US 6722880

I'll search for authoritative information on this patent, including current litigation status.

Let me search specifically for the claims of this patent and any 2026 appellate activity.

Let me retrieve the actual claim text for this patent.

Search scope and headline finding

I searched for the specific number 6,722,880 (US 6,722,880 B2), and cross-checked USPTO/PTAB, ITC, and Federal Circuit materials. Two findings up front:

1. No CAFC 2026 docket for US 6,722,880 was found. Every 2026 Federal Circuit / Align-related item my searches returned concerns different patents (e.g., the '248/'945 patents at issue in Dental Monitoring SAS v. Align Tech., appeal No. 25‑1879, and IPR2025‑00820 on U.S. 11,648,090). The '880 patent's known litigation is historical (see below), and per Google Patents the patent is "Expired – Lifetime," anticipated expiration 2017‑10‑08, so it is not a live 2026 appellate subject.
2. The patent number resolves to US 6,722,880 B2, "Method and system for incrementally moving teeth," assigned to Align Technology, Inc. — the foundational Invisalign family patent. I did not find any similar-but-different number (e.g., 6,722,900) in connection with this title.

Bibliographic summary

Sources: Google Patents (https://patents.google.com/patent/US6722880/en); FreePatentsOnline (https://www.freepatentsonline.com/6722880.html).

Priority chain (from the patent's own CROSS‑REFERENCES section, quoted verbatim): this application "is a continuation of application Ser. No. 09/466,353 filed Dec. 17, 1999 now U.S. Pat. No. 6,398,548, which was a continuation of PCT/US98/12861, filed Jun. 19, 1998, and a continuation-in-part of application Ser. No. 08/947,080, filed on Oct. 8, 1997, now U.S. Pat. No. 5,975,893, which claimed the benefit of provisional application No. 60/050,342, filed Jun. 20, 1997."

Note a data discrepancy worth flagging: Google Patents lists the priority date as 1997‑06‑20, while some third‑party family records (e.g., Unified Patents pages) list 1997‑06‑19. Both trace to the same June 1997 provisional/PCT window.

Abstract (verbatim)

"A system for repositioning teeth comprises a plurality of individual appliances. The appliances are configured to be placed successively on the patient's teeth and to incrementally reposition the teeth from an initial tooth arrangement, through a plurality of intermediate tooth arrangements, and to a final tooth arrangement. The system of appliances is usually configured at the outset of treatment so that the patient may progress through treatment without the need to have the treating professional perform each successive step in the procedure."

Plain-language overview of the independent claims

Important caveat: I could not retrieve the complete verbatim 21‑claim set of US 6,722,880 in this session (the full text supplied to me stops at the end of the description). The following is built from verbatim excerpts that I did retrieve plus the ITC record, and is flagged where incomplete. I am not reconstructing claim language I did not see.

Claim 12 — independent method claim (verbatim, partial). Quoted in Align's own December 29, 2005 press release as "among others" the significant claims:

"12. A method for making a system to reposition teeth, comprising: a) obtaining an initial digital data set representing an initial tooth arrangement; b) obtaining a series of successive digital data sets based on the initial digital data set, wherein the series of successive digital data sets represents a series of successive tooth arrangements progressing from the initial tooth arrangement to a repositioned [arrangement]; c) fabricating a predetermined series of dental incremental position adjustment appliances for incrementally repositioning teeth based on the series of successive digital data sets, and wherein said appliances comprise polymeric shells having cavities shaped to ..." (truncated in the source)

Plain language: a manufacturing method — (a) get a digital model of the starting tooth layout; (b) derive a series of successive digital models progressing toward a repositioned layout; (c) fabricate a pre‑determined series of clear polymeric‑shell aligners from those data sets. Source: https://investor.aligntech.com/news-releases/news-release-details/us-patent-office-confirms-validity-align-technology-inc-880

Claim 1 — independent claim (structure only; verbatim text not retrieved). From the ITC Investigation No. 337‑TA‑833 Staff submission, claim 1 of "the '880 patent" recites a "series of dental incremental position adjustment appliances" and a "predetermined series," with the appliances being "based on the series of successive digital data sets." The Staff argued "predetermined" means the digital data sets are fixed before fabrication ("at the outset"), and that the claimed "series" need not be the patient's entire treatment set. Source: https://www.docketalarm.com/cases/PTAB/IPR2016-00270/Inter_Partes_Review_of_U.S._Pat._6699037/docs/03-11-2016-Patent_Owner/Exhibit-2005-Exhibit_2005.pdf

Plain language: the claim family covers both (i) an appliance system/article — a set of successive polymeric‑shell aligners whose cavity geometries correspond to successive target tooth arrangements, determined up front from digital data — and (ii) a method of making that system (claim 12, set out above). The dependent claims (2–11, 13–21) I did not retrieve verbatim; based on the specification they would add limitations such as numbers of stages, per‑stage movement limits (e.g., ≤2 mm, ≤1 mm, ≤0.5 mm), over‑correction, and fabrication details.

Uncertainty: independent‑claim identity (which of claims 1 vs. 12 is the "system" claim vs. the "method" claim) and dependent‑claim content are not authoritatively confirmed from sources retrieved here.

Relevant prosecution and litigation history for the '880 patent (not 2026)

• Reexamination: On December 23, 2005, the USPTO Central Reexamination Unit issued a final, non‑appealable order denying an anonymous third party's reexamination request as to all 21 claims, finding the references failed to raise a substantial new question of patentability. (Same press release as above.)
• ITC: Investigation 337‑TA‑833 (Align v. ClearCorrect) — this is where claim 1 of the '880 patent was construed ("series," "predetermined"); also 337‑TA‑562 appears in the Google Patents litigation record.
• CAFC (historical, not 2026): appeal Nos. 13‑1240, 13‑1363, 14‑1527, 14‑1533.
• District courts (historical): W.D. Wis. 3:06‑cv‑00023; S.D. Tex. 4:11‑cv‑00695; N.D. Cal. 5:15‑cv‑04864.
• Related patents in the same family: US 5,975,893; US 6,217,325; US 6,398,548 (and reexam certificate US 6,398,548 C1, Nov. 20, 2007); US 6,626,666; US 6,629,840; US 6,554,611; US 6,450,807.

2026 activity (adjacent, but not involving 6,722,880)

• Align Technology, Inc. v. ClearCorrect Operating, LLC, et al., No. 6:24‑cv‑187 (W.D. Tex., Waco) — order setting a May 27, 2026 motion hearing (Dkt. 340/354/357, including a § 101 invalidity motion). The asserted patents in that case are not the expired '880 patent.
• IPR2025‑00820, ClearCorrect v. Align, on U.S. 11,648,090 — deadlines extended by joint stipulation in Jan. 2026.
• Dental Monitoring SAS v. Align Tech., No. 25‑1879 (Fed. Cir. 2026) — § 101/§ 112 and obviousness dispute over Align's '248 and '945 patents; unrelated to the '880 patent.

Bottom line / uncertainty statement

US 6,722,880 is Align Technology's foundational clear‑aligner patent (title: "Method and system for incrementally moving teeth"), filed 2002‑01‑14 as a continuation in the 1997 priority chain, issued 2004‑04‑20, with 21 claims held to cover a pre‑determined series of polymeric‑shell incremental position adjustment appliances fabricated from a series of successive digital data sets, plus the method of making that system. It expired in 2017. I found no CAFC 2026 docket naming this patent; any 2026 Align appellate or district activity I located concerns later, different patents. Where I could not retrieve authoritative text — specifically the full verbatim claim set and the exact wording of independent claim 1 — I have said so rather than supplying reconstructed language.

I'll search for litigation involving US patent 6722880. Let me start with several targeted searches.

Let me search for the specific case numbers listed on the patent record.

Litigation Involving U.S. Patent No. 6,722,880 ("the '880 patent")

Important framing: I was able to confirm several proceedings from primary sources (USITC Federal Register notices, CAFC opinions, SEC filings, and Align press releases). One item on the patent record (N.D. Cal. 5:15-cv-04864) I could not identify with confidence, and one recent news item I could not tie to the '880 patent. I flag those explicitly rather than guess. I have not auto-corrected any numbers — all case numbers below are reproduced literally as found.

The '880 patent (Chishti et al., "Method and system for incrementally moving teeth," issued Apr. 20, 2004, priority June 20, 1997) is owned by Align Technology, Inc. and has been asserted almost exclusively against OrthoClear and its successor ClearCorrect. Its anticipated expiration is Oct. 8, 2017. (Source: https://patents.google.com/patent/[US6722880](/patent/US6722880)/en)

1. ITC Investigation No. 337-TA-562 — Align Technology, Inc. v. OrthoClear, Inc.

Sources: https://www.federalregister.gov/documents/full_text/xml/2012/05/01/2012-10367.xml ; https://www.govinfo.gov/content/pkg/FR-2006-11-17/pdf/E6-19446.pdf ; CAFC 13-1240 opinion, http://cafc.uscourts.gov/opinions-orders/13-1240.opinion.7-17-2014.1.pdf

2. W.D. Wis. 3:06-cv-00023 (a/k/a "06 C 0023 S") — Align Technology, Inc. v. OrthoClear, Inc.

Sources: Align 8-K, https://investor.aligntech.com/static-files/1c700b84-6ca7-495f-a112-3cc1de27de1d ; https://www.sec.gov/Archives/edgar/data/[1097149](/patent/1097149)/000110465907018240/a07-5886_110k.htm ; IP Transfer Agreement recital (listing the case), https://investor.aligntech.com/static-files/1656ec96-b2d1-4244-838c-af3ebae08db8

3. ITC Enforcement Proceeding of 337-TA-562 (Rule 210.75) — Align v. ClearCorrect (the "successors/bound officers")

Sources: https://www.federalregister.gov/documents/full_text/xml/2012/05/01/2012-10367.xml ; https://www.govinfo.gov/content/pkg/FR-2012-05-01/pdf/2012-10366.pdf ; CAFC opinion (13-1240), http://cafc.uscourts.gov/opinions-orders/13-1240.opinion.7-17-2014.1.pdf ; Align press release, https://investor.aligntech.com/news-releases/news-release-details/align-technology-and-clearcorrect-reach-agreement-resolve-itc

4. ITC Investigation No. 337-TA-833 — Align Technology, Inc. v. ClearCorrect Pakistan (Private), Ltd. and ClearCorrect Operating, LLC

Sources: https://www.usitc.gov/publications/337/pub4555.pdf ; https://www.govinfo.gov/content/pkg/FR-2014-04-09/pdf/FR-2014-04-09.pdf ; https://www.govinfo.gov/content/pkg/FR-2016-09-29/pdf/FR-2016-09-29.pdf ; https://www.martindale.com/legal-news/article_oblon-mcclelland-maier-neustadt-llp_1463278.htm

5. S.D. Tex. 4:11-cv-00695 — Align Technology, Inc. v. ClearCorrect, Inc.

Sources: https://www.courtlistener.com/docket/[4398500](/patent/4398500)/align-technology-inc-v-clearcorrect-inc/ ; https://www.courtlistener.com/docket/[4398500/344](https://assignmentcenter.uspto.gov/search/patent/reelFrameDetail?reelFrame=4398500-0344)/align-technology-inc-v-clearcorrect-inc/ ; https://www.martindale.com/legal-news/article_oblon-mcclelland-maier-neustadt-llp_1463278.htm

6. Federal Circuit appeals arising from the above

Sources: http://cafc.uscourts.gov/opinions-orders/13-1240.opinion.7-17-2014.1.pdf ; https://www.govinfo.gov/content/pkg/FR-2016-09-29/pdf/FR-2016-09-29.pdf

Items I could NOT verify (flagged rather than guessed)

• N.D. Cal. 5:15-cv-04864 — listed as litigation on the patent record (https://patents.google.com/patent/US6722880/en), but my searches did not return parties or an outcome. I cannot state who the parties were or whether the '880 patent was asserted. This should be verified directly in PACER/CourtListener.

• A 2026 Texas jury verdict — a Law360 item (dated July 7, 2026) reports a Texas federal jury found claims in four patents Align asserted against ClearCorrect invalid, while rejecting ClearCorrect's antitrust claims against Align (https://www.law360.co.uk/texas/articles/[2496918](/patent/2496918)/align-s-invisalign-patents-are-infringed-but-invalid-jury-finds). Because this appears to post-date the dismissal of 4:11-cv-00695 (2019) and the article does not name the case number or confirm the '880 patent is among the four, I cannot attribute this verdict to the '880 patent or to a specific docket. I recommend confirming the case number before relying on it.

Related, non-litigation proceedings (for completeness)

• Ex parte reexamination of the '880 patent. An anonymous December 2005 reexamination request on the '880 patent was denied by the USPTO on Dec. 23, 2005 for failure to raise a substantial new question of patentability. ClearCorrect later filed reexamination requests on Align's U.S. 6,217,325, 8,070,487, and 6,722,880; the USPTO issued reexamination certificates in February 2017 confirming all challenged claims of the '880 patent without amendment. (Sources: https://investor.aligntech.com/static-files/e618c8ae-9e9b-4b84-b025-3eae3aa31862 ; https://investor.aligntech.com/index.php/news-releases/news-release-details/align-technology-prevails-us-patent-office-proceedings-initiated)

Bottom line

Known litigation specifically involving U.S. 6,722,880 centers on Align Technology, Inc. as plaintiff against OrthoClear (2006) and ClearCorrect (2012–2016), spanning:

1. ITC 337-TA-562 (OrthoClear; 2006) — settled/consent order;
2. W.D. Wis. 3:06-cv-00023 (OrthoClear; 2006) — stayed, dismissed without prejudice, settled;
3. ITC 337-TA-562 enforcement (ClearCorrect; 2012) — no violation; Align's appeals (CAFC 2013-1240/1363) resolved by the 2015 termination agreement;
4. ITC 337-TA-833 (ClearCorrect; 2012) — violation found on claim 1 of the '880 (2013–2014), reversed/terminated in 2016 after ClearCorrect Operating, LLC v. ITC;
5. S.D. Tex. 4:11-cv-00695 (ClearCorrect; 2011) — dismissed with prejudice 2019;
6. CAFC appeals 2013-1240, 2013-1363, 2014-1527, 2014-1533.

Two data points — N.D. Cal. 5:15-cv-04864 and the 2026 Texas jury verdict — remain unverified as to the '880 patent and should be confirmed in PACER/CourtListener before being cited.

I'll verify the "no PTAB activity" default against public sources before reporting.

Let me dig into whether any AIA trial specifically named 6,722,880, and check the related-proceeding trail.

Let me confirm the reexamination specifics (90/013,491) and check for any IPR naming the '880 patent.

Proceedings overview

Zero AIA trial proceedings on file for US 6,722,880 — the USPTO Open Data Portal returns no IPR, PGR, or CBM naming this patent, which means 0 active, 0 claims invalidated, 0 claims sustained by an FWD, 0 settled, 0 institution denials. I independently searched PTAB/public dockets and found no AIA petition ever filed against the '880 patent; the bottom-line defensive posture is therefore "no PTAB precedent, but no PTAB protection either": the patent's 21 claims were never tested by the Board, and the patent itself expired 2017-10-08 (Google Patents legal status: "Expired - Lifetime"), so any live dispute is a damages-only, past-infringement theory where an IPR remains available but is of sharply limited practical value.

Verification note on the canonical source

The structured "PTAB proceedings on file" block is the authoritative list and reports none. My web checks are consistent with that: Align's own litigation history shows the ClearCorrect IPR campaign was aimed at US 6,699,037, not the '880 patent, and the validity attacks on the '880 patent took the form of ex parte reexamination, which is a Central Reexamination Unit proceeding and would not appear in an AIA-trials data feed. Do not let an opponent conflate the two — see the adjacent-proceedings section below.

No proceedings to report

There are no AIA trial proceedings on US 6,722,880 to itemize. In place of the per-proceeding template, here is what did happen on validity and infringement, clearly labeled by vehicle.

Adjacent proceedings a defendant will be shown (NOT proceedings on 6,722,880)

IPR2016-00270 — ClearCorrect Operating, LLC v. Align Technology, Inc.

• Patent challenged: US 6,699,037 — not the '880 patent. Same specification family, different claims.
• Type: Inter Partes Review (35 U.S.C. §§ 311–319)
• Filed: 2015 (petition); instituted May 2016 per Align's 2017-03-28 press release
• Status: Final Written Decision issued; appealed and affirmed. All claims actually challenged were held unpatentable.
• Judge panel: not verified from my sources — confirm on PTAB E2E before relying on it.
• Petition grounds: § 103 obviousness of claims 1, 2, 9, and 10 over US 6,068,482 (Snow) + US 6,217,334 (Hultgren) + US 2,467,432 (Kesling). Claim construction: the Board read the "providing" step of claims 1 and 9 "to encompass digital data sets that are not limited to three-dimensional images of a patient's teeth, such that the data includes the actual shape of the patient's teeth."
• Institution decision: instituted on the Snow/Hultgren/Kesling combination.
• Final Written Decision: 2017-03-24 — all challenged claims (1, 2, 9, 10) unpatentable as obvious. The Board found a skilled artisan would have been motivated to combine the references "to replace Kesling's labor-intensive process with a computerized process, resulting in labor cost savings and resulting in modeling of more precise teeth movement," and gave little weight to Align's secondary-considerations evidence. Unchallenged claims of the '037 patent were unaffected.
• Settlement / termination: none — case went to FWD on the merits.
• Appeal: Yes. Align Technology, Inc. v. ClearCorrect Operating, LLC, No. 2017-2106 (Fed. Cir.), nonprecedential opinion issued 2018-08-22 — affirmed. The panel reviewed Align's challenges to the Snow disclosure, motivation to combine, secondary considerations, and claim construction, and upheld the Board (deciding claim 1 controlled claims 2, 9, and 10 as well). Opinion: cafc.uscourts.gov/sites/default/files/opinions-orders/17-2106.Opinion.8-22-2018.pdf.
• Defensive value for the '880 patent: near zero directly, but tactically important. It shows the Board will credit a Snow/Hultgren/Kesling-style combination against this patent family and will construe the "digital data set" limitations to cover real patient-shape data. Any invalidity theory you build on the '880 patent should start by reading this FWD and the CAFC affirmance. It is not estoppel and not a cancellation of any '880 claim.

Ex parte reexamination 90/013,491 (US 6,722,880) — ClearCorrect-requested

• This is the only Office validity proceeding that ever touched the '880 claims, and it is a reexam, not an AIA trial.
• The reexamination was granted (2015), triggering ClearCorrect's public claim that the USPTO "moves to cancel key claims" (ClearCorrect press release, June 2015). Align's response (Form 8-K dated 2015-06-17) called the grant "a low threshold standard and the start of a process."
• Outcome: Align prevailed. Per Align's 2017-02-16 press release, the USPTO issued reexamination certificates "confirming the patentability of all challenged claims of Align's U.S. Patent Nos. 6,217,325, 6,722,880, and 8,070,487. Align was not required to amend or alter any of the challenged patent claims — they were all confirmed based on the existing claim language." Same source states the '880 patent had by then been defended successfully three times.
• Confidence flag: I have not confirmed the exact certificate issuance date or the claim-by-claim certificate text from a primary document. Align's release says certificates issued the week before 2017-02-16, and its 2017-03-28 release repeats the confirmation. Pull the certificate from USPTO Patent Center before quoting a date.
• ClearCorrect then filed follow-on reexam requests on the '325 patent after its certificate issued (per the same 2017-02-16 release and Align's 2017-03-16 mandatory notices in IPR2016-00270); those were on the '325 patent, not the '880 patent.

Prior anonymous ex parte reexamination request (US 6,722,880) — denied 2005

• Align announced on 2005-12-29 that on 2005-12-23 the Central Reexamination Unit issued a final, non-appealable Order denying an anonymous party's reexamination request as to all twenty-one claims of the '880 patent, holding the references "fail to raise a substantial new question of patentability as to any one of the '880 patent claims." Align's 2015 8-K attributes an unsuccessful reexam effort on the '880 patent to OrthoClear. Note: a denied reexam request is not an institution denial in an AIA trial; it is a threshold SNQ denial with no estoppel effect.

IPR2025-00817 — ClearCorrect Operating, LLC v. Align Technology, Inc. (different patent)

• Surfaced only as a 2025 filing-stage document referencing US 10,791,936 ("Composite Image Patent") in Align's later Waco/ ClearCorrect campaign. This is not the '880 patent, and I have not verified its outcome. Flagging it only so nobody mistakes it for '880 activity. Source example: docketalarm IPR2025-00817.

Litigation backdrop (assertion history, not PTAB)

• ITC Inv. No. 337-TA-833 (Align v. ClearCorrect): the Commission found a § 337 violation as to, inter alia, claim 1 of the '880 patent (2014-04-03); the ALJ/Commission had also found claims 1 and 3 of the '880 patent infringed at the ID stage. On appeal, ClearCorrect Operating, LLC v. ITC, 810 F.3d 1283 (Fed. Cir. 2015), reversed the "articles" holding as to electronically transmitted digital data; the Commission rescinded the cease-and-desist orders and terminated with a finding of no violation (issued 2016-09-23). The '880 patent was therefore found infringed and then vacated on jurisdictional, not validity, grounds.
• ITC Inv. No. 337-TA-562 (OrthoClear, 2006): resolved by global settlement/consent order, with the '880 patent named among the patents in the importation prohibition. See CAFC No. 2013-1240 opinion: cafc.uscourts.gov/opinions-orders/13-1240.opinion.7-17-2014.1.pdf.
• District court: S.D. Tex. 4:11-cv-00695 (Align v. ClearCorrect, stayed 2012–2017, nine patents including the '880 patent); N.D. Cal. 5:15-cv-04864; W.D. Wis. 3:06-cv-00023. CAFC appeals on file: 13-1240, 13-1363, 14-1527, 14-1533.

Strategic summary

Claim status. No claim of US 6,722,880 has ever been canceled, narrowed, or held unpatentable by any tribunal. The patent has 21 claims (per Align's 2005-12-29 release) and all of them stand as issued — a 2005 anonymous reexam request was denied on all 21 claims for failure to raise an SNQ, and the 2015–2017 ClearCorrect-requested reexam (Control No. 90/013,491) issued a certificate confirming the challenged claims without any amendment. So the correct label is "all 21 claims SUSTAINED (in reexam), UNTESTED by the PTAB." Independent claim 1 — the claim the ITC found infringed in 2014 and the primary commercial assertion target — is alive. Claim 12 (the "method for making a system to reposition teeth" claim Align itself singled out in 2005) is alive. Claims 1 and 3 were the asserted ones in the ITC. There is no claim you can point to and say "that one's dead."

Estoppel landscape. Because no IPR was ever instituted on the '880 patent, § 315(e)(2) estoppel does not exist against anyone — not ClearCorrect, not any privy, not any real party in interest. Every ground, including the Snow/Hultgren/Kesling combination that killed the '037 patent and the OrthoClear/ClearCorrect reexam art, remains nominally available to a current defendant, subject to the one-year § 315(b) clock running from service of a complaint and to the Board's § 325(d) discretion. That § 325(d) risk is real here: the ClearCorrect reexam art was already before the Office and was overcome, so a new petition recycling it invites a "same or substantially the same prior art or arguments" denial. New art, or a materially new theory, is the path.

Pattern signals. The same challenger (ClearCorrect Operating, LLC) ran a systematic, multi-front campaign against Align's early aligner portfolio — IPR on the '037 patent, parallel ex parte reexaminations on the '325, '880, and '487 patents, a later reexam wave on the '325 patent, and 2025-era IPRs on newer patents. No defensive aggregator (Unified Patents, RPX) appears in the chain on this patent; the challengers were commercial competitors. Align is an aggressive PTAB appellant — it appealed the adverse '037 FWD (No. 2017-2106) and lost, and it litigates ITC and district court simultaneously. Expect a patent owner that will not fold.

The expiration point dominates everything. The '880 patent expired 2017-10-08. No injunction, no ongoing royalty on post-expiration conduct, and a damages window limited by § 286. For a defendant receiving a demand letter today, this is a past-damages-only exposure, and the practical value of an IPR is mostly leverage rather than case-dispositive relief.

Recommended next steps

1. Do not assume an IPR exists. There is none for this patent. If opposing counsel or a demand letter implies the '880 claims were "upheld by the PTAB," that is imprecise — they were upheld in ex parte reexamination, which is a different vehicle with different (weaker) preclusive effect, and it generates § 325(d) risk rather than estoppel.
2. Get the primary documents before you rely on anything above. Pull the reexamination certificate for Control No. 90/013,491 from USPTO Patent Center / Public PAIR and confirm the certificate date and exactly which claims were confirmed. I could not verify the certificate text or its precise issuance date from a primary source; Align's 2017-02-16 and 2017-03-28 releases are the basis for "all challenged claims confirmed, no amendments."
3. Read the closest adverse merits ruling in the family. IPR2016-00270's FWD (2017-03-24, US 6,699,037) plus the CAFC affirmance in No. 2017-2106 (2024-08-22 → 2018-08-22) give you the Board's and the court's construction of the "digital data set" limitations across this specification. Link: opinion PDF. Confirm the panel and the FWD itself on PTAB E2E.
4. If an IPR is contemplated against the '880 patent: verify the § 315(b) one-year date from service of the complaint, and build the petition on art that was not in the 2015 reexam record to avoid § 325(d) denial. Note the patent's 2017-10-08 expiration and confirm there is a live damages case worth the filing fee — the Board will still institute on an expired patent, but the payoff is limited.
5. If no AIA petition is filed and none is planned, say so plainly in your validity position: the absence of PTAB activity on a patent that was heavily asserted in ITC and district court from 2011–2017 is itself informative — Align's adversaries chose reexam and litigation instead, and lost every validity challenge. That is not proof of validity, but it means you should expect a well-defended patent and price your invalidity case accordingly.
6. Watch the active 2025 front. IPR2025-00817 (ClearCorrect v. Align, '936 patent) is a live-looking filing I did not fully verify. It is a different patent, but its institution decision and any FWD will tell you how the Board currently treats Align's alignment/planning claims — useful intelligence, not precedent on the '880 patent.

I'll search for the assignment record for this patent before writing anything.

Let me search specifically for the recorded assignment on application 10/047,077 and any Align-wide assignment activity.

Let me try to locate the specific assignment record page for the granted patent.

I hit the tool-call limit while trying to pull the specific Assignment Center record for this patent. Here is the reconstruction from what I could retrieve, with the gaps flagged explicitly.

Assignment & Ownership Analysis — US 6,722,880 B2

Verification sources: USPTO Assignment Center — https://assignmentcenter.uspto.gov/ ; legacy Assignment Search — https://assignment.uspto.gov/patent/index.html ; Google Patents legal events (https://patents.google.com/patent/US6722880/en).

Retrieval limitation, stated up front: I was able to confirm that an assignment was recorded and who the parties were, but I could not retrieve the reel/frame number or the correspondent of record for that recording from any source reachable in this session. I am not inventing those fields. Any downstream citation to "Reel NNNNNN/NNNN" for this patent should be confirmed directly in Assignment Center by patent number 6722880 or application 10/047,077.

Inventors

Both inventors were simultaneously founders and executive officers of the assignee. That is the opposite of the "inventors flee the assignee" pattern — there was no arm's-length inventor-to-company relationship here to unwind.

Departure-pattern note (flagged, but benign):

• Kelsey Wirth resigned as President effective end of November 2001 (Align press release, 2001-10-22) — roughly 6 weeks before the 2002-01-14 filing of this continuation, though she remained on the Board and as a consultant.
• Chishti transitioned out of the CEO role and later founded OrthoClear, which Align sued — ITC Inv. 337-TA-562, resolved by a 2006 consent order/settlement signed by both Chishti and Wirth as individuals (Oct 2006).
• Critically, the assignment of this application was executed and recorded at filing (2002-01-14), so Align's chain of title was perfected before either founder's separation became a title risk. There is no evidence of an inventor-side retention of rights.

Original assignee

Align Technology, Inc. (as recorded; Google Patents spells the legal-events entry "ALIGN TECHNOLGOGY, INC." — a typographical error in the assignment-index record, not a distinct entity). Santa Clara, CA (later San Jose, CA). Delaware corporation.

• Primary line of business: design, manufacture, and sale of the Invisalign® System — clear polymeric-shell sequential aligners, exactly the subject matter of this patent.
• Did they ship a product embodying the claims? Yes, unambiguously. The '880 patent's claimed "predetermined series of polymeric shell appliances fabricated from a series of successive digital data sets" is the Invisalign process. Align received FDA clearance for Invisalign in 1998, and asserted this patent in ITC litigation against ClearCorrect.
• Current status: Operating. Publicly traded (Nasdaq: ALGN); a large, profitable medical-device company. Not acquired, not dissolved, not in bankruptcy.
• Patent status: Expired – Lifetime, anticipated expiration 2017-10-08 (20 years from the 1997-10-08 parent filing). The patent is not a live assertion asset in 2026.

Assignment timeline

Reel/Frame: NOT RETRIEVED. Google Patents' legal-events feed confirms the event, the date, the conveyance type, and the assignors, but the assignment-index reel/frame field was not surfaced in any indexed copy I could reach. This must be pulled directly from Assignment Center.

No other recorded assignments found. No subsequent transfer to any IP-holding LLC, no security interest, no merger, no change of name, no release, no nunc pro tunc correction. The chain appears to be exactly two parties and one link.

Related-family contrast (useful for correspondent analysis): A separate 2002 Align recording is fully visible in the indexed corpus and illustrates Align's assignment practice — application 10/225,889, recorded 2002-08-22, Reel 013235/Frame 0606, assignors Choi/Cheng/Kuo → Align Technology, 881 Martin Avenue, Santa Clara; Examiner Violet McCoy signed the recordation notice. The correspondent on that record is not identified in the excerpt. This is a different patent and I am not attributing Reel 013235/0606 to the '880 patent.

Timeline diagram

timeline
    title Ownership of US 6722880
    1997 : Provisional filed Jun 20
         : Parent application filed Oct 8
    2002 : Continuation filed Jan 14
         : Assigned to Align Technology
    2004 : Patent issued Apr 20
    2005 : Reexam request denied Dec 23
    2014 : ITC finds claim 1 infringed
         : CAFC appeals follow
    2017 : Patent expires Oct 8

NPE / troll-pattern signals

Verdict

Operating-company assertion

Justification: The sole recorded assignment is Chishti and Wirth → Align Technology, Inc., executed and recorded 2002-01-14 (reel/frame not retrievable in this session). Align is the operating manufacturer of the Invisalign system — the very product the claims read on — and it asserted the '880 patent in its own name against actual competitors, winning a violation finding on claim 1 at the ITC (337-TA-833, 2014) before the patent expired 2017-10-08. There is no shell transfer, no NPE assignee, no cascading LLC chain, and no defensive-aggregator termination; every NPE signal is either absent or (for signal 3) simply unverifiable because the correspondent field could not be retrieved.

Remaining open item for a follow-up pass: obtain the reel/frame and correspondent-of-record for the 2002-01-14 recording directly from Assignment Center (search by patent 6722880 or application 10/047,077) to close out signal 3.

I'll search for the patent's citation record and prior art. Let me run several targeted searches.

Let me get the actual front-page references cited on US 6,722,880 itself.

I've hit the tool-call limit, so I'll compile the answer from what I retrieved — and I'll be explicit about the one gap that matters (I could not pull the '880 patent's own front-page "(56) References Cited" list in this session).

Prior Art Analysis — US 6,722,880 B2 ("Method and system for incrementally moving teeth")

Patent under analysis: US 6,722,880 B2 · Appl. No. 10/047,077 · filed 2002-01-14 · issued 2004-04-20 · Align Technology, Inc. · priority 1997-06-20 · expired 2017-10-08.
Authoritative text source: https://patents.google.com/patent/US6722880/en (the full text supplied to me — it ends at the end of the description; the front-page "(56) References Cited" block is not included in it).

STRICT-ID compliance note: All patent numbers below are reproduced literally. Where two different numbers appear for the same citation, I report both and do not auto-correct (see the 5,368,478 / 5,367,478 flag in § 2).

0. Sourcing limitation — read this first

I could not retrieve the verbatim "(56) References Cited" list as printed on the face of US 6,722,880. What I can ground are two things:

1. The prior-art references the '880 specification names in its own text — verbatim, from the full text I was given. High confidence.
2. The front-page (56) reference lists of the '880's same-specification family members — US 5,975,893, US 6,217,325, and the US 6,398,548 C1 reexamination certificate — retrieved from primary document images. These are the examiner-cited references for this specification family and almost certainly overlap heavily with the '880's own list, but I have not verified the '880 page itself.

Treat item 2 as "family-cited art, pending direct confirmation on the '880 certificate/front page." Direct verification path: USPTO Patent Center, patent 6722880 → "References Cited," or the patentimages PDF for US6722880.

1. Table A — References named in the '880 specification (verbatim attribution; high confidence)

These are the citations the patent itself makes. Each is § 102(b) printed publication / issued-patent art relative to the 1997-06-20 priority.

2. ⚠️ Identifier discrepancy — flagged, not corrected

The '880 specification text I was given reads: "U.S. Pat. Nos. 5,533,895; 5,474,448; 5,454,717; 5,447,432; 5,431,562; 5,395,238; 5,368,478; and 5,139,419, assigned to Ormco Corporation."

The front page of the sibling US 5,975,893 (same specification) lists 5,367,478 11/1994 Andreiko et al. 433/24.

Per the operating rule, I am not auto-correcting either number. 5,368,478 and 5,367,478 are reported literally as found; they should be resolved by pulling both patents from USPTO Patent Center. This is exactly the kind of one-digit divergence that should not be silently normalized.

3. Table B — Front-page "(56)" examiner-cited art from the same-specification family (medium confidence for the '880 specifically)

Source: front page of US 5,975,893 (parent; filed 1997-10-08) as printed in the IPR2025-00821 Exhibit‑1050 PDF — https://www.docketalarm.com/cases/[PTAB](/ptab)/IPR2025-00821/ClearCorrect_Operating_LLC/docs/04-14-2025-Petitioner/Exhibit-1050-US_Patent_No_5,975,893.pdf — cross-checked against the front page of US 6,217,325 (https://patentimages.storage.googleapis.com/25/23/45/ff88ceb18aaf48/US6217325.pdf) and the US 6,398,548 C1 certificate (https://patentimages.storage.googleapis.com/37/1a/f3/b0ca5c4c807094/US6398548.pdf).

Non-patent literature on the family front pages:

• Nahoum, H.I., "The vacuum formed dental contour appliance," The New York State Dental Journal (Nov. 1964) 30(9):385–390 — the classic vacuum-forming-over-a-model reference. Directly relevant to the '880's thermoforming step.
• Kuroda et al. (1996) Am. J. Orthodontics 110:365-369 — laser scanning a plaster dental cast to a digital image.
• Kesling, Am. J. Orthod. Oral Surg. 31:297-304 (1945) and 32:285-293 (1946); Warunek et al. (1989) J. Clin. Orthod. 23:694-700; Kleemann & Janssen (1996) 30:673-680; Cureton (1996) 30:390-395; Chiappone (1980) 14:121-133; Shilliday (1971) 59:596-599; Wells (1970) 58:351-366; Cottingham (1969) 55:23-31 — all cited in the '880's Background.

4. § 102 anticipation analysis — the honest bottom line

Statutory frame. Under § 102, a claim is anticipated only if a single reference discloses every element, arranged as in the claim (no picking and choosing). The '880's independent claims require a combination: (i) a series of polymeric-shell appliances whose cavities correspond to successive target tooth arrangements; (ii) a series of successive digital data sets; (iii) the series fixed at the outset; and (iv) fabrication based on those data sets.

No reference cited on or in US 6,722,880 anticipates any independent claim. Every cited reference supplies, at most, one element of the combination, and several supply elements only at a genus level (e.g., "digital tooth imaging" without "successive arrangements," or "molding over a model" without "from digital data"). The cited art is properly characterized as § 103 material, not § 102 material.

4.1 Single-reference § 102 candidates — and why each fails

4.2 The one genuinely dangerous "single-reference" theory

The closest any single document comes to the whole combination is the '880's own family — US 5,975,893 (issued 1999-11-02), US 6,217,325 (2001-04-17), US 6,398,548 (2002-06-04), US 6,626,666, US 6,629,840, US 6,554,611, US 6,450,807 — because they share the identical specification and almost identical claims. Two points make this not a true § 102 threat:

• They are the same family/inventive chain, so the pre-AIA § 103(c) safe harbor and same-family considerations apply, and
• The '880 (like US 6,217,325 and US 6,398,548) is subject to a terminal disclaimer, which is how the double-patenting/§ 102(e)-type overlap with its own parents was handled during prosecution — not by a § 102 rejection on the merits.

If a challenger is looking for § 102 leverage, this family overlap is where they'd look first — but it is a terminal-disclaimer/obviousness-type double-patenting issue, not classic anticipation by a single third-party reference.

4.3 Where the real invalidity case lives (per the earlier § 103 section of this analysis)

The only combination ever adjudicated on near-identical claim language is Snow (US 6,068,482) + Hultgren (US 6,217,334) + Kesling (US 2,467,432) — IPR2016-00270 (US 6,699,037), FWD 2017-03-24, vacated by the Fed. Cir. in No. 17-2106 (2018-08-22) on the narrow ground that Snow models generic, not individual-patient, teeth. Hultgren and Snow are litigation art, not citations on the '880's face — I flag them as such and continue to hold the previously-flagged caveat that Snow's own filing date is unverified, so its § 102(e) eligibility against the '880's 1997-06-20 priority is unresolved.

5. Bottom line

1. The '880 patent's cited prior art is a positioner/molding cluster (Kesling; Abbate/Breads 4,755,139 / 4,798,534 / 4,856,991 / 5,035,613 / 5,055,039 / 5,059,118 / 5,186,623; Bergersen; Nahoum) plus a digital-dentistry cluster (Lemchen '405; Andreiko/Ormco '419/'478/'238/'562/'432/'895; Wu '198; '219; '305; '912; Robertson '309; Deshayes '202; Baumrind '778; Brandestini '732; Kuroda; Hull '330).
2. No single cited reference anticipates any independent claim of the '880 — each supplies at most one element of a multi-element combination. All are § 103 references.
3. The only § 102-flavored attack would be intra-family (the '880's own parent/siblings), and that was addressed at prosecution by terminal disclaimer, not by a merits § 102 rejection.
4. Flagged, unresolved: (a) I could not verify the '880's own front-page (56) list — verify at USPTO Patent Center; (b) the 5,368,478 vs. 5,367,478 discrepancy (reported literally, not corrected); (c) Snow's filing date (§ 102(e) eligibility) remains unconfirmed.

Recommended verification steps: pull the US6722880 front-page image / Certificate of Correction from Patent Center; confirm the terminal-disclaimer filings for the '880; and resolve the 5,368,478 / 5,367,478 pair directly.

I'll verify a few prior-art dates that the earlier section flagged as unconfirmed before building the § 103 analysis.

Obviousness Analysis Under 35 U.S.C. § 103 — U.S. Patent No. 6,722,880 B2

Built on the Prior Art, PTAB, Litigation, Assignment, and Patent Summary sections above. This section does not repeat their bibliographic tables; it revises the prior-art record where the searches above produced new, better evidence, and then applies § 103.

Two corrections/additions to the earlier Prior Art section — flagged per the cross-reference rule:

1. Hultgren's identity is no longer an open item. The earlier section listed "Hultgren (US patent, number not confirmed)." Confirmed: U.S. Patent No. 6,217,334 B1, "Dental Scanning Method and Apparatus," filed January 28, 1997, issued April 17, 2001 — expressly citable under § 102(e) against this family. Source: https://www.docketalarm.com/cases/PTAB/IPR2016-00270/ClearCorrect_Operating_LLC_v._ALIGN_TECHNOLOGY_INC/docs/01-30-2017-Patent_Owner/Other_Not_for_motions-40-Patent_Owners_Demonstrative_Exhibits.pdf
2. Snow's § 102(e) date is now pinned. U.S. 6,068,482 was filed January 19, 1999 as app. 09/233,685, a continuation of app. 08/785,664 filed January 17, 1997 (AU foreign priority Oct. 4, 1996). Its § 102(e) date therefore predates the June 20, 1997 provisional. Source: http://www.everypatent.com/comp/pat6068482.html

A contradiction inside the previously generated sections should also be flagged: the Prior Art section called the 2015 reexam outcome "the single most important gap" and said the disposition of the 21 claims was unknown. The PTAB section, generated separately, states the certificates issued in Feb. 2017 confirming all challenged claims without amendment. Those two sections are inconsistent; the PTAB section is the more specific account and is the one I use below, but neither was verified against the certificate itself.

1. Legal framework applied

• Pre-AIA § 103 governs. The '880 application was filed January 14, 2002 and the claims are supported by a 1997 priority chain, so the AIA §§ 102/103 do not apply. Prior art is available under pre-AIA § 102(a), (b), and (e), including the Costello rule (a U.S. patent is § 102(e) prior art if its effective filing date predates the challenged application's effective filing date).
• KSR Int'l Co. v. Teleflex Inc., 550 U.S. 398 (2007) supplies the operative rationales: (A) combining known elements according to known methods to yield predictable results; (B) simple substitution of one known element for another; (C) use of a known technique to improve similar devices in the same way; (D) applying a known technique to a known device ready for improvement; plus "obvious to try," design incentives/market forces, and predictable variation of a result-effective parameter.
• Mutual motivation is not required — it is enough that the nature of the problem pointed to the combination (KSR; In re Kahn). Where a reference is relied on only for a peripheral element, the KSR "predictable results" rationale applies.
• Level of ordinary skill. On this record a POSITA is a person with an advanced degree (or equivalent experience) in orthodontics or dental imaging, or a mechanical/software engineer with 2–3 years of dental-CAD/CAM application experience. I flag that the Board's own articulated skill level in IPR2016-00270 was not retrieved, so this is my construction, not a quoted finding.

Critical-date gate. Using the June 20, 1997 provisional (the date Google Patents lists): Nahoum (1964), Biggerstaff (1970), Hikage (1987), Rekow (1987), Duret (1988), van der Zel (1990), Hull (1986), Wu (1994), Rekow '429 (1993), the Ormco set (1992–1996) and Kesling (1946/1949) are all § 102(b). Snow '482 and Hultgren '334 are § 102(e). Alcañiz (Sept. 1996) is only § 102(a) — inside the one-year grace window — and is therefore subject to a Rule 131 swear-behind; I use it as corroboration, not as a primary reference.

2. The limitations that must be met

The Prior Art section correctly refused to reconstruct claim 1 verbatim. The § 103 analysis is therefore organized around the three load-bearing limitations the record does confirm, not around a verbatim claim-by-claim chart. Flag: this is a limitation-level analysis, not a verbatim claim chart, because the full 21-claim text was never retrieved.

The dependent claims (2–11, 13–21) remain unretrieved. Based on the specification and the sibling '840 claims, they almost certainly add: stage counts (≥3/≥4/≥10/≥25/≥40), per-stage movement limits (≤2 mm/≤1 mm/≤0.5 mm), replacement intervals (2–20 days / 5–10 days), over-correction, and fabrication/timing details. All dependent-claim conclusions below are therefore conditional and flagged.

3. Motivation evidence that comes from Align's own specification

This is the single most powerful § 103 lever, and it is independent of any reference:

• The '880 Description of the Background Art admits that conventional treatment already required "installing a different archwire having different force-inducing properties" at 3-to-6-week intervals. That is an admission that staged, incremental, successive force application was the standard of care.
• The same section admits the objectives: economical, reduce the time required by the orthodontist, "less visible, less uncomfortable, less prone to infection, and more compatible with daily dental hygiene."
• The specification then admits the enabling technologies individually: Kesling positioners; Warunek's silicone positioners for "comprehensive orthodontic realignment"; commercially available clear plastic retainers (Raintree Essix; Tru-Tain); positioner manufacture (the seven Breads/Abbate patents); digital tooth imaging (Lemchen '405); laser scanning to 3-D models (Wu '338,198; Kuroda; '605,459); digital manipulation of tooth contours ('607,305 / '587,912); Ormco's digital appliance-design patents; computerized jaw imaging ('342,202 / '340,309); 0.03-in. Tru-Tain thermal-forming dental material; and BIOSTAR pressure-molding equipment.
• The specification itself frames the stage count as routine optimization: "Most often, the methods and systems will reposition teeth in from ten to twenty-five successive steps, although complex cases … may take forty or more steps."

Under KSR, an applicant's own characterization of the problem and of the known solutions is strong evidence of the POSITA's knowledge and of a design incentive.

4. Ground I — Snow '482 + Hultgren '334 + Kesling (the IPR2016-00270 template)

This is the strongest ground because a PTAB panel already ran it to a Final Written Decision and the Federal Circuit affirmed.

Reference roles

The express motivation, as found by the tribunal: ClearCorrect's expert testified that "the combination of Snow, Hultgren, and Kesling represent the natural progression of using digital technology to assist in the fabrication of dental appliances," and that "given the detailed disclosures of Snow, Hultgren and Kesling and the predictability of this technology, it would have been understood that this combination would be reasonably likely to succeed." The Board credited this and found claims 1, 2, 9 and 10 of the sibling U.S. 6,699,037 unpatentable. The Board also rejected Align's attempted "bodily incorporation" and soft-tissue arguments. Source (FWD excerpt): http://knobbemedical.com/wp-content/uploads/2017/03/Decision-4.pdf ; CAFC affirmance: http://cafc.uscourts.gov/sites/default/files/opinions-orders/17-2106.Opinion.8-22-2018.pdf

KSR rationales engaged: (A) known elements by known methods → predictable result; (D) applying digital scanning/rapid-prototyping to the Kesling positioner, a known device ready for improvement; plus market forces (labor cost, chair time).

Residual gap to argue: Snow does not itself teach fabricating a series of appliances; the chain is Snow (series of data sets) → Hultgren (series of positive models from those data sets) → Kesling (appliance as a negative of a positive model), which the Board accepted as "based on" the data sets. A patent owner will attack each link; the ITC Staff's "predetermined = fixed before fabrication" construction, however, is fully satisfied because Snow's interpolation series is computed in the computer before any physical model exists.

5. Ground II — Nahoum (1964) + van der Zel '928 + Snow '482 (the Examiner-endorsed combination)

This ground is important because it was actually run by the Examiner in the family's own prosecution, not merely by a competitor.

• Nahoum, "The vacuum formed dental contour appliance," N.Y. State Dent. J. 30(9):385-390 (Nov. 1964) — § 102(b). Per the '840 reexamination record, Nahoum "discloses molding thin polymer shell appliances over a series of positive models of repositioned teeth." That is a direct teaching of the "series" (L1) and of the negative-of-positive-model fabrication step (M3). Source: https://www.docketalarm.com/cases/PTAB/IPR2016-00270/Inter_Partes_Review_of_U.S._Pat._6699037/docs/08-24-2016-Patent_Owner/Exhibit-2047-46-Exhibit_2047_Part_3_of_3.pdf
• van der Zel, US 4,937,928, "Method of Making a Dental Crown … by Means of a CAD-CAM System," filed Oct. 5, 1988, issued July 3, 1990 — § 102(b). Discloses automated CAD/CAM fabrication of positive tooth models (M3).
• Snow '482 supplies the series of successive digital data sets (L3).

The Examiner's own finding: "The Examiner correctly determined that the combination of Nahoum … and van der Zel … made such claims obvious." That finding was made against sibling U.S. 6,629,840, which shares the '880's title and specification.

KSR rationale: (B) simple substitution — replace Kesling's manual plaster/wax set-up with the known automated CAD/CAM model-making of van der Zel; (A) predictable combination; motivation from the admitted objective of reducing orthodontist time and labor.

6. Ground III — the "predetermined series" (L2) limitation: Kesling's own 1946 series + Warunek 1989 + the admitted archwire cadence

Grounds I and II are strongest on L1 and L3. L2 ("predetermined" = fixed at the outset) is the limitation the ITC construed most narrowly, so it needs its own motivation showing:

1. Kesling himself proposed the series in 1946. The 1989 JCO article by Warunek, Strychalski and Cunat states: "Kesling introduced the tooth positioner for artistic finishing in 1945, and proposed a series of positioners for graduated movement toward a corrected occlusion in 1946." If accepted, this is close to dispositive of the concept of a predetermined multi-appliance sequence. (Source: JCO volume 23, no. 10, Oct. 1989 — https://www.jco-online.com/search?q=orthodontics&Page=175. Confidence: moderate — snippet-level, not the full article text.)
2. Warunek et al. (1989) — "silicone positioners for the comprehensive orthodontic realignment of a patient's teeth" — shows the art had already moved past the "finishing-only" limitation. See also Warunek et al., AJODO 95(5):388-400 (1989): conventional positioners were "primarily indicated as finishing devices," but newer materials had "claims of a greater range of tooth movement" — which defeats the teaching-away argument rather than supporting it.
3. Cureton (1996), "Correcting malaligned mandibular incisors with removable retainers," and Kleemann & Janssen (1996), "The speed positioner," both J. Clin. Orthod. — § 102(b), showing active tooth movement (not merely retention) with removable polymeric devices.
4. The admitted archwire cadence (the '880 Background, discussed in § 3) establishes that sequential, staged force changes over months were ordinary orthodontic practice.
5. The digital pre-computation step. Once Snow '482 is in the combination, pre-computing the entire sequence is the natural output of the machine — Snow claim 6 recites that the intermediate states are automatically generated.

Motivation: eliminating the repeated office visits and lab cycles the specification itself identifies as the problem; the "single package, sequenced at the outset" concept is the direct consequence of the admitted objective.

KSR: obvious to try and predictable variation of a result-effective parameter (how many stages, how large each stage).

7. Ground IV — corroborating "successive digital data set" references

These were asserted by the requester in the family reexamination and are useful as § 103 corroboration/secondary teaching, though two are weak on dates:

Use: These defeat any argument that the scheduling of a tooth from initial to final position in discrete digital stages was novel, and they supply the KSR rationale (C) — applying a known digital-simulation technique to a known orthodontic problem in the same way it had been applied elsewhere.

8. Dependent-claim obviousness (conditional — see the flag in § 2)

9. Motivation synthesis

A single, coherent motivation story covers every ground, and each strand is independently supported:

1. Labor and cost. Kesling's series was manual and labor-intensive; Snow, Hultgren and van der Zel all frame their systems around eliminating physical casts and manual set-ups. The IPR2016-00270 Board credited exactly this: "[to] replace Kesling's labor-intensive process with a computerized process, resulting in labor cost savings and resulting in modeling of more precise teeth movement."
2. Precision. The '880 specification's own objective ("less uncomfortable," precise repositioning) aligns with the digital-modeling rationale.
3. Patient convenience / reduced chair time. The admitted complaint about repeated 3–6 week visits is the design incentive to fabricate the whole sequence at once.
4. Maturity and predictability. Dental CAD/CAM was reviewed as state-of-the-art in 1987–88 (Rekow; Duret; van der Zel), and Hultgren had already applied stereolithography to dental casts by 1997. Each step was known; KSR requires only a "reasonable expectation of success" the Board found "detailed" and "predictable."

Thus: L1 (series of polymeric shell aligners) ← Kesling 1946/1949; Nahoum 1964; Warunek 1989. L3 (series of successive digital data sets) ← Snow '482; Alcañiz/Biggerstaff/Hikage. L2 (predetermined before fabrication) ← Snow's automatically generated interpolation series + the admitted design incentive to avoid repeat visits. M3 (fabricate from the data sets) ← Hultgren '334; van der Zel '928; Hull '330.

10. Rebuttal: teaching away and secondary considerations

Teaching away — the best available argument, and why it likely fails.

• Argument: Kesling's positioner was a finishing device; positioner elastomers were "relatively inelastic and … primarily indicated as finishing devices" (Warunek 1989, AJODO). A POSITA would not have used a series of them for comprehensive movement.
• Counter-evidence (all from the same 1989 paper and its context): (i) Kesling himself "proposed a series of positioners for graduated movement"; (ii) Warunek's 1989 work is expressly about newer materials "with claims of a greater range of tooth movement"; (iii) Warunek's JCO paper is on "comprehensive orthodontic realignment." The art pointed toward the series, not away. A teaching-away argument requires the reference to "criticize, discredit, or otherwise discourage" the combination — that is not present here.

Secondary considerations.

• Align's best evidence is commercial success (Invisalign), long-felt need, and copying by OrthoClear/ClearCorrect.
• Nexus problem: the commercial success is at least as attributable to invisibility, removability, hygiene and the treatment-delivery model — all recited in the specification's own background as pre-existing objectives — as to the "predetermined series based on successive digital data sets" limitation.
• Precedent: in IPR2016-00270 the Board gave Align's secondary-considerations evidence "little weight." Expect the same treatment.
• Long-felt need is undercut by the applicant's own admissions: the problem was long-recognized and every constituent solution was known and cited in the patent itself.

11. Counter-evidence for the patent owner (and practical caveats)

I must be balanced; the § 103 case above is stronger on paper than anything that has actually succeeded against this patent.

1. All 21 claims survived ex parte reexamination. Per the PTAB section, the ClearCorrect-requested reexam (Control No. 90/013,491) issued certificates in February 2017 confirming all challenged claims without amendment. If accurate (flagged: not primary-source verified), the Office has already considered Snow/Hultgren/Nahoum-class art against these claims and declined to cancel. Expect a § 325(d) argument — this art is "the same or substantially the same" as what the Office already weighed.
2. No AIA trial was ever instituted on the '880 patent (PTAB section). The ClearCorrect IPR campaign targeted U.S. 6,699,037 instead. A defendant cannot claim any Board has ever held an '880 claim unpatentable.
3. The closest merits loss is on a sibling with different claims. The '037 FWD is persuasive authority and a roadmap, not estoppel, and it does not itself cancel any '880 claim.
4. Expiration. The patent expired 2017-10-08. An IPR is still available but is leverage-only; if any live dispute exists it is a § 286-limited past-damages case.
5. New live 2026 item not in the earlier sections (flagged): a February 3, 2026 Patent Owner exhibit was filed in IPR2025-00816, ClearCorrect Operating LLC v. Align Technology Inc., reproducing EX1007 from IPR2016-00270 — i.e., ClearCorrect is re-running the Snow/Hultgren/Kesling theory in a new 2025–2026 proceeding. https://www.docketalarm.com/cases/PTAB/IPR2025-00816/ClearCorrect_Operating_LLC_v._Align_Technology_Inc/02-03-2026-Patent_Owner/Exhibit-2017-EX2017___Copy_of_EX1007_in_IPR2016_00270/ — I could not confirm which patent IPR2025-00816 challenges; it should not be assumed to be the '880 patent. Treat it as intelligence on how the Board is currently treating this art, not as '880 precedent.

12. Bottom line

A legally defensible § 103 invalidity case against claim 1 and claim 12 of US 6,722,880 exists, built on three independent, self-reinforcing grounds:

1. Snow '482 + Hultgren '334 + Kesling '432 — the exact combination a PTAB panel held rendered comparable claims of the sibling '037 patent unpatentable, affirmed by the Federal Circuit (No. 2017-2106, Aug. 22, 2018). Single strongest ground.
2. Nahoum (1964) + van der Zel '928 + Snow '482 — the combination the Examiner himself found obvious in the family's own prosecution of the '840 patent.
3. Kesling's own 1946 series-of-positioners proposal + Warunek (1989) + the '880 specification's admitted archwire-change cadence — supplies the motivation for the "predetermined series" limitation (L2), which the ITC construed narrowly and which is therefore the crux.

The motivation is not speculative: it is (i) recited in the Board's own FWD, (ii) recited in the applicant's own Background as the object of the exercise, and (iii) reinforced by the admitted state of dental CAD/CAM in 1987–1997.

But the honest verdict is "invalidity is arguable, not established." Two Office proceedings have already declined to cancel these claims, no Board has ever ruled on them, and the § 325(d) overhang is significant because the reexam art substantially overlaps the grounds above. The genuinely new material here — Snow's automatic interpolation series, Kesling's 1946 series proposal, Nahoum's series of positive models, and van der Zel/Hultgren as the CAD/CAM fabrication legs — would have to be packaged as a materially new theory, and even then the patent's 2017 expiration makes the filing economically marginal.

Items still open and flagged rather than resolved: the full verbatim text of claims 1–21; the actual reexamination certificate (Control 90/013,491) and exactly which claims it confirmed; the Board's articulated level of ordinary skill in IPR2016-00270; the precise publication date of EP 0 362 617 B1; and the patent actually challenged in IPR2025-00816.