US 6449562

I'll search for authoritative information on this patent number before summarizing.

Let me search specifically for the claims and any litigation involving this patent.

Let me try to retrieve the actual claim text for this patent.

Search results — what I found and did not find

Important caveat up front: I ran web searches against publicly indexed patent records and litigation documents. I did not get direct access to the USPTO PatentCenter/Assignment database or to a live CAFC docket feed. Accordingly:

• I found no entry on any 2026 CAFC docket involving US 6,449,562. The only 2026 Federal Circuit materials my searches surfaced (e.g., Fed. Cir. No. 2026‑2012, Contour IP Holding LLC v. GoPro, Inc.) concern unrelated patents. This is consistent with the patent having expired, which makes active appellate litigation unlikely.
• I found no result for any other patent numbered 6449562 in the U.S. system. One search hit was JP 6449562 B2 (a Toyota body-structure patent, published 2019‑01‑09) — a Japanese patent number, not a U.S. patent, and unrelated. I flag it only because it is a same-numbered record you may encounter; it should not be conflated with US 6,449,562.
• The Google Patents record supplied in the task is the authoritative source I relied on for bibliographic data. Its text as provided does not include the claim set, and the description text is truncated mid‑sentence ("test-type token of '0' means an OVER/UNDER int…"). For the claim language below I relied on a secondary aggregator (RPX Insight) plus the published divisional application US 2004/0059519 A1; treat the claim wording as reasonably but not perfectly verified.

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US 6,449,562 B1 — Bibliographic summary

Abstract (as printed): A method for the multiplexed diagnostic and genetic analysis of enzymes, DNA fragments, antibodies, and other biomolecules comprises the steps of constructing an appropriately labeled beadset, exposing the beadset to a clinical sample, and analyzing the combined sample/beadset by flow cytometry. Flow cytometric measurements are used to classify, in real-time, beads within an exposed beadset, and textual explanations, based on the accumulated data obtained during real-time analysis, are generated for the user. The technology enables simultaneous, automated detection and interpretation of multiple biomolecules or DNA sequences in real-time while reducing the cost of performing diagnostic and genetic assays.

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Plain-language overview of the claims

The distinguishing feature of the '562 patent is that its independent claims are directed to thedata structure (an "assay database") used to drive the flow‑cytometric analysis — not to the wet-lab assay itself. The chemistry is described in the specification and is largely the subject matter of the sibling US 5,981,180 and the divisional US 2004/0059519. Here, the 13 claims break down as four independent claims (1, 3, 6, 7) with dependent claims 2, 4, 5, 8–13 narrowing them.

Claim 1 — "computer readable medium storing an assay database" (independent).
Covers a non-transitory-style computer-readable medium holding a database for processing a pooled population of particle subsets during flow analysis. The database must contain two things:

• (a) a discriminant function table that encodes a decision tree for classifying each particle, in real time, to its subset, based at least in part on a classification parameter that includes at least one fluorescence emission intensity; and
• (b) an assay definition table likewise encoding a decision tree, which defines the assay by identifying each subset and storing at least one baseline assay measurement value used to interpret a result.

Claim 3 — "machine readable assay database, stored in a storage device" (independent).
Covers the database itself as a stored artifact for processing flow-cytometric measurement data, reciting four cooperating tables:

• (a) an assay definition table encoding (1) subset token identifiers, (2) a baseline measurement parameter value for each token, and (3) an interpretation test-type token for each token;
• (b) a discriminant function table encoding a real-time classification decision tree keyed to classification parameters carried in the flow-cytometric data;
• (c) an interpretation table encoding textual assay-outcome descriptions; and
• (d) a results table capable of encoding statistical accumulation of real-time measurement data.

Claim 6 — "computer readable medium storing an assay database" (independent).
A narrower variant of claim 1, differing mainly in reciting classification of each particle "in one step" by its subset, again requiring the fluorescence-emission-intensity classification parameter plus the assay definition table with a baseline measurement value.

Claim 7 — "computer readable medium storing an assay database" (independent).
The broadest of the four in one respect: it drops the express "fluorescence emission intensity" and "real time" requirements, requiring only (a) a discriminant function table encoding a decision tree for classifying each particle by subset based on at least one classification parameter, and (b) an assay definition table encoding a decision tree for defining an assay based at least in part on at least one baseline measurement parameter value.

Dependent claims 2, 4, 5, 8–13 add limitations such as further table fields, additional classification parameters (e.g., light scatter), additional measurement parameters, and data-structure/format specifics. I do not have verified verbatim text for every dependent claim, so I am not characterizing them individually beyond this.

Practical reading

In substance the '562 claims cover the software/informatics side of multiplexed bead-based flow cytometry: the lookup tables and discriminant-function decision trees that let an instrument (i) sort each bead into its coded subset in real time and (ii) convert the reporter fluorescence into a reported, textually interpreted assay result. The specification explains the underlying scheme in detail — each bead subset is homogeneous in classification parameters C₁ (forward light scatter), C₂ (side light scatter), C₃ (red fluorescence) and C₄ (orange fluorescence) but differs between subsets, while the measurement signal F_m (e.g., green fluorescence) reports the analyte reaction; discriminant functions are generated from baseline data collected on unexposed subsets and may conveniently be linear (Fisher linear discriminant, chosen equidistant between subset centroids).

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Litigation / PTAB posture (what I could and could not confirm)

• No 2026 CAFC appeal involving US 6,449,562 was found. Given the anticipated expiration on 2016‑10‑10, the patent is a poor candidate for current appellate activity.
• The number appears in PTAB/petition paper work-product only as a cited reference in other patents' prosecution (e.g., it is cited in later Luminex and third-party filings), not as the challenged patent in an instituted proceeding that I could confirm.
• Luminex-related litigation my searches surfaced involves different patents: Irori Technologies v. Luminex (S.D. Cal. 3:13‑cv‑02647, asserting US 6,372,428 / 6,416,714 / 6,352,854); Enzo Life Sciences v. Abbott et al. (D. Del. 1:12‑cv‑00274, settled with Luminex in 2015); Research Foundation of SUNY v. Luminex (N.D.N.Y. 1:2007‑cv‑01260); and Signify North America v. Menard (W.D. Wis. 3:22‑cv‑00706, with Luminex International as a third‑party defendant). None of these identify US 6,449,562 as an asserted patent in the records I retrieved.

If you need a definitive litigation check, the authoritative step is a USPTO PatentCenter / Assignment search plus a PACER/CAFC docket query on the exact string "6,449,562" (and "6449562"), which I could not execute directly here.

I'll research litigation involving US Patent 6449562 across patent litigation databases.

Let me search more targeted litigation databases.

Let me search patent-specific litigation databases directly.

Findings on Litigation Involving U.S. Patent No. 6,449,562

Bottom line: I could not verify any litigation — in U.S. district courts, the Court of Appeals for the Federal Circuit, or the PTAB — in which U.S. Patent No. 6,449,562 ("Multiplexed analysis of clinical specimens apparatus and method," Luminex Corp., filed/priority 1996‑10‑10, granted 2002‑09‑10, expired 2016‑10‑10) was asserted as a patent‑in‑suit. Treat this as a negative finding with the caveats below, not as an affirmative statement that no such case ever existed.

What I searched and what I found

Identifiers that are NOT this patent (do not conflate)

Per your instruction to interpret IDs literally, these surfaced but are unrelated:

• JP 6449562 B2 — a Toyota Motor Corporation Japanese patent issued 2019‑01‑09 ("車両用骨骨構造," vehicle frame structure). Coincidental number, different jurisdiction, different technology.
• Ato n.º 6449562 — a Brazilian municipal procurement act (Município de Vargem Bonita, 2024). Unrelated.
• EP/other citations of "US 6449562 B1" in EP specifications (e.g., EP2844748A1, EP2982963A1, EP3455356B1) — these are merely the '562 patent being cited as prior art in European applications.

Important caveats on completeness

1. Search coverage was partial. My lookups hit PTAB filings, patent documents, and general web results, but I did not obtain an authoritative case list from Uni­fied Patents' caselist, Docket Alarm/Navigator, or a PACER/RECAP docket query filtered to this patent. A direct query of those paywalled/structured databases is required for a definitive negative.
2. Timing. The patent expired 2016‑10‑10, so any assertion would have occurred on or before that date (damages window). Older cases (late 1990s–2010s) may not surface in the sources I reached.
3. Luminex's known patent activity generally (e.g., Luminex's later assertion of different patents such as U.S. 10,299,336 in Signify v. Menard, W.D. Wis. 3:22‑cv‑00706) does not involve the '562 patent and should not be attributed to it.

Recommendation to confirm

To close this out with authority, run:

• Unified Patents – https://portal.unifiedpatents.com/litigation/caselist (search "6,449,562")
• Docket Alarm / Docket Navigator – party "Luminex Corporation" + patent filter 6,449,562
• CourtListener/RECAP – https://www.courtlistener.com (query "6,449,562")
• USPTO Patent Litigation Dataset (OCE) API – https://data.uspto.gov/bulkdata/datasets/ptlitig (filter patent_number = 6449562)

If those return nothing, the correct conclusion is no known litigation involving U.S. 6,449,562. I have not fabricated any case name, court, or docket number, because I could not substantiate one.

I'll verify the structured "no proceedings" default against live sources before writing the report.

The structured default holds so far — '562 appears only as cited art in unrelated petitions. Let me probe a few more angles, including any pre-AIA challenges and the assignee timeline.

Let me run one more verification round on the specific petitioner/patent-owner combinations and any pre-AIA reexamination, then write the report.

Proceedings overview

Total AIA trial proceedings on US 6,449,562: 0. Active: 0. Claims invalidated: 0. Claims sustained: 0. Settled: 0. Institution denied: 0. The USPTO Open Data Portal structured block supplied with this prompt returns no AIA trial proceedings for this patent as of the most recent ingest, and my independent web searches did not surface any — no IPR, no PGR, no CBM, and no pre‑AIA inter partes or ex parte reexamination that I could confirm.

Defensive posture: neither of the two framings in the assignment brief applies. The patent has not "survived two IPRs and is hardened," and no claims have been canceled. The correct characterization is zero PTAB track record, zero PTAB estoppel, and an expired term — which happens to be a very strong defensive position, but for reasons unrelated to the Board. Every claim (1–13) is UNTESTED at the PTAB, and, as explained in the Strategic summary, no competitor currently has any damages exposure to worry about regardless of what those claims say.

I found no contradiction with the previously generated "PTAB proceedings on file" section; my searches corroborate the "no PTAB activity" default.

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No proceedings to report — but four near-misses you will hit if you search this number

Because there is no FWD, no institution decision, no panel, and no appeal to report, the useful work here is telling a defendant how the number 6449562 shows up in PTAB-adjacent search results and why none of it is a proceeding against this patent.

1. "6449562" inside PTAB petitions = cited prior art, not a challenged patent

The number appears in PTAB petition papers only as a prior-art citation in petitions challenging other patents. Example indexed from the PTAB public petitions database: an unrelated petition's exhibit (https://ptacts.uspto.gov/ptacts/public-informations/petitions/1556784/download-documents, artifactId 6LTJdDKPoUGi00y36M3ctyDK-r_RDHJ-kb_I7ucIwTwavEbaQ_xov4g) lists OR US-6449562- among cited references, and a companion paper lists 6449562 in a table of patents with a column headed ASSIGNEE dated 12-02-2020. That date is an assignment/reel-frame record, not a PTAB trial event, and it is not a proceeding number. Do not read a "Case No." out of it.

2. A different "562 patent" at the Federal Circuit — the single most dangerous conflation

A CAFC opinion (Fed. Cir. No. 05‑1351, Philips/CMT, https://cases.justia.com/federal/appellate-courts/cafc/05-1351/05-1351-2011-03-27.pdf) contains a section literally captioned "2. The '562 patent" discussing "an entry initiate key," "entry initiate signal," and a "learn/scan routine." That is an unrelated patent in a consumer-remote-control case. Anyone running a keyword search for "562 patent" plus "Federal Circuit" will land here. It has nothing to do with US 6,449,562. Likewise, the ITC opinion at https://www.usitc.gov/intellectual_property/documents/pub4366.pdf discusses a "'562 patent" about "print quality" in the RPost matter — again a different patent.

3. JP 6449562 B2

Toyota Motor Corporation, "車両用骨格構造" (vehicle frame structure), granted 2019‑01‑09 (https://patents.google.com/patent/JP6449562B2/en). Same digits, different jurisdiction, different technology. Noted for completeness only; the prior sections already flagged this.

4. European specifications citing "US 6449562 B1"

E.g., EP3954771A1 and EP2844748B1 reference it purely as prior art. Not a proceeding.

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Strategic summary

Claim-by-claim status. All 13 claims are UNTESTED — none canceled, none sustained by any tribunal. The claims relevant to today's assertion posture are the four independent claims identified in the earlier claim analysis: claim 1 (computer-readable medium storing an assay database with a discriminant-function decision tree), claim 3 (machine-readable assay database in a storage device with four cooperating tables), claim 6 (narrower variant of claim 1 reciting "in one step"), and claim 7 (broadest — drops the express fluorescence-emission-intensity and real-time limitations). Dependent claims 2, 4, 5, and 8–13 are likewise untested.

Estoppel landscape. § 315(e)(2) estoppel is inapplicable. Estoppel attaches only to a petitioner that obtains an instituted IPR (or PGR/CBM) and reaches a final written decision; here there is no petitioner, no institution, and no FWD. Concretely, a defendant today faces no statutory constraint whatsoever on invalidity grounds: the full § 102/§ 103 universe, § 112 defenses, and — critically — § 101 subject-matter defenses, which are categorically unavailable in IPR. That last point matters because the '562 claims are drawn to a data structure / database for driving an instrument, which is the classic fact pattern for an Alice challenge under § 101 — an attack that can only be brought in district court or the ITC, and that no IPR petitioner could ever have raised. The absence of IPRs therefore costs the patent owner nothing in terms of art-based freedom and gains a defendant nothing by way of estoppel — it is simply a blank slate.

Pattern signals. None available. There is no repeat petitioner, no defensive aggregator (no Unified Patents or similar filing against this patent), no patent-owner appeal activity, and no joinder history. The absence is itself the signal: a patent with 1996 priority, issued 2002‑09‑10, and expired 2016‑10‑10 was a plausible IPR target across the entire 2012–2016 window (any member of the public could have filed; § 315(b)'s one-year bar is triggered only by service of a complaint, and no assertion was identified in the earlier litigation sections), yet nobody did. For a defendant, the practical significance of that blank slate is dwarfed by the term itself.

The controlling fact is expiration, not the PTAB. The last day on which infringement of US 6,449,562 could possibly have occurred is 2016‑10‑10. Under 35 U.S.C. § 286, damages are recoverable only for infringement occurring within six years before the filing of a complaint. As of today (2026‑09‑29), a newly filed complaint reaches back only to 2020‑09‑29 — a date entirely after the patent expired. There is accordingly no recoverable damages window for any suit filed now, and no possibility of injunctive relief against an expired patent. A demand letter citing this patent and threatening suit is, in substance, unenforceable. (Caveat: this assumes no pre-expiration action is pending, consistent with the earlier litigation findings; if a suit was filed before 2022‑10‑10 and remains live, § 286 would not bar the pre-expiration window at issue in that case. My searches did not identify such a case, and the earlier litigation section reached the same conclusion.)

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Recommended next steps

1. If you received a demand letter citing US 6,449,562: do not run an IPR. There is nothing to institute against — the patent expired 2016‑10‑10 and, given § 286, no damages can be recovered on a complaint filed after 2022‑10‑10. The proportionate response is a short letter explaining expiration and § 286, not a petition. Note that IPR of an expired patent is legally permissible where a past-damages window remains, but that rationale evaporates here.
2. Confirm the zero count authoritatively before relying on it, since I could not directly query the structured source or PTAB E2E. Run: the PTAB E2E / PTAB Public Search (https://ptab.uspto.gov) filtered on patent number 6449562; the USPTO ODP / PTAB API filtered to patent_number = 6449562; Unified Patents caselist (https://portal.unifiedpatents.com/litigation/caselist); and CourtListener/RECAP (https://www.courtlistener.com, query "6,449,562" — note the comma, to suppress the CMT/RPost "562 patent" noise).
3. Check the sibling and divisional family separately, not by number. If the commercial dispute is really about Luminex-family subject matter, the asserted patents will likely be other members — US 5,981,180, US 5,736,330, US 6,632,526, US 6,929,859, or the divisional US 2004/0059519 A1 — each of which has its own proceedings history that I did not investigate here. Do not assume the '562 result carries over.
4. Preserve the § 101 / § 112 defenses, not the § 102/§ 103 ones. With no IPR estoppel in play, nothing is foreclosed — but nothing is foreclosed for the patent owner either. The strongest available defense to a database-claims patent of this vintage is eligibility, not anticipation, and it must be raised in court.
5. Do not cite any decision, panel, or docket number for this patent. There are none. Any "FWD" or "IPR20xx‑xxxxx" you encounter attached to the number 6449562 is either cited-art context from an unrelated petition or a conflation with a different '562 patent.

Caveats on completeness (stated plainly): I did not obtain direct access to PTAB E2E, the ODP PTAB dataset, or Docket Navigator; three planned verification searches (for Luminex-family IPRs, for any "unpatentable/canceled" claims language tied to this number, and for a trial number naming the patent) returned a step-limit error before executing. My negative finding rests on the canonical structured block plus six executed searches, and I have not fabricated any proceeding identifier, panel, or disposition to fill the template.

I'll research the assignment record and ownership chain for US 6,449,562.

Let me dig deeper into the specific assignment records and Luminex corporate history.

Ownership-chain analysis — US 6,449,562 B1

Sourcing caveat stated up front (per operating rules). I could not execute a live query against USPTO Assignment Center / assignment.uspto.gov from this session, and the authoritative Google Patents record supplied in the task does not reproduce reel/frame numbers, execution dates, or the correspondent of record. Everything below is therefore built from (a) the Google Patents "legal events" block in the authoritative text, (b) the printed front page of the patent, (c) the PCT front page (WO 97/14028 A3), and (d) DiaSorin/Luminex corporate filings. I have not fabricated a reel/frame number, an execution date, or a correspondent name. Where a field is missing I say so and tell you exactly how to close it out.

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Inventors

Employer determination. The patent record alone does not recite an employment relationship, but the PCT application PCT/US96/16198 — from which this patent descends — named LUMINEX CORPORATION [US/US], 12212 Technology Boulevard #K, Austin, TX 78727‑6115 as applicant for all designated states except the US, with the three inventors named only as inventor‑applicants for the US. That is the standard signature of company‑held rights: the inventors had already obligated their rights to Luminex at the Oct. 10, 1996 priority/filing date. Luminex's address on the PCT front page (12212 Technology Blvd.) is the same address later given as Luminex's corporate HQ in the DiaSorin merger documents ("12212 Technology Blvd., Suite 130, Austin, Texas").

Patterns worth noting (and one that is not present):

• No inventor exodus. The "all inventors depart within 12 months" fire‑sale precursor is absent. All three inventors continued to appear as Luminex inventors on later filings across the same technology family: Chandler and/or Fulton on US 6,046,807 (2000), 6,139,800 (2000), 6,268,222 (2001), 6,366,354 (2002), 6,411,904 (2002), 6,514,295 (2003), 6,524,793 (2003), 6,528,165 (2003), 6,599,331 (2003), 6,632,526 (2003), 6,649,414 (2003) — all Luminex‑assigned. Mark B. Chandler is also named on Luminex's WO 01/63284. Inventorship continuity runs to at least 2003.
• Same‑surname co‑inventors. Van S. Chandler and Mark B. Chandler both appear; the patent does not state a relationship, and I have no independent evidence of one. Flagging rather than inferring.
• Address discrepancy to be aware of. Van S. Chandler is listed as Austin on the '562 patent front page but as Dallas (2808 McKinney Avenue #410) on the WO 97/14028 front page and on sibling US 5,981,180. This is a residency/venue detail, not an ownership one, but it is a genuine internal inconsistency across the family.
• Fulton name variant. "Jerrold R." (patent, USPTO assignment) vs. "R. Jerrold" (WO, US 5,981,180). Same person; relevant if you run automated name matching across the family.

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Original assignee

Luminex Corporation, Austin, Texas — named on the issued patent at (73), and shown as "Original Assignee" and "Current Assignee" on the Google Patents record.

• Shipped a product embodying the claims: yes. Luminex was not a paper assignee. Its FlowMetrix / xMAP flow‑cytometric microsphere platform is the commercial embodiment of this disclosure, and the inventors themselves published on it ("Fulton, R.J., R.L. McDade, P.L. Smith, L.J. Kienker, and J.R. Kettman Jr. 1997. Advanced multiplexed analysis with the FlowMetrix™ system. Clinical Chemistry 43: 1749‑1756"; also Kettman et al. 1998, "Classification and properties of 64 multiplexed microsphere sets"). The '562 claims are directed to the assay data structure (discriminant‑function table + assay definition table) that drives that instrument, so the practicing product is the instrument/software.
• Primary line of business: multiplexed bioassay instrumentation and consumables (Life Science and, later, molecular diagnostics / IVD).
• Current status: Operating, then acquired. Founded 1995 in Austin; IPO on NASDAQ (LMNX) April 7, 2000; acquired by DiaSorin S.p.A. for $37.00/share, ≈$1.8B equity value. Merger agreement signed April 11, 2021; Luminex shareholder approval June 21, 2021; CFIUS clearance July 8, 2021; closing July 14, 2021, effected by merger of DiaSorin subsidiary "Diagonal Subsidiary Inc." into Luminex, with Luminex as the surviving entity and DiaSorin Inc. holding 100%. Delisted from NASDAQ. Not bankrupt, not dissolved, not a fire‑sale.

Timing note that matters for the assignment analysis: the '562 patent's anticipated expiration was 2016‑10‑10 — five years before the DiaSorin acquisition. The patent was already expired when Luminex was sold, so it was not a live asset transferred in the 2021 merger and there is no reason a post‑2021 assignment would be recorded against it.

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Assignment timeline

The Assignment Center record for this patent contains exactly one recorded conveyance of title. That is the finding, and it is a significant one.

• Execution date: not stated in the record I retrieved / recorded 2001‑05‑03 — Reel/frame NOT RETRIEVED (see caveat below)
  • Conveyance: Assignment of Assignors' Interest (USPTO free‑format text as surfaced by Google Patents: "ASSIGNMENT OF ASSIGNORS' INTEREST (SEE DOCUMENT FOR DETAILS)")
  • Assignor: FULTON, JERROLD R.; CHANDLER, MARK B.; CHANDLER, VAN S.
  • Assignee: LUMINEX CORPORATION (Texas)
  • Correspondent: not retrieved. I did not obtain the recording correspondent from the Assignment Center record, and I decline to guess. Note for verification: the patent's attorney of record is Gilberto M. Villacorta (per the previously generated bibliographic section); whether he was also the assignment correspondent is unverified and should not be assumed — attorney of record and assignment correspondent are frequently different fields.
  • Context: Founders'/inventors' confirmatory assignment to the operating company — i.e., the original vesting of title in Luminex, not a sale, securitization, or transfer to a third party. The 2001‑05‑03 recording date sits between the §371 national‑stage entry (1998‑08‑18) and the grant (2002‑09‑10), and five months before the divisional 09/971,647 was filed on 2001‑10‑09; a late‑recorded batch confirmatory assignment covering the family around the time of the divisional filing and issue is the consistent reading, but the "batch" aspect is my inference, not a recorded fact.

No other conveyance appears in the record. Specifically, the Google Patents legal‑events block for this patent contains only: the 1996‑10‑10 filing/priority entries; the 2001‑05‑03 assignment to Luminex; the 2001‑10‑09 divisional priority entry; the 2002‑09‑10 grant; and the 2016‑10‑10 anticipated expiration. There is no security agreement, no merger‑related assignment, no change of name, and no downstream transfer to any third party.

Caveat / required verification step. Google Patents' legal‑events table is a secondary rendering of the Assignment Center. It is possible (though, given the expiry date and the operating‑company owner, not likely) that additional encumbrances — e.g., a security agreement in favor of a lender around Luminex's 2000 IPO or its later credit facilities — were recorded against a related application or against the family as a whole rather than against 09/000,286 individually. Do not treat the single‑entry chain as final until you run the query yourself: https://assignment.uspto.gov/patent/index.html (search "6449562") or https://assignmentcenter.uspto.gov/. Retrieve: reel/frame, execution date, conveyance type, and — most importantly per your brief — the correspondent of record. If the Assignment Center returns the same single entry, the chain is confirmed.

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Timeline diagram

timeline
    title Ownership of US 6449562
    1995 : Luminex Corporation founded in Austin
    1996 : PCT application filed
         : Luminex named applicant for all states
    2000 : Luminex IPO on NASDAQ
    2001 : Inventors assign rights to Luminex
    2002 : Patent US 6449562 issues
    2016 : Patent expires
    2021 : DiaSorin acquires Luminex

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NPE / troll-pattern signals

One terminological trap to avoid. The Google Patents event dated 2001‑05‑03 is labeled "reassignment." That is Google's generic event‑category tag for any post‑filing assignment record; it is not a USPTO conveyance type and does not indicate a re‑assignment from a prior third‑party owner. The underlying free‑format text is the ordinary "ASSIGNMENT OF ASSIGNORS' INTEREST," i.e., first vesting of title in the company.

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Verdict

Insufficient data — in the strict sense defined by your rubric (only the original assignment is on record).

Justification. The entire recorded chain is one conveyance: the inventors' assignment to Luminex Corporation, recorded 2001‑05‑03, followed by the 2002‑09‑10 grant and the 2016‑10‑10 expiration, with no security agreement, merger assignment, or downstream transfer ever recorded. Because that single entry is the whole chain, the "NPE — high confidence" and "NPE — moderate confidence" verdicts are unavailable (zero of the eight signals are present), and "operating‑company assertion" is also unavailable on the evidence, since no suit asserting this patent was found — Luminex shipped the practicing product but I cannot document an assertion of this patent. The affirmative finding that matters for your purpose is a negative: there is no shell‑entity transfer, no known asserter, no cascading transfer, no fire‑sale, and no defensive‑aggregator endpoint — the patent stayed with the operating inventor‑assignee for its whole life and expired in place. Score this as a clean non‑NPE chain, with the residual insufficient data label driven solely by the unverified reel/frame, execution date, and correspondent.

Verify at: https://assignment.uspto.gov/patent/index.html (query "6449562") and https://assignmentcenter.uspto.gov/. Specifically request reel/frame, execution date, conveyance type, and correspondent of record for the 2001‑05‑03 entry.

I'll search for the specific patent and its cited prior art references.

Let me get the actual front-page references cited in US 6,449,562 specifically.

Let me retrieve the actual front-page "References Cited" for US 6,449,562 specifically.

Prior Art for US 6,449,562 — Findings and § 102 Analysis

Sourcing caveat (read first)

I want to be precise about what I could and could not verify, because the request hinges on "each patent citation for 6449562."

• I was not able to retrieve the literal front page ("References Cited" box) of US 6,449,562 itself in this session. The Google Patents text that you supplied as authoritative does not reproduce the front-page reference list, and my searches returned the family-level record rather than the '562 face page. I therefore cannot give you a byte-for-byte transcription of the '562 front page.
• What I could substantiate is the reference list from the same-family/related Luminex "Multiplexed analysis of clinical specimens apparatus and method(s)" record (the Justia record for US 8,148,171, which is in the same family and shares the specification and much of the citation set), plus the non-patent literature quoted in the '562 specification itself.
• Critically, many of those same-family references post-date the '562 priority date (1996-10-10) — e.g., US 6,649,414 (2003), WO 99/37814 (1999), US 6,043,066 (2000). Those are forward citations and are not prior art to the '562. I flag them so you do not mistake them for § 102 art.
• Per your operating rules I have not auto-corrected any number and have not invented any citation. Where I am inferring from the family record rather than reading the '562 face page, I say so explicitly.

Important terminological clarification. "Citations for 6449562" is ambiguous and the two meanings must not be blurred:

1. Backward citations = the references the '562 itself cites (what was "of record" during its prosecution) → these are the prior art relevant to a § 102 analysis. This is what your request needs.
2. Forward citations = later patents that cite the '562 (e.g., the many Illumina/Nugen/Luminex references that appear in my searches). These are not prior art to the '562.

My search results were dominated by category (2). I treat them only as context.

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A. U.S. patent references in the family record most plausibly of record as prior art to the '562

I have grouped these by whether they predate the 1996-10-10 priority date (i.e., can be § 102 art) or postdate it (cannot).

Foreign patent documents in the same family record:

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B. Non-patent literature actually quoted in the '562 specification (the strongest § 102 candidates for the method context)

These are cited in the '562 specification/background and in the family record, and they are the references most likely to have been the substantive prior-art basis:

• Shapiro, "Practical Flow Cytometry," Third Ed., Alan R. Liss, Inc., 1995 — cited expressly by the '562 as background for flow cytometry. Publication predates 1996‑10‑10.
• Melamed et al., "Flow Cytometry and Sorting," Second Ed., Wiley‑Liss, 1990 — cited expressly by the '562. Predates.
• McHugh, T.M., "Flow Microsphere Immunoassay for the Quantitative and Simultaneous Detection of Multiple Soluble Analytes," Methods in Cell Biology, vol. 42, 1994, pp. 575–595 — the classic "multiple analytes in one flow run" reference. Highly relevant.
• Saunders et al., "Amplified Flow-Cytometric Separation-Free Fluorescence Immunoassays," Clin. Chem., vol. 31, no. 12, 1985, pp. 2020–2023.
• Lindmo et al., "Immunometric assay by flow cytometry using mixtures of two particle types of different affinity," J. Immunol. Methods, vol. 126, 1990, pp. 183–189 — mixtures of two distinguishable particle types in one run: directly on point for the "classification of pooled subsets" concept.
• Best et al., "Serological Detection of Helicobacter pylori by a Flow Microsphere Immunofluorescence Assay," J. Clin. Microbiol., vol. 30, no. 9, 1992, pp. 2311–2317.
• Scillian et al., "Early Detection of Antibodies Against rDNA-Produced HIV Proteins With a Flow Cytometric Assay," Blood, vol. 73, no. 7, 1989, pp. 2041–2048.
• McHugh et al., "Development of a microsphere-based fluorescent immunoassay…," J. Immunol. Methods, vol. 116, 1989, pp. 213–219.
• Vlieger et al., "Quantitation of Polymerase Chain Reaction Products by Hybridization-Based Assays…," Anal. Biochem., vol. 205, 1992, pp. 1–7 — PCR-product quantitation on particles.
• Yang et al., "Flow Cytometric Detection of HIV-1 Proviral DNA by PCR…," Cytometry, vol. 21, 1995, pp. 197–202.

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C. § 102 anticipation analysis — mapping art to the '562 claims

Recall (from your prior section, treated as authoritative) that the '562's independent claims 1, 3, 6, 7 are data-structure claims — a "computer readable medium storing an assay database" comprising a discriminant-function table encoding a decision tree for real-time classification plus an assay-definition table (and, in claim 3, interpretation and results tables). This framing matters enormously for anticipation.

Key legal point: A § 102 anticipation requires a single reference disclosing every element of the claim, arranged as in the claim. Because claims 1/3/6/7 recite a specific data structure (tables + decision tree) resident on a computer-readable medium for real-time classification, method-only flow-cytometry references cannot anticipate them.

Bottom line on anticipation

On the record I could verify, no single reference anticipates the '562's independent data-structure claims (1, 3, 6, 7). The reason is structural: the '562's inventive contribution as claimed is the software/assay-database data structure (discriminant-function table implementing a decision tree in real time; assay-definition table carrying baseline measurement values and interpretation test-type tokens; plus, in claim 3, interpretation and results tables). Every item of prior art I could substantiate — McHugh, Lindmo, Saunders, Scillian, Best, McHugh 1989, Vlieger, Yang, Fulwyler, and the reagent/instrument patents — is method, chemistry, or instrument art and does not disclose those tables or a decision-tree data structure for real-time classification. At most, this art is relevant to a § 103 obviousness combination against the assay aspects, and even then only against the dependent claims or the specification's method disclosure, not against the database claims.

The genuinely analogous art (US 5,736,330, US 5,981,180, WO 97/14028) is same-family/applicant-owned and is not prior art "by another" under § 102.

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D. What still needs a definitive check (I did not fabricate this)

To close the gap on the literal face-page list for US 6,449,562 — which is what you asked for and which I could not read directly — the authoritative step is the USPTO PatentCenter / Global Dossier file wrapper for application 09/000,286 (the '562's application number), specifically the PTO-892 "Notice of References Cited" forms and the IDS (PTO-1449) submitted by inventors Van S. Chandler, Jerrold R. Fulton, and Mark B. Chandler. Those forms — not the Google Patents/Derwent family list — will give the exact references "of record," with the examiner's initials and the specific claims to which each was applied:

• USPTO PatentCenter: https://patentcenter.uspto.gov (application 09/000,286)
• USPTO Global Dossier: https://globaldossier.uspto.gov
• The '562 PDF face page (front page "References Cited"): https://patents.google.com/patent/[US6449562B1](/patent/US6449562B1)/en (PDF download) — this will render the exact U.S. patent references, foreign references, and examiner citations in the first two columns.

If the front page turns out to list references I did not surface here, the § 102 mapping in Section C should be re-run against that literal list, because the claim charting depends on whether an examiner-applied reference disclosed a data structure versus only an assay method.

I have not asserted any reference, date, or claim mapping that I could not ground in the searches above. Where the record was silent or truncated, I have said so rather than filling the gap.

I'll start by flagging a discrepancy and then gathering grounding for the prior-art analysis.

Discrepancy flag: Your current task says to "Use the results from the Prior Art section of this page," but the previously generated sections supplied to me are the Patent summary and the Litigation summary — there is no "Prior Art" section among them, and the authoritative Google Patents text you provided is truncated (it ends mid-sentence at "test-type token of '0' means an OVER/UNDER int") and does not include the "References Cited" or "Cited By" lists. So I do not have the patent's own prior-art table. Let me search for it rather than assume it.

Good — I now have the patent's cited-reference trail. Let me pull the actual "References Cited" list and check for any validity challenges.

Let me try to pull the actual "References Cited" list from the patent PDF and check the sibling patent's art, plus look for decision-tree/classification prior art.

Obviousness Analysis — U.S. Patent No. 6,449,562 B1

Under 35 U.S.C. § 103 (pre-AIA, 1996 priority)

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0. Threshold caveats — please read before relying on anything below

I must flag two discrepancies up front, because your current instruction depends on material that was not supplied.

1. There is no "Prior Art section of this page" in the materials given to me. The previously generated sections are (i) the Patent summary and (ii) the Litigation summary. Neither contains a prior-art table. I therefore could not "use the results from the Prior Art section." What I have done instead is reconstruct the art from the patent's own cited-reference trail (the Google Patents record and the sibling/related Luminex patent PDFs), which I retrieved by search. Any reference below that is not attributable to those retrieved sources is explicitly labeled as such.

2. The authoritative Google Patents text you supplied is truncated — it ends mid-sentence at "test-type token of '0' means an OVER/UNDER int" — and it does not contain the "References Cited" or "Cited By" lists. The claim characterizations in the prior summary section were drawn from a secondary aggregator and the divisional publication US 2004/0059519 A1. Verbatim dependent-claim text (claims 2, 4, 5, 8–13) is unverified. My mapping below is therefore reliable at the level of the four independent claims and indicative only for the dependents.

3. Legal frame. The '562 patent's § 371 national-stage filing was 1998-08-18 but it claims benefit of PCT/US1996/016198, filed 1996-10-10, which designated the United States. Pre-AIA § 103 therefore applies, with prior art requiring a date before 1996-10-10 (§ 102(a)/(e)) or, for § 102(b) art, before 1995-10-10. This matters enormously, because several references a careless searcher would reach for are not prior art — see § 5 below.

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1. The legal test to be applied

Graham v. John Deere Co., 383 U.S. 1 (1966), as refined by KSR Int'l Co. v. Teleflex Inc., 550 U.S. 398 (2007):

1. Scope and content of the prior art;
2. Differences between the prior art and the claims at issue;
3. Level of ordinary skill in the pertinent art;
4. Obviousness vel non, with the KSR command that a "predictable variation," a "design incentive," or "market forces" — and not merely an express teaching — can supply the motivation to combine.

Level of ordinary skill (proposed): a person with an M.S./Ph.D. in immunology, clinical chemistry, or analytical chemistry, plus 2–3 years' hands-on flow-cytometry assay development experience, or a computer scientist/software engineer with equivalent instrumentation experience working in partnership with such a scientist. Critically, the '562 specification itself is written for a reader comfortable with "multi-dimensional classification or cluster analysis."

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2. The claim architecture (cross-reference; not repeated here)

Per the prior section: four independent claims — 1, 3, 6, 7 — all in Beauregard form ("computer readable medium storing an assay database") or its "machine readable assay database, stored in a storage device" variant. Reduced to elements:

The salient point for § 103: every independent claim is a data-structure claim. The claim does not require any bead, any fluorochrome, any laser, or any reaction. It requires the tables and the tree. Consequently, the obviousness case must be built on (i) the information content that the tables must carry — which is supplied wholesale by the wet-lab prior art — and (ii) the act of encoding that information as tables and a decision tree — which is supplied by the pattern-recognition and data-processing art.

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3. The prior art on the record

3(a) References I verified are cited in the '562 / sibling family

These are drawn from the '562 PDF citation line and the US 5,981,180 PDF (both retrieved):

3(b) Art I identified but did not independently verify against the '562's own IDS

• Horan & Wheeless, "Quantitative single cell analysis and sorting," Science (1977) — the earliest FMIA demonstration (rheumatoid factor on IgG-coated microspheres). Cited in the McHugh & Fulwyler chapter text I retrieved.
• McHugh, "Flow Cytometry and the Application of Microsphere-Based Fluorescence Immunoassays," Immunochemica 5:116 (1991).
• McHugh et al., "Development of a microsphere-based fluorescent immunoassay… Candida albicans," J. Immunol. Methods 116:213–219 (1989).
• EP 0 594 763 B1 — a microsphere-immunoassay patent whose specification (retrieved excerpt) discusses conventional FMIA and cites Fulwyler & McHugh and Shapiro. I have not confirmed its assignee, priority, or exact 102(b) status; treat as a lead to verify, not as established art.
• US 5,073,498 / EP 511,314 (Schwartz & Repollet) — uniform fluorescent microbead populations for instrument alignment; appears in a third-party reference list (EP 2982963).
• US 5,194,300 (Cheung) — production of fluorescent microspheres; same source.

3(c) The pattern-recognition / data-structure art (the second half of every combination)

This category is not speculation — the '562 specification hands it to us. The specification states, in terms:

"This step, in principle and practice, is a problem of multi-dimensional classification or cluster analysis. Many prior art techniques and commercial software programs exist to perform this task." (Google Patents, US6449562B1)

That is a binding admission that the discrimination step was known and routinized. To it add:

• Fisher, "The use of multiple measurements in taxonomic problems," Annals of Eugenics 7:179–188 (1936) — linear discriminant analysis. The '562 specification itself invokes "Fisher's linear discriminant technique," confirming the technique was a named, available prior-art tool.
• Duda & Hart, Pattern Classification and Scene Analysis (Wiley, 1973) — multi-dimensional classification, decision boundaries.
• Breiman, Friedman, Olshen & Stone, Classification and Regression Trees (1984); Quinlan, "Induction of Decision Trees," Machine Learning 1:81–106 (1986) — decision trees as a formalized classification structure.
• Lookup tables / pre-computed decision tables, and relational database tables generally — long-notorious, In re Venner, 262 F.2d 91 (CCPA 1958) (routine programming is not inventive).
• Flow-cytometer vendor analysis software contemporaneous with the priority date (Becton-Dickinson Consort 30 / LYSYS II / SimulSET, Coulter Epics / Elite workstation software) implementing region gates and population statistics.

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4. The obviousness case — combinations

Combination A — the core combination invalidating claims 1, 6, 7 (and claim 3 in part)

(PA-2 Fulwyler & McHugh 1990 ∪ PA-4/PA-5 McHugh 1988/1993) + (PA-10 Shapiro 1995) + Fisher/Duda-Hart decision-tree art + routine database tabulation.

For claim 3 specifically, the additional elements map as:

• interpretation test-type token → the choice among assay formats (competitive vs. sandwich; cutoff vs. ratio) — PA-5 discusses homogeneous vs. heterogeneous and competitive formats expressly;
• interpretation table of textual descriptions → routine — clinical laboratory reporting of qualitative results ("positive"/"negative"/"equivocal") from numeric cutoffs was standard in clinical chemistry;
• results table for statistical accumulation → PA-5: "the mean or mode of the fluorescent peak is used as the measure of signal intensity," computed per population; the '562's own F_m averaging of classified beads is the same act.

Combination B — invalidating claim 7 (the broadest independent claim)

Claim 7 drops the fluorescence-intensity and real-time limitations. Its elements are (a) a discriminant-function table with a decision tree over any classification parameter, and (b) an assay-definition table with a baseline measurement value. This is the weakest claim in the patent.

• PA-4 alone (McHugh 1988, 5 µm vs. 7 µm microspheres separated by forward light scatter) plus PA-10 (Shapiro on gating) discloses classification of particles into subsets by a non-fluorescence parameter.
• Substituting a fluorescence parameter for scatter requires no new art — PA-1 already discloses it, so elements of claim 1 are subsumed.
• The "table" and "decision tree" recitations collapse into In re Venner routine programming.

I regard the § 103 challenge to claim 7 as strong; to claims 1 and 6 as moderate-to-strong; to claim 3 as moderate (claim 3's four-table architecture is the most specific and the least directly anticipated).

Combination C — supplying the baseline/threshold element explicitly

If an argument is made that PA-4/PA-5 do not store a "baseline assay measurement value":

(PA-2 ∪ PA-4) + standard immunoassay-kinetics/quantitation texts already cited in the family, i.e., Odell & David, Principles of Competitive Protein-Binding Assays, 2d ed., pp. 243–247 (1983) and Harlow & Lane, Antibodies: A Laboratory Manual, p. 353 (1988) — both appear as non-patent citations in the related Luminex patent record (https://patents.google.com/patent/[US7465538](/patent/US7465538)). These teach calibrators, standard curves, and cutoffs, i.e., exactly a stored baseline value used to interpret a measured result.

Combination D — supplying the genetic/DNA embodiment's substance

Not necessary for validity of the claims as written (the claims do not recite DNA), but if any dependent claim is construed to require a nucleic-acid application: (PA-7 Vlieger 1992) + (PA-8 Yang 1995) + (PA-5 McHugh & Fulwyler 1993) — the first two teach hybridization-based quantitation of amplified DNA with fluorescent detection; the third teaches doing that on gated microsphere populations.

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5. Motivation to combine — why a POSITA would have done this

This is where the analysis is strongest, because the motivation is supplied by three independent sources, satisfying KSR on any of them.

(i) The problem itself created the demand. PA-2/PA-4/PA-5 promise multiplexing: "multiple analytes in one assay tube." Once you increase the number of subsets beyond the color/size resolution limit, the human analyst can no longer hand-gate populations in real time — an automated classifier is the only way to realize the promise the references themselves make. KSR: "the improvement is a predictable use of prior art elements according to their established functions."

(ii) The specification concedes the classification step was conventional. "Many prior art techniques and commercial software programs exist to perform this task." A patentee who admits the technique was available and commercially implemented cannot, under KSR, obtain a monopoly on storing the results of that technique in a table.

(iii) Data-rate physics forced the table structure. The '562 specification states the FACScan "can transmit a 16-bit (2 byte) word every 4 microseconds resulting in burst data rates of 500,000 bytes per second," and that processing must sustain "at least 32,000 bytes per second." At that rate, re-computing classification boundaries on the fly is not feasible — pre-computing the discriminant functions and storing them as a table indexed by classification parameter is the natural, indeed the necessary, engineering choice. That is a classic KSR "design incentive": the claimed table is the predictable optimization a POSITA would adopt.

(iv) The tables are merely a data model for information the references already require the operator to know. "Assay definition" is nothing more than the manifest of which bead subset carries which antigen — which must exist in any multiplexed kit. "Interpretation table" is the manifest of which numeric cutoff means "positive." Capturing an existing laboratory workflow as relational tables is In re Venner routine programming and, post-KSR, an obvious application of a general-purpose computer to a known process (Alice/Mayo § 101 concerns are separate and are not part of a § 103 analysis, but they underscore the generality of the structure).

(v) The commercial-software cue. Because flow-cytometer vendors were already shipping region-gating analysis packages (BD Consort/LYSYS II, Coulter Epics), a POSITA implementing the same classification in a new instrument's firmware would have had every reason to encode the gates as a stored table/tree rather than as hard-coded branches.

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6. Anticipated rebuttals and where they actually bite

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7. Timing landmines — art that looks usable but is not prior art

This is important because a careless searcher will produce it and a competent one will discard it. Under the 1996-10-10 critical date:

• US 6,592,822 / US 7,267,798 / CA 2,640,578 A1 — "Multi-analyte diagnostic system and computer implemented process for same" (Luminex) — filed 1998-05-14. Despite being screamingly on-point for these claims (retrieved excerpt describes real-time bead classification, bead statistics, FL1 mean/SD/CV/peak computation, and templates storing "gates, reagents, bead set values, detection regions, and spectral overlap compensation settings"), it post-dates the '562 priority date and is not § 102/§ 103 prior art to the '562 claims. It is, however, useful § 112 written-description context and useful evidence of what was conventional in the field, and it is a later Luminex patent — so citing it as § 103 art would be an error.
• McHugh et al., Cytometry 29:106–112 (1997) (HCV microsphere immunoassay) — received 11 April 1997. Post-dates the priority date; usable only as evidence of the state of the art, not as § 102 art.
• Kettman et al., Cytometry 33:234–243 (1998) and Oliver et al., Clin. Chem. 44:2057–2060 (1998) — the "64 multiplexed microsphere sets" work. Post-dates the priority date. This is the classic trap, because a casual search will surface these as the first description of the 64-subset system — but they are the patentee's own later publications, not prior art.
• WO 1999036564 A1 — same title as the '562 ("Multiplexed analysis of clinical specimens apparatus and methods") and contains verbatim the '562's specification language. This is a family member, not prior art. Do not cite it against the '562.
• US 6,514,295 / US 6,599,331 / US 6,632,526 ("precision fluorescently dyed particles") — Luminex family; the EP 2 982 963 reference list dates WO 99/19515 to the 1998–99 window. Not prior art to the '562 claims.

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8. Bottom line

1. The § 103 attack on the '562 claims is viable and, in my assessment, likely to succeed against independent claims 6 and 7, and reasonably likely to succeed against claim 1. Claim 3 is the most defensible and would require the fullest combination (Combination A + C, plus clinical-lab reporting art).
2. The core combination is: Fulwyler US 4,499,052 + Fulwyler & McHugh, Methods in Cell Biology 33:613–629 (1990) + McHugh & Fulwyler, Clinical Flow Cytometry 535–544 (1993), taken with Shapiro, Practical Flow Cytometry (3d ed. 1995), and further in view of Fisher (1936) and the Duda & Hart (1973) / Breiman CART (1984) / Quinlan ID3 (1986) decision-tree literature — the latter category being admitted to be prior art by the '562 specification's own words.
3. The motivation is over-determined: (a) the references' own multiplexing promise requires automated classification; (b) the spec admits the classification technique was conventional; (c) the 500,000 byte/sec data rate makes pre-computed, stored discriminant functions the necessary design; (d) the tables merely model information any multiplexed kit must already carry.
4. Nothing in the retrieved record shows that the '562 patent was ever actually challenged (no IPR, no reexam, no litigation asserted on it — consistent with the earlier Litigation summary). The claims therefore carry a statutory presumption of validity under 35 U.S.C. § 282, and any § 103 challenge must overcome it with clear and convincing evidence — a materially higher bar than the "would have been obvious" analysis above reflects.

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9. What I could not do, and what would close the gaps

• I could not retrieve the '562's own "References Cited" / "Cited By" tables, because the Google Patents text supplied was truncated and my searches did not surface the PDF's citation column. The authoritative source is the granted patent front page: http://patentimages.storage.googleapis.com/13/c9/17/8a118c7d6a5209/[US6449562](/patent/US6449562).pdf — and the USPTO "References Cited" tab at https://patents.google.com/patent/US6449562/en.
• Dependent claims 2, 4, 5, 8–13 are unverified verbatim. A full § 103 opinion requires each dependent limitation mapped separately; several (e.g., those adding light-scatter classification parameters or format specifics) are likely more vulnerable than the independents, not less.
• I did not verify the assignee/priority/102(b) status of EP 0 594 763 B1, nor did I confirm the date of US 5,073,498 and US 5,194,300 as against the 1995-10-10 § 102(b) date. These are leads, not established art.
• The recommended authoritative steps remain: a USPTO PatentCenter/PAIR file-wrapper pull for the '562 to obtain the IDS of record, and an OCE Patent Litigation Dataset query (patent_number = 6449562) to confirm the negative litigation finding.