US 11219582

I'll search for authoritative information on US 11219582, including any 2026 CAFC docket activity.

Let me search specifically for any 2026 Federal Circuit docket activity involving this patent.

US Patent 11,219,582 — Analyst Summary

Important scope note on the search: I ran targeted searches for the specific number 11219582 and for CAO Group's 2026 appellate activity. I found no 2026 Court of Appeals for the Federal Circuit docket naming US 11,219,582. The 2026 Federal Circuit / Supreme Court items that surface for "CAO" relate to a different party and different patents — CAO Lighting, Inc. v. Wolfspeed, Inc., No. 25-1068 (cert. denied May 18, 2026), concerning U.S. Patents 6,465,961 and 6,634,770 (LED lighting), not the '582 patent. I therefore cannot confirm any CAFC 2026 appeal involving 11,219,582, and I will not speculate one exists.

Bibliographic data (per the patent record)

Lineage: The '582 patent is a continuation of 15/627,906 (now US 10,646,419), itself a continuation of 14/710,416 (US 9,789,036), itself a continuation of 12/329,582 (US 9,295,619), which is a continuation-in-part of 11/307,463 (US 2007/0183987 A1). Because the effective filing date traces to 2006-02-08, the term ends in 2026 — consistent with the "anticipated expiration 2026-02-08" entry.

Assignment nuance: The record lists Jensen as inventor but shows assignments to CAO Group, Inc. from both Steven D. Jensen and Densen Cao, Dr. (effective dates in May 2015). A third-party aggregator (patentleaderboard.com) lists this patent under "Steven D. Jensen — Ultradent Products," which conflicts with the patent's own assignment record naming CAO Group. I'd treat the CAO Group assignment as authoritative.

Abstract (verbatim)

"The present invention is a formable dental treatment tray utilizing poly(2-ethyl-2-oxazoline) and a gelatinous active. Blending of the active is accomplished by mixing the Poly(2-ethyl-2-oxazoline) with an active ingredient, such as a peroxide like hydrogen peroxide, carbamide peroxide, sodium perborate, or sodium percarbonate, usually also with water or an appropriate organic solvent. Peroxide concentrations in these new gels can reach a 30% concentration of hydrogen peroxide while maintaining a shelf life of six months at room temperature without developing peroxide decomposition. The gels are applied to an appropriate backing and dried to a gelatinous state. In use, the active is hydrated and regains adhesiveness. Then the tray is pressed and formed around a user's dental arch to form the customizable tray. Multiple active ingredients may be used, with or without peroxide, for accomplishing desired treatment regimens."

The claims: plain-language overview

The patent has exactly two claims, both independent (no dependent claims):

Claim 1 — the basic dried gel-on-strip device

1. A strip of backing material that is flexible and planar, with two flat sides.
2. A dental composition applied to at least part of one flat side.
3. The composition contains three things: (a) a peroxide bleaching agent, (b) a solvent, and (c) a thickening agent — where the thickener is at least one member of the Markush set consisting of polyethyloxazoline and polyvinylpyrrolidone (PVP).
4. The composition has been dried until it is no longer fluid.
5. The dried composition must be gelatinous, non-coalescent, and visco-elastic, such that when stuck to a user's dental arch, both the composition and the backing flex and conform to the arch without cracking or breaking.

In plain terms: a flexible strip coated with a peroxide gel that has been dried to a gummi-like, non-merging, rubbery film, which stays stuck to the teeth and bends with them rather than snapping.

Claim 2 — the same device with an explicit shelf-life/storage limitation
Claim 2 repeats every element of Claim 1 and adds a functional limitation on the dried composition. It must be gelatinous, non-coalescent, and visco-elastic:

• during storage in a package at room temperature for up to six months, and
• after removal from the package and adhesion to the dental arch,

such that the composition and backing together flex and conform to the particular irregularities of the user's arch without cracking or breaking.

In plain terms: Claim 1 plus a promise that the product is stable on the shelf for six months and still conforms to an individual's irregular tooth contours after opening.

Observations on claim scope:

• The claims recite "polyethyloxazoline," not the specification's "Poly(2-ethyl-2-oxazoline)" — the shorthand and the parenthetical IUPAC-style name are used interchangeably in the disclosure.
• PVP is expressly claimed as an alternative thickener, though the specification describes it as less preferred ("While it is not as preferred as Poly(2-ethyl-2-Oxazoline), polyvinylpyrrolidone ('PVP') may be used in this invention with good results").
• The "set ... consisting of" language makes the thickener a closed Markush group — only polyethyloxazoline and PVP are covered, not equivalents outside the set.
• Neither claim recites a specific peroxide concentration, molecular weight, viscosity, or drying temperature; those appear only in the specification (e.g., 30% H₂O₂ with six-month room-temperature stability; viscosity 1,000–200,000 cP; 200,000 M.W. poly(2-ethyl-2-oxazoline) in a 6:4 ratio with 50% H₂O₂).

The specification's seven worked examples run from 11% to 27% carbamide peroxide (and one 11% hydrogen peroxide) with 33–50 wt% poly(2-ethyl-2-oxazoline) at 200,000 or 500,000 M.W.

Litigation landscape (district courts, not CAFC)

Google Patents' litigation panel and the Stanford NPE database tie the '582 patent to multiple district-court actions brought by CAO Group, all asserting the same five-patent whitening portfolio (10,602,259; 10,646,419; 11,219,582; 11,826,444; 11,826,445):

• CAO Group v. The Individuals ... Identified on Schedule A, No. 1:24-cv-01211 (N.D. Ill., filed Feb. 12, 2024) — Schedule-A e-commerce defendant case.
• CAO Group v. Walmart / related Utah actions, Nos. 2:24-cv-00175 and 2:24-cv-00498 (D. Utah) — Walmart stipulated to dismissal with prejudice.
• CAO Group v. Karaka LLC (d/b/a The DoubleY Brands), No. 1:24-cv-04903 (N.D. Ill.) — voluntarily dismissed Dec. 18, 2024.
• CAO Group, Inc. v. Ivoclar Vivadent, Inc., No. 1:25-cv-01430 (D. Del., filed Nov. 24, 2025).
• CAO Group Inc v. GuruNanda, LLC, No. 8:25-cv-02074 (C.D. Cal., filed Sep. 12, 2025).

I found no indication of any appeal of these matters to the Federal Circuit as of this date.

Uncertainty flags (stated explicitly, not fabricated)

1. No CAFC 2026 docket for '582 was found. I cannot confirm an appellate proceeding exists; if one does, it did not surface in my searches.
2. The 2025-03-11 Certificate of Correction appears in the legal events, but I do not have its content and cannot say what was corrected.
3. The maintenance-fee lapse and the 20-year term expiry both fall in early 2026, so the "Expired – Fee Related" status reflects an expired patent; enforceability of past-infringement damages claims is a separate legal question I am not opining on.
4. Inventorship/assignment discrepancy between the patent's assignment record (CAO Group) and third-party aggregator data (Ultradent) — noted above; the assignment record should control.

I'll search for litigation involving US Patent 11,219,582 using the sources you specified.

Let me gather details on the additional cases identified.

Litigation Involving U.S. Patent No. 11,219,582

Patent identity (verified, literal): U.S. 11,219,582 B2 — "Peroxide gel composition." Application No. 16/784,582, filed Feb. 7, 2020; granted Jan. 11, 2022; priority date Feb. 8, 2006; current assignee Cao Group, Inc. (West Jordan, Utah); inventor Steven D. Jensen. Status per Google Patents/Patexia: expired — fee related (lapse for failure to pay maintenance fees, Feb. 16, 2026).

I conflated nothing with similar numbers: I excluded unrelated hits such as UK company number 11219582 ("75 Music Limited") and Docket No. 25-1011 (Supreme Court/Dolby brief), which are not this patent.

Cases identified

Patents asserted alongside the '582 patent

• GuruNanda (8:25-cv-02074): Exhibits show the complaint attaches the '259, '419, '582, '444 and '445 patents.
• Ivoclar (1:25-cv-01430): Report to Commissioner lists 10,602,259; 10,646,419; 11,219,582; 11,826,444; 11,826,445.
• Walmart (2:24-cv-00175): US10602259, US11826445, US11826444, US10646419, US11219582.
• Ranir (2:24-cv-00498): US10603259, US10646419, US11219582, US11826444, US11826445 (declaratory judgment).

Important qualifications

1. Ground truth vs. training data. Per your rule, I prioritized search results. Two sources conflict on the §1,25-cv-01430 status: Ex Parte shows "Status: Closed," while the PACER docket confirms ongoing activity through April 2026 (answer Mar 13, MTD Apr 2, pro hac motions Apr 8). I report the docket activity as the more reliable indicator that the case remains live.

2. Aggregator scope. The Stanford NPE Litigation Database lists only two cases for patent 11,219,582 (1:25-cv-01430 and 1:24-cv-01211), while Google Patents' family-litigation panel and Patexia show additional Utah, Northern District of Illinois and Central District of California matters. The narrower NPE count may reflect that database's focus on NPE-asserted patents; CAO is a practicing entity, so several matters appear outside that dataset.

3. Unconfirmed item. Case 1:24-cv-05129 (N.D. Ill.) appears only in the Google Patents family-litigation list. I was unable to retrieve a docket or party detail, so I flag it as unverified rather than assert a plaintiff/defendant/filing date.

4. Sealed / Schedule A cases. Because 1:24-cv-01211 (and likely 1:24-cv-05129) are Schedule A TRO actions, the defendant list is long, partially pseudonymous e-commerce sellers, and filings may be sealed — details such as exact filing dates and outcomes may not be publicly complete.

5. No CAFC or Supreme Court appeal identified. No Federal Circuit appeal of any '582 judgment appears in the results; the Dolby/USIJ certiorari material that surfaced is unrelated to this patent.

If you want, I can attempt targeted PACER/docket pulls for 1:24-cv-01211 and 1:24-cv-05129 to confirm the Schedule A defendants and dispositions, and verify the closing documents in the Ranir and Walmart Utah actions.

I'll verify the "no proceedings" default against live sources before writing this up.

PTAB / AIA Trial Landscape — US 11,219,582 ("Peroxide gel composition"), Cao Group, Inc.

Verified against the structured "PTAB proceedings on file" block (USPTO ODP, no AIA trial proceedings returned) plus independent web searches conducted 2026-09-28 for IPR/PGR/CBM filings naming the '582, and for the related family members '259, '419, '444, '445.

Proceedings overview

Zero AIA trial proceedings. The USPTO Open Data Portal returns no IPR, PGR, or CBM involving US 11,219,582, and my independent searches surfaced none — so the breakdown is 0 active / 0 claims invalidated / 0 claims sustained / 0 settled / 0 institution denials. No PTAB estoppel attaches to anyone, no claim has been canceled, and the patent's two independent claims (claim 1 and claim 2) are each still "untested" — but the more important fact for a defendant today is that the '582 lapsed for failure to pay its 3.5-year maintenance fee, effective 2026-01-11 (see caveat below). The real defensive posture is not "hardened by surviving IPRs" — it is "never stress-tested at the Board, expired on the maintenance-fee docket, and now being litigated only in district court."

⚠️ Verification caveat, stated plainly: the absence of PTAB activity is a negative finding. I confirmed it via the structured ODP block and searches of PTAB petition/decision repositories and PTAB dockets, but I could not run a query directly against PTAB E2E or PTAB API in this session. Treat "no proceedings" as high-confidence but not court-certified. A docket pull at PTAB E2E using the patent number and the family numbers is the 5-minute confirmation step.

No proceedings exist to bullet out. Rather than fabricate sections, the substantive invalidity-related activity is set out below — clearly labeled as not AIA trials.

Analogous invalidity activity (NOT AIA trials — no estoppel effect)

2:24-cv-00498-RJS — Ranir LLC v. Cao Group, Inc. (D. Utah, filed 2024-07-16)

• Type: Declaratory judgment action (non-infringement + invalidity) — a substitute for an IPR, not an IPR.
• Asserted patents challenged: '259, '419, '582, '444, '445.
• Ranir's invalidity theory: Ranir's own "oral care layer" (OCL) formulation and flat-sheet wrap delivery system, used since 2002 and described in U.S. Pub. No. 2004/0005277 (filed 2002-07-02), allegedly predates the '582's 2006-02-08 priority date. Ranir's complaint (¶¶65–68) also alleges Cao knew of this art by July 2023 via direct correspondence, and pleads inequitable conduct-flavored facts.
• Why this matters more than an IPR would: the '582's claim 1 requires a dried, gelatinous, non-coalescent, visco-elastic composition on a flexible planar backing with polyethyloxazoline or PVP as thickener — and PVP-based whitening strips on flexible backings have been commercially sold since well before 2006. Ranir is running that argument in court rather than at the Board.
• Source: Ranir complaint, D. Utah 2:24-cv-00498 (CourtListener/archive copy)

1:25-cv-01430 — CAO Group, Inc. v. Ivoclar Vivadent, Inc. (D. Del., filed 2025-11-24)

• Type: District court infringement action asserting the '259, '419, '582, '444, and '445 patents against Ivoclar's VivaStyle whitening strips.
• Status: Live. Ivoclar answered and counterclaimed on 2026-03-13; motion-to-dismiss briefing on the docket into April 2026. No IPR or PGR has been filed by Ivoclar despite a pending five-patent assertion and ample § 315(b) window.
• Source: NPE Litigation Database entry

1:24-cv-01211 (N.D. Ill., filed 2024-02) and 8:25-cv-02074 (C.D. Cal., filed 2025-09-12, GuruNanda)

• Schedule A / e-commerce defendant campaigns; defendants raised invalidity and prior-art (U.S. Pat. Nos. 5,891,453 and 5,894,017) arguments in opposition to preliminary injunctive relief, but again via district-court motion practice, not the Board. See Defendants' motion to vacate, N.D. Ill. 1:24-cv-01211, Dkt. 102.

Reverse-direction note (Cao as petitioner)

Cao Group has itself been an aggressive IPR petitioner — e.g., IPR2014-00796 and IPR2014-00450 against P&G's '569, '811, and '199 whitening-strip patents, and an ex parte reexam against Cao's own '961 patent by OSRAM. That is useful background (Cao knows the PTAB playbook and the prior art in this space) but creates no estoppel running against the '582, because estoppel under 35 U.S.C. § 315(e)(2) only binds petitioners against the patent they challenged. Cao-as-petitioner in 2014–2015 is irrelevant to a defendant's freedom to raise art against the '582 in 2026.

Strategic summary

Claim status of the '582. The patent issued with exactly two claims, both independent (claim 1 and claim 2; claim 2 adds a sustained-room-temperature-storage limitation), and neither has been canceled, narrowed, or adjudicated. There are no surviving-after-IPR claims to enumerate because no IPR ever issued an FWD. Note the patent does not claim priority-dependent narrowing via a reexamination certificate either — the only post-issuance PTO event on the file is a certificate of correction on 2025-03-11 (see Legal Events in the structured data), which corrects text but does not change claim scope materially. Practically, the entire asserted scope is six words away from the prior art: "thickening agent selected from the set consisting of polyethyloxazoline and polyvinylpyrrolidone (PVP)," plus the dried/gelatinous/non-coalescent/visco-elastic functional limitations. PVP-on-a-strip is old art; the invention's novelty lives entirely in the drying state and flex-without-cracking functional language — which is exactly where Ranir's and Ivoclar's non-infringement and invalidity theories are aimed.

Estoppel landscape. There is no § 315(e)(2) estoppel in existence on this patent — estoppel requires a petitioner, and there has never been one. That is genuinely good news for a defendant: every § 102/§ 103 ground, including printed publications and patents that Cao itself litigated against P&G's portfolio, remains available in district court. What does constrain a defendant is not IPR estoppel but (i) the ordinary district-court rules on late-amended invalidity contentions and (ii) the § 315(b) one-year bar, which runs from service of a complaint alleging infringement of the '582 — so a party served more than a year ago has lost the IPR option even though the patent is otherwise untouched. Also preserve the priority question: whether claim 1 is actually entitled to the 2006-02-08 date of U.S. App. Ser. No. 11/307,463, given the '582 was filed 2020-02-07 as a fourth-generation continuation, is a § 112 written-description argument that could move the effective date later and open up intervening art. That argument is live and untested by any tribunal.

Pattern signals. No petitioner has filed any IPR — not a single one — despite the patent being asserted against Ivoclar, Ranir/Perrigo, Walmart, GuruNanda, and dozens of Amazon sellers since 2023. That is an unusual pattern and it has a mundane explanation: Cao's targets are largely e-commerce sellers and consumer-product companies that either (a) cannot absorb a $500k PTAB campaign, (b) prefer the cheaper DJ route (Ranir), or (c) settle or get dismissed before trial (1:24-cv-04903 Karaka, voluntarily dismissed 2024-12-18; 5:22-cv-01874 P&G, dismissed 2022-11-14). No defensive aggregator has stepped in. The "Unified Patents" links in the Google Patents family-litigation block point to Unified Patents' litigation databank (portal.unifiedpatents.com/litigation/...) — that is a docket aggregator, not evidence that Unified Patents filed, funded, or joined an IPR against the '582. Do not read those links as aggregator involvement.

The expiry point, which dominates everything else. Per the structured data, the '582 lapsed for failure to pay maintenance fees — maintenance-fee reminder mailed 2025-09-01, lapse event 2026-02-16, with an effective lapse date of 2026-01-11 (the end of the 3.5-year grace period) — and Google Patents lists the "anticipated expiration" as 2026-02-08 (20 years from the 2006-02-08 earliest filing). Both paths converge: the patent is no longer enforceable as a matter of the current record, and it would have expired on its own terms within weeks anyway. One caveat a careful defendant should price in: a lapsed patent can be revived by petition for unintentional delay under 37 C.F.R. § 1.378, which would retroactively restore enforceability. Cao has not filed such a petition as of the last docket activity I can see, and revival would not restore any term beyond 2026-02-08 — but if your demand letter is dated after 2026-02-08, the appropriate response is a § 282/standing inquiry, not an IPR.

Recommended next steps

1. If you have been served, lead with the expiry, not validity. Request the maintenance-fee payment record from USPTO PatentCenter for US 11,219,582. If the 3.5-year fee remains unpaid and no § 1.378 revival petition has been granted, the '582 cannot support injunctive relief or post-expiry damages, and pre-expiry damages are limited by the six-year lookback in 35 U.S.C. § 286. A lapsed patent also cannot be asserted to exclude imports in an ITC § 337 action — a useful lever if you are an importer.

2. Do not spend money on an IPR unless you are inside the § 315(b) window and the enforcement posture justifies it. There is no PTAB proceeding to piggyback on, so an IPR would be a from-scratch campaign against two claims. Against an expired/lapsed patent the ROI is poor — the Board will still institute on an expired patent, but you gain no leverage over an injunction that no longer exists. Ex parte reexamination (37 C.F.R. § 1.510) is a cheaper alternative that leaves the challenger anonymous and, unlike IPR, is not barred by prior service.

3. Copy the Ranir record. The Ranir OCL prior art — the 2004/0005277 publication and the 2002-formulation evidence — is the strongest public invalidity package against the '582's PVP embodiment. It is already in a public complaint with exhibits; see 2:24-cv-00498, Dkt. 1. Because there is no IPR estoppel on the '582, you may raise it freely.

4. Watch the family, not just the '582. The '259, '419, '444, and '445 patents share a substantively identical specification and the same 2006-02-08 priority claim, and they are asserted alongside the '582 in the Ivoclar and Ranir matters. An invalidity or written-description ruling on the shared disclosure — especially on priority entitlement — would have cross-family effect. Any IPR filed against a sibling (none is on file as of this date) would be worth tracking for its collateral reasoning about the common specification.

5. If you want the PTAB option preserved. Confirm your service date on any complaint asserting the '582. Under § 315(b) you have one year from service; misses are absolute. If you are inside the window and Cao manages to revive the patent, an IPR on claim 1 under § 103 over PVP-strip art plus a secondary drying/visco-elasticity reference is the cleanest path — but the functional "non-coalescent / gelatinous / flexes without cracking" limitations will be the battleground, and you should expect Cao to argue those are not taught by any strip art of record.

Bottom line for a defendant: there is no PTAB history to exploit or fear — no claims canceled, no claims sustained, no estoppel. Instead you have three independent defenses that don't require the Board: the record shows the patent lapsed for non-payment of maintenance fees effective 2026-01-11 (subject to possible revival), its statutory term ran out on or about 2026-02-08, and the claims as written rest on PVP-on-a-strip art that a competitor has already put into a public district-court complaint.

I'll gather assignment and ownership data from the primary sources and cross-references before writing the analysis.

Key new leads: a CAO Group v. Procter & Gamble action, a "Sheer White!" TRO case, and a possible Dobbin IP Law correspondent. Let me dig into those and the assignment recording details.

I hit the tool-call limit while chasing the last three threads (the specific reel/frame images, the correspondent-of-record fields, and CAO Group's current corporate status). I'll flag precisely what I could and could not retrieve rather than fill gaps with inference.

Ownership Chain Reconstruction — US 11,219,582 B2 ("Peroxide gel composition")

Source basis: The USPTO Assignment Center record as surfaced through the patent's Google Patents legal-events panel (which mirrors Assignment Center's reel/frame, assignor, assignee, and effective-date fields), cross-checked against PACER dockets, the Stanford NPE Litigation Database, and CAO Group's own pleadings. I could not retrieve the Assignment Center correspondent-of-record field or the underlying assignment PDFs — see the honesty flags at the end. No assignment data below is invented; every reel/frame cited comes from the record.

Inventors

Unusual patterns — none of the fire-sale precursors:

• No inventor departure. Both Jensen and Cao remain tied to CAO Group as of the 2025–2026 filings assigned to CAO Group. There is no "all inventors left within 12 months" signal.
• Aggregator mis-attribution (flag). patentleaderboard.com lists US 11,219,582 on a page titled "Steven D. Jensen — 67 Patents at Ultradent Products." That conflicts with the patent's own recorded assignment (CAO Group). Aggregators typically cluster by first-listed assignee across an inventor's whole portfolio, so this is very likely a page-level grouping artifact — the USPTO assignment record controls: CAO Group, Inc.
• Contradiction with the previously generated summary: that section named Jensen as the sole inventor without noting Cao's role as an assignor of record or the family-level co-inventorship. Flagging it explicitly per instructions.

Original assignee

CAO Group, Inc., a Utah corporation, 4628 West Skyhawk Drive, West Jordan, Utah 84084.

• Primary line of business: dental and medical devices — LED dental curing lights, dental lasers, endodontic systems, cements, and tooth-whitening products. It is an operating manufacturer, not a licensing vehicle. Its general counsel of record has been Kelly Preece (per a 2012 CAO office action in app. 12/785,203); Densen Cao is the founder/principal inventor and named on dozens of CAO patents.
• Does it ship a product embodying the claims? Yes — and CAO said so in its own pleadings. In CAO Group, Inc. v. Karaka LLC, No. 1:24-cv-04903 (N.D. Ill.), CAO pleaded: "Plaintiff developed a product line which embodies Plaintiff's Patents, under the name 'Sheer White! Teeth Whitening Strips' … exclusively through its website (www.caogroup.com) and through its authorized distributor Henry Schein." The complaint further pleads that the patents are listed on the product packaging, with a URL at caogroup.com/patents mapping products to patents. Related product lines: Sheer DesenZ! desensitizing films and Sheer FluorX! fluoride films.
• Current status: Operating. It continues to prosecute and obtain patents as of 2025–2026 (assignee on US 12,392,655; US 12,396,823; US 12,478,799; and 2026 publications). It is a serial plaintiff in its own name. No bankruptcy, assignment for the benefit of creditors, or dissolution appears in any record I retrieved.
• Note: CAO Group is the original assignee named on the issued patent — this chain has never left home.

Assignment timeline

There are three recorded assignments, all from the individual inventors back to the original assignee — i.e., confirmatory/nunc pro tunc ownership cleanup, not transfers to a third party.

• 2015-05-20 (executed) / recorded 2021-10-30 — Reel 057970/0876

  • Conveyance: Assignment of assignor's interest
  • Assignor: Steven D. Jensen, Mr.
  • Assignee: CAO Group, Inc., Utah
  • Correspondent: Not retrievable from the sources accessible to me — the Assignment Center correspondent field did not surface in any indexed copy. Not a finding.
  • Context: Internal ownership perfection — inventor-to-employer assignment executed in May 2015 (three days after the 14/710,416 continuation was filed on 2015-05-12) but not recorded until during prosecution of the '582.

• 2015-05-29 (executed) / recorded 2021-10-30 — Reel 057970/0880

  • Conveyance: Assignment of assignor's interest
  • Assignor: Densen Cao, Dr.
  • Assignee: CAO Group, Inc., Utah
  • Correspondent: Not retrievable.
  • Context: Same cleanup, filed the same day as the Jensen recording; executed the same month as the Jensen assignment.

• 2015-05-29 (executed) / recorded 2022-01-06 — Reel 058585/0251

  • Conveyance: Assignment of assignor's interest
  • Assignor: Densen Cao, Dr.
  • Assignee: CAO Group, Inc., Utah
  • Correspondent: Not retrievable.
  • Context: A second, duplicate Cau-→CAO recording five months after the first, executed on the identical date (2015-05-29). Recorded roughly four weeks before issue and six days after the issue-fee payment (2021-11-30). Duplicate recordings of the same inventor/date pair are typically USPTO-driven corrections to cover additional applications or continuity-chain defects — not a new transaction.

Timing observation worth stating plainly: the recordings of 2021-10-30 fall 16 days after the 2021-10-13 Final Rejection in the '582 prosecution, and the 2022-01-06 recording falls after the 2021-11-23 Notice of Allowance. This sequencing is consistent with an examiner/ownership-verification requirement being satisfied to clear the case to allowance — a routine prosecution event, not a monetization event.

If Assignment Center holds no additional records beyond these three, state the consequence: the original assignee (CAO Group, Inc.) has owned this patent continuously since the inventors' 2015 executions. No assignment to any third party exists in the record.

Timeline diagram

timeline
    title Ownership of US 11219582
    2006 : Priority application filed by inventors
    2015 : Jensen assigns rights to CAO Group
         : Cao assigns rights to CAO Group
    2020 : Continuation application filed by CAO Group
    2021 : Assignments recorded at USPTO
    2022 : Patent issued Jan 11
         : CAO sues Procter and Gamble
    2024 : Schedule A suits filed in Illinois
    2025 : Suits against Ivoclar and GuruNanda
    2026 : Patent lapses for unpaid maintenance fee

NPE / troll-pattern signals

Additional pattern actually present (not on the checklist)

Mass-defendant "Schedule A" joinder and TRO practice. CAO Group, Inc. v. The Individuals … Identified on Schedule A, No. 1:24-cv-01211 (N.D. Ill., filed 2024-02-12), names a long list of Amazon/e-commerce storefronts (Fairywill, OETU Health, PURESELL, Trayknick, and dozens more). Related TRO activity appears in a 2025 matter captioned around "Sheer White!" (No. 25-cv-14512). This joinder/TRO methodology is statistically associated with NPE filings — but the asserter here is a practicing manufacturer protecting a product line it sells through Henry Schein and caogroup.com. Methodology is not identity; I am not scoring this as an NPE signal. It belongs in the file as a litigation-style observation only.

Also note the role reversal: CAO has been a defendant on the receiving end too — P&G sued CAO over the Crest Whitestrips patents (Procter & Gamble Co. v. CAO Group, Inc., No. 1:13-cv-00337, S.D. Ohio), and CAO petitioned for IPR on P&G's '199, '569 and '811 patents (IPR2014-00796/-00798, institution denied Dec 2014). CAO later sued P&G back on this portfolio (Cao Group, Inc. v. Procter & Gamble Co., No. 5:22-cv-01874, C.D. Cal., filed 2022-10-26; consolidated into 5:22-cv-00142 and dismissed). A company that litigates in both directions for two decades is an operating competitor, not a troll.

Verdict

Operating-company assertion.

Justification: The entire ownership chain consists of three inventor-to-employer assignments — Jensen at reel 057970/0876 (executed 2015-05-20, recorded 2021-10-30) and Cao at reels 057970/0880 (executed 2015-05-29, recorded 2021-10-30) and 058585/0251 (executed 2015-05-29, recorded 2022-01-06) — all naming CAO Group, Inc., the same Utah corporation that is the original assignee named on the face of the patent. That company sells a product embodying the claims ("Sheer White! Teeth Whitening Strips") through its own website and the distributor Henry Schein, pleads that fact in its own complaints, and the Stanford NPE Database labels it a "Product company." The recordings occurred during prosecution to perfect title, not within six months before any filing, and no third party ever acquired the patent; the patent lapsed for non-payment of maintenance fees effective 2026-01-11, not because it was monetized to a shell.

Verify at: USPTO Assignment Center — https://assignmentcenter.uspto.gov/ (search "11219582" or "16/784,582"); mirror — https://assignment.uspto.gov/patent/index.html. Legal-events cross-check: https://patents.google.com/patent/[US11219582B2](/patent/US11219582B2)/en.

Honesty flags — what I could not verify

1. Correspondent-of-record is missing for all three recordings. The Assignment Center correspondent field and the assignment PDFs did not surface in any indexed copy I reached. Signals #3 therefore reads unclear, not not present. Named candidate firms (Parsons Behle & Latimer; Dobbin IP Law, P.C.) are supplied as context only and are not evidence about these three reels. Anyone completing this diligence should open the three reel/frame PDFs directly.
2. Inventorship discrepancy unresolved. The '582 face names Jensen alone, yet Cao assigned to CAO for this case and CAO's pleadings call Jensen and Cao co-inventors of the sibling '444/'445 patents. I could not retrieve the '582's full 102/IDS inventor block or the Certificate of Correction to reconcile this.
3. Certificate of Correction dated 2025-03-11 — present in the legal events, content not retrieved. It could bear on claim text or on a named-data field. Unverified.
4. CAO Group's current corporate health is inferred from continuing 2025–2026 patent filings in its name; I found no SEC filings (CAO Group appears to be privately held) and no Articles-of-Dissolution-type record either way. "Operating" rests on the filings and the 2024 complaint's present-tense product allegations.
5. Contradiction with the prior section: the earlier summary listed Jensen as sole inventor without qualification and treated the CAO-vs-Ultradent aggregator conflict as a clean "CAO controls" call. Both are flagged above; the assignment record does control on ownership, but the Ultradent grouping and Cao's assignor status deserve the explicit caveats given here.

I'll research the prior-art citations for US 11,219,582 against the USPTO record and other sources.

Let me examine the examiner's cited references and the family-cited prior art more closely.

Prior-Art Analysis — US 11,219,582 B2 ("Peroxide gel composition")

Method, scope, and a threshold legal point

What I searched and what I could verity. I attempted a USPTO-record pull for application 16/784,582 and its citation lists. I was able to retrieve the Google Patents record for US11219582B2 (the authoritative text supplied to me) with its Citations (2) and Family Cites Families (27) tables, but I hit my live-search step limit before I could independently pull a scanned PTO-892 / "References Cited" form or the PACER docket from the USPTO PatentCenter directly. Everything below is therefore grounded in the citation tables of the patent record itself, with dates taken literally from that record. Where I am inferring a document's content from its title rather than from text I actually retrieved, I say so.

Only two references are of record as cited by the examiner in the '582 patent. The record shows the "×Cited by examiner" footnote only on these two:

1. US 2004/0241110 A1
2. US 2005/0186150 A1

The other 27 entries are "Family Cites Families" — i.e., references cited somewhere in the family (parent/related applications' IDS, and foreign search reports), not necessarily cited against the '582 application itself. I treat them separately below and flag them as family-level, not '582-level, art.

Governing law — this matters for the § 102 analysis. The '582 patent issues from an application filed 2020-02-07, but every claim traces to the 2006-02-08 priority date via an unbroken chain of continuations (15/627,906 → 14/710,416 → 12/329,582 → 11/307,463). No claim has ever had an effective filing date on or after March 16, 2013. Pre-AIA 35 U.S.C. §§ 102/103 therefore govern, and the critical date for § 102 art is 2006-02-08. Both examiner-cited references predate it comfortably. I analyze anticipation (not obviousness) because that is what you asked; where a reference only gets you to § 103, I say so rather than overstate.

Claim 1 element set (used throughout the mapping): (a) flexible, planar strip backing with two flat sides → (b) dental composition on ≥ part of one flat side → (c) peroxide bleaching agent + solvent + thickening agent, thickener ∈ closed Markush {polyethyloxazoline, PVP} → (d) dried until no longer fluid → (e) dried composition gelatinous, non-coalescent, visco-elastic, conforming with the backing to a dental arch without cracking or breaking.

Claim 2 = all of Claim 1 plus the dried composition must remain gelatinous/non-coalescent/visco-elastic during up to six months' packaged room-temperature storage and after removal, conforming to "the particular irregularities" of the arch.

A. Examiner-cited references (the core of your request)

A-1. US 2004/0241110 A1 — "Jelly-type tooth-bleaching patch"

Brief description. A "jelly-type" tooth-bleaching patch comprising (claim 1) a film, an adhesive applied on the film, and moisture-proof wrapping paper adhered on the adhesive. The adhesive is a multi-component system: peroxide (hydrogen peroxide, carbamide peroxide, calcium peroxide, sodium percarbonate, sodium perborate, etc.) + peroxide stabilizer + tartar inhibitor + coating‑forming agent + coating-forming aid + wetting agent + plasticizer. Critically, the coating-forming agent is expressly selected inter alia from polyvinyl pyrrolidone (PVP) (and polyvinyl alcohol, PVP-H₂O₂ homopolymer, etc.). Solvent is purified water/ethyl alcohol. The patch is kept moist/jelly via glycol wetting agents — its whole point is a "poultice"-like adhesive that slowly releases H₂O₂ into saliva.

Claim mapping — what it hits and what it misses:

§ 102 conclusion for Lee: Lee is the closest compositional reference — it discloses the peroxide + solvent + PVP combination on a flexible film backing, i.e., element (c) including the claimed PVP Markush member. But it does not anticipate claim 1 or claim 2 because it fails the "dried to an extent that it no longer remains in a state of fluidity" limitation and the "gelatinous, non-coalescent, visco-elastic … without cracking or breaking" limitation. Lee's jelly is the opposite of the claimed dried state. Lee's best use is therefore as § 103 art (e.g., combined with a "substantially solid / dried" teaching such as Allred below).

A-2. US 2005/0186150 A1 — "Dental bleaching devices having a protective adhesive region"

Brief description. Dental bleaching devices in the shape of a tray, strip, or patch comprising: a barrier layer (moisture-resistant polymer, thin and flexible so it conforms to teeth); a dental bleaching composition; and a protective adhesive composition. Two teachings are directly on point for the '582 claims:

1. Dried-gel-to-solid processing. "[S]ubstantially solid bleaching compositions are manufactured by first forming a bleaching gel having a substantial quantity of a solvent and then removing some or all of the solvent by evaporation to yield a substantially solid composition" ([0067]/[0015]). "Substantially solid" is defined as a cohesive mass that does not readily flow — i.e., no longer fluid.
2. Worked example 1 (this is the crucial one): a composition of 16% carbamide peroxide + 38% polyvinyl pyrrolidone (PVP, M.W. = 1.3 million) + 46% water, spread as a gel over flexible polymer sheets, heated 50–70 °C for ~1 h, and further dried overnight, yielding a "substantially solid, coherent bleaching composition on the surface of the polymer sheets," which is then cut into smaller pieces and used as strips or shaped into tray-like devices. The composition also "become[s] more adhesive to teeth when moistened with saliva or water." The reference further discloses a sealed package (claim 23; FIG. 3/10; [0023], [0106]) and polymer barrier layers explicitly including wax, paraffin, EVA, polyethylene, PET ("MYLAR"), polyurethane, etc.

Claim mapping:

§ 102 conclusion for Allred: Allred is the single most relevant reference for the device claimed in the '582 patent, and in my assessment is the better § 102 candidate than Lee, because it alone supplies elements (a)–(d) — including the drying-to-non-fluid step — with PVP as the disclosed thickener and carbamide peroxide as the bleaching agent. Its weakness for a strict § 102 case is element (e): Allred frames the dried state as a "substantially solid" coherent mass, whereas claim 1 demands a "gelatinous, non-coalescent, visco-elastic" body that flexes without cracking or breaking. Whether those are the same state is a factual/claim-construction question. If they are treated as equivalent, Allred anticipates at least claim 1 (as to the PVP/carbamide-peroxide embodiment). Claim 2 is not anticipated by Allred, because Allred discloses sealed packaging but no six-month room-temperature stability limitation.

B. Family-cited references (27) — family-level art, not '582-examiner art

These come from the "Family Cites Families (27)" table. Caution: these were cited somewhere in the family (parent IDS's / foreign search reports), not necessarily against the '582 claims. I list dates and a description; where I mark a reference "§ 102 candidate," I mean for the '582 claims if it were applied, based on its title/known subject matter — not that it was so applied. I flag where I am inferring content from the title only.

C. Bottom line — which claims are potentially anticipated, and by whom

1. Claim 1 —

• Allred (US 2005/0186150 A1) is the strongest § 102 reference: it discloses a flexible strip/patch barrier layer, a carbamide-peroxide + water + PVP bleaching composition, dried by evaporating solvent to a substantially solid, non-flowing state on flexible sheets (Example 1, 50–70 °C), cut into strips, with sealed packaging. It maps onto every claim-1 element; the only genuine dispute is whether Allred's "substantially solid / coherent" state equals the claimed "gelatinous, non-coalescent, visco-elastic … without cracking or breaking" state. If a tribunal treats those as the same property, claim 1 is anticipated; if not, Allred is § 103 art.
• Lee (US 2004/0241110 A1) discloses elements (a), (b), and (c) — including PVP and peroxide on a film — but expressly keeps the composition wet/jelly. It therefore cannot anticipate claim 1's drying and visco-elastic limitations; it is § 103 art.

1. Claim 2 — Not anticipated by either examiner-cited reference. Neither Lee nor Allred discloses the six-month packaged room-temperature stability limitation plus post-removal conformity. The closest family-level art on the stability sub-issue is AU 2002/314772 (peroxide stabilization) and the hydrogel references (US 8,840,918 / US 8,206,738), but those are compositional/stabilization art, not a disclosure of the claimed device at that stability. Claim 2 is best attacked, if at all, under § 103 (e.g., Allred or Lee + a peroxide-stabilizer teaching).

2. Which reference is "most relevant"? For the claimed device as a whole, Allred (US 2005/0186150 A1) — it is the only reference of record that combines a flexible strip backing, a peroxide + PVP + solvent composition, and a drying-to-non-fluid manufacturing step. For the specific thickener chemistry (polyoxazoline with an oxidant), the family-level US 4,144,211 A (Dow) is the most technically pointed, though it is not a dental reference.

D. Explicit uncertainty flags (no fabrication)

1. I could not retrieve the scanned PTO-892 for 16/784,582 in this session (search step limit reached). The two "examiner-cited" references are taken from the record's Citations (2) table (both flagged "× Cited by examiner"); I did not independently confirm the examiner's § 102/§ 103 characterization or the "considered but not cited" art.
2. The 27 family-cited references are family-level, not '582-examiner-level. I have marked them as such. Several (notably #1 Dow, #22–24 Ultradent, #18–19 hydrogels, #20 peroxide stabilizer) are plausibly § 102/§ 103-relevant to the '582 claims, but I have not verified that any was applied against the '582 claims or that its disclosure reaches the specific limitations.
3. Dates are quoted literally from the patent record. Where a "priority" and a "publication" date differ I have given both; for entries where the record gives only one date line, only that one is shown.
4. Entry #27 (US 2009/0130624 A1, priority 2007-11-20) post-dates the 2006-02-08 priority date and is therefore not available as § 102 prior art against the '582 claims — I include it only for completeness of the family table.
5. The 2025-03-11 Certificate of Correction in the legal events could in principle touch the claims; I do not have its content and cannot assess whether it affects claim scope or the prior-art analysis. Treat any claim-scope statement here as subject to that unknown.
6. Content of family references marked "(title-only)" (e.g., JP H06239912, US 6,080,889, US 6,113,629, CA 2470463) is described from the record's titles; I did not open those documents in this session, so the one-line descriptions are characterizations, not verified quotations.

If you want, in a follow-up I can pull the actual PTO-892 and the file-wrapper "References Cited" for application 16/784,582 and for its immediate parents 15/627,906 and 14/710,416, to confirm whether the two cited references were the only art considered and to check the examiner's stated rejections.

I'll ground this §103 analysis in the actual prior-art references listed on the patent page, verifying key disclosures where I can.

Obviousness Analysis — U.S. Pat. No. 11,219,582 B2 ("Peroxide gel composition")

Task: Assess whether claims 1 and 2 of US 11,219,582 are obvious under 35 U.S.C. § 103 over the prior art identified in the "Prior Art" section of the patent record (Citations, Family Cites Families, Similar Documents), and identify specific combinations with articulated motivations.

Caveat up front: what follows is technical/legal analysis, not a validity adjudication. Invalidity must be proven by clear and convincing evidence to a factfinder. Where I rely on art not listed on the '582 page, I say so explicitly.

1. Framework and the level of ordinary skill

The Graham v. John Deere factors control: scope and content of the prior art, differences between the prior art and the claims, the level of ordinary skill, and objective indicia. KSR Int'l Co. v. Teleflex Inc., 550 U.S. 398 (2007), adds that a claimed combination is obvious where it is "a combination of familiar elements according to known methods" yielding predictable results, or where there was "a finite number of identified, predictable solutions" to a known problem — a case of "obvious to try."

Effective date. The '582 claims priority through a four-generation continuation chain to US 11/307,463 (filed 2006‑02‑08). If that chain holds, the prior-art cut‑off is Feb. 8, 2006. If it does not — and the written-description question flagged in the PTAB section of this analysis is genuinely open, given that PVP-thickener subject matter and the "non-coalescent / visco-elastic" functional language must each be supported in the 2006 parent — then the '582 (filed 2020‑02‑07) opens onto fourteen additional years of strip art, including the PVP-tissue-adhesion work Ultradent itself filed in mid‑2006. That is a material asymmetry: the § 103 case below is strong on a 2006 cut-off, and becomes overwhelming on a 2020 cut-off.

Proposed POSITA construct: a formulator with a B.S. in chemistry, pharmacy, or materials science (or a D.D.S. with formulation experience) and 3–5 years developing oral-care gels, films, and whitening strips, familiar with the water-soluble polymer toolbox (carbomers, PVP, PEO, cellulosics) and with strip/patch device architectures. I state this as my construct; no tribunal has fixed it.

2. The claim elements to be met

Both claims are independent; claim 2 adds a storage-and-use functional limitation. Reduced to a chart:

Two structural observations matter for the obviousness posture:

• L3 is a closed Markush group containing PVP. Under settled practice, if a single member of a claimed Markush genus is obvious, the genus claim is obvious. The PVP embodiment is therefore the claim's soft underbelly — and the '582 specification concedes it works: "While it is not as preferred as Poly(2-ethyl-2-Oxazoline), polyvinylpyrrolidone ('PVP') may be used in this invention with good results." That sentence is an admission that the PVP species involves no unexpected result.
• L5's "non-coalescent" term is definitionally empty once L4 is met. The '582 specification itself defines a "fluid" as a substance that "conform[s] and coalesce[s]… within 10 minutes," and says a "gelatinous compound… will not coalesce." Anything dried out of fluidity is, by the patent's own definition, non-coalescent. So L5 collapses into L4 plus inherent visco-elastic behavior.

3. Prior art inventory (all from the '582 record unless noted)

(a) Strip-on-flexible-backing art — saturates L1, L2, L3 (peroxide/solvent), L6

• US 5,894,017 (P&G) — verified text and claims: a strip "having a flexural stiffness less than about 50 grams/centimeter… readily conformable without permanent deformation," carrying an oral-care substance that "provides adhesive attachment," the substance "preferably in the form of a gel," on a 0.013 mm low-density polyethylene film, optionally with shallow pockets. US5894017
• US 6,136,297 / 5,879,691 / 6,045,811 / 6,582,708 (P&G family) — e.g., '297 claim 6 ("said substance is a gel"), claim 8 (teeth-whitening actives), claim 15 (carboxypolymethylene, i.e., Carbopol), claim 17 (polyethylene film). justia 6136297
• US 6,514,483 (Colgate) — "Strip for whitening tooth surfaces" (2001).
• US 8,652,446 (LG Household & Healthcare) and ES 2320321 T3 — whitening patches.
• US 8,840,918 and 8,206,738 (Singh/Feldstein, A.V. Topchiev Inst. / Corium Int'l; 2001 priority) — verified: a composition of a water-swellable, water-insoluble polymer, "a blend of a hydrophilic polymer and a complementary oligomer," a peroxide whitening agent, and a backing member; the hydrophilic polymer expressly being a poly(N-vinyl lactam) — i.e., PVP. Classified at A61K8/8176 ("Homopolymers of N-vinyl-pyrrolidones"). US8840918; FPO mirror; related US 9,084,723 (PDF).

(b) The "dried-then-moistened" gelatinous layer — carries L4 and L5 bodily

• US 6,997,708 B2 (Allred/Jessop, Ultradent; filed Dec. 5, 2003; issued Feb. 14, 2006) — listed on the '582 page under "Similar Documents." Verified text: a strip or patch with a "substantially solid adhesive layer" formed from an intermediate composition "heated to drive off the solvent"; the layer "has increased adhesiveness to oral tissue when moistened with saliva or water"; Example 1 dried the coated sheets at 50–70 °C, produced a "solid, coherent, non-flowable" bleaching layer on polyethylene/paraffin/MYLAR sheets, cut them into strips, and reported that upon moistening the strips "conform[ed] to the natural irregularities of the dental arch and adhere[d] firmly against the teeth." Claim 31: "contained within a sealed package prior to use." US6997708; PDF
• US 7,011,523 B2 (Ultradent) — "Bleaching compositions and devices having a solid adhesive layer and bleaching gel adjacent thereto" (same architecture, bleaching agent).
• US 2004/0241110 A1 (Sang-Ho Lee; published Dec. 2, 2004) — an examiner-cited reference. Verified: a "jelly-type tooth-bleaching patch" comprising "a film, an adhesive applied on the film, and a moisture-proof wrapping paper adhered on the adhesive." The adhesive comprises peroxide (H₂O₂, carbamide peroxide, sodium percarbonate, inter alia) + coating-forming agent, and the coating-forming agent is expressly "polyvinyl pyrrolidone" (also PVA, sodium alginate). Examples 3 and 4 use PVP at 0.5 wt% and 10 wt% on a PET film; the patch "is flexibly attached to teeth in accordance with the teeth shape." US20040241110; PDF
• US 2005/0186150 A1 / US 7,192,280 B2 (Allred) — dental bleaching devices with a protective adhesive region.
• US 7,056,118 / 7,059,857 / 6,860,736 / 2005/0255054 (Ultradent); US 2006/0029908 A1 — thin flexible barrier + endoskeletal/solid adhesive treatment compositions.
• US 6,503,486 B2 / US 2002/0187111 A1 (located outside the '582's own citation lists — flagging that divergence): a dry, solvent-cast, hydratable poly(ethylene oxide) film containing a solid peroxide (e.g., sodium percarbonate; Example 1 gives M.W. 200,000 PEO, dried overnight to a ~160 µm film at ~3.4% H₂O₂ equivalent), with a barrier coating on one face, cut into strips and packaged, that "when hydrated by saliva… or prewetted by dipping the strip in water will adhere to the teeth." US 6,503,486 PDF; US 2002/0187111 A1 PDF

(c) Polyoxazoline-specific art

• US 4,144,211 (Dow Chemical, 1979) — "Novel complexes of polyoxazolines or polyoxazines and halogens, interhalogens or pseudo-halogens and process for preparing same." This is the only oxazoline-specific reference in the '582's own cited-family list. It establishes that polyoxazolines were known as polymers that form complexes with strong oxidizing halogen species — useful for showing the polymer's chemistry with oxidants was explored, but it teaches complexation, not thickening, and it is not a peroxide reference. Honest limitation: the '582 record contains no reference that expressly identifies poly(2-ethyl-2-oxazoline) as a thickener for a peroxide gel. I searched for one and did not obtain a citable source in this session. That gap is almost certainly why the examiner allowed the claims.

(d) Motivation-bearing disclosures inside the prior art

• US 6,997,708, Example 2 (verified): poly(ethylene oxide) "was a satisfactory tooth adhesion agent" but "was less satisfactory in promoting adhesion between a solid bleaching layer and a polymer sheet."
• US 6,997,708, Example 3 (verified): with Carbopol 974P, "the intermediate composition… shrunk considerably… Shrinkage… caused the polymer sheet to become partially shriveled up. Whereas shriveling of the polymer sheet was not desired…"
• US 2004/0241110, [0058] (verified): the jelly patch releases H₂O₂ into saliva at ~10% the level of a dry-type patch and holds peroxide in contact "at least three times longer than… a gel-type strip," directly motivating the shift from fluid gels to a coherent, dried/semi-dried layer.
• US 5,894,017 describes the same problem set the '582 Background recites: run-off, saliva wash-out, poor fit.

4. Specific § 103 combinations

Combination A — the PVP embodiment (claims 1 and 2): Lee '110 + Ultradent '708 (+ optionally P&G '017)

References: US 2004/0241110 A1 (Lee) as primary; US 6,997,708 B2 (Allred, Ultradent) as secondary; US 5,894,017 as tertiary for the strip geometry.

Mapping:

• L1/L2 — Lee: "a film, an adhesive applied on the film"; explicitly applied on a PET film and depicted in its FIG. 2. P&G '017 supplies the flexible, planar, conformable strip with rounded corners.
• L3 — Lee: peroxide (H₂O₂ / carbamide peroxide / sodium percarbonate) plus PVP as the coating-forming agent, with water/ethanol solvent. This is a literal read on the peroxide + solvent + PVP thickener combination.
• L4/L5 — Ultradent '708: a peroxide adhesive layer cast on a flexible polymer sheet and dried until "solid, coherent, non-flowable," which the patent's own Background disparages in the prior art as "brittle." Moistening restores tack. Gelatinous/non-coalescent/visco-elastic follows from the '582's own definitions once L4 is met.
• L6 — Ultradent '708 Example 1: strips "conform[ed] to the natural irregularities of the dental arch" — nearly the verbatim language of claim 2.
• Claim 2's packaging limit — Lee claim 1: "moisture-proof wrapping paper adhered on the adhesive"; Ultradent '708 claim 31: "contained within a sealed package prior to use."

Rationale (MPEP 2143(A), (C), (F)): Combining known elements (PVP-gelled peroxide adhesive + a dried, saliva-activated adhesive layer on a flexible film) according to known methods, to achieve the known and predicted result of a non-runny, saliva-resistant whitening strip. Both references address the same recognized defect — fluid gels wash out and dilute. Where the prior art already teaches that a peroxide adhesive layer can be dried on a film and re-activated by moisture, and separately teaches PVP as the coating-forming agent in a peroxide jelly on a film, the combination is not merely obvious to try — it is a substitution of one known water-soluble polymer for another in a known device, with a reasonable expectation of success.

This combination alone likely disposes of both claims, because striking the PVP species strikes the entire closed Markush group.

Combination B — the polyethyloxazoline embodiment (claim 1): P&G '017/'297 + Ultradent '708 + Dow '211 (+ extrinsic evidence of oxazoline polymer properties)

Mapping: P&G supplies L1/L2/L3(peroxide+solvent+gelling agent) and the flexural-stiffness/conformability language; Ultradent '708 supplies L4/L5/L6; Dow '211 supplies the oxazoline-specific teaching that polyoxazolines are water-soluble polymers whose chemistry with strongly oxidizing species was known and studied; and the '582's own Background supplies the admission that the known thickener set for peroxide gels is "CARBOPOL, silica, PVP, and polyethylene glycols" — i.e., a small, finite, enumerated set of water-soluble polymers from which the formulator was choosing.

Rationale (MPEP 2143(B), (E), (F)): A simple substitution of one known water-soluble, nonionic, film-forming, hygroscopic polymer for another, in a device and method already known to work with that class. KSR's "finite number of identified, predictable solutions" fits precisely: the '582 itself enumerates the field, and the claimed result (a hygroscopic, tacky-when-wetted, flexible dried gel) is the expected behavior of that polymer class.

Weakness to price in: I cannot cite art in the '582 record expressly naming poly(2-ethyl-2-oxazoline) as a peroxide thickener. Cao will argue (i) Dow '211 teaches away, because complexation with halogens suggests the polymer is consumed by oxidants; and (ii) there is no suggestion specifically pointing to oxazolines. On (i), the Federal Circuit test requires the reference to "criticize, discredit, or otherwise discourage" — '211 does not discuss peroxides and does not disparage their use with polyoxazolines. On (ii), the gap is real and would require either extrinsic evidence (Aquazol-type product/technical literature, oxazoline polymerization art such as the cited JPH 06239912A) or a priority challenge that opens 2006–2020 art.

Combination C — Topchiev/Corium hydrogels as an alternative primary: US 8,840,918 + US 8,206,738 + any strip reference

Mapping: these disclose a peroxide-containing, backing-member-mounted, self-adhesive hydrogel whose hydrophilic polymer is a poly(N-vinyl lactam) — PVP — and which the specification states need not use dental trays. Combined with P&G '017 for the flexible planar strip geometry, this reads on L1–L3 directly and, with mild drying, on L4–L6.

Rationale: a known technique (crosslinked/blended PVP hydrogel with plasticizer) applied to a known device (whitening strip) to improve the same property both references pursue — adhesion without leaking into the oral cavity. Also useful as a § 102 anticipation argument, since the hydrogel is described as a "solid composition and self-adhesive."

Combination D — the "dried hydratable film" line: US 6,503,486 / US 2002/0187111 + Lee '110 (+ Ultradent '708 Example 2 as motivation)

Mapping: the PEO family teaches a dried, solvent-cast, hydratable peroxide film with a barrier layer, cut to strips and packaged — L1, L2, L4, and much of L6. Lee teaches PVP as the film-/coating-forming polymer with peroxide. Substituting PVP for PEO in the film is the whole of L3.

Motivation — and this is the cleanest one in the record: Ultradent '708's Example 2 expressly reports that PEO "was less satisfactory in promoting adhesion between a solid bleaching layer and a polymer sheet." A POSITA seeking to keep the dried-film architecture but fix its adhesion to the backing is directly pointed toward an alternative film-forming, water-soluble, tack-producing polymer — precisely Lee's disclosure. That is a teaching, suggestion, or motivation grounded in the prior art itself, not hindsight.

(Flag: US 6,503,486 / US 2002/0187111 are not on the '582's own citation lists; I verified their disclosures from the source PDFs cited above. They should be independently confirmed before reliance.)

5. Why a POSITA would have been motivated to combine — the general rationales

1. Common problem, common field. The '582 Background is, itself, a recitation of the prior art's stated problems: run-off, saliva dilution, pump-out during biting, strip movement on uneven teeth, and brittle dried compositions that crack. The references are drawn from that same field and target the identical defects.
2. Predictable result. Water-soluble PVP and poly(2-ethyl-2-oxazoline) are both hygroscopic, nonionic, film-forming, gel-forming polymers. A dried layer of either on a flexible film will be tacky when wetted and will flex with the film. Nothing in the claims requires an unpredictable property except the six-month, 30% H₂O₂ stability figures, which the claims do not incorporate (claim 2 recites only "gelatinous, non-coalescent, and visco-elastic" during storage — a state, not a decomposition rate).
3. Express design pressure in the art. Ultradent '708's Examples 2 (poor PEO adhesion to the backing) and 3 (Carbopol shriveling the flexible sheet) supply a documented, unmet need for a better thickener/adhesion polymer — exactly the need the '582 asserts it meets.
4. KSR's "obvious to try." The specification enumerates the known alternatives — "CARBOPOL, silica, PVP, and polyethylene glycols" — and asserts that poly(2-ethyl-2-oxazoline) outperforms them. Selecting and testing a small, identified set of known polymer thickeners in a known strip platform is the paradigm case of obvious to try.
5. Claimed scope is not commensurate with the asserted advantage. Under In re Kao and Pfizer v. Apotex, where a patentee asserts unexpected results across a genus, the showing must be commensurate in scope. The '582 asserts a six-month, 30% H₂O₂ result — but claim 2 covers any peroxide, any solvent, any concentration, and both thickeners, and the specification admits PVP "may be used… with good results." The PVP half of the genus is supported by nothing unexpected.

6. Counterarguments Cao will raise, and how they fare

7. Bottom line

• Claims 1 and 2 are, in my assessment, vulnerable to a § 103 challenge — most sharply on the PVP aspect of the Markush group, which is fatal to the claims as a whole. Combination A — US 2004/0241110 A1 (Lee) in view of US 6,997,708 B2 (Allred/Ultradent), with US 5,894,017 (P&G) for strip geometry — maps every limitation of both claims, including claim 2's "particular irregularities" and "in a package" language, using only references already of record on the '582 page (Lee is an examiner citation; '708 and '523 appear under "Similar Documents"). Lee supplies peroxide + solvent + PVP on a film with moisture-proof packaging; '708 supplies the dried, non-flowable, moisture-reactivated, arch-conforming layer.
• The polyethyloxazoline embodiment is the harder half. No reference in the '582's own record expressly teaches poly(2-ethyl-2-oxazoline) as a peroxide-gel thickener. A challenger needs extrinsic evidence of that polymer's known water-soluble/gel-forming/tackifier properties, or — better — a successful challenge to the 2006 priority claim, which would make the entire 2006–2020 body of PVP/PEO/PVP-hydrogel strip art available and moot the gap.
• The "non-coalescent / visco-elastic / gelatinous" limitations add little. By the '582's own definitional scheme, a composition dried out of fluidity is non-coalescent by definition. The functional language is a restatement of the drying step, not a separate inventive contribution.
• The six-month storage limitation in claim 2 is not a saving limitation. It is a result-effective, expected property of a hygroscopic dried gel in a sealed package — and the sealed-package element is already claimed in Ultradent '708.

Interaction with the earlier sections of this analysis: this § 103 assessment reinforces two points already made — (i) the claims were never tested at the PTAB, so there is no § 315(e)(2) estoppel preventing any defendant from running these grounds in district court; and (ii) the strongest public invalidity package in the record remains the Ranir declaratory-judgment complaint (2:24-cv-00498, Dkt. 1), which targets the PVP embodiment with pre-2004 oral-care-layer art and which now aligns with the examiner-cited Lee reference. Against a patent that lapsed for non-payment effective 2026‑01‑11 and whose 20-year term ran out on or about 2026‑02‑08, the practical question is not whether the claims are obvious — it is whether anyone has a live damages period worth invalidating them over.