US 11576764

Summary of U.S. Patent No. 11,576,764

Note on searching: Direct USPTO/CAFC database queries returned no machine-readable results through the available tools for this specific number. The only litigation-related material surfaced (W.D. Mich. Case No. 1:24-cv-00954, Solmetex v. Ascentcare, and associated IPR petitions) concerns sibling patents in the same family (e.g., 11,589,969; 11,589,970; 11,744,686; 11,826,217; 12,011,329) — I found no authoritative evidence of a CAFC 2026 appeal docket specifically listing patent 11,576,764. The bibliographic details below come from the Google Patents record provided in the prompt, which I treat as authoritative for this patent's text.

Bibliographic data (from the patent record)

• Patent number / kind code: US 11,576,764 B2
• Title: Intraoral device with stability bar
• Inventors: Thien Nguyen; Tam Thanh Pham
• Assignee (original): Solmetex LLC (application filed by Solmetex LLC; assignment recorded to Incept, Inc. on 2014-03-27; later to DryShield, LLC in 2017; back to Solmetex, LLC in 2022). Google's current-assignee field lists both Incept Inc. and Solmetex LLC.
• Application / filing date: US 14/228,054, filed March 27, 2014
• Issue (grant) date: February 14, 2023
• Earliest priority date: December 7, 2012 (provisional 61/734,939); the application is a continuation of US 14/100,323 (issued as US 8,911,232 B2)
• Status: Active; anticipated expiration 2033-12-09 (with patent-term considerations)
• Abstract: A dental mouthpiece attachable to a high-suction dental adapter for chair-side, hands-free suction and isolation, comprising a main body portion, a cheek retractor portion, and a suction connector portion — preferably molded in one piece by injection molding from a flexible, translucent, high-heat-resistant, autoclavable material such as silicone, making the mouthpiece reusable.

The invention in plain language

The device is a flexible, one-piece (or multi-part, with a detachable mouth prop) dental isolation/suction mouthpiece. Its main body is a hollow pocket having two opposing walls (an anterior/front-facing wall and a posterior/back-facing wall) connected by a connector wall, shaped wider at one end and narrowing into a rectangular region at the other end. Perforations/mesh admit saliva, water, and debris into the interior, which is connected to a suction/vacuum source through a suction connector portion. Two internal structural features are central: (1) a wave-shaped bridge structure on the interior of one wall whose crests contact the opposite wall to keep the walls from collapsing under vacuum while troughs leave open channels for fluid flow, and (2) an elongated stability bar running along the longitudinal axis into the rectangular portion to stiffen/shape the region that wraps around the most posterior tooth. A cheek retractor at the second end presses the cheek away from the teeth.

Independent claims (2 of 17 claims are independent: claims 1 and 16)

Claim 1 — A mouthpiece with:

• a main body portion having a first end wider than a rectangular portion at a second end, the main body including a pocket enclosing an interior space;
• a first wall defined by an exterior edge, extending from the first end to the second end and wider at the first end;
• a second wall spaced from the first wall, having a corresponding edge shape, also wider at the first end, and itself comprising:
  • an elongated stability bar lying in the interior space between the two walls' interior surfaces, extending along the longitudinal axis into the rectangular portion, and molded in one piece with the second wall; and
  • a bridge structure of multiple protrusions integral with and protruding from the second wall's interior surface, substantially spanning the distance to the first wall but not attached to the first wall, formed in a wave shape with crests and troughs;
• a connector wall joining the first and second walls; and
• a cheek retractor connected to the second end of the main body.

Claim 16 — A dental mouthpiece with essentially the same structure as claim 1, with the stability bar further characterized as reinforcing a thickness of material along the longitudinal axis (claims 17 depends on claim 16).

Claims 2–15 depend from claim 1 and add, e.g., the cheek retractor's laterally extending pressure-applying surface (2), the rectangular portion being narrower than the cheek retractor (3), the stability bar reinforcing the rectangular portion's resilience (4), spaced contact points on the bridge protrusions (5), a suction connector portion coupling the interior space to a vacuum source (6), one-piece injection molding (7), flexible/translucent/autoclavable silicone material (8), differing wall thicknesses (9), and a detachable mouth prop with bite block and strap features including flush-fit notched connector surfaces (10–15).

Uncertainty flags

• I could not verify any CAFC 2026 docket entry for patent 11,576,764 specifically; the Darts-IP litigation indicator on the Google Patents page shows a "first worldwide family litigation" flag, and the family is involved in the W.D. Mich. case noted above, but that docket material references sibling patents — not this one — in the passages retrieved.
• Assignment/ownership history is complex (Solmetex → Incept → DryShield → Solmetex, with Midcap Financial Trust security interests); current beneficial ownership should be confirmed against USPTO assignment records if precision is needed.

I'll search for litigation involving US Patent 11,576,764. Let me run several targeted searches.

The first search surfaced a PTAB document referencing the '764 patent in Eastern District of Texas lawsuits involving TSMC and UMC. Let me dig deeper to identify the parties and case details.

I was able to complete only a limited set of searches before hitting the tool-call limit, so my answer below reflects what could be verified — and what could not.

Direct answer

Based on the searches I could run, I did not find any confirmed, verified district-court litigation specifically naming US Patent 11,576,764 in the conventional litigation databases or news results I could access. I cannot, with high confidence, identify a plaintiff/defendant/case-number set that is confirmed to involve this exact patent.

What the searches did surface (with important caveats)

1. PTAB document referencing a "'764 patent" in EDTX litigation (unverified as this patent).
   A USPTO PTAB petition document (ptacts.uspto.gov) states that a patent owner filed suit:

   • Against TSMC in the Eastern District of Texas on August 1, 2024 ("TSMC Lawsuit"), and
   • Against UMC on September 6, 2024 ("UMC Lawsuit"),
   • That both lawsuits involve "the same seven patents, including the '764 patent,"
   • Assigned to Judge Rodney Gilstrap and consolidated for pretrial purposes,
   • With a claim-construction hearing scheduled for December 18, 2025, and jury trial set for June 22, 2026.

   Caveat: The snippet only refers to "the '764 patent" and never shows the full number. The parties (TSMC and UMC are semiconductor manufacturers) are inconsistent with US 11,576,764, which is a dental/suction mouthpiece patent owned by the Solmetex/DryShield corporate chain. This strongly suggests the PTAB document likely concerns a different patent whose number ends in '764 (e.g., a semiconductor-patent dispute), rather than US 11,576,764. I did not have enough search steps to confirm or refute this, and per your instruction not to return results for similar numbers, I am flagging this rather than asserting it as litigation for this patent.

2. Google Patents "family has litigation" flag.
   The Google Patents page for US 11,576,764 itself displays a "Family has litigation" indicator with a Darts-IP link for family ID 50881306. This indicates that some member of the patent family (which includes related applications such as US 11,589,969, US 11,589,970, US 9,788,924, and US 11,744,686) has been involved in litigation, but the flag does not confirm that this specific patent, US 11,576,764, is the one asserted.

Recommended next steps (since I could not verify further)

To definitively answer your question, I would need to check:

• PACER / EDXT docket for Solmetex LLC or DryShield LLC as plaintiff (the '764 patent's current assignee per its file history) — I found no docket entries tying Solmetex/DryShield to the TSMC/UMC suits.
• Unified Patents litigation portal and Darts-IP (family 50881306) to identify which family member is in suit.

Bottom line: As of this search, I have no confirmed litigation to report for US 11,576,764 specifically. The only hit referencing a "'764 patent" (EDTX, TSMC/UMC, Judge Gilstrap) appears contextually to concern a different patent, and I could not verify it before reaching my search limit. I'd be glad to run the additional PACER/Unified Patents/Darts-IP searches if you can lift the step limit.

Proceedings overview

Per the USPTO Open Data Portal (ODP) structured block included with this request, there are zero (0) AIA trial proceedings on file for U.S. Patent 11,576,764 as of the most recent ingest. Web searching did not surface any IPR/PGR/CBM petition naming the '764 patent as the challenged patent — the closest hits are a 2025 wave of Ascentcare Dental Products v. Solmetex IPRs directed at sibling patents in the same family (see flags below), not at the '764 itself. Defensive bottom line: the '764 patent has never been challenged at the PTAB — all 17 claims remain fully in force and untested in AIA trial, but the family-wide attack pattern signals that a petition on this exact patent may be forthcoming.

Individual proceedings

No proceedings against US 11,576,764 on file

• Type: N/A
• Filed: N/A
• Status: No AIA trial proceeding (IPR, PGR, or CBM) has been filed against U.S. Patent 11,576,764, per the ODP data provided and per web searching conducted 2026-09-07.
• Judge panel: N/A
• Petition grounds: N/A
• Institution decision: N/A
• Final Written Decision: N/A
• Settlement / termination: N/A
• Appeal: N/A
• Defensive value: The absence of a PTAB challenge is a double-edged sword. It means no prior-art ground has been adjudicated — so a defendant cannot rely on any PTAB estoppel or canceled-claim shortcut. But it also means the patent is not "hardened" by a petitioner's failed attempt; every § 102/§ 103 ground remains available to a future petitioner (subject only to the one-year IPR bar from service of a complaint, 35 U.S.C. § 315(b)).

Flagged web-search findings — proceedings on family-member patents (NOT this one)

Web search surfaced a coordinated 2025 petition campaign by Ascentcare Dental Products, Inc. v. Solmetex, LLC that does not name the '764 patent but does target near-identical patents from the same December 2012 priority family. I am flagging these because they are highly probative of what a future '764 petition would look like — but I could not confirm any of them challenges the '764, and I have not listed them as proceedings on this patent:

• IPR2025-01057 — Ascentcare Dental Products v. Solmetex, challenging US 11,589,970 ("Intraoral device with detachable mouth prop"). Grounds visible in the record use Park, Baughan, Johnson, Black (US 8,029,280), and Hirsch (US 2003/0134253) in § 103 combinations; the patent owner's preliminary response argues Petitioner's "bridge structure" and "wave shape" reading is overbroad and that the Park–Baughan–Johnson combination fails to disclose the claimed structure. (Sources: ptacts.uspto.gov exhibit downloads; docketalarm.com IPR2025-01059 exhibit.)
• IPR2025-01059 — Ascentcare Dental Products v. Solmetex, challenging US 11,744,686 ("Intraoral device"); expert declaration of Dr. Brian P. Black, whose US 8,029,280 ("Mr. Thirsty") is the lead reference family. (Source: docketalarm.com IPR2025-01059 exhibit download.)
• IPR2025-01104 — Ascentcare Dental Products v. Solmetex, referenced in a Solmetex exhibit index; the specific challenged patent was not ascertainable from the search results. (Source: ptacts.uspto.gov petition exhibit download.)

I was unable to locate (and therefore do not assert the existence of) an IPR numbered IPR2025-01058, -01060, or any other number directed specifically at the '764. If Ascentcare's campaign maps one-petition-per-family-member (as the '970 and '686 petitions suggest), a petition against the '764 — the "stability bar" member — would plausibly be among the numbers adjacent to 01057/01059, but that is inference, not a confirmed filing, and I did not fabricate a proceeding number.

Strategic summary

Claim status. All 17 claims of US 11,576,764 (independent claims 1 and 16, plus dependents 2–15 and 17) are SUSTAINED and UNTESTED in AIA trial. No claim has been canceled, no FWD exists, and no institution decision has ever been entered. The patent's effective posture is pristine — but unproven.

Estoppel landscape. Because no petitioner has ever been through an IPR on this patent, no § 315(e)(2) estoppel exists against anyone with respect to the '764. Every statutory ground is available: § 102/§ 103 over the same art Ascentcare is already using against the family (Park, Baughan, Johnson, Black/US 8,029,280, Hirsch/US 2003/0134253), plus any art unique to the "stability bar" limitation (claim 1's elongated stability bar lying within the interior space, molded in one piece with the second wall; claim 16's reinforcing-thickness variant). Watch the § 315(b) clock: a defendant served with a complaint asserting the '764 has one year from service to file its own IPR petition.

Pattern signals. The signal here is unmistakable: Solmetex (the Dryshield/Incept family) is being picked apart patent-by-patent by a single, repeat petitioner — Ascentcare Dental Products — using the same expert (Dr. Brian P. Black) and the same Mr. Thirsty/Black prior art across multiple sibling patents. Patent owner Solmetex is defending vigorously, filing detailed preliminary responses attacking the Petitioner's claim constructions (e.g., reading "wave shape" out of the bridge-structure limitation) and raising procedural objections (e.g., translation compliance for the Korean Park reference). Solmetex has also been through inter partes reexamination-era and litigation history on the family, and the Google Patents file shows the family has been in litigation ("Family has litigation" marker). No defensive aggregator (Unified Patents, etc.) appears in the chain — this is a commercial competitor fight.

For a defendant today: the fact that Ascentcare attacked the '970 and '686 siblings but (so far as the record shows) not the '764 is notable — possibly because the '764's stability-bar claims are the hardest to reach with the Black/Park art, or possibly because a petition is already in preparation. Do not assume the '764 is vulnerable just because its siblings are under fire; conversely, do not assume it is strong. The claims are entirely untested, which means a well-researched petition has a real shot — and the Ascentcare papers already teed up the claim-construction battle lines for free.

Recommended next steps

1. If you are a defendant being asserted against the '764 today: There is no FWD to cite because there is no proceeding. Do not represent to a court or opposing counsel that the '764 has been "through IPR" — it has not. Your § 315(b) one-year clock is running from service; if you intend to petition, move quickly and build on the Ascentcare record (Park, Baughan, Johnson, Black, Hirsch combinations) plus any stability-bar-specific art.
2. Monitor the Ascentcare wave: check PTAB E2E (https://ptab.uspto.gov) for IPR2025-01057, IPR2025-01059, and IPR2025-01104 institution decisions — due roughly six months after each filing (mid-to-late 2025 for these). If Ascentcare's constructions prevail on the sibling patents (particularly the "bridge structure"/"wave shape" fight and the "stability bar" fight visible in the '970 record), those rulings will be highly persuasive, though not binding, in any later '764 proceeding.
3. Search again before relying on this memo: the ODP ingest lags live filings. Re-run a PTAB E2E trial-number search for "11,576,764" and watch for an IPR2025-xxxxx petition with that patent number — the gap between the '970/'686 petitions and a possible '764 petition may simply be drafting time.

Confidence note: I confirmed zero ODP-listed proceedings and confirmed IPR activity only against US 11,589,970 and US 11,744,686 (family members). I did not independently confirm the challenged patent in IPR2025-01104, and I found no evidence of any proceeding against US 11,576,764 itself. No proceeding numbers were invented.

Based on the authoritative patent record and legal-event data embedded in the Google Patents text provided, plus limited corroborating web results, here is the reconstructed ownership analysis for US 11576764 B2. Important caveat up front: the correspondent-of-record field is not reproduced in the Google Patents legal-event feed, and my live searches of USPTO Assignment Center / PatentCenter did not return the individual correspondent names before the session limit. I have therefore not fabricated correspondent identities — where they could not be verified, that is flagged explicitly rather than guessed.

Inventors

• Thien Nguyen — Santa Ana, CA (per sibling patent US 9,788,924 B2 cover). Assignor on the original inventor→Incept assignment executed January 2014 (reel 032545/0891). Continued inventing for the DryShield/Solmetex product line into the 2019–2020 era (e.g., Solmetex design filings), i.e., no evidence of early departure from the technology family.
• Tam Thanh Pham — San Francisco, CA (per US 9,788,924 B2 cover). Co-assignor on reel 032545/0891.

Employer at filing: Not independently determinable from the record, but both executed an assignment to Incept, Inc. (not to the named applicant metadata "Solmetex LLC"), which is consistent with their being principals/employees of the Incept startup that developed the DryShield intraoral isolation system. No unusual departure pattern is evident.

Original assignee

The patent text lists "Original Assignee: Solmetex LLC" in the Google metadata and "Current Assignee: Incept Inc / Solmetex LLC." Because this continuation issued 2023-02-14 — after the June 2022 Dryshield→Solmetex assignment (reel 060107/0030) was recorded — the entity named on the issued patent is Solmetex, LLC (Massachusetts).

• Line of business: Solmetex is an operating dental company (Northborough, MA) historically known for amalgam separators / mercury waste and waterline treatment; since 2022 it also owns and sells the DryShield intraoral suction-and-isolation mouthpieces (the product embodying these claims). The Solmetex design-patent family (e.g., USD988505S1 "Mouthpiece," 2023) confirms it commercially sells mouthpieces in this family.
• Product shipping: Yes — DryShield mouthpieces are marketed and sold by Solmetex.
• Current status: Operating (private; subject to lender security interests recorded 2022–2025).

Assignment timeline

The USPTO records as surfaced via the Google Patents legal-event feed show six recorded events. All reel/frame numbers below come from that feed; correspondent names could not be retrieved in this session and are marked unverified.

• 2014-01-06/07 (executed) / recorded 2014-03-27 — Reel 032545/0891

  • Conveyance: Assignment of Assignors' Interest
  • Assignor: Thien Nguyen; Tam Thanh Pham (inventors)
  • Assignee: Incept, Inc.
  • Correspondent: unverified
  • Context: Standard inventor→company assignment on formation of the Incept/DryShield venture.

• 2017-01-27 (effective) / recorded 2017-06-20 — Reel 042916/0954

  • Conveyance: Conversion (entity conversion, not an arm's-length sale)
  • Assignor: Incept Incorporated
  • Assignee: Dryshield, LLC (Fountain Valley, CA)
  • Correspondent: unverified
  • Context: Internal reorganization — Incept Incorporated converted to / was succeeded by Dryshield, LLC; same product, same people.

• 2022-06-03 / recorded 2022-06-03 — Reel 060099/0397

  • Conveyance: Security Interest
  • Assignor: Dryshield, LLC
  • Assignee: Midcap Financial Trust (Maryland)
  • Correspondent: unverified
  • Context: Lender collateral grant (credit facility), not a change of ownership.

• 2022-05-09 (effective) / recorded 2022-06-06 — Reel 060107/0030

  • Conveyance: Assignment of Assignors' Interest
  • Assignor: Dryshield, LLC
  • Assignee: Solmetex, LLC (Massachusetts)
  • Correspondent: unverified
  • Context: Acquisition of the DryShield patent portfolio by operating dental-products company Solmetex (same-day family shows Solmetex taking the whole DryShield patent family, e.g., US 11,589,969, US 11,589,970, US 11,744,686).

• 2022-11-02 / recorded 2022-11-02 — Reel 061637/0932

  • Conveyance: Security Interest
  • Assignor: Dryshield, LLC
  • Assignee: Midcap Financial Trust
  • Correspondent: unverified
  • Context: Supplemental lender collateral grant; dry corporate finance.

• 2025-03-18 / recorded 2025-03-18 — Reel 070544/0954

  • Conveyance: Security Interest
  • Assignors: Dryshield, LLC; Impladent, Ltd.; Solmetex, LLC; Sterisil, Inc.
  • Assignee: Churchill Agency Services LLC, as Administrative Agent (New York)
  • Correspondent: unverified
  • Context: Refinancing — Churchill replaces Midcap as the lenders' administrative/collateral agent across the Solmetex/Dryshield group. Security interest only; Solmetex remains owner of record.

Timeline diagram

timeline
    title Ownership of US 11576764
    2012 : Provisional priority filed
    2013 : Parent application filed
    2014 : Continuation filed
         : Assigned to Incept Inc
    2017 : Converted to Dryshield LLC
    2022 : Acquired by Solmetex LLC
         : Midcap security interest
    2023 : Patent issued
    2025 : Churchill security interest

NPE / troll-pattern signals

1. Shell-entity transfer — Not present. The assignees are (a) the founding operating company (Incept, Inc.), (b) its direct successor by entity conversion (Dryshield, LLC), and (c) an operating dental-products company (Solmetex, LLC) that sells the DryShield mouthpiece line. None is an "IP / Licensing / Holdings" shell; no registered-agent-service addresses appear in the recorded chain.
2. Known asserter in the chain — Not present. Incept, Dryshield, and Solmetex do not appear on the RPX / Unified Patents / Acacia / Marathon / IPNav-type asserter lists. The litigation involving this family is a competitor dispute, not NPE assertion (see below).
3. Repeat correspondent across the chain — Unclear / unverified. I could not retrieve correspondent names from USPTO Assignment Center in this session, so no recurrence finding can be made. (This is a data gap, not an exculpatory finding.)
4. Cascading transfers — Not present. Events are spaced 2014 → 2017 → 2022 → 2025: an entity conversion, one genuine acquisition, and two lender security grants. No chained-LLC conveyor belt within 24 months.
5. Pre-litigation transfer — Not present (on available evidence). The Dryshield→Solmetex transfer (reel 060107/0030, June 2022) moved the patent to the operating company that sells the product, which is the opposite of an NPE-enabling arrangement. The family does carry a litigation flag (Darts-ip family 50881306), and Ascentcare Dental Products — a dental-accessories competitor — has challenged Solmetex's patent in IPR2025-01104, consistent with operating-company enforcement rather than a standing-arranged NPE suit.
6. Bankruptcy fire-sale — Not present. No insolvency proceeding appears in the chain; the 2022 transfer was a commercial acquisition and the 2022/2025 recordings are ordinary lender security interests.
7. Privateering — Not present. Solmetex sells the DryShield product itself; there is no evidence it transferred the patent to a proxy to sue competitors on its behalf. If anything, the Ascentcare IPR shows Solmetex defending/asserting in its own name.
8. Defensive aggregator (anti-NPE) — Not present. The chain terminates at Solmetex, an operating company, not RPX / AST / Unified / LOT / OIN.

Verdict

Operating-company assertion

The recorded chain (reels 032545/0891 → 042916/0954 → 060107/0030) runs inventor → Incept, Inc. → Dryshield, LLC → Solmetex, LLC, with the only other recordings being lender security interests to Midcap Financial Trust (060099/0397, 061637/0932) and Churchill Agency Services (070544/0954). Solmetex is an operating dental company that markets the DryShield mouthpieces embodying these claims (confirmed by its Solmetex mouthpiece design-patent family), and the litigation signal on the family (including Ascentcare's IPR2025-01104 against Solmetex) is competitor-versus-operating-company activity, not NPE assertion. No shell transfers, known asserter, cascading LLC chain, or bankruptcy fire-sale appears anywhere in the record.

Verification: Correspondent-level detail and the official images of each conveyance should be confirmed at the USPTO Assignment Center — https://assignmentcenter.uspto.gov/ — by searching patent number 11,576,764 (reels 032545/0891, 042916/0954, 060099/0397, 060107/0030, 061637/0932, 070544/0954). Reel/frame numbers and dates above are taken from the Google Patents legal-event record for the patent as provided; I could not independently re-pull the USPTO correspondent fields in this session.

I'll research the prior art citations for US Patent 11,576,764. Let me run targeted searches.

The Justia page confirms the citation list. Let me verify bibliographic details for the most significant references cited against this patent.

Excellent — I've confirmed key details on Black (US 8,029,280) including the examiner's mapping of its transverse walls as a "wave-shaped bridge structure," plus Black's longitudinal stiffeners 447/545 (directly relevant to the stability bar claim). Let me verify a few more key cited references.

Prior Art Analysis — U.S. Patent No. 11,576,764 ("Intraoral Device with Stability Bar")

Scope and methodology

I treated the Google Patents "Citations (94)" / "Patent Citations (137)" listings reproduced in the authoritative patent text as the complete universe of cited references, and verified the most important ones against live records (Justia, patentimages, PTAB IPR2025-01057/01059/01020 exhibit downloads, Google Patents). Because the '764 claims trace to provisional application 61/734,939 (Dec. 7, 2012), filed before the AIA's March 16, 2013 transition, pre-AIA §§ 102/103 govern. Under pre-AIA § 102(b), a reference is a statutory bar if patented or published before December 7, 2011; references from a US application filed by another before Dec. 7, 2012 but published later are § 102(e) art.

Claims at issue. Independent claims 1 and 16 (dental mouthpiece with: main body pocket having a first end wider than a rectangular second-end portion; a first wall; a spaced second wall carrying (i) an elongated stability bar inside the interior space extending into the rectangular portion, molded one-piece with the second wall, and (ii) an integral wave-shaped bridge structure of crests/troughs that spans toward but is not attached to the first wall; a connector wall; and a cheek retractor at the second end). Dependents 2–15 (claim 1) and 17 (claim 16) add cheek-retractor geometry/resilience, spaced contact points, a suction connector, one-piece injection molding, silicone material, differing wall thicknesses, and a detachable mouth prop with bite block/strap/plug/notch features.

A strict § 102 anticipation requires every claim element in a single reference. Candidly: no cited reference cleanly discloses the full combination of an interior, longitudinally-extending stability bar molded with one wall plus a wave bridge unattached to the opposite wall plus a connector-walled enclosed pocket — which is why the claims ultimately issued. But several references come close enough that anticipation is a genuine construction-driven question for specific claims, and the same references are powerful § 103 primaries. Below, each reference is assessed for what it discloses and which claims it could potentially anticipate.

TIER 1 — References with genuine single-reference anticipation potential for the independent claims

1. Hirsch / Innerlite "Isolite" family — closest single-reference corpus

Brief description. The Isolite device is a one-piece, flexible, injection-molded body of a single homogeneous material forming upper and lower front/rear flap pairs whose edges seal against the palate and mouth floor to create evacuation channels; evacuation holes perforate the flaps; a connection section exits the mouth to a vacuum source; and a bite block with integral tongue/cheek retractor holds the mouth open. The family's own prosecution record (mirrored in the Ascentcare IPRs on the sibling patents) shows the examiner repeatedly mapped Hirsch's structure onto the claimed mouthpiece: a pocket-type body with anterior and posterior walls, a connecting side wall/edge, perforations, a suction connector, a cheek retractor of resilient material, a mouth prop with bite block and strap — and a wave-shaped "bridge structure 24" with crests/troughs formed on one wall interior.

§ 102 assessment. Hirsch is § 102(b) statutory-bar art (published/patented long before Dec. 7, 2011). As the primary reference in the family's prosecution, it is the strongest anticipation candidate for the structural skeleton of claims 1 and 16: the two spaced walls, the connecting wall, the wider-at-one-end/narrower-at-the-other body geometry, the cheek retractor at the second end (claims 1/16 element sets), and dependent claims 2–4 (cheek-retractor pressure surface, rectangular portion narrower than the retractor), 6 (suction connector to vacuum), 7 (one-piece injection molding), 8 (flexible translucent autoclavable silicone-type material), and 10–15 (detachable mouth prop with bite block, strap, plug/slot, flush notch — the examiner in the sibling "mouth prop" case found Hirsch's mouth prop 26 / bite block 94 / strap 100 / plug structure there). Genuine anticipation gaps for claims 1/16: Hirsch's Isolite structure is flap/channel-based (walls sealing against oral tissue) rather than a self-enclosed pocket, and Hirsch does not clearly disclose (i) a stability bar lying in the interior space extending into a rectangular portion, molded one-piece with a wall, or (ii) a bridge structure that is integral with one wall and not attached to the other — Hirsch's bridge 24 is characterized (per the applicant's own distinction in the family) as a separate dispersion piece. These are the elements that would defeat pure § 102 anticipation and push reliance to § 103.

2. Black — US 8,029,280 B2 / US 2009/0274991 A1 ("Mr. Thirsty")

Brief description. An intra-oral isolation device: a tongue-shield aspirator (40/140/340/440/540) with a first/posterior layer (348a) and a second/anterior layer (348b) spaced apart by a plurality of transverse walls (348c) defining an axial passageway and angled upper/lower channels; a hollow neck; a bite member with an oblique conduit; a bite grip (upper/lower members for the teeth); and an evacuation tube connecting directly to an HVE valve. The aspirator is unitary, flexible, position-memory material and is placed by bending the distal segment around the posterior molars — the same posterior-wrap function as the '764 stability bar. Crucially, Black discloses longitudinal stiffeners (447 on the anterior layer; optional posterior longitudinal stiffener 545) "to prevent kinking when the tongue shield aspirator is flexed and/or bent for placement" — the closest prior-art analogue to the claimed stability bar.

§ 102 assessment. § 102(b) art (issued/published before Dec. 7, 2011). Black is the reference the USPTO actually used against the sibling "bridge" claims: Dr. Black's own IPR declaration confirms the Examiner found that Black's transverse walls 348c are "a bridge structure protruding from an interior surface of the posterior wall… comprising a plurality of spaced contact points that keep the anterior wall separated from the posterior wall during suction," with "crests" and "troughs between bridges/transverse walls 48c allow[ing] for communication with the suction source" — i.e., the examiner equated Black's walls with the claimed wave-shaped bridge structure (claim 1/16 bridge element; dependent claim 5's "spaced contact points"). Black's longitudinal stiffener 447/545 is the natural reading for the elongated stability bar element. Anticipation gaps: (i) Dr. Black himself states "my patent opted for open sides" — the spaced layers lack a lateral connector wall running between the walls as claim 1 requires; (ii) the stiffeners appear on the exterior of the layers ("on the back… side of the posterior layer"), not "lying within the interior space between an interior surface of the first wall and an interior surface of the second wall"; (iii) the bridge walls 348c appear to span and connect the two layers, arguably "attached" to both, conflicting with the "not attached to the first wall" limitation added (per Black's declaration) specifically to distinguish his device. If a court reads those limitations broadly (e.g., stiffener 447 as inside the passageway; a connector formed by the transverse-wall edges), Black potentially anticipates claims 1 and 16; otherwise it is the strongest § 103 secondary reference for the stability-bar limitation. Black also supports dependent claims 2–4, 6–8 (cheek retractor of position-memory material, bite member, HVE hookup, unitary flexible construction).

3. Costello — US 6,213,772 B1 / WO 00/61031 A1

Brief description. A U-shaped, essentially hollow retraction member having an inner wall and an outer wall with an internal divider defining upper and lower evacuation chambers, each with suction-inlet ports/apertures through the inner wall and suction-outlet members attachable to high- and low-volume suction. A cheek-retraction arm (52) and tongue-retraction arm (50) are joined by a U-shaped hinge (54) with position memory; the device is compressed, inserted around the rearmost tooth/posterior alveolar ridge, and released so the arms actively retract cheek and tongue, with only the suction outlet protruding from the mouth.

§ 102 assessment. § 102(b) art. Costello discloses a hollow, walled evacuation body with apertures and a cheek retractor (claims 1/16 wall/pocket/cheek-retractor elements in broad form; dependent claims 2–4's retraction geometry; claim 6's suction connector concept), but the structure is a U-shaped inner/outer-wall chamber — not an anterior/posterior walled pocket with a connector wall — and it lacks any stability bar or internal wave bridge. Anticipation of claims 1/16: unlikely; Costello functions best as a § 103 co-reference supplying the motivation (wall-collapse-resistant perforated evacuation body with active cheek retraction) for combining Hirsch's and Black's structures.

TIER 2 — References that disclose substantial sub-combinations (more useful under § 103; anticipation only of narrow dependent claims)

TIER 3 — Background saliva-ejector / mouth-prop art (analogous field; generally too remote to anticipate the claimed pocket-plus-bar-plus-bridge structure)

These older references are cited for the long-recognized state of the art (saliva ejection, mouth propping, tissue retraction) and are unlikely § 102 anticipations of any claim, because none discloses the '764's two-walled pocket with integral stability bar and unattached wave bridge; they matter mainly as § 103 background showing the combined functions were old:

• US 50,461 A (Dibble, 1865) — early dental apparatus.
• US 1,471,207 A (Riddle, 1923) and US 1,731,322 A (Riddle, 1929) — sanitary individual saliva ejectors.
• US 2,937,445 A / US 3,090,122 A (Erickson, 1960/1963) and US 3,924,333 A (Erickson, 1975), US 4,192,071 A (Erickson, 1980) — dental appliances with fluid collection/drainage, cheek retraction, bite support.
• US 3,453,735 A (Burt, 1969) — dental aspirator.
• US 3,516,160 A (Leffler, 1970) — dental aspirating cuspidor.
• US 3,758,950 A (Krouzian, 1973) — dental ejector equipment.
• US 3,768,477 A (Anders, 1973) — tongue-depressing aspirating tip.
• US 3,802,081 A (Rogers, 1974) — tongue controller saliva ejector.
• US 3,857,181 A (Rappaport, 1974) — dental shield.
• US 3,877,691 A (Foster, 1975) — venting shield (anesthesia context).
• US 4,017,975 A (Johnson, 1977) — saliva ejector and chin holder.
• US 4,024,642 A (Zorovich/Johnson & Johnson, 1977) — dental appliance.
• US 4,083,115 A (McKelvey, 1978) — dental saliva ejector.
• US 4,511,329 A (Diamond, 1985) — moisture-controlling lingual dental mirror.
• US 4,718,662 A (North, 1988) — tongue positioning/exercising device.
• US 4,802,851 A (Rhoades, 1989) — dental appliance.
• US 4,975,057 A (Dyfvermark, 1990) — dental appliance.
• US 5,009,595 A (Osborn, 1991) — dental mouth prop.
• US 5,078,602 A (Honoshofsky, 1992) — saliva ejector/cleaning method.
• US 5,720,275 A (Patil, 1998) — tracheal guide (remote field).
• US 5,730,599 A (Pak, 1998) — protective dental shield.
• US 5,762,496 A (Albertsson, 1998) — disposable dental saliva ejector.
• US 5,890,899 (see Tier 2), US 6,022,214 (see Tier 1), US 6,241,521 / 6,261,591 (see Tier 2).

TIER 4 — Design patents and non-analogous art (no § 102 anticipation as a matter of law / fact)

• Design patents: USD267586 (Hatlen, 1983, mouth prop), USD364456 (Solnit, 1995, aspirator tip), USD495799 / USD497426 / USD615203 (Innerlite/Isolite designs), USD663831 (Safe-Vac dental suction tool, 2012), USD666726 (Surgovations bite block, 2012), USD735858 (Innerlite, 2015), USD737964 (Ultradent cheek retractor, 2015), USD782047 / USD782048 / USD787069 / USD787070 (Ascentcare Dental Labs, 2017), USD868958 (Reyes, 2019). Design patents claim only ornamental appearance and cannot anticipate utility claims under § 102 (they lack the functional structural disclosure required), though they corroborate the crowded design field.
• Non-analogous / irrelevant to anticipation: US 2,019,612 A (Langhans, 1935 — X-ray tube support structure); US 6,672,305 B2 (2004 — shallow-throat orotracheal intubation guide); US 5,720,275 (tracheal guide, above); US 2006/0063126 A1 (Aloise — medical needle manufacturing); KR100654392 B1 (oral illuminator); CN102247140 A (multifunctional ECG examining table); US 2012/0015317 A1 (fume/smoke evacuation); US 2013/0252193 A1 (tooth positioner/vibrator); FR2992161 A1 (Braud, intra-oral protection, 2013). These were cited on the face of the patent (often by the examiner as "of interest") but are outside the field of intraoral dental suction mouthpieces and provide no § 102 anticipation of any claim.

TIER 5 — Cited references that are NOT prior art (same family / same inventive entity / post-priority)

These appear in the citation list but cannot support a § 102 rejection because they are the applicant's own family (35 U.S.C. § 103(c)/pre-AIA common-ownership and same-inventive-entity rules) or post-date the effective filing date:

• US 2014/0162209 A1 (Incept, "Intraoral dental suction and isolation system," publ. 2014-06-12) and US 8,911,232 B2 (parent, issued 2014-12-16) — direct parent/continuation of the '764; same inventors.
• US 2014/0212837 A1 / -0212838 A1 / -0212839 A1 / -0212840 A1 / -0212841 A1 (Incept, 2014-07-31 publications of the five sibling applications, including the '764's own pre-grant publication) and the resulting US 9,788,924 B2 / 11,589,969 B2 / 11,589,970 B2 / 11,744,686 B2 / 12,011,329 B2 — siblings from the same Dec. 7, 2012 priority application, same inventors.
• Family foreign filings (CA2851861, WO2015/088577, EP2903557, CN105578986, EP3184076) — same-family publications.
• Later-filed third-party applications that post-date Dec. 7, 2012 (e.g., Reyes US 2017/0156831–33, filed Dec. 7, 2015; Innerlite US 9,358,086/9,084,656/2015/0335409 filed 2014–2015; Ascentcare US 9,968,341 filed 2015; US 2015/030...) — not § 102 prior art against claims entitled to the 2012 priority date under pre-AIA law.

Bottom line: most relevant prior art and anticipation exposure

1. Strongest single-reference anticipation candidates for claims 1/16: Black (US 8,029,280) — whose transverse walls the examiner already equated to the claimed wave bridge and whose longitudinal stiffeners 447/545 are the closest stability-bar analogue — and Hirsch/Innerlite (US 2003/0134253 and its issued family), which supplies the entire pocket/wall/connector/cheek-retractor/suction skeleton. For each, anticipation of the independent claims turns on two construction battles: whether a "connector wall" is present (Black's open sides vs. Hirsch's tissue-sealed flaps), and whether any disclosed stiffener/bridge sits "within the interior space," is "molded in one piece" with the second wall, and is "not attached to the first wall." Those are genuinely disputable; a patent owner would argue neither reference anticipates, which is consistent with the claims issuing.
2. Most likely to anticipate narrow dependent claims: Hirsch for claims 2–4, 6–8, 10–15 (mouth prop/bite block/strap geometry — already found in Hirsch by the family examiner); Black for claims 2–5, 6–8 (bridge crests as spaced contact points); Costello, Hickham, Schubert, Barstow, Garrison, Centrix, Ultradent, Kanas, Suzman, and Ames for individual functional limitations (cheek retraction, suction connector, bite block/mouth prop) as mapped above.
3. Every Tier 1–2 reference is § 102(b) or § 102(e) prior art (all published/patented or filed before the Dec. 7, 2012 priority date), so no § 102(b) on-sale/publication-bar timing issue protects the '764 from this core set.

Confidence note: Hirsch's and Black's element-level disclosures are verified through the family's prosecution record and the Ascentcare IPR exhibits (including Dr. Black's own declaration quoting the Examiner's bridge-structure mapping); Costello, Hickham, and Schubert were verified against the primary patent documents. Where I characterize a limitation as "genuinely disputable" for anticipation, that reflects the strict single-reference § 102 standard applied to structural details (stability-bar location, connector-wall presence, bridge attachment) that I could not fully resolve from the retrieved figures alone.

Obviousness Analysis — U.S. Patent No. 11,576,764 ("Intraoral Device with Stability Bar")

Scope, sources, and confidence caveats

This analysis uses the prior-art record assembled on the Google Patents page for US 11,576,764 B2 (the "Citations," "Patent Citations," and "Non-Patent Citations" listings) as the primary reference universe, as instructed. I have supplemented that list with (a) the specification and claims of the '764 patent itself, and (b) publicly retrieved USPTO/PTAB documents that corroborate how several of these references have already been applied to the sibling patents in the same family (U.S. 11,589,969, 11,589,970, 11,744,686, 11,826,217, 12,011,329) during prosecution and in IPR2025-01020/01057/01059/01065 and a petition on 12,011,329 (Ascentcare Dental Products, Inc. v. Solmetex, LLC, related to Solmetex v. Ascentcare, No. 1:24-cv-00954, W.D. Mich.).

Three honesty flags before the substance:

1. No IPR directed specifically to the '764 patent was identified. The retrieved IPR petitions name the sibling patents, not 11,576,764. My obviousness analysis is therefore a standalone § 103 assessment built from the cited record, not a description of a pending ground.
2. Reference-element details are only as reliable as the record retrieved. I verified significant structure of the Hirsch/Innerlite family, the Black references, and Costello from patents/Office Actions retrieved via search. Where a structural conclusion is inferred rather than verified (notably the "stability bar" analogues), I say so expressly.
3. Prosecution history of the family is highly probative. The USPTO record shows examiners repeatedly mapped the claimed mouthpiece structure onto Hirsch (US 2003/0134253 A1) — including a wave-shaped "bridge structure 24," perforations, a pocket body, a cheek retractor, and a mouth prop — and combined Hirsch with Sclafani (US 5,890,899) and others under § 103. Those examiner positions are powerful evidence that the cited art, read as a POSITA would read it, covers most of the '764 claim elements.

I. Legal framework

Obviousness under 35 U.S.C. § 103 is governed by Graham v. John Deere Co., 383 U.S. 1 (1966): (1) scope and content of the prior art; (2) differences between the prior art and the claims; (3) level of ordinary skill; and (4) objective indicia of non-obviousness. Under KSR Int'l Co. v. Teleflex Inc., 550 U.S. 398 (2007), a flexible "motivation to combine" inquiry applies: a combination of known elements is obvious when a POSITA would have had reason to combine them with a reasonable expectation of success, driven by design need, market pressure, "obvious to try," or the predictable substitution/improvement of known components. A patent composed entirely of prior-art elements, each performing its known function and yielding a predictable result, is ordinarily obvious.

II. The claimed invention and the differences from the prior art

Independent claim 1 requires, in substance:

1. a main body portion with a first end wider than a rectangular portion at a second end, the body forming a pocket enclosing an interior space;
2. a first wall defined by an exterior edge, extending end-to-end, wider at the first end;
3. a second wall spaced from the first wall, with a corresponding exterior-edge shape, wider at the first end, itself carrying:
   • an elongated stability bar inside the interior space between the two walls' interior surfaces, extending along the longitudinal axis into the rectangular portion, molded in one piece with the second wall; and
   • a bridge structure comprising protrusions integral with the second wall's interior surface, substantially spanning the wall-to-wall distance, not attached to the first wall, arranged in a wave shape with crests and troughs;
4. a connector wall joining the two walls; and
5. a cheek retractor at the second end.

Independent claim 16 is substantively the same, with the stability bar characterized as "reinforcing a thickness of material along the longitudinal axis"; claim 17 adds that the bar extends through the narrower portion toward the cheek retractor.

Properly framed, the inventive residue of the independent claims over the closest art is confined to three structural details: (i) the wave-shaped internal bridge that contacts but is not bonded to the opposite wall, (ii) the longitudinal stability bar inside the pocket extending into the neck/rectangular portion, and (iii) the specific tapered-to-rectangular footprint of a two-walled pocket terminating in a cheek retractor. Each of these is, in the record, either already present in the cited art or an obvious mechanical expedient.

III. Person of ordinary skill in the art (POSITA)

A POSITA would be a person with (a) a B.S. or equivalent in mechanical or biomedical engineering, industrial design, or a related discipline; (b) two to four years of experience designing intraoral/dental suction, isolation, or bite-block devices; (c) working familiarity with dental anatomy (posterior arch, cheek/lingual tissues, HVE connections); and (d) practical knowledge of injection molding of flexible, autoclavable elastomers (silicone, TPE). Such a person would routinely consult dental-evacuator patents and catalogs and would understand the functional requirements of hands-free isolation: retraction, fluid/debris capture, anti-collapse under high vacuum, patient comfort, and one-piece manufacturability.

IV. The closest prior art (from the '764 record)

1. The Hirsch / Innerlite "Isolite" family — the closest single reference

U.S. 2003/0134253 A1 and its utility family (US 6,338,627; 6,575,746; 6,908,308; 6,974,321; 7,297,990; 7,748,981; 8,057,227/8,057,228; 8,075,310; 8,297,973) disclose one-piece, flexible, injection-molded intraoral devices of a single homogeneous material with upper/lower evacuation channels, evacuation holes, a cheek-retraction function, and a connection section to a vacuum source.

Critically, the USPTO has already taken the position, in Office Actions on the sibling applications (retrieved from PTACTS), that Hirsch 2003/0134253 discloses: a dental mouthpiece (50) configured as a pocket with an anterior wall (convex face), a posterior wall (concave face), and a side wall (edge 22/56) connecting them; perforations (60, 68); a suction connector (74/84/86); a cheek retractor (52) formed of the same resilient material; a mouth prop (26) with bite block (94) and strap (100); and a "bridge structure 24 having a wave shape." The applicant's responses did not dispute the existence of Hirsch's wave-shaped structure 24; they disputed integration (Hirsch's dispersion piece 24 is slidably received by the retractor rather than unitary with the suction connector) and disputed that Hirsch shows certain connector/strap geometry.

Hirsch 2003/0134253 therefore supplies, by the examiner's own prior analysis, nearly the entire pocket-body skeleton of claim 1: two spaced walls, a connecting side wall, perforations, a cheek retractor, a suction connector, and a wave-shaped internal bridge. The chief gaps the examiner's mapping did not fill are the stability bar and the contact-not-attached characterization of the bridge — both addressed below.

2. Black — US 2009/0274991 A1 / US 8,029,280 B2 ("Edge Medical Technologies")

Black discloses an intra-oral device with a tongue-shield aspirator having tongue-retractor and cheek-retractor portions, a bite member with conduits, and an evacuation tube connectable to an HVE valve. The device is unitary and flexible, made of position-memory material, and is positioned by bending around the posterior mouth — the same "wrap the distal segment around the last molar" function the '764 stability bar serves. Black's bite grip includes a vertical spine (28) joining upper and lower members — i.e., a longitudinal reinforcing spine in a flexible intraoral part. Black also discloses the lateral orifice (12) and anterior opening (18a/19) by which the evacuation tube is received (the examiner in the family treated orifice 12 as the claimed "strap" analogue).

Black is the natural secondary reference for (a) a longitudinal spine/bar used to reinforce a flexible intraoral suction device and (b) the general design of flexible, position-memory mouthpieces that wrap posteriorly — precisely the design problem the '764 stability bar addresses.

3. Costello — WO 00/61031 / US 6,213,772 ("Oral isolation device with evacuation chambers")

Costello discloses an oral isolation device with upper and lower evacuation chambers having suction-inlet apertures for evacuating saliva, aerosol, and debris, and arms that exert opposing pressure against the cheek and tongue for active retraction — solving the very "cheek retraction + full-arch evacuation" problem. Costello's chambers are bounded by walls and must resist collapse while under suction, and its device is designed to conform to the patient's mouth rather than forcing the mouth to conform. Costello supplies the perforated two-wall pocket concept and the reason one would add internal spacing structure.

4. Hickham — US 5,037,298 ("Apparatus and improved process for removing saliva while retracting cheeks and lips")

Early but on-point teaching that saliva removal and cheek/lip retraction belong in one hands-free device — the foundational functional combination.

5. Sclafani / Intellitech — US 5,890,899 ("Dental isolator")

Already used by the examiner in combination with Hirsch (in the family) — e.g., to supply features missing from Hirsch. It is a dental isolator useful as a filler reference.

6. Other record references

Isolite design patents (USD 495,799; USD 497,426; USD 615,203), Barstow (US 6,261,591, dental prop/throat dam/retractor), Garrison (US 6,241,521), Ultradent bite blocks (US 6,655,960; 6,659,227), Kanas (US 2008/0166684), Suzman (US 2008/0318183), Ames (US 2013/0095450), Centrix (US 8,535,056), Innerlite's later US 9,358,086/9,084,656/2015/0335409, and the DryShield 2020 publications (US 2020/0352680) round out a crowded field in which flexible, autoclavable, one-piece suction/isolation mouthpieces with cheek retractors, perforated bodies, bite blocks, and HVE connectors were all well known before the 2012 priority date.

V. Proposed § 103 combinations and element mappings

Combination A (strongest): Hirsch 2003/0134253 in view of Black 8,029,280 (optionally + Costello 6,213,772)

Primary reference — Hirsch. As mapped by the examiner in the family's prosecution, Hirsch supplies: the pocket main body with first and second walls and a connecting side wall (elements [1]–[4] of claim 1 except the stability bar), the perforated walls, the suction connector, the cheek retractor at the second end (cheek retractor 52 / tongue-and-cheek retractor 22), and a wave-shaped bridge structure (24) with crests/troughs formed on one wall interior (element [3b]). The tapered/rectangular footprint — a body that is wider at the posterior/operative end and narrows to a neck-like rectangular portion where it meets the cheek-retractor region — is inherent in Hirsch's mouthpiece shape (narrowing toward the corner-of-mouth exit region), which a POSITA viewing Hirsch's figures would immediately recognize as the standard geometry needed for the device to exit the commissure.

Secondary reference — Black, for the stability bar (element [3a]). Black's bite grip uses a vertical spine (28) — a one-piece, molded longitudinal reinforcement in a flexible intraoral member — and Black's whole device is designed to be bent to the posterior intraoral shape, held by "position-memory." A POSITA needing to keep Hirsch's flexible neck region from collapsing or kinking while the mouthpiece wraps around the last mandibular molar would look to Black's spine and provide an elongated bar molded integrally with the wall, lying in the interior space along the longitudinal axis into the rectangular portion. This is a textbook case of taking a known reinforcing structure (a longitudinal rib/spine in a flexible molded part) and placing it where the known need exists (the flexible neck of a suction pocket).

Optional third reference — Costello, for the motivation. Costello independently teaches the problem Hirsch/Black do not emphasize: a perforated multi-wall evacuation body whose walls must not collapse under suction, with active cheek retraction. Costello gives the POSITA the explicit reason to ensure wall spacing is maintained (continuous evacuation while the cheek is retracted), reinforcing the motivation to add both the bridge and the bar.

Why a POSITA would combine. (i) Same field, same problem: all three are intraoral dental suction/isolation devices for hands-free operation. (ii) Complementary gaps: Hirsch lacks an anti-collapse stiffener in the neck; Black supplies a spine; Costello supplies the collapse-prevention rationale. (iii) Predictable result: adding a molded longitudinal bar to a flexible silicone wall and letting a wave-shaped bridge contact (without bonding to) the opposite wall yields exactly the predictable mechanical result — the pocket stays open under HVE vacuum, the neck holds its posterior-wrap shape, and the part still flexes for insertion. (iv) KSR "obvious to try": with a finite set of known solutions to wall collapse (ribs, standoffs, thicker walls, bridge spacers), selecting a longitudinal bar + wavy standoffs is the sort of routine design optimization KSR treats as obvious.

Combination B: Black 8,029,280 as primary, modified with Hirsch's wave-bridge and pocket geometry

Black already gives the cheek retractor, tongue shield, bite member, flexible position-memory body, and HVE hookup. A POSITA would (i) convert Black's open shield into a closed perforated pocket by following Hirsch's two-wall, side-wall, perforated body (an obvious reshaping to capture fluid on both buccal and lingual sides — the exact improvement Costello credits as desirable), and (ii) add Hirsch's wave-shaped internal bridge to keep the new pocket's walls apart under suction. The stability bar is already present in substance via Black's spine concept, repositioned into the pocket interior along the longitudinal axis — an obvious relocation. This combination reads on every element of claims 1 and 16.

Combination C: Costello 6,213,772 with Hirsch/Innerlite and Black

Costello's perforated evacuation chambers and active cheek/tongue retraction arms map to the two-wall perforated pocket and cheek retractor. Hirsch supplies the unitary molded construction, the wave-shaped internal bridge, and the tapered/rectangular body shape; Black supplies the longitudinal spine. Combining Costello's full-arch evacuation body with the known unitary Isolite-style construction is the kind of "improvement of a known device by substituting known components yielding predictable results" KSR identifies as obvious.

Combination D: Hickham 5,037,298 or Barstow 6,261,591 as functional starting points

These are weaker as primaries but confirm the long-recognized design need (hands-free saliva removal with simultaneous cheek/lip retraction) and would be cited to defeat arguments that the combination of functions was itself non-obvious.

VI. The three "inventive-looking" details are each obvious in this record

1. Wave-shaped bridge, integral with one wall, not attached to the other. Wave/corrugated spacers and standoffs that maintain a gap between opposed walls of a flexible suction or fluid channel while leaving open flow paths between "crests" were conventional in flexible medical suction devices long before 2012. Hirsch's own wave-shaped structure 24 (as characterized by the examiner) supplies the shape; the choice to mold the spacer integrally with one wall is the standard way to form such a feature in an injection-molded silicone part, and the choice to leave the crests in contact but unbonded to the opposite wall is an obvious design selection to preserve flex and simplify tooling (no second bond line, no pinch point). No unexpected result is shown from contact-without-attachment.

2. Longitudinal stability bar molded with the second wall. A thickened rib/bar running along the long axis of a flexible molded part, to stiffen a narrow neck and control where it bends, is elementary mechanical design. Black's spine (28) and analogous reinforcing ribs in flexible bite blocks and evacuators in the record (Ultradent 6,655,960/6,659,227; Centrix 8,535,056) show the concept was well developed. Locating it inside the pocket between the walls is dictated by the geometry (the neck region is a hollow pocket; the only place for an internal stiffener that does not obstruct the exterior is inside the pocket), and molding it "in one piece" is the default for the claimed silicone injection-molded construction.

3. Tapered-to-rectangular footprint. This is simply the shape a mouthpiece must take to lie along the posterior arch and exit the corner of the mouth — visible in the Isolite/Hirsch and Black designs. A "wider operative end, narrow exit neck" geometry is a functional shape dictated by anatomy, not an inventive departure.

VII. Dependent claims

Claims 2–15 and 17 add features that are individually routine and, in most cases, expressly present in the cited art:

• Claims 2–4 (cheek retractor geometry, rectangular portion narrower than the retractor, bar reinforcing resilience): inherent in Hirsch (retractor 52 of resilient material at the narrow end) and Black; the bar's resilience function is the predictable purpose of any stiffener.
• Claim 5 (bridge protrusions = spaced contact points): the functional definition of wave crests contacting the opposite wall.
• Claim 6 (suction connector to vacuum source): Hirsch (74/84/86), Black (evacuation tube to HVE), Costello.
• Claims 7–8 (one-piece injection molding; flexible translucent autoclavable silicone): Hirsch/Innerlite disclose one-piece injection molding of flexible elastomer; autoclavable/translucent silicone was standard (the parent '232 patent and DryShield literature confirm the material was known in the field).
• Claim 9 (different wall thicknesses): routine design choice.
• Claims 10–15 (detachable mouth prop with bite block + strap, plug-and-slot, flush-fit notch): the examiner already found these in Hirsch 2003/0134253 (mouth prop 26, bite block 94, strap 100, plug 88/90, flush external surfaces) during prosecution of the sibling "mouth prop" patent; Black's bite member/bite grip and lateral orifice were also mapped onto these features by the examiner.
• Claims 16–17: same as claim 1 with the bar's stiffening function made express — fully addressed by Combinations A–C.

VIII. Anticipated counterarguments and their weaknesses

Patent owner would likely argue: (1) no reference discloses a bridge not attached to the opposite wall; (2) Hirsch's "bridge 24" is a removable dispersion piece, not an integral wall protrusion; (3) no reference discloses the stability bar in the pocket interior; and (4) objective indicia — commercial success of DryShield/Isolite products, long-felt need for hands-free isolation, and industry copying — weigh against obviousness. Each has limited force on this record:

• The examiner's own Hirsch mapping (family prosecution) shows that the wave-shaped bridge and pocket structure were found in Hirsch; the applicant's distinctions in the sibling cases turned on connector integration and strap geometry, not on the bridge or bar — and those distinctions were claim-specific, not structural discoveries.
• The "contact but not attached" limitation is a design choice with no demonstrated unexpected result; KSR forecloses giving patentable weight to an obvious alternative (contacting spacer vs. bonded spacer) with the same function.
• The stability bar is a straightforward rib; in the absence of evidence of a surprising functional effect (e.g., a showing that the bar produces a new mode of posterior wrap not achievable by prior devices), it is an obvious expedient.
• Objective indicia, if proved, must be tied to the claimed features rather than to the overall product; the crowded prior-art field and the existence of simultaneous near-identical sibling filings undercut any suggestion of a long-felt, unsolved need for the specific structure. Note also that the family's validity is already contested in W.D. Mich. and in the sibling IPRs, and the IPR petitions rely on the same class of art (Hirsch, Black, Costello-type devices) — though, again, no IPR directed at the '764 patent itself was identified in the retrieved documents, so this analysis stands on the cited art alone.

IX. Conclusion

On the record cited in the '764 patent, the strongest § 103 ground is Hirsch (US 2003/0134253 A1) as primary, in view of Black (US 8,029,280 B2 / US 2009/0274991 A1), optionally further in view of Costello (US 6,213,772 B1). Hirsch supplies the two-walled perforated pocket, connecting side wall, wave-shaped internal bridge, cheek retractor, and suction connector — a mapping the USPTO itself adopted for the family. Black supplies the longitudinal reinforcing-spine concept and the flexible position-memory, posterior-wrap design context for the claimed stability bar. Costello supplies the articulated rationale (wall-collapse prevention in a full-arch perforated evacuation body with active cheek retraction) that makes the combination coherent rather than hindsight-driven. Under Graham and KSR, a POSITA would have had ample reason to combine these known elements with a reasonable expectation of success, and the residual claim details — contact-not-bonded bridge crests, an internal longitudinal bar, and a tapered-to-rectangular footprint — are obvious design choices. Independent claims 1 and 16, and their dependents, would likely be held obvious under 35 U.S.C. § 103 on this record, subject to any contrary objective-indicia evidence of non-obviousness specific to the claimed features.

Confidence note: this conclusion rests on examiner mappings and reference structures that I verified through retrieved USPTO/PTAB documents and patent text; where a specific figure element could not be independently verified (particularly Black's spine 28 as a direct analogue of the claimed "stability bar," and the precise geometry of Hirsch's wave-shaped bridge 24), the analysis relies on the examiner's characterization in the family's file history, which is probative but should be confirmed against the primary references before use in an adversarial proceeding.