US 11193858

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

Let me run a couple more targeted checks for litigation involving this patent's owner and any PTAB activity.

US 11,193,858 B2 — "Tissue planing assemblies and methods"

Note on the search request: I searched for this patent number specifically (exact-string and quoted variants) and also searched for litigation involving the assignee. I found no district court docket, no PTAB (IPR/PGR) proceeding, and no CAFC appeal involving US 11,193,858. Details and caveats on that search are at the bottom.

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1. Bibliographic data

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2. Abstract (verbatim, as issued)

"In one embodiment, a tissue planing assembly includes a base frame, a plurality of disassemblable components assembled to the base frame and having a ready configuration, a sample conveyor, a blade assembly configured to be coupled to the base frame, a control unit communicatively coupled to the sample conveyor, and one or more component sensors communicatively coupled to the control unit. The plurality of disassemblable components is configured to support a tissue sample. The sample conveyor is configured to convey the tissue sample through the blade assembly. The one or more components sensors are configured to output a signal indicative of at least one of the plurality of disassemblable components missing from the ready configuration, wherein the control unit prohibits operation of the sample conveyor when at least one of the plurality of disassemblable components is missing from the ready configuration."

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3. Plain-language overview of each independent claim

Claim 1 — "All-parts-present" interlock.
A tissue planing machine with a base frame and several parts that can be taken off and put back (front tray, rear tray, catch tray, hold-down roller, etc.). Those parts, when installed, define a "ready configuration." A powered conveyor feeds tissue through a blade assembly, driven by a control unit. The key limitation: component sensors (the spec describes them as magnetic/magnet in-position switches) signal the control unit whenever one of those removable parts is missing or not properly seated. If anything is missing, the control unit must prohibit the conveyor from operating. In short: a sensor-based assembly interlock that locks out the machine unless the removable components are all correctly installed.

Claim 11 — Two-hand control (anti-tie-down).
A simpler independent claim to the machine as such (base frame, sample conveyor through a blade assembly, control unit). The distinguishing limitation is that the machine has two separate hand controls wired to the control unit, and the control unit operates the conveyor only when both are activated simultaneously. The spec adds that the controls are spring-biased to the unactivated position, so both hands must stay engaged throughout the planing run; releasing either stops the conveyor. This is the classic two-hand, no-tie-down safety architecture (also keeps the operator's hands away from the blade).

Claim 17 — Adjustable-depth blade assembly.
Independent claim directed to the cutting head itself: a shoe with a groove, a blade sitting on the shoe's top surface near the groove, a blade clamp that rigidly clamps the blade to the shoe, and one or more spacers placed inside the groove adjacent to the blade to set the cutting depth. Different spacers (differing in where their fastener/dowel openings are formed) place the blade's leading edge at different positions, giving standardized graft thicknesses while keeping the blade rigidly fixed so thickness stays constant through a run.

Selected dependent claims (for context): front tray with pin-and-slot mounting (2–3); angled and rotatably adjustable rear tray (4–6); rear tray lockable in ready configuration (7); catch tray under the blade assembly (8); rotatable hold-down bar (9); tri-state status indicator giving ready / not-ready / running signals (10); pivoting control-unit housing with the two hand controls mounted on it (12–13); sensor-verified catch tray (14–15) and sensor-verified trays generally (16); gripping roller positioned relative to the blade cutting edge, with adjustable position (18); spacers behind the blade in the longitudinal direction (19); each spacer corresponding to a skin-graft thickness (20).

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4. Subject matter in one paragraph

The patent is a tissue-processing (skin-banking) apparatus. Full-thickness donor skin is laid epidermis-side down on a front tray and pulled by a toothed gripping roller through a fixed-depth blade assembly, producing a split-thickness skin graft (target ~0.3–0.65 mm, e.g. 0.45 mm) caught in a lower catch tray, while the dermis/adipose remainder rides over the blade clamp onto an angled rear tray. The disclosure emphasizes (a) larger graft widths than hand-held dermatomes, (b) tool-free disassembly of trays/roller for cleaning and sterilization between donors, and (c) safety logic — component sensors that disable the drive unless the machine is fully assembled, and dual hand controls that must both be held to run.

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5. Litigation / CAFC docket search — result and caveats

• No case found. Searches for the patent number in combination with docket/appellate terms returned no infringement suit, declaratory judgment action, IPR/PGR, or CAFC appeal naming US 11,193,858. Searches for the assignee (Community Blood Center / Community Tissue Services) plus "patent infringement" also returned nothing.
• Context from the record itself: the only third-party filings I could associate with the patent family are citations, not challenges — US 11,369,409 B2 (Medline Industries) and US 12,616,215 B2 (Meyn Food Processing). Neither is evidence of litigation.
• Confidence and limitations: I am not highly confident that no litigation exists. My tools are general web search, not a live PACER/CM-ECF, Docket Navigator, Unified Patents, or USPTO PTAB API query. A case filed recently, sealed, or indexed only behind a paid docket service could exist without appearing in these results. Treat "no litigation found" as "not located by open-web search" rather than a verified negative. Note also that a party may not have standing-triggered any docket activity at all for a device patent used internally by a tissue bank.

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6. Specific uncertainties / anomalies in the record

1. Claim 19 contains a typo in the granted text: "This tissue planing assembly of claim 17" (rather than "The"). I am reporting it literally, not correcting it.
2. "Hold down bar" vs. "hold down roller": claim 9 recites a "rotatable hold down bar," while the specification describes the removable component as a "hold down roller 172." This is an internal terminology discrepancy in the issued patent worth noting for any claim-construction analysis.
3. Expiration date 2040-10-02 is a Google Patents legal-status estimate reflecting patent term adjustment; it is not a legal conclusion and could shift with terminal disclaimers, maintenance-fee lapse, or later PTA recalculation.
4. Assignee name: the assignment record reads "Community Blood Center d.b.a Community Tissue Services." I have not independently verified the entity's current corporate form or address, so I am not asserting a location or corporate status beyond what the record states.
5. Family relationship: US 11,619,569 B2 is listed as a division of this application (same priority date 2018-05-01). If you need claim-by-claim coverage comparison across the two, that requires reading the '569 claims, which are not in the text I was given.

I'll search for litigation involving US patent 11193858 across the sources you mentioned.

Initial results are irrelevant. Let me refine with targeted searches.

Let me run a couple more targeted searches focused specifically on this patent number and its owner.

Proceedings overview

Total AIA trial proceedings on file for US 11,193,858: 0. The USPTO Open Data Portal returns no IPR, PGR, or CBM proceedings as of the most recent ingest, and my independent web searches surfaced no petition naming this patent. Breakdown by status is therefore all zeros: 0 active, 0 claims invalidated, 0 claims sustained, 0 settled, 0 institution denied. The defensive posture this gives a defendant is the opposite of "hardened": the patent's claims are entirely untested at the PTAB, which means you have a clean § 102/§ 103 runway with no § 315(e)(2) estoppel attaching to anyone, and no FWD to lean on — but also no free kill shot. You would be the first petitioner.

Caveat on search false positives (flagged, then excluded)

Two web hits reference a "‘958" patent but are not US 11,193,858:

• IPR2026-00268 (CRRC Meishan Co. Ltd. v. …) — Exhibit 1003 is captioned "11,885,358 File History." That is US 11,885,358, a different patent number (per the operating rule to read identifiers literally, I do not auto-correct this to 11,193,858). Docket: https://gaeflexstaging-dot-docketupdate.appspot.com/cases/PTAB/IPR2026-00268/CRRC_Meishan_Co._Ltd/02-20-2026-Petitioner/Exhibit-1003-Ex_1003___11,885,358_File_History/ — a rail-transportation petitioner, unrelated art.
• An IPR involving "the '958 Patent" with Bigbee/Nguyen lockstep-processor art and a Unified Patents ex parte reexamination — that is a to-this-day unidentified processor patent bearing the same three-digit shorthand. Not tissue planing. Source: ptacts.uspto.gov petition exhibits.
• LifeNet Health v. Tissue Regenix Woundcare, Inc. (E.D. Va. 1:17-cv-00533; transferred to W.D. Tex. 5:17-cv-01061) involved U.S. Pat. No. 6,569,200 and named Community Tissue Services as a defendant, not as plaintiff asserting the '858 patent. Not probative of '858 assertion or PTAB activity. Docket: https://www.courtlistener.com/docket/[6060453](/patent/6060453)/lifenet-health-v-tissue-regenix-woundcare-inc/

Strategic summary

Claim status. Because no AIA trial has ever been instituted, no claim of US 11,193,858 is canceled, and no claim has been adjudicated. All 20 claims stand as issued on 2021-12-07 — independent claims 1, 11, and 17, and dependents 2–10, 12–16, 18–20. The three independent claims cluster around three distinct inventions: (1) the sensor-gated "ready configuration" interlock (claims 1–10), (2) the two-hand-control dead-man requirement (claims 11–16), and (3) the blade-assembly/spacer cutting-depth architecture (claims 17–20). Any invalidity theory must address each cluster separately — they do not rise and fall together, and claim 17's spacer-groove limitation has no obvious counterpart in the sensor/hand-control claims.

Estoppel landscape. There is no § 315(e)(2) estoppel and no § 325(e)(2) estoppel against anyone, because no petitioner has ever reached a final written decision (or even institution). Nor are you bound by any prior petitioner's grounds under privity theories — the pool of potential privies is empty. Practically, that means every prior-art ground is available to you: § 102 and § 103 art in the skinning-machine field (the Google Patents "Citations (67)" list is dominated by Townsend Engineering meat-skinning patents spanning US 2,455,831 through US 4,996,742, plus Burn Treatment Skin Bank US 3,777,599 for split-thickness animal skin) is all fair game, as is § 112 written-description and enablement art on the "ready configuration" sensing language. Nothing about this patent has been narrowed by adverse PTAB holdings.

Pattern signals. No pattern exists yet: no repeat petitioner, no defensive aggregator (e.g., Unified Patents, RPX) in the chain, and no PTAB appeal by the patent owner because there has been nothing to appeal. The patent owner, Community Blood Center d.b.a. Community Tissue Services, is a nonprofit tissue bank rather than a serial litigant, and my search found no assertion campaign by CTS as plaintiff. One structural note: US 11,619,569 B2 is a divisional filed 2021-11-11 claiming the same 2018-05-01 priority and sharing the same specification. It is a separate patent with its own claim set and its own patent term; a challenge to '858 does nothing to it, and an IPR against '858 does not estop you from later challenging '569.

Recommended next steps

1. Say it plainly in any opinion letter: there is no PTAB record on this patent. Do not represent an absence of IPRs as "the patent is weak" — an untested patent is simply untested. Conversely, if you are defending a demand letter, do not concede the claims are "hardened by PTAB"; they have never been examined adversarially.

2. File first if you intend to file. With no prior petitioner, you face no § 325(d) "previously presented art" bar keyed to PTAB proceedings and no discretionary-denial argument built on "the same petitioner filed before." Consider a § 315(b) timing check against any served complaint — the one-year bar runs from service of a complaint alleging infringement of this patent, and a parallel pending district court case is the usual § 314(a) Fintiv discretionary-denial risk, though that practice has narrowed post-Commil/Director guidance.

3. Grounds to develop. Prioritize (a) the Townsend Engineering skinning-machine family for the blade/shoe/spacer claims (17–20); (b) machine-guarding and interlock art under § 103 for the "component sensor prohibits operation" claims (1–10), where the novelty likely resides in the application of a known safety-interlock concept rather than the interlock itself; and (c) printed publication or public-use art on the two-hand-control "hold-to-run" configuration (claims 11–16) — two-hand control is a mandatory OSHA-era industrial press standard and is a strong § 103 candidate. Consider § 112 for the functional "ready configuration"/"missing from the ready configuration" language and for the surrogate-adipose-layer discussion, which appears in the specification but not in the claims.

4. Monitor the family and the statute of limitations. Track US 11,619,569 B2 (divisional) and WO2019/213088A2 for prosecution-spinoff patents with broader claims. Flag "IPR2026-00268 / 11,885,358" in any internal docketing system as an unrelated patent so a human doesn't mis-index it against 11,193,858 — the numbers are one digit different and false-positive risk is high.

5. If a petition is filed after today's date, PTAB statutory timing controls: institution decision within 6 months of the § 314(b) PO preliminary response deadline, oral hearing at roughly the 8–9-month mark, and the Final Written Decision due within 12 months of institution (extendable up to 6 months for good cause under § 316(a)(11)). Track it at USPTO PTAB E2E (https://ptacts.uspto.gov) and the PTAB Decisions page.

I'll research the assignment record and ownership chain for US 11193858. Let me start with targeted searches.

Initial searches returned noise. Let me target the actual entities and the assignment records more precisely.

Inventors

Notes and unusual-pattern check:

• All three inventors appear together on the sibling application US 17/524,569 (issued as US11619569B2), confirming a stable internal R&D team rather than a hired inventor pool.
• No departures or inventor-side assignments could be identified within 12 months of the 2018-05-01 filing. The assignment was executed to the employer, not away from it, which is the normal course for a corporate/non-profit invention and not a fire-sale tell.
• Caution: the Justia assignee page for this family also shows Felicia C.T. Gooden as an inventor — but that is on a different Community Blood Center patent (graft-preparation/suturing system), not on US 11193858. Do not conflate them.

Original assignee

• Entity named on the issued patent: Community Blood Center (the assignment records and Google Patents use the form "Community Blood Center d.b.a Community Tissue Services").
• Line of business: Independent non-profit blood center and tissue bank; its tissue division (Community Tissue Services) recovers, processes and distributes human allograft skin, bone and soft-tissue grafts — i.e., a genuine operating entity that ships commercial product.
• Does it ship a product embodying the claims? Yes, in substance. The patent is a process-equipment patent (a tissue planing assembly used to produce split-thickness skin grafts). Community Blood Center / Community Tissue Services publicly celebrated producing its one-millionth tissue graft in 2022 and markets skin grafts processed with its proprietary methods. The patented assembly is internal tooling rather than a sold article, which is typical for tissue-bank process patents.
• Current status (as of this analysis): Operating. In 2023 the organization rebranded to "Solvita." On 2024-11-04/05 it sold its blood-collection operations to Versiti (now Versiti Blood Center of Ohio). Crucially, the sale expressly excluded the tissue-services business, which Solvita retained and continues to operate from Dayton and Kettering Research Park. The patent therefore sits with the continuing tissue-services non-profit. No bankruptcy, dissolution, or insolvency event was found.

Assignment timeline

The authoritative patent text records exactly one assignment, and it is the ordinary pre-issuance inventor→employer assignment. Google Patents legal events show:

• 2018-05-01 (executed) / recorded 2018-05-01 — Reel/Frame: not retrievable
  • Conveyance: Assignment of Assignors' Interest (inventor-to-assignee)
  • Assignor: HOSKINS, Robert; LUCOUS, Gregory S.; HUNTER, Shawn Aaron
  • Assignee: Community Blood Center d.b.a. Community Tissue Services (Dayton, OH)
  • Correspondent: Not determinable from the sources retrieved (the recording correspondent attorney/firm was not surfaced by the searches run).
  • Context: Standard employee invention assignment to the operating non-profit; no consideration-shifting or third-party transfer.

No post-issuance assignments of any kind were found. There is no record of the patent moving to an IP-holding LLC, no security interest, no merger conveyance, no license recordation, and no change-of-name recordation (the 2023 Community Blood Center → Solvita rebrand does not appear as a recorded assignment; the register still shows "Community Blood Center").

Related family activity (ownership-relevant, all same assignee):

• US 17/524,569 (divisional, filed 2021-11-11 → US11619569B2, granted 2023-04-04) — Community Blood Center.
• PCT/US2019/029925 (filed 2019-04-30 → WO2019213088A2/A3) — Community Blood Center.

Verification link: https://assignmentcenter.uspto.gov/ (search by patent number 11193858) — same underlying records as https://assignment.uspto.gov/patent/index.html.

Data-integrity flag: I could not obtain the specific reel/frame number or the correspondent of record from the searches performed, and I will not invent them. Everything above that has a specific number is drawn from the authoritative patent text / indexed legal events; the reel/frame and correspondent fields are marked "not retrievable." A direct assignment-center query (or a PEDS/ODP lookup of the assignment documents) is needed to populate those two fields.

Timeline diagram

timeline
    title Ownership of US 11193858
    2018 : Inventors assign to Community Blood Center
         : Application filed 2018-05-01
    2019 : PCT filed 2019-04-30
    2021 : Patent issued 2021-12-07
         : Divisional filed 2021-11-11
    2023 : CBC rebrands as Solvita
    2024 : Blood ops sold to Versiti
         : Tissue services and patent retained

NPE / troll-pattern signals

1. Shell-entity transfer — not present. The only recorded assignee is "Community Blood Center d.b.a. Community Tissue Services," a named operating non-profit with physical premises (349 S. Main St., Dayton, OH; 2900 College Dr., Kettering, OH). No "IP/Holdings/Ventures" LLC, no registered-agent address, and no single-purpose entity appears anywhere in the chain.
2. Known asserter in the chain — not present. Neither the assignee nor any recorded party matches Acacia, Marathon, IV, Wi-LAN/Conversant, Pendrell, Vringo, etc. No RPX/Unified high-frequency-plaintiff entity is involved.
3. Repeat correspondent across the chain — not present / unclear. There is only one link in the chain, and its correspondent was not retrievable; recurrence cannot be assessed and no NPE-linked attorney of record was identified.
4. Cascading transfers — not present. No chained LLC-to-LLC assignments; zero post-issuance conveyances in the record.
5. Pre-litigation transfer — not present. No infringement suit naming this patent was identified (consistent with the earlier litigation pass), so there is no pre-suit assignment window to evaluate.
6. Bankruptcy fire-sale — not present. No Chapter 7/11 for Community Blood Center/Solvita. The 2024 Versiti transaction was an asset sale of a going-concern blood operation, explicitly excluding tissue services and the associated IP.
7. Privateering — not present. No transfer to a third-party assertion vehicle; the non-profit retained its tissue portfolio.
8. Defensive aggregator — not present. Chain does not terminate at RPX, AST, LOT, Unified or OIN.

Verdict

Insufficient data — per the defined label ("only the original assignment"), which is literally the situation: the sole recorded conveyance is the 2018-05-01 inventor → Community Blood Center d.b.a. Community Tissue Services assignment, with no post-issuance records. That said, the affirmative finding is that all eight NPE/troll signals are absent: ownership has never left a genuine operating non-profit tissue bank that ships skin-graft product, the 2024 Versiti deal carved out and preserved the tissue-services IP, and there is no shell entity, no asserter, no defensive aggregator, and no assertion history. This is best characterized as a benign, non-asserting operating-company chain, not an NPE pattern — the "Insufficient data" label reflects the thinness of the public assignment record (one entry), not ambiguity about troll behavior. Verify at https://assignmentcenter.uspto.gov/ by searching patent number 11193858.

(Cross-reference flag: the earlier litigation section found no relevant suits; that is consistent with — not contradicted by — the ownership findings here.)

I'll research this patent and its cited prior art. Let me start with targeted searches.

Let me gather the full citation list and details on key references.

Prior-Art Analysis — US 11193858 B2

Flag before I begin

Two things you should know up front, per your operating rules:

1. Date conflict. The system header states the current date is 2026‑09‑29, while the task block states April 26, 2026. I cannot reconcile these from the sources; treat dates below as they appear in the records themselves.
2. Cross-reference conflict / null section. The "Previously generated sections" you supplied contain a heading called Litigation summary but no substantive content — only a description of search methodology. There is therefore nothing to build on or contradict there. My searches for US 11193858 surfaced no litigation; the only court document that appeared (Zimmer v. Exactech, S.D. Fla. 8:21‑cv‑00995) is unrelated to this patent. If a litigation section is expected, it is effectively empty and should be regenerated.

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1. Patent identification (verified against the authoritative text)

Source: https://patents.google.com/patent/US11193858/en and https://patents.justia.com/patent/[11193858](/patent/11193858)

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2. The cited art — what it actually is

On its face, US 11193858 cites 67 references. The dominant theme is industrial meat/fish skinning and derinding machinery, principally Townsend Engineering Company (Des Moines, IA) — the company that commercialized the "Townsend skinning principle" (sharp blade + tooth/gripping roll + pressure shoe). See Marel/Townsend product literature: https://marel.com/media/ztfltshu/sk15-330_auto_return_skinner.pdf.

This matters: the cited art is structural/mechanical, and it maps almost entirely onto independent claim 17 (the shoe/groove/blade-clamp/spacer blade assembly) and, to a lesser degree, claim 18. It does not map onto the sensor-based lockout of claim 1 or the two-hand-control interlock of claim 11 — those are the features that distinguish this patent from the cited art.

Reference table (US documents, from the Justia "Referenced Cited" list)

Also cited (confirmed from Google Patents): US 3184785 (Schmid & Wezel, rotary cutter, 1965), US 3324915 (Townsend, 1967), DE 1293636 B (MAJA/Schill, cutting device for bacon derinding machines), US 3703199 (Townsend, automatic blade control mechanism, 1972), US 3742841 (Townsend, fatting attachment, 1973), US 4433453 (Hormel, shoulder skinning device, 1984), and family members US 3844207 (Townsend, automatic blade control).

(I could not retrieve the complete 67‑item list — the authoritative text you supplied truncates at US 4996742, and the Justia page truncates at US 7338489. Items marked "unverified" are ones whose titles I could not confirm in search results; I decline to invent descriptions for them.)

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3. Anticipation mapping under 35 U.S.C. § 102

Anticipation requires a single reference disclosing every element of the claim, arranged as claimed. Below, I map the cited art to each independent claim.

Claim 1 — disassemblable components + component sensors + control-unit lockout

Elements: base frame; plurality of disassemblable components in a "ready configuration" supporting a tissue sample; sample conveyor; blade assembly; control unit; one or more component sensors signaling a missing component; control unit prohibits conveyor operation when a component is missing.

Assessment: no cited reference anticipates Claim 1. None of the 67 cited references discloses electronic component-presence sensing or a controller that disables a conveyor drive when a removable component is absent. The cited art is mechanical skinners with no such interlock. The closest analogues are mechanical safety guards (US 3898923; US 3949661), which are structurally and functionally different from a sensed "ready configuration" lockout. Claim 1 appears to rest on this feature.

Claim 11 — dual hand controls (two-hand / "deadman" interlock)

Elements: base frame; conveyor; blade assembly; control unit; first and second hand controls, with logic to run the conveyor only when both are activated.

Assessment: no cited reference anticipates Claim 11 on the present record. The cited safety art (US 3898923 "safety table"; US 3949661 "safety means"; US 4071923 "guard ring … prevents the actuating lever from being depressed") constrains operator access/actuation but does not disclose two independent, concurrently-held hand controls gating a motor controller. Anticipation would require a reference disclosing two-hand control logic — I did not find one among the cited art.

Claim 17 — blade assembly: shoe with groove, blade on top surface, blade clamp, spacers to set cutting depth

This is where the cited art bites hardest. Independent claim 17 is the claim most exposed.

Assessment: several cited references disclose a blade mounted on a shoe and held by a clamp (US 5011454, US 4606093, US 4071923), and at least one (US 3703199/US 3844207) discloses adjusting cutting depth by moving the blade relative to the gripping roll. However, on the sources I retrieved, none is confirmed to disclose "one or more spacers positionable within [a shoe] groove adjacent to the blade to adjust a cutting depth" — the specific groove-and-insertable-spacer architecture recited in claim 17. That element is what distinguishes claim 17 from the meat-skinning art. So I would rate the cited art as creating a § 103 obviousness risk to claim 17, not a clean § 102 anticipation.

Claim 18 (dep. of 17) — gripping roller positioned relative to cutting edge; cutting-edge position adjustable relative to the roller

US 3703199 and US 3844207 ("Automatic blade control mechanism for meat skinning machines") are the most direct potential § 102 references here, since they expressly concern adjusting the blade/cutting edge relative to the gripping (tooth) roll.

Claims 19–20 (dep. of 17) — spacer behind the blade in the longitudinal direction; each spacer ↔ a skin-graft thickness

No cited reference is confirmed to disclose either. US 3777599 (split-thickness animal skin process) is field-adjacent (thickness of split-thickness skin) but is a process for skin, not a spacer-in-groove depth fixture; it does not anticipate claims 19–20.

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4. References that are NOT prior art to this patent

Do not treat these as § 102 art — they postdate the 2018‑05‑01 priority date or are the patent's own family:

• US 11369409 B2 — Medline Industries, "System and method for fluid ingress control for a skin grafting system," priority 2019‑10‑03. It is a family-citing document (forward citation), later than US 11193858's priority date.
• US 12616215 B2 — Meyn Food Processing, "Dismountable poultry processing knife and a mounting frame," priority 2021‑10‑18. Forward citation (cited-by), not prior art.
• WO 2019213088 A2 — the PCT counterpart of this very application.
• US 11619569 B2 / US 17/524,569 — the divisional of this patent.

Also surfaced in searching but not cited on the patent and its status as art is unverified against this record: LifeCell Corporation's "vacuum platen tissue planing apparatus" (e.g., AU 2019280059, priority to 2014/2019) — see the Australian Official Journal entry at pericles.ipaustralia.gov.au. If you are looking for non-cited, contemporaneous tissue-planing art, that family (LifeCell/Fry & Howe-Smith) is a better lead than anything on the face of the patent.

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5. Bottom line

1. Most relevant cited prior art = the Townsend meat-skinning line, especially US 5011454, US 4606093, US 4811459, US 4071923, US 3703199/US 3844207, and DE 1293636 B. These supply the shoe/blade/clamp/adjustable-depth concepts of independent claim 17 and dependent claim 18.
2. No cited reference anticipates claims 1 or 11. The sensor-based "ready configuration" lockout (claim 1) and the dual-hand-control interlock (claim 11) are not disclosed by the mechanical skinning art cited.
3. Claim 17 is the vulnerable claim — not by clean § 102 anticipation on the retrieved record, but by § 103 over the Townsend shoe/blade/clamp/depth-adjust art. The specific spacer-in-shoe-groove limitation is what I could not find anticipated.
4. Caveats: (a) the full 67-item citation list was truncated in the sources I could reach, so several later references (US 5083973, 5122091, 5350334, 5481466, 5558573, 5921980, 5934164, 6066035, 6213863, 6299523, 6434978, 6440143, 6553886, 6589108, 6659856, 6698255, 6733530, 6856852, 7128642, 7241213, 7338489) remain unverified — I have not characterized them and cannot assert what they disclose; (b) several searches returned step-limit errors, so this is not an exhaustive claim-by-claim validity opinion.

Sources: https://patents.google.com/patent/US11193858/en · https://patents.justia.com/patent/11193858 · https://www.freepatentsonline.com/y2019/0339169.html · https://patents.google.com/patent/US5011454A/en · https://patentimages.storage.googleapis.com/4a/5d/68/65c39f11299690/US4606093.pdf · https://patents.justia.com/patent/4071923 · https://marel.com/media/ztfltshu/sk15-330_auto_return_skinner.pdf

I'll ground the obviousness analysis with targeted searches on the key secondary references and the standards/safety-art landscape, then map combinations claim-by-claim.

Strong grounding so far. Let me verify two more anchors — the cited Townsend "safety means" switch reference and the general machine-guard interlock art.

Obviousness Analysis Under 35 U.S.C. § 103 — US 11,193,858 B2

"Tissue planing assemblies and methods" (Community Blood Center d.b.a. Community Tissue Services)

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0. Scope, inputs, and flags before I start

This analysis builds directly on the Prior Art section already generated for this matter and uses only the references it identified plus what I could verify in follow‑up searching. I do not repeat that section's citation tables.

Four flags, per the operating rules and the "flag contradictions" instruction:

1. I partially disagree with the earlier Prior Art section — and the discrepancy matters. That section characterized the cited Townsend safety art as merely constraining "operator access/actuation" and concluded that "no cited reference discloses electronic component‑presence sensing or a controller that disables a conveyor drive when a removable component is absent." The first half of that is true. The second half understates the art. The cited US 3,949,661 (Townsend, "Safety means for a skinning and/or slashing machine") discloses precisely a component‑position switch that shuts the machine off. Verified text: "Safety bar 98 would be in the position illustrated in FIG. 4 so that the switch means 104 would be closed and the support arms 32 and 34 would also be in their operating position so the switch means 44 would also be closed. The power source for the machine would be actuated…" and "If the slashing apparatus pivotally moves upwardly with respect to the machine, notch 38 on shaft 36 moves out of engagement with the roller 40 thereby causing the switch means 44 to deactivate the power source." (https://patentimages.storage.googleapis.com/4c/4a/f6/e7cabfe837e8e9/US3949661.pdf · https://patents.google.com/patent/US3949661). That is a kinematic interlock keyed to a removable/movable subassembly, and it is the single closest piece of art to independent claim 1. I treat the earlier section's "claim 1 appears to rest on this feature" conclusion as too favorable to the patent.

2. Date conflict, unresolved: system header says 2026‑09‑29; the task block says April 26, 2026. I cannot reconcile them; dates below are stated as they appear in the records.

3. "Hold down bar" (claim 9) vs. "hold down roller 172" (spec) — carried forward from the earlier section as an internal discrepancy.

4. § 325(d) relevance — new art vs. cited art. Several references I rely on below are NOT on the face of US 11,193,858: US 6,589,108 (Townsend, tapered blade and holder), US 4,965,909 / US 5,272,946 / EP 0 362 937 B1 (electronic safety control systems for meat skinners), US 3,513,893 and US 3,559,707 (Townsend‑family skinners with sensor/valve control and in‑shoe blade adjustment), and the LifeCell vacuum‑platen family (US 9,594,004; US 10,495,548). The fact that US 3,949,661 was cited and considered by the examiner is a double‑edged sword: it is strong art, but a petition resting on it alone invites discretionary denial under § 325(d). Frame any challenge around materially new combinations using the uncited references.

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1. Legal framework and level of ordinary skill

Framework applied (Graham v. John Deere; KSR Int'l v. Teleflex):

• § 102 requires a single reference disclosing every element arranged as claimed. As the earlier section found, there is no clean § 102 hit on claims 1 or 11 on the retrieved record, and none on claim 17's groove‑and‑spacer limitation.
• § 103 permits combination of references, or a single reference plus the knowledge of a PHOSITA, where the references are analogous and there is an articulated reason to combine. KSR supplies the recognized rationales I invoke: (i) known technique; (ii) simple substitution of one known element for another; (iii) use of a known technique to improve a similar device in the same way; (iv) predictable variation; (v) "obvious to try" with a finite number of identified, predictable solutions; (vi) design incentives and market forces. KSR also authorizes reliance on standards and industry practice as evidence of what a PHOSITA would have done.

Proposed PHOSITA: a person with a bachelor's degree in mechanical or biomedical engineering (or equivalent), plus 2–5 years designing tissue‑processing/skinning capital equipment or comparable medical‑device manufacturing machinery, who is familiar with (a) skinning/planing machine architecture (frame, feed tray/conveyor, toothed or toothed‑roll gripping conveyor, shoe‑mounted blade and clamp, hold‑down roll, exit tray), (b) tissue‑bank processing requirements (split‑thickness skin, ~0.3–0.65 mm; single‑use‑between‑donors sanitation), and (c) U.S. industrial machine‑guarding standards — OSHA 29 CFR 1910.211–.217 and ANSI B11.1.

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2. Analogous‑art determination (threshold to every combination below)

Under the two‑prong test (field of endeavor / reasonably pertinent to the problem), the Townsend meat‑, poultry‑ and fish‑skinning corpus is analogous:

• Field: the structural problem is the same — separating a thin surface layer from a thicker substrate using a toothed pulling roll, a fixed blade in a shoe/clamp, and a hold‑down element.
• Reasonably pertinent: the bridging is supplied by the patent's own cited reference US 3,777,599 (Burn Treatment Skin Bank, "Process for producing split‑thickness animal skin for protecting flayed human tissue," 1973) — i.e., the industry already applied this machine architecture to produce split‑thickness skin for human wound coverage. The '858 patent's own background cites this lineage.

The LifeCell "Vacuum platen tissue planing apparatus" family (US 9,594,004 B2, filed 2014‑12‑19, priority 2014‑01‑10; continuation US 10,495,548 B2; AU 2014376197B2; published 2017‑07‑27 as US 2017/0212014 A1) is the most analogous art of all — same field (human/animal tissue planing to separate dermis from subcutaneous fat for graft products), pre‑2018, and squarely within § 102(a)(2)/(a)(1). Its disclosures are directly useful even though its architecture is inverted (stationary tissue on a vacuum platen; blade travels):

• "it is necessary to isolate the dermis from underlying tissues, including subcutaneous fat… it is important that the dermis remains intact and not damaged by the separation process" (states the problem).
• "The platen surface can be attached to an adjustable frame assembly. The frame assembly can be positionable at an adjustable angle with respect to a supporting surface" (angled support surface — claim 5/6).
• "a constant frame of reference for cutting" and stainless‑steel/rigid construction (material/cleanability motivations — the '858 spec's electro‑polished stainless rationale).
• https://patents.google.com/patent/US10495548 · https://patentimages.storage.googleapis.com/f2/26/b3/9f0a586d5bfc50/US9594004.pdf

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3. Combination I — Claims 1 and 2–10 (sensor‑gated "ready configuration" interlock)

3.1 Primary combination

US 3,949,661 (Townsend) + US 5,011,454 (Townsend) + US 3,777,599 (Burn Treatment Skin Bank), optionally + US 4,071,923 and the LifeCell family, plus the admitted common knowledge of machine‑guard interlocks (OSHA 29 CFR 1910.217 interlocking barrier guards).

3.2 Why a PHOSITA would have combined these

1. Design incentive / market force. Between‑donor sanitation requires removing and reinstalling the trays and hold‑down roller. Each removal/reinstall is an opportunity to mis‑seat or omit a component. The two consequences are both severe and both known in this exact field: (a) product safety/contamination and yield loss (the patent's own stated concerns), and (b) blade exposure — the blade assembly is an unguarded cutting edge with a driven roller behind it. These are the classic conditions that drive machine builders to interlock.
2. Known technique. Interlocking a removable guard/component with the drive is one of the oldest, most standardized techniques in machine design; OSHA 29 CFR 1910.217 requires interlocking barrier guards to be "interlocked with the press clutch control so the clutch cannot be activated unless the guard" is properly positioned (https://www.osha.gov/dte/grant_materials/fy09/sh-18796-09/sheetmetal.pdf). The '858 patent applies this established guarding principle to a new machine class — the classic "known technique to improve a similar device in the same way."
3. Simple substitution. US 3,949,661 already discloses a mechanical plunger/roller switch doing exactly this job in a skinning machine. Replacing that plunger switch with a magnetic in‑position switch (as the '858 spec itself specifies) is a substitution of one known sensing element for another, with a predictable result (a signal instead of a contact closure). No new function, no new result. KSR forecloses patentability of that substitution.
4. The bridging reference. US 3,776,599 supplies the specific reason to look at this machine class when the output is human split‑thickness skin — closing any "non‑analogous art" argument that the meat‑skinning interlocks are remote from the tissue‑bank problem.
5. Reasonable expectation of success. Switch‑to‑controller lockout logic is deterministic; nothing in the '858 spec suggests unpredictable behavior in the claimed sub‑combination.

3.3 Dependent claims 2–10

Strength assessment for Combination I: strong § 103 on claim 1; near‑§ 102 on claims 8, 9, 18. The examiner considered US 3,949,661 but apparently did not appreciate it as a component‑interlock teaching, which is precisely the gap a well‑reasoned petition could target — subject to the § 325(d) caution in flag #4.

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4. Combination II — Claims 11 and 12–16 (two‑hand "hold‑to‑run" control)

4.1 Primary combination

The OSHA/ANSI two‑hand‑control standard (29 CFR 1910.217(b)(7)(v) and (c)(3)(vii); ANSI B11.1) + US 4,965,909 / US 5,272,946 / EP 0 362 937 B1 (electronic safety control for a meat skinning machine) + US 5,011,454 (machine architecture).

4.2 Why this is a strong § 103 case

The distinguishing limitation of claim 11 is the requirement that the machine run "only when both the first hand control and the second hand control are activated." That requirement is not merely a known technique — it was mandatory in U.S. industry decades before 2018, and it is written almost verbatim in the standard:

• 29 CFR 1910.217(b)(7)(v)(a): each hand control "must be… arranged by design, construction, and/or separation so that the concurrent use of both hands is required to trip the press."
• 1910.217(b)(7)(v)(b): the control system "must be designed to permit an adjustment which requires concurrent pressure from both hands during the die closing portion of the stroke."
• 1910.217(b)(7)(v)(d): "the release of all hand controls before an interrupted stroke can be resumed."
• (c)(3)(vii)(a): "The removal of a hand from any control button will stop the slide."
• https://www.law.cornell.edu/cfr/text/29/1910.217 · https://osha.prod.pace.dol.gov/etools/machine-guarding/presses/two-hand-controls · https://osha.prod.pace.dol.gov/laws-regs/standardinterpretations/1992-12-21-1

The '858 spec's own added limitation — the controls "may be biased to an unactivated position, such that continuous and concurrent manipulation… is needed throughout processing" — is the anti‑tie‑down / hold‑to‑run feature that OSHA's standard and its interpretations expressly require (an OSHA interpretation states that if a button "is tied down, the power press would be inoperable… If one of the buttons is released during the continuous run, the control circuitry must be such that the press will stop."). That is legal‑standard language, and it is the best possible evidence of what a PHOSITA would have done.

The secondary references supply the machine‑specific link:

• US 4,965,909 / US 5,272,946 / EP 0 362 937 B1 disclose a meat skinning machine in which an electronic safety control circuit 50 gates drive motor 7, requires operator‑input conditions before the drive is enabled, and disengages the drive instantaneously on a sensed dangerous condition. This is the "control unit executes logic to operate the sample conveyor only when [condition]" architecture of claim 11, already applied to a skinner.
• US 3,949,661 shows a normally‑closed switch electrically connected to deactivate the skinner power source — the same "condition‑gated drive" concept.
• US 3,513,893 shows a skinning machine with "Switch 120… imposed in line 116 to control the machine" and a foot switch 23 controlling drive motor 7.

Motivation, articulated: (1) Operator hands are near an exposed blade and a driven toothed roll — the classic point‑of‑operation hazard; the recognized safeguard is to occupy both hands and stop the drive if either is released. (2) Compliance with OSHA/ANSI machine‑guarding standards is a legal and commercial design driver. (3) The technique is known and its result predictable — a two‑hand control either gates the drive or it does not; nothing unpredictable happens when applied to a tissue planer.

4.3 Dependent claims 12–16

Strength assessment: very strong § 103 on claim 11. Two‑hand control is a statutory requirement, not an invention. Claims 12–14 are near‑anticipation; claims 15–16 rise and fall with the claim‑1 interlock concept.

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5. Combination III — Claims 17 and 18–20 (shoe‑groove / spacer blade assembly)

5.1 Primary combination

US 5,011,454 (Townsend) + US 3,703,199 / US 3,844,207 (Townsend, "Automatic blade control mechanism") + US 3,559,707 (Townsend family; in‑shoe blade adjustment screws), optionally + US 6,589,108 (Townsend tapered blade and holder; uncited), US 4,606,093, US 4,811,459, US 4,071,923, DE 1293636 B, and the microtome/shimming knowledge reflected in the patent's own G01N 1/06 classification.

5.2 Why a PHOSITA would have combined these

1. Design incentive. The '858 patent's own field demands a reproducible graft thickness (S/T skin ~0.3–0.65 mm) — a tolerance that cannot be hit by eyeballing a continuously adjustable screw. The prior art already taught changing blade position to change depth (US 3,703,199/US 3,844,207 — automatic blade control; US 3,559,707 — adjusting screws 78 in the shoe). The remaining problem — making a selected depth repeatable and quickly re‑selectable — is a classic standardization problem.
2. Known technique = indexed shims/spacers. Replacing a continuously adjustable element (screw, wedge, cam) with discrete indexed spacers/shims to set a fixed position is one of the oldest techniques in precision machine design, and is the defining technique of the microtome art into which this patent was classified (G01N 1/06 — microtomes set section thickness with spacers/feed increments). KSR treats such substitution as predictable variation.
3. Use of the existing groove. The shoe of the '858 claim already has a groove (in the spec, for the clamp fastener and for fluid drainage). Placing the spacer in that existing groove, "adjacent to the blade," is an obvious use of an existing feature — no new structure is created.
4. Commercial corroboration of the motivation. The Townsend/Marel SK 15‑350 "Auto ThinAdjust" skinner is marketed on the strength of "Four programmable button settings for unique skinning thicknesses" and the ability to "adjust skinning thickness while the machine is running" (https://cms.jbtmarel.com/en/products/townsend-sk-15-350-autoshoe-adjust-derinding-skinner/). That is independent evidence that the industry was actively engineering discrete, pre‑set cutting depths rather than free‑form adjustment. (Caveat: I could not date this product literature to confirm it predates the 2018 filing; treat it as corroborative motivation, not as § 102 art.)
5. Reasonable expectation of success. A spacer of a known thickness places the blade edge at a predictable offset; the result follows mechanically.

5.3 Dependent claims 18–20

Strength assessment: § 103 is strong on claim 17 and approaches § 102 on claim 18. The earlier section's conclusion that "claim 17 is the vulnerable claim… by § 103 over the Townsend shoe/blade/clamp/depth‑adjust art" is supported, and I would add US 3,559,707's in‑shoe adjusting screws and US 6,589,108's wedge as tightening the motivation on the "spacer to adjust cutting depth" limitation.

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6. Omnibus combination and claim chart

The single most efficient attack packages all three clusters into one § 103 case:

US 5,011,454 (the skinner: frame, toothed gripping roll, shoe‑mounted blade and clamp, feed/exit surfaces, product held up and over the blade)

• US 3,949,661 (component‑position switch electrically connected to deactivate the machine's power source — the interlock concept; and multiple series switches)
• US 4,965,909 / US 5,272,946 / EP 0 362 937 B1 (electronic control circuit gating a skinner's drive motor)
• OSHA 29 CFR 1910.217(b)(7)(v)/(c)(3)(vii) and ANSI B11.1 (two‑hand, anti‑tie‑down control; interlocked guards)
• US 3,703,199 / US 3,844,207 and US 3,559,707 (blade‑position adjustment within the shoe; blade position relative to the gripping roll)
• US 3,777,599 (the tissue‑bank/split‑thickness‑skin application; the bridging analogous‑art reference)
• optionally LifeCell US 9,594,004 / US 10,495,548 (human tissue planing; adjustable‑angle frame; cleanliness/damage‑avoidance problem statement)

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7. Graham factor 4 — secondary considerations

There is no evidence on the present record of objective indicia that would rebut these combinations:

• No unexpected results. The '858 specification asserts improved outcome (wider grafts, consistent thicknesses, fewer mis‑assembly incidents) but attributes them to applying a known conveyorized‑skinner architecture to human tissue laid epidermis‑side‑down. Nothing in the spec reports an unpredictable property arising from the sensor lockout, the two‑hand control, or the spacer geometry. Improvement over a manual dermatome is not improvement over the claimed combination of references.
• No nexus shown. Any commercial success of Community Tissue Services' grafts flows from the processing method and tissue quality, not demonstrably from the claimed interlock/hand‑control/spacer structure. There is no sales/failure‑of‑others data in the record tying the claimed features to success.
• No copying/licensing evidence was surfaced in the earlier assignment and litigation sections (no suit, no license recordation, no post‑issuance assignment).
• Industry skepticism/teaching away: none identified. If anything, the art and OSHA standards teach toward these features.

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8. Where the patent still has room — and the strategic caveats

I should be candid about the limits of the above:

1. Claim 1's "plurality" + per‑component sensors + "ready configuration." US 3,949,661 senses one or two movable subassemblies (support arms and safety bar) on a meat skinner. To reach claim 1 you must combine it with a plural‑removable‑tray tissue machine and argue obviousness in adding a dedicated sensor for each of several trays. That is a strong but not airtight § 103 position; a patent owner will argue the claims capture a specific multi‑component tissue‑handling architecture the art does not. The § 325(d) overlay (US 3,949,661 was cited and considered) makes this the highest‑friction ground at the PTAB unless it is presented as a materially new combination with uncited art.
2. Claim 11 stands or falls on "only when both… are activated." The owner's best argument is that the prior art meat‑skinner safety systems (US 4,965,909) used glove/contact sensing and foot switches, not two hand controls. The answer is the OSHA standard, which makes two‑hand control a legal requirement for point‑of‑operation safeguarding and thus the presumptive design choice — but expect a fight over whether a tissue planer is "the same problem" as a power press (the analogous‑art argument in § 2 is the answer, aided by US 3,777,599 and the LifeCell art).
3. Claim 17's spacing limitation is the one item I could not find expressly disclosed. No retrieved reference shows "one or more spacers positionable within [a shoe] groove adjacent the blade." The case is therefore § 103 by combination (in‑shoe adjustment + shimming/standardization motivation), not § 102. The US 6,589,108 wedge and US 3,559,707 adjusting screws 78 in shoe 70 are the best closers, and both are uncited — good for § 325(d).
4. Do not over‑read the "Citations (67)" list. The earlier section correctly flagged that the list was truncated in the sources; several items (US 5,083,973, US 5,122,091, US 5,350,334, US 5,481,466, US 5,558,573, US 5,921,980, US 5,934,164, US 6,066,035, US 6,213,863, US 6,299,523, US 6,434,978, US 6,440,143, US 6,553,886, US 6,589,108, US 6,659,856, US 6,698,255, US 6,733,530, US 6,856,852, US 7,128,642, US 7,241,213, US 7,338,489) remain uncharacterized. Note in particular that US 6,589,108 is on the face of the patent's citation list even though the earlier section treated it as uncited — verify this before relying on the § 325(d) "new art" point; my sources were split on it.
5. Forward references are not prior art. US 11,369,409 B2 (Medline, priority 2019‑10‑03) and US 12,616,215 B2 (Meyn, priority 2021‑10‑18) postdate the 2018‑05‑01 priority date and cannot be used for § 102/§ 103. WO 2019/213088 A2 and US 11,619,569 B2 are the patent's own family. Do not cite them as art.
6. Identifier hygiene. The unrelated US 11,885,358 (IPR2026‑00268 exhibit) must not be conflated with US 11,193,858 — carried forward from the earlier sections.

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9. Bottom line

• Claim 11 is the most fragile claim in the patent. It claims the two‑hand, hold‑to‑run control — a statutory OSHA safeguard (29 CFR 1910.217(b)(7)(v), (c)(3)(vii)) that predates the filing by nearly half a century, and which the uncited skinner‑specific safety‑control art (US 4,965,909 / US 5,272,946 / EP 0 362 937 B1) shows how to implement in an electronically controlled skinning machine. A § 103 rejection/validity attack here should be straightforward.
• Claim 18 is the next most vulnerable and borders on § 102 over the automatic blade‑control Townsend art (US 3,703,199 / US 3,844,207), which expressly adjusts the blade/cutting edge relative to the gripping roll.
• Claim 1 is vulnerable to a well‑built § 103 combination anchored on US 3,949,661 (component‑position switch that deactivates the skinner's power) + US 5,011,454 (machine architecture) + US 4,965,909 (electronic drive lockout) + US 3,777,599 / LifeCell (tissue‑bank application and motivation), with the mechanical‑to‑magnetic in‑position switch swap supplying the KSR substitution rationale. The § 325(d) overlay and the "plural, individually sensed, sample‑supporting trays" wording are the patent owner's realistic defenses.
• Claim 17 is a genuine § 103 case, not a § 102 case. The shoe/blade/clamp sub‑combination is squarely in the Townsend art (US 5,011,454, US 4,606,093, US 4,811,459, US 4,071,923); the depth‑adjustment concept is in US 3,703,199/US 3,559,707; and the spacer‑in‑the‑groove refinement is the predictable application of indexed‑shim standardization with a strong industry motivation (reproducible graft thickness; Townsend's own "Auto ThinAdjust" programmable skinning thicknesses).
• Best single package: US 5,011,454 + US 3,949,661 + US 4,965,909 (or US 5,272,946) + US 3,703,199/US 3,844,207 + US 3,559,707 + US 3,777,599, plus the OSHA two‑hand‑control standard for claim 11 — with the uncited references (US 6,589,108, US 4,965,909, US 3,559,707, US 3,513,893, LifeCell) leading the argument to minimize § 325(d) risk.