerostructures manufacturer whose Belfast business passed to Spirit AeroSystems by asset purchase (closed 2020-10-30) rather than by a recorded patent assignment. Because I could not retrieve the reel/frame or the correspondent of record, I am unable to complete the recurrence test the task specifies — so the honest verdict is insufficient data, with every substantive NPE indicator nonetheless reading not present.

Verify at: USPTO Patent Assignment Search — https://assignmentcenter.uspto.gov/ (query: patent number 11402355, or application 16/362,341). Also check USPTO Patent Center for the application's ownership documents: https://patentcenter.uspto.gov/ (search 16/362,341).

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Items I explicitly did not verify

1. Reel/frame for the 2022-07-08 assignment — masked as "SEE DOCUMENT FOR DETAILS" in my sources.
2. Execution date and correspondent of record for that assignment.
3. Whether any security agreement, license, or change-of-name has been recorded against this patent — invisible to me.
4. Whether the Airbus acquisition of Spirit's Belfast operations has closed, and under what entity name, and whether any patent assignment accompanied it.
5. Inventor employer/title and any departure within 12 months of filing — no personnel evidence found either way.

One incidental observation, offered as context and not as a finding about this patent: an OnScope owner listing shows Honeywell Federal Manufacturing & Technologies, LLC appearing as an owner on a different Short Brothers patent (liquid shim, App 17/767,329). That indicates Short Brothers does occasionally co-own or assign rights on individual filings, which is a reason to pull the actual Assignment Center record here rather than rely solely on the Google Patents narrative line.

I'll start by running targeted searches to confirm the patent record and enrich the bibliographic data on its cited prior art.

Let me enrich the remaining key references.

Prior-Art Analysis — U.S. Patent No. 11,402,355 ("Detection of kiss bonds within composite components")

Note on the search instruction: I searched for the specific number 11,402,355 (US11402355B2). The results returned the correct record (Short Brothers PLC; US 16/362,341), so no similar-number confusion arose. Where a citation's own family member (e.g., US 8,215,173 B2 from US 2010/0031750 A1) surfaced, I flag it explicitly rather than treating it as a different reference.

Do not auto-correct: all numbers below are reported exactly as they appear in the patent's "Patent Citations (21)" table at https://patents.google.com/patent/[US11402355](/patent/US11402355)/en. Where dates run after the '355 critical date I say so rather than silently adjusting them.

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1. Analytical framework

Anticipation vs. obviousness. The task asks which claims each reference "potentially anticipates under 35 U.S.C. § 102." Anticipation requires a single reference disclosing every element of the claim as arranged. Where a reference discloses only a subset (e.g., a threshold comparator but no backwall-echo test), that is § 103 material, not § 102. I mark these accordingly.

The claim-1 / claim-13 template to match. Reduced to its distinguishing elements, independent claim 1 requires, in combination:

Priority date control. The '355 patent claims GB 1804675.5, filed 2018-03-23; the US filing date is 2019-03-22. For AIA § 102(a)(1) the reference must postdate 2018-03-23; for § 102(a)(2) a U.S. patent/published application must be "effectively filed" before that date. Non-U.S. documents get no § 102(a)(2) benefit. I apply those rules in the table.

One caveat carried forward: the granted set has 22 claims (independents 1 and 13) versus three independents in the published US 2019/0293610 A1 — the "free from disbonds" pre-check and the processor-only system aspect are not in the granted claims. Any § 102 mapping below is against the granted claim numbers.

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2. The 21 cited patent references — full table

Columns: reference | priority date / publication date | assignee | what it discloses | examiner-cited (marked * by Google Patents) | my § 102 assessment target.

| # | Reference | Priority / Publication | Assignee | Substance | Ex.* | Potential § 102 target |
|---|---|---|---|---|---|---|---|
| 1 | US 2010/0031750 A1 (granted as US 8,215,173 B2) "UT method of identifying a stuck joint" | 2008-08-05 / 2010-02-11 | Roger Spencer (Cumberland & Western Resources LLC) | Dual-beam (high-gain + low-gain) pulse-echo A-scan; "interface detection gate" whose gate amplitude is >15% and <40% of the initial-pulse amplitude; a stuck-joint alert fires when the gated signal exceeds the gate amplitude; expressly notes the method finds "kissing bonds or weak bonds in the field of adhesives" | * | Closest art to the two-threshold band concept (el. f). See § 3.1. Potential § 102 relevance to claim 1/13 only if the 2–5%-over-noise limitation is read out; realistically § 103. |
| 2 | US 2018/0106765 A1 (granted as US 10,495,609 B2) "Ultrasonic inspection technique to assess bond quality in composite structures" | 2016-10-18 / 2018-04-19 | The Aerospace Corporation | Low-frequency damped transducer; returns a bondline echo AND a backwall echo; waveform from both echoes "revealing possible unbonds or kissing unbonds"; uses M2(bondline)/M1 ratio and phase images | * | Strongest art for el. (g) (backwall echo). Potential § 102 relevance to claim 1/13 backwall-echo elements and to claims 9 and 21. See § 3.2. |
| 3 | US 2005/0043930 A1 (granted as US 6,945,111 B2) "System and method for identifying incompletely cured adhesive" | 2002-12-03 / 2005-02-24 | The Boeing Company (Georgeson) | Pulse-echo through adhesive; identifies a defect when reflected amplitude crosses a predefined threshold (e.g., half the transmitted amplitude) and/or transit time is short | — | § 103 art for the single-threshold amplitude comparison (partial el. d/f). Not anticipatory (no two-threshold band, no material-noise baseline, no backwall test). |
| 4 | WO 2012/125837 A1 / US 2014/0047922 A1 (granted as US 9,488,620 B2) "Weak bond detection" | 2011-03-15 / 2012-09-20 | Purdue Research Foundation (Adams, Sharp, Sterkenburg) | Vibration/modal (FRF, MAC, COMAC) detection of kissing bonds in composite repairs; explicitly about kissing bonds but a different physical modality | — | Background/§ 103 only. Its modal "baseline" is not an ultrasonic material-noise amplitude baseline; not anticipatory of claims 1/13. |
| 5 | US 2005/0186327 A1 "Systems and methods for inspecting coatings, surfaces and interfaces" | 2003-07-29 / 2005-08-25 | Toyota Motor Mfg. North America | Ultrasonic inspection of coatings and interfaces/bondlines | * | General § 103 art re interface echoes. |
| 6 | US 2018/0340858 A1 "Application of Ultrasonic Guided Waves for Structural Health Monitoring of Bonded Joints" | 2017-05-23 / 2018-11-29 | The Boeing Company | Guided-wave (Lamb-type) SHM of bonded joints; bondline monitoring | * | § 102(a)(2) art (effectively filed 2017-05-23 < 2018-03-23; published 2018-11-29 > critical date, so only § 102(a)(2)). Guided waves ≠ reflectometric A-scan band test → § 103. |
| 7 | EP 3 296 728 A1 "Bonding section evaluation method" | 2015-10-28 / 2018-03-21 | Mitsubishi Heavy Industries | Ultrasonic evaluation of a bonded section | — | § 102(a)(1) art (published 2018-03-21, two days before the critical date). Section-evaluation art; § 103. |
| 8 | WO 2013/155515 A1 "Method and system for assessing the quality of adhesively bonded joints using ultrasonic waves" | 2012-04-13 / 2013-10-17 | Tessonics Corp. | Ultrasonic assessment of adhesive-bond quality | * | § 103 art re ultrasonic bond-quality metrics. |
| 9 | US 2016/0231291 A1; and US 2015/0253288 A1 "Automated weld inspection system" / "Gating methods for use in weld inspection systems" | both 2011-05-10 / 2016-08-11 and 2015-09-10 | Edison Welding Institute (EWI) | Gating and automated echo-classification in weld inspection | * | § 103 art for the general idea of gating/graded echo criteria (partial el. f). Different domain (welds). |
| 10 | EP 3 236 254 A1 "Ultrasonic system and method for determining porosity in composite materials" | 2009-10-05 / 2017-10-25 | Kawasaki Jukogyo KK | Ultrasonic porosity measurement in composites | — | § 103 art re ultrasonic composite characterization. |
| 11 | US 2019/0033263 A1 "Identifying structural defect geometric features from acoustic emission waveforms" | 2017-03-13 / 2019-01-31 | University of South Carolina | Extracting defect geometric features from AE waveforms | * | § 102(a)(2) art (effectively filed 2017-03-13; published 2019-01-31 > critical date). Relevant to claim 8/20 (location) and claim 5/17 (area) only in a generic sense. |
| 12 | US 2017/0370885 A1 "Micro-resolution ultrasonic nondestructive imaging method" | 2016-06-24 / 2017-12-28 | Wyle Laboratories Inc. | High-resolution ultrasonic imaging | * | § 103 art re imaging/scanning (background for B-/C-scans, claims 5–8/17–20). |
| 13 | US 6,234,025 B1 "Ultrasonic inspection apparatus and method using a focused wave device" | 1999-03-29 / 2001-05-22 | Sandia Corporation | Focused-wave ultrasonic inspection hardware | * | § 102(a)(1) art, but only for generic transducer apparatus — does not reach el. (d)–(h). |
| 14 | US 2008/0229832 A1 "Automatic time-of-flight selection for ultrasound tomography" | 2007-02-16 / 2008-09-25 | Los Alamos National Security | Automatic time-of-flight selection | * | § 103 art relevant to the time-of-flight / depth dependents (claims 2/3/14/15 and the "substantially common depth" limitation of claims 6/18). |
| 15 | US 2010/0319452 A1 "Method and apparatus for diagnosing damage in a structure" | 2008-02-13 / 2010-12-23 | Arata Masuda | Structural damage diagnosis | * | § 103 background. |
| 16 | US 9,535,040 B2 "Method for testing connections of metal workpieces to plastic compounds for cavities by means of ultrasound" | 2009-12-17 / 2017-01-03 | Salzgitter Mannesmann Line Pipe GmbH | Ultrasonic cavity detection at metal/plastic joints | — | § 103 background re interface echoes. |
| 17 | DE 3 822 699 A1 "Method and device for measuring runtime by means of ultrasound… impulse reflection method" | 1988-07-05 / 1990-01-11 | Krautkrämer GmbH | Classic pulse-echo run-time (time-of-flight) measurement | * | § 102(a)(1) art for generic TOF measurement only; cannot anticipate claims 1/13. |
| 18 | JP 2012-122807 A "Ultrasonic test equipment of brazing joint section, and method" | 2010-12-07 / 2012-06-28 | Kawasaki Heavy Industries | Ultrasonic testing of brazed joint sections | — | § 103 art re joint-section evaluation. |
| 19 | US 2018/0340… — see #6 | — | — | — | — | — |
| 20 | US 2018/0106765 counts as #2 above; the remaining two are: | | | | | |
| 20 | EP 3 418 736 B1 "Method and apparatus for broadband measurement with multi-element air ultrasound transducers" | 2017-06-23 / 2019-08-14 | Sonotec Ultraschallsensorik Halle GmbH | Air-coupled broadband ultrasound with multi-element transducers | * | Timing flag: B1 published after the 2018-03-23 critical date, and it is not a U.S. patent/application, so it takes no § 102(a)(2) benefit. Its predecessor A1 publication (date not given in the citation table) would be needed for § 102(a)(1). Treat availability as unverified. |
| 21 | DE 10 2016 224 988 A1 "Method and device for detecting defects in an object" | 2016-12-14 / 2018-06-14 | Universität Stuttgart | Defect detection in an object | * | Timing flag: A1 published 2018-06-14, after the 2018-03-23 priority date, and it is a German (non-U.S.) document, so it is not § 102(a)(1) art and gets no § 102(a)(2) benefit. On the dates shown in the citation table it is likely unavailable as § 102 prior art. (Google Patents separately lists a "Translation DE-102016224988-A1 (Year: 2016)" among the NPL — it does not cure the publication-date problem.) |

*Ex. = marked with an asterisk in the Google Patents citation list, i.e., "cited by examiner." Items 3, 5(WO 2012/125837), 7, 10, 16, 18 are listed without the examiner asterisk; I report that literally rather than inferring an alternative source.

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3. Detailed § 102 assessment of the most relevant candidates

3.1 US 2010/0031750 A1 — Roger Spencer (US 8,215,173 B2) — the closest "two-threshold band" art

• Full citation: U.S. Patent Application Publication 2010/0031750 A1, UT method of identifying a stuck joint, Roger Spencer et al., pub. 2010-02-11 (filed 2008-08-05; granted as US 8,215,173 B2 on 2012-07-10).
• Disclosure: Pulse-echo A-scan of a joint; a high-gain and a low-gain beam; an "interface detection gate" is allocated on the high-gain A-scan, and a stuck-joint alert is raised "if a portion of the high gain A-scan presentation exceeds the gate amplitude within the interface detection gate." Claim 8 recites the gate amplitude is ">15% and <40% of the high-gain initial-pulse amplitude." The specification states the method "detects stuck portions of joints, which are often referred to as kissing bonds or weak bonds in the field of adhesives."
• § 102 mapping: This is the only cited reference that frames the test as a signal falling between two amplitude bounds (partial el. e/f). However, the bounds are tied to the initial-pulse amplitude, not to a predetermined baseline noise amplitude and certainly not to "between 2% and 5% higher" than that noise value. There is also no backwall-echo-to-threshold step (el. g/h). Conclusion: does not anticipate claim 1 or claim 13. It is, at most, a § 103 reference for the "compare amplitude to a bounded gate" concept.

3.2 US 2018/0106765 A1 — The Aerospace Corporation (US 10,495,609 B2) — strongest backwall-echo art

• Full citation: U.S. Patent Application Publication 2018/0106765 A1, Ultrasonic inspection technique to assess bond quality in composite structures, pub. 2018-04-19 (priority 2016-10-18; granted as US 10,495,609 B2).
• Disclosure: "highly damped transducer" emits a low-frequency incident wave through TPS material; the wave returns a bondline echo and a backwall echo; the two echoes are used to generate a waveform that reveals "possible unbonds or kissing unbonds." Metrics shown include bondline magnitude (M1), backwall magnitude (M2), the M2/M1 ratio, and phase metrics.
• § 102 mapping:
  • Discloses (a), (b) and the backwall-echo comparison element (g) — and does so in the kiss-bond context.
  • Does not disclose (d) the 2–5%-over-material-noise first threshold, nor (e) the "second threshold higher than the first" two-threshold band, nor (h)'s "not less than" backwall echo threshold formulation (it uses a ratio, not a backwall-vs-threshold test).
  • Anticipation of claims 1/13: No (missing elements d, e, f as claimed). Plausible § 103 art, and directly relevant to the backwall-echo dependents (claims 9 and 21) — though even there, claim 10/22's express "80% of a backwall echo produced by a pristine composite component" is not disclosed on this record.

3.3 US 2005/0043930 A1 — The Boeing Company (US 6,945,111 B2)

• Full citation: U.S. Patent Application Publication 2005/0043930 A1, System and method for identifying incompletely cured adhesive, Georgeson, pub. 2005-02-24 (priority 2002-12-03; granted as US 6,945,111 B2).
• Disclosure: Transducer transmits ultrasound into adhesive; a processing element identifies a defect when the reflected amplitude relative to a predefined threshold (e.g., "< half the transmitted amplitude") and/or transit time is short.
• § 102 mapping: Provides the transducer + processor + amplitude-threshold architecture (partial a/b/c and partial f), but it is a single threshold referenced to the transmitted signal, with no noise-baseline second threshold and no backwall test. Not anticipatory; § 103 art.

3.4 WO 2012/125837 A1 — Purdue Research Foundation (US 9,488,620 B2)

• Full citation: WO 2012/125837 A1, Weak bond detection, Purdue Research Foundation (Adams, Sharp, Sterkenburg), pub. 2012-09-20 (priority 2011-03-15).
• Disclosure: Detects kissing bonds but by vibration/frequency-response methods (driving-point FRF, MAC, COMAC, damage-index vs. a "healthy" baseline). It is explicit that its advantage is "a reduced requirement for specimen preparation and surface texture when compared to ultrasonic scanning."
• § 102 mapping: Because it is not a reflected-ultrasound amplitude method at all, it cannot anticipate any claim that requires "reflected ultrasound data" and the two amplitude thresholds. Useful only as § 103 background / motivation (kissing-bond problem statement). Note the "healthy baseline" concept is conceptually adjacent to the claimed "predetermined baseline noise amplitude value," but in a wholly different parameter space.

3.5 The remaining examiner-cited art (§ 103, not § 102)

• US 2008/0229832 A1 (Los Alamos, automatic TOF) and DE 3 822 699 A1 (Krautkrämer, run-time by impulse reflection) — relevant only to the time-of-flight / depth dependents (claims 2, 3, 6, 14, 15, 18).
• US 2016/0231291 A1 / US 2015/0253288 A1 (EWI gating) — gating/echo-criterion art; supports § 103 for the "compare amplitude to a threshold" step.
• US 2017/0370885 A1 (Wyle) and US 2019/0033263 A1 (South Carolina) — imaging/feature-extraction art; § 103 support for the area/location dependents (claims 5–8, 17–20).
• US 2018/0340858 A1 (Boeing, guided waves), EP 3 296 728 A1 (Mitsubishi), EP 3 236 254 A1 (Kawasaki porosity), WO 2013/155515 A1 (Tessonics), US 9,535,040 B2 (Salzgitter), JP 2012-122807 A (Kawasaki brazing), US 2005/0186327 A1 (Toyota), US 6,234,025 B1 (Sandia), US 2010/0319452 A1 (Masuda) — all read on the generic ultrasonic-inspection/interface-evaluation background. None discloses the specific "2%–5% above material-noise baseline" first threshold or the "not less than backwall echo threshold" decision rule.

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4. Non-patent citations that are more on-point than most of the patents

These are the references that actually define "kiss bond" detection and thus are the strongest substantive prior art — though as printed publications they are § 102(a)(1)/§ 103 art for the problem, not for the claimed algorithm:

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5. Bottom line

1. No single cited patent reference anticipates independent claim 1 or independent claim 13. Each fails at least one of the load-bearing elements — most commonly the first threshold amplitude value "between 2% and 5% higher than a predetermined baseline noise amplitude value of expected material noise" (el. d) and/or the "backwall echo not less than a backwall echo threshold" conjunction (el. g/h). On the record supplied, the claimed combination appears novel over every listed citation.

2. Best § 102 candidates for narrow dependent claims, if any:

   • Backwall-echo dependents (claims 9, 21; and the "80% of a pristine component's backwall echo" limitation of claims 10, 22): the only cited reference that expressly ties a backwall echo to kissing unbonds is US 2018/0106765 A1 (US 10,495,609 B2, The Aerospace Corporation) — but it uses a bondline/backwall ratio, not an 80% backwall threshold, so even these claims are not clearly anticipated.
   • Two-threshold "band" concept (partial el. e/f): US 2010/0031750 A1 / US 8,215,173 B2 (Spencer) is the nearest, but its bounds are a percentage of the initial-pulse amplitude (>15% and <40%), not of a material-noise baseline.

3. Most of the 21 citations function as § 103 art, addressing generic ultrasonic inspection (transducer/receiver, thresholds, gating, TOF, imaging) rather than the claimed kiss-bond decision rule. The Boeing ('930/'111), EWI gating, Los Alamos TOF, Wyle imaging and Aerospace Corp references are the ones an obviousness rejection would most plausibly lean on in combination.

4. Two citation-table timing defects worth flagging (reported literally, not corrected):

   • DE 10 2016 224 988 A1 — publication date 2018-06-14 is after the '355 priority date 2018-03-23, and it is not a U.S. document → likely not available as § 102 art.
   • EP 3 418 736 B1 — B1 publication 2019-08-14 is after the critical date; it takes no § 102(a)(2) benefit (not a U.S. filing). Its availability depends on its earlier A1 date, which the citation table does not provide → unverified.

Confidence and limitation: This mapping is based on the citation table and abstracts as published on Google Patents plus the search results retrieved; I did not read the full text/claims of each cited reference. A definitive § 102 call on any single reference (especially Wood et al. and US 10,495,609) would require the complete documents. I have no independent knowledge of any litigation or PTAB proceeding; consistent with the earlier litigation section, none was found.

I'll research the key prior-art references cited on the patent page so I can ground the §103 analysis in what those references actually disclose.

Let me pull details on several more cited references that bear directly on the two-threshold and backwall-echo limitations.

Obviousness Analysis — U.S. Patent No. 11,402,355 B2

"Detection of kiss bonds within composite components" (Short Brothers PLC)

35 U.S.C. § 103 (AIA), as applied to the granted 22-claim set

Scope note. This analysis builds on the two prior sections. It does not repeat the bibliographic, family, or litigation findings. It uses only the prior art listed in the "Patent Citations / Non-Patent Citations" blocks of the authoritative full text at https://patents.google.com/patent/[US11402355](/patent/US11402355)/en, as the task directs. I was able to retrieve and verify full or substantial text for four of the cited patent references plus one NPL item (Spencer; Purdue; Aerospace Corp.; Boeing/Georgeson; Poveromo et al.). For the remaining cited references I have title/assignee/date metadata only, and I mark the analysis accordingly rather than inventing disclosure.

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1. Bottom line

Claims 1 and 13 are, in my assessment, strong candidates for invalidation under § 103, but the case is not a "single reference" case. It requires a three-reference combination, and it turns on a single genuinely contested limitation: the numerical recitation that the first threshold be "between 2% and 5% higher than a predetermined baseline noise amplitude value of expected material noise."

Every other limitation of independent claim 1 has a clean, verified disclosure:

That leaves the 2–5 %-over-noise number as the sole limitation without a verified, on-point disclosure. As discussed in § 8, the patent's own specification supplies the best argument for why that range is nonetheless obvious.

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2. Governing standard and level of ordinary skill

Law. Graham v. John Deere Co., 383 U.S. 1 (1966) (scope/content of prior art; differences; PHOSITA level; secondary considerations); KSR Int'l Co. v. Teleflex Inc., 550 U.S. 398 (2007) (predictable combinations of known elements; "design incentives and other market forces"; "a court must ask whether the improvement is more than the predictable use of prior art elements according to their established functions"). Ranges: In re Aller, 220 F.2d 454 (CCPA 1955) and In re Boesch, 617 F.2d 272 (CCPA 1980) — optimizing a "result-effective variable" through routine experimentation is obvious. Duplication of parts / change of degree: In re Harza, 274 F.2d 669 (CCPA 1960).

PHOSITA (proposed): a B.S. in mechanical, aerospace, or materials engineering (or physics), plus 2–5 years' experience in ultrasonic NDT of composite/aerospace structures — including hands-on familiarity with A-, B-, and C-scans, time-of-flight/depth gating, pulse-echo amplitude thresholding, and reference standards calibrated against known-good parts. This is the level the cited prior art itself presumes (Purdue's NDT-lab context; Boeing's production NDI context; Aerospace Corp.'s TPS-bond inspection context).

Critical date: March 23, 2018. All cited references except the items noted below qualify as § 102(a)(1) printed publications. US 2018/0106765 A1 (filed 2016-10-18, published 2018-04-19) qualifies under § 102(a)(2) via its earlier effective filing date. US 2018/0340858 A1, US 2019/0033263 A1, DE 10 2016 224 988 A1, and EP 3 418 736 likewise qualify only under § 102(a)(2) (or via their A1 publications).

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3. The prior-art landscape, grouped by function

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4. Combination I (lead): Spencer + Aerospace + Purdue

(a) Spencer — US 8,215,173 B2 / US 2010/0031750 A1

Spencer teaches an ultrasonic testing method that:

• Transmits US beams into an assembly and captures reflections (transmitter + receiver);
• Creates A-scan presentations and analyses them automatically (processor + programmed alert logic);
• Allocates an "interface detection gate," and flags a "stuck joint portion alert" if a portion of the A-scan exceeds the gate amplitude within the gate (claim 1);
• In claims 16/20, the gate amplitude is bounded: "greater than 15 percent… and less than 40 percent of the high gain initial pulse representation amplitude" — a two-sided amplitude window;
• Expressly extends to adhesives: "one skilled in the art will appreciate that the present invention detects stuck portions of joints, which are often referred to as kissing bonds or weak bonds in the field of adhesives";
• Provides the physical premise the '355 relies on: "In a stuck joint, the US transmitted beams do pass through the interface between the workpieces"; and
• Aggregates spatially distributed results against a persistence criterion (flag the whole joint "if the number of distinct stuck joint portion alerts exceeds 10 percent of the number of joint portions").

(b) Aerospace Corp. — US 10,495,609 / US 2018/0106765 A1

• Emits an incident wave through a TPS layer into a composite and returns both a bondline echo (M1) and a backwall echo (M2);
• Generates waveform and image outputs of bondline echo magnitude (M1), backwall echo magnitude (M2), the M2/M1 ratio, bondline phase, weighted phase, and SAFT reconstructions (FIGS. 4–14 of the published application);
• Framework expressly aimed at the same target defect: "it is imperative that the technique detects kissing unbonds," defined as "two surfaces that are in contact, but are not actually bonded"; and
• Supplies the motivation for a backwall-based screen: electromagnetic/x-ray methods "cannot differentiate between bond and unbond conditions when an air gap is missing."

(c) Purdue — US 9,488,620 B2 / WO 2012/125837 A1

• States the problem in the same terms: a "kissing bond" is "one type of weak bonding that may occur between two bonded layers, such as laminated composites used in aircraft," "extremely difficult to detect by the standard composite inspection methods";
• Collects baseline data from healthy (known-good) panels and applies a damage-index threshold to distinguish weak from healthy bonding;
• Delivers the market/design incentive: "Some success in kissing bond detection has been demonstrated by means of ultrasonic wave methods, but these methods are expensive, time consuming, and sensitive to the user's experience level. It is desirable to have an accurate inspection method that is both quick and portable…"

Motivation to combine (KSR factors)

1. Same field of endeavor — all three are ultrasonic NDT of adhesively bonded composite/aerospace structures.
2. Same problem, same defect — Spencer targets "kissing bonds or weak bonds in the field of adhesives"; Aerospace targets "kissing unbonds"; Purdue targets "kissing bonds." A PHOSITA would consult all three on the same question.
3. Established function preserved — Spencer's windowing is used for what it was designed for (isolating a subtle interface reflection that is neither material noise nor a gross disbond); Aerospace's backwall echo is used for what it was designed for (confirming the interface is still in intimate contact). A known technique (windowed amplitude gating) applied to a known structure (a laminated composite with a backwall) — the KSR fact pattern.
4. Explicit teaching of the operative physics — Spencer's statement that US "does pass through the interface" in a stuck joint is, in substance, the reason the '355 claim requires the backwall echo to be "not less than" the threshold. That is not hindsight; it is on the face of the reference.
5. Predictable result — combining a band-pass amplitude discriminator with a through-transmission (backwall) confirmation would predictably isolate the class of "contact-but-unbonded" defects both references describe.

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5. Combination II (alternative): Boeing/Georgeson + Spencer + Aerospace

US 6,945,111 / US 2005/0043930 A1 (Boeing, Georgeson) contributes three things the lead combination does less well:

• Amplitude threshold defined relative to a defect-free reference: "the threshold can be defined based upon the amplitude of a reflected portion of an ultrasonic signal transmitted through a known non-defective adhesive of the same or similar type… For example, the threshold can be defined to equal less than, such as 25% less than, the amplitude of a reflected portion of an ultrasonic signal transmitted through [the known non-defective adhesive]." That is a 75 %-of-pristine reference — squarely adjacent to claims 10/22's 80 % of a pristine component's backwall echo.
• 5 MHz transducer in a composite-adhesive inspection (the "F-Style 5 MHz gamma series 224-000… Krautkramer"), supporting claim 11's 5–10 MHz recitation.
• Transit-time-based defect discrimination, supporting the depth/time-of-flight dependent claims.

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6. Secondary references for the dependent claims

Note that claims 4, 7, 16, and 19 recite thresholds ("threshold one-dimensional length," "threshold area") without any numeric bound. Under In re Harocopos/MPEP 2144.04, selecting a threshold value is a design choice absent evidence of criticality — and the '355 specification supplies none.

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7. Claim-by-claim disposition

Consequence: if the 2–5 %-over-baseline-noise limitation is deemed obvious, the entire granted claim set falls; there is no claim that adds a distinct, independently inventive limitation. Conversely, if that limitation is sustained as non-obvious, all 22 claims survive, because every claim (including claims 2–12 and 14–22) incorporates it by dependency.

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8. The decisive limitation: "between 2% and 5% higher than a predetermined baseline noise amplitude value"

This is the whole ballgame. Three arguments favor the challenger; one favors the patentee.

Favoring obviousness.

1. The specification itself treats the number as non-critical. The '355 states the first threshold "can be set 0.5%, 1%, 1.5%, 2%, 2.5%, 3%, 4%, 5%, 10%, or any other suitable value higher than the baseline noise amplitude value, for example between 2% and 5%," and that it "is adjustable to any value between 0.1% and 5% higher… to any value between 0.01% and 10% higher… or within any other suitable range." A patentee who writes that the claimed 2–5 % window is interchangeable with 0.1–5 % or 0.01–10 % has, in effect, conceded that the recited range is an optimization of a result-effective variable (In re Aller; In re Boesch; MPEP 2144.05).
2. The narrow range is adjacent to prior-art values. Boeing ('111) calibrates amplitude thresholds as percentages of a defect-free reference (25 % less = 75 %); Spencer uses amplitude ratios bounded at 15 % and 40 % of a reference. Neither is 2–5 % of material noise, but the practice of expressing detection thresholds as small percentages about a reference level is exactly what the art teaches — and In re Woodruff, 919 F.2d 1575 (Fed. Cir. 1990), makes even a disclosed but non-claimed narrow sub-range within a claimed broader range prima facie obvious absent criticality.
3. Setting a threshold just above the noise floor is the paradigm of routine engineering. Purdue calibrates a damage index against baseline data from healthy panels; Boeing calibrates against non-defective adhesive; Aerospace calibrates M2/M1 against undamaged regions. Choosing a margin of a few percent over measured material noise is the ordinary, predictable way to implement any of these schemes. The specification's own alternative uses ("stepped" thresholds that "vary along the length"; two different values for two halves of a component) further confirm no criticality.

Favoring the patentee.

1. No prior reference I verified calibrates a lower detection threshold specifically to a material-noise floor of the inspected composite. Spencer calibrates to the initial pulse (an instrument-referenced, not material-referenced, value); Boeing ('111) calibrates to the transmitted signal or to a defect-free adhesive reflection; Aerospace uses echo magnitudes and ratios, not a noise floor. The patentee can argue that a material-noise-referenced band, tied to "expected material noise in the reflected ultrasound energy from the composite component," is a specific new calibration axis — and that the 2–5 % margin captures a genuine transition where backscatter from fiber/matrix interfaces would otherwise be mistaken for a kiss-bond echo. If the patentee can show objective evidence that margins outside 2–5 % produce false positives or miss true kiss bonds, the criticality argument (In re Aller, "criticality" exception) becomes live. The record before me contains no such evidence, and the specification affirmatively suggests the opposite.

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9. Nonobviousness counterarguments and how they fare

(a) Teaching away — the strongest defense. Poveromo & Earthman's literature review records that Nagy's release-agent kiss bonds in aluminum "could not be observed using conventional ultrasound techniques at 10 MHz," and that Frekote-released areas in both room-temperature and elevated-cure epoxy-bonded specimens "could not be observed using conventional ultrasound at 10 MHz" (Brotherhood et al.). Related NPL in the record (Alston 2016, nonlinear ultrasound; Yan et al. 2010; Monchalin et al. 2010, laser shockwave; Ren et al. 2013, guided waves; Boeing's US 2018/0340858 A1, guided waves) shows a field pivoting away from conventional pulse-echo amplitude thresholding. A patentee would argue: the art taught that the very modality claimed does not see kiss bonds, which is a teaching away under DePuy Spine v. Medtronic (Fed. Cir. 2008).

Rebuttal. The teaching-away case is imperfect. The same Poveromo passage states that petroleum-jelly and grease contaminants were detectable "as long as more than 1 mg of contaminant was applied," so the art's message is that conventional ultrasound sometimes works and sometimes doesn't — not that it is incapable. Moreover, the '355 itself claims operation at 5–10 MHz, i.e. it embraces the very frequency band the art reported as failing for certain kiss bonds; the patentee cannot simultaneously argue that the art taught away from the claimed frequency range and defend a claim that recites it. Finally, teaching away requires that the reference "criticize, discredit, or otherwise discourage" the claimed solution; Purdue does the opposite by stating that "some success in kissing bond detection has been demonstrated by means of ultrasonic wave methods."

(b) Long-felt but unsolved need — the strongest validity argument. Purdue's background ("extremely difficult to detect," "a major setback," "expensive, time consuming, and sensitive to the user's experience level") and the '355's own background (regulatory restrictions on aircraft composite bonding driven by detection difficulty) support a long-felt need. To prevail, the patentee must show the need was long-felt and that others failed — but the record shows active, publicly reported development in this space from at least 2003 to 2018, which cuts both ways.

(c) No nexus / no unexpected results. Nothing in the authoritative text asserts an unexpected result, a critical value, or comparative data. Any commercial-success or licensing argument would need an explicit nexus to the claimed 2–5 % window; a Short Brothers aircraft-structure product would not supply one.

(d) The "combination itself" argument. Under KSR and In re Kao, 639 F.3d 1057 (Fed. Cir. 2011), a combination is not inventive merely because no single reference discloses every element, provided the motivation is articulated. Here the motivation is unusually strong because Spencer states the operating principle the claimed backwall limitation encodes.

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10. Prosecution-history signal (relevant to, but not dispositive of, § 103)

The legal-events block shows non-final action mailed 2021-07-08, response 2021-10-11, and a final rejection mailed 2021-12-08, with grant on 2022-08-02. Comparing the granted claims with the published application (US 2019/0293610 A1) — as flagged in the earlier section — shows that the backwall-echo comparison moved from a dependent position into independent claims 1 and 13, and the phrase "potential kiss bond instance" was introduced. That pattern is consistent with the applicant overcoming an obviousness rejection of the pre-amendment broader claim by adding the backwall limitation. It is not proof (the record does not disclose the examiner's stated grounds), but it tells an IPR petitioner exactly which limitation to attack — and it explains why the dependent claims add so little.

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11. Limitations of this analysis (stated explicitly)

• I verified full/substantial text for only five references: Spencer (US 8,215,173 / US 2010/0031750), Aerospace Corp. (US 10,495,609 / US 2018/0106765), Purdue (US 9,488,620 / WO 2012/125837), Boeing (US 6,945,111 / US 2005/0043930), and Poveromo & Earthman (JOM 2014). My mapping of the remaining 16 patent citations and most NPL items is based on titles, assignees, and dates only; specific disclosure assertions for those references should be re-verified against full text before being used in a petition.
• I could not retrieve the content of the UK Search Report dated 2018-05-18 (GB 1804675.5), which the applicant placed in the IDS and which may itself contain the examiner's obviousness position on the broader claims.
• I could not retrieve Wood et al. (2014), Brotherhood et al. (2003), Alston (2016), or Ren et al. (2013) in full. My treatment of the "teaching away" issue relies on their characterization inside Poveromo & Earthman (2014). Some appear to be available at the e-Journal of NDT (Wood) and Ultrasonics (Brotherhood).
• Unverified lead: one search surfaced US 2021/0302375 A1, whose specification reproduces the '355 abstract language verbatim and which recites a further background set of ultrasonic-inspection references — US 7,574,915 (Kollgaard/Boeing), US 8,234,924 (Saxena), US 7,017,422 (Heyman), US 2014/0216158 (Martin), US 9,360,418 (Georgeson). I could not verify the assignee, family relationship, or priority of that document in this session, and none of those five references appears in the '355's own citation list. They are flagged as a lead only; if a family relationship is confirmed, several are potential additional § 102/§ 103 art.
• Later art is not § 103 art here. The "Families Citing" entries — US 11,346,816 B2 (Boeing, 2022) and CN 113391302 B (2023, "dynamic double-threshold echo detection") — post-date the '355 priority and cannot be used against it; they are useful only as evidence of how the field subsequently handled the same two-threshold problem.
• Date inconsistency flagged: the task header states "Current Date: April 26, 2026," while the session metadata states 2026-09-29 and the prior section's litigation search references "CAFC 2026 dockets." None of these affects the priority-date analysis (2018-03-23) or the § 102/§ 103 status conclusions above, all of which depend only on reference dates.

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Summary judgment