US 5837832

I'll verify this patent against live sources before summarizing.

US 5,837,832 — verified summary

Search scope note up front: I ran web searches against public patent databases (Google Patents, USPTO.report, OSTI, Espacenet) for the exact number 5837832. I did not find any CAFC 2026 docket entry, appeal, or 2026 litigation involving US 5,837,832. Its recorded legal status is "Expired – Lifetime" with an anticipated expiration of 2015‑11‑17 (Google Patents), which is consistent with no 2026 Federal Circuit activity. I could not run a native USPTO Patent Center or CAFC docket query from this session — only web search — so treat "no CAFC 2026 activity" as a search result, not a certified negative. I found no results for any similar but different number, and I have not substituted one.

Bibliographic data (consistent across all sources consulted)

Sources: https://patents.google.com/patent/US5837832/en ; https://uspto.report/patent/grant/5837832 ; https://www.osti.gov/biblio/871979

Abstract (as issued)

"DNA chips containing arrays of oligonucleotide probes can be used to determine whether a target nucleic acid has a nucleotide sequence identical to or different from a specific reference sequence. The array of probes comprises probes exactly complementary to the reference sequence, as well as probes that differ by one or more bases from the exactly complementary probes."

What the patent actually covers (plain language)

The patent describes "tiling": building a bound array of short oligo probes that collectively walk along a known reference sequence (one probe per base, overlapping), plus, for each position, a set of matched probes in which the base at a chosen "interrogation" position is substituted by each different nucleotide. Hybridizing a labeled target and comparing signal intensities across the matched/mismatched probes lets you call the target's sequence, detect single‑base substitutions, deletions and insertions, and read heterozygotes (mixtures show two bright probes). Worked examples include CFTR exon 10 (ΔF508, G480C), human mitochondrial D‑loop, p53 exons 5 and 6, and HIV reverse transcriptase drug‑resistance mutations; fabrication is by VLSIPS™ light‑directed synthesis on silica/glass chips.

Independent claims

The issued patent has one independent claim (claim 1); claims 2–18 all depend from it. (Claim text as reproduced at https://uspto.report/patent/grant/5837832 and cross‑checked against the Google Patents full text; for authoritative wording use the USPTO Patent Center copy.)

Claim 1 — plain-language overview:
A physically immobilized probe array on a solid support with a controlled size and composition:

• Size/format: at least 100 but no more than 100,000 different oligonucleotide probes, each 9–20 nucleotides long, each occupying its own separate, known site.
• Content — at least four probe sets:

1. a first set whose members are exactly complementary to a reference sequence, and which completely span that reference sequence with probes that overlap one another (i.e., the tiling, wild‑type set); and
2. three additional sets, each identical to the first set in sequence except at a different nucleotide — that substituted nucleotide sits at the same position in every member of all three additional sets, but is a different nucleotide in each of the three sets (the classic three‑mismatch interrogation sets).

Plainly: it claims the tiled array architecture itself — a complete covering set of perfect matches plus three position‑specific single‑base variant sets, in a chip with 100–100,000 distinct 9–20‑mers — not the specific biological target and not the synthesis chemistry.

No other independent claim exists. Notably, claim 1 does not itself require the fourth/duplicate "wild‑type substitution" set; that is added only in claim 2 ("a fourth additional set of probes, which fourth additional set is identical to probes in the first set") — i.e., the five‑lane scheme described in the specification.

Key dependent claims (short overview)

• 2 — adds a fourth additional set identical to the first set (completing the 4‑substitution/5‑lane arrangement).
• 3 — reference sequence is double‑stranded and probes for both strands are present.
• 4–5 — probes 12–17 nt; specifically 15‑mers attached at the 3′ end with the substituted nucleotide at position 7 from the 3′ end.
• 6–8 — CFTR exon 10 application (1,000–100,000 probes, 10–18 nt); claims 7 and 8 recite specific probe sequence sets (SEQ ID NOs 302–310 and 9–17, each with "X" = A, G, C, and T, four probes per set).
• 9–10 — mitochondrial D‑loop application; claim 10 specifies 15‑mers, position‑7 substitution, 3′ attachment, region bounded by positions 16280–356, and 2,500–100,000 probes.
• 11–13 — p53 application; claim 12 = ≥60 contiguous nt from exon 6; claim 13 = exon 5, 17‑mers, position 7.
• 14–15 — probes are oligodeoxyribonucleotides; array size 10,000–100,000.
• 16–17 — HIV application, specifically the reverse transcriptase gene.
• 18 — probes immobilized via a linker.

Points of uncertainty / caveats

1. Claim text source. The claim set above comes from a third‑party host (uspto.report) that reproduces the printed patent, and its substance matches the Google Patents description. I have not verified it against the USPTO official image/Patent Center record in this session. Confirm before relying on exact wording.
2. Oddity worth flagging: the patent's own figure descriptions refer to the SEQ ID NOs in FIGS. 2–8, 17, 20, 21, 27 as "peptide sequences," although the sequence listing shows them to be nucleic acid sequences. This appears to be an error in the printed text; any SEQ‑ID‑based claim construction should account for it. I am not auto‑correcting it.
3. Priority/filing nuance (be careful when citing dates): the priority date is 1993‑06‑25, but the patent's own filing date is 1995‑05‑16 as a continuation of an application filed 1993‑10‑26. If you need a §102/§120 date, use the specific application in the chain, not just the 1993 priority claim.
4. No CAFC 2026 docket located. Search results returned unrelated 2026 Federal Circuit/district docket material, none naming 5837832. Given the 2015 expiration, an active 2026 CAFC appeal on this patent is very unlikely, but I cannot certify the absence from a patent‑only search.

I'll search for litigation involving US patent 5837832 across multiple sources.

Let me search litigation-specific databases and sources.

Summary of Findings

Bottom line: I did not find any confirmed litigation that specifically names U.S. Patent 5,837,832. I want to be explicit about this and about the limitations of what I could verify.

Key facts about the patent (from the authoritative full text you provided)

The expiration date is significant: any infringement litigation would have had to be filed and resolved before November 2015.

Search results

My searches (including queries targeting the patent number, Affymetrix litigation, and litigation-portal content) surfaced mostly patent-citation noise — i.e., other patents and published applications citing 5,837,832 as prior art (EP1945761B1, WO2001046461A3, EP2629094A1, EP3990920, GB2373500A, and various Justia patent pages). None of these are litigation records.

I was not able to retrieve a direct hit from:

• Unified Patents' litigation caselist,
• PACER / CourtListener docket records, or
• the Federal Circuit / District Court opinions

that names 5,837,832 as a patent-in-suit.

Important caveats

1. Search-steps limitation. My tool calls were capped before I could exhaustively query the litigation-specific databases you named, so I cannot represent this as an exhaustive negative.

2. The searches did surface the general Affymetrix litigation landscape, which is relevant context but not confirmation that '832 was asserted:

   • Affymetrix, Inc. v. Illumina, Inc. — filed July 26, 2004, U.S. District Court for the District of Delaware. The complaint asserted six Affymetrix patents against Illumina's BeadArray products. Jury found infringement of five patents on March 13, 2007 (damages ~$16.7M); validity/enforceability tried in later phases. A related case, Affymetrix, Inc. et al v. Illumina, Inc., No. 3:11-cv-00184 (W.D. Wis.) was filed March 14, 2011. However, the reports I retrieved do not identify 5,837,832 as one of the six asserted patents — those six are generally reported as the '934, '305, '992, '138, '776, and '432 patents. I could not verify the asserted patents by number, so I do not assert that '832 was in that suit.
   • Affymetrix, Inc. v. PE Corp. (NY), 219 F. Supp. 2d 390 (S.D.N.Y. 2002) — this is Affymetrix as plaintiff, but based on the Carruthers patents (the '066, '707, '418, '319, and '679 patents) in a contract/antitrust/enforceability dispute — not '832.
   • Oxford Gene Technology v. Affymetrix (UK and Delaware) — arose from the Southern microarray patents and was about Oxford's patents against Affymetrix, not '832.

What you should do to close the gap

To get an authoritative answer, a direct patent-number search in the following would be needed:

• Unified Patents litigation caselist (https://portal.unifiedpatents.com/litigation/caselist) — search for 5837832,
• Docket Navigator / Lex Machina / RPX — patent-number and party filters,
• PACER across likely districts (D. Del., N.D. Cal., D. Mass., W.D. Wis.),
• USPTO Assignment records and PTAB (though IPRs post-date the 2015 expiry for this patent).

I could not complete those direct queries within my search budget, so I am flagging this as a verified negative only within the sources I could reach, not a global negative. I would rather tell you I don't know with confidence than assert a case that I cannot ground in a specific docket number.

AIA Trial Proceedings — US 5,837,832 ("Arrays of nucleic acid probes on biological chips")

Search basis: The canonical list is the structured "PTAB proceedings on file" block in this prompt, sourced from the USPTO Open Data Portal (ODP) API: it returns no AIA trial proceedings for this patent. I supplemented that with targeted web searches for the patent number paired with IPR/PGR/CBM/PTAB terms, petitioner names, and the Affymetrix / Unified Patents litigation landscape. I could not run a native PTAB E2E (PTACTS) or Docket Navigator query from this session — only web search — so treat the negative below as verified across reachable sources, and re-verify at the links in "Recommended next steps."

Proceedings overview

Total AIA trial proceedings on US 5,837,832: 0. Breakdown: 0 active, 0 claims invalidated, 0 claims sustained, 0 settled, 0 institution denials — there is nothing to break down. Defensive posture: a defendant has no PTAB win to point to and no IPR estoppel to worry about — but more importantly, the patent itself is dead. Per Google Patents, legal status is "Expired – Lifetime" with an anticipated expiration of 2015-11-17, and the current assignee pays no maintenance annuity on it. An IPR defense is therefore not the right tool for anyone facing a demand letter on this patent; the right tool is the expiration-and-damages-window argument in "Strategic summary" below.

No proceedings to report

The instruction is not to invent proceeding numbers, and I will not. There are no IPR, PGR, or CBM dockets to describe for US 5,837,832. Two enabling conditions explain the emptiness, and both are worth understanding rather than treating as an accident:

1. AIA trials post-date most of this patent's commercially relevant life. The AIA trial regime opened on 2012-09-16 (first IPR petitions). US 5,837,832 issued 1998-11-17 from an application filed 1995-05-16 (continuation of the 1993-10-26 application, CIP of the 1993-06-25 application). By the time IPR became available, the patent had roughly three years and two months of enforceable term left (to 2015-11-17). An IPR takes about 12 months from institution plus ~6 months to institution, leaving a very thin window in which a challenger could obtain a cancellation of any practical value.
2. The patent owner was an operating-company plaintiff, not an NPE target. On the searchable record, Affymetrix used its array patents offensively (e.g., Affymetrix, Inc. v. Illumina, Inc., D. Del., filed 2004-07-26, and the related W.D. Wis. action, No. 3:11-cv-00184, filed 2011-03-14). The defensive aggregators and defendants who fuel the IPR docket had no reason to petition against a patent in the hands of an operating company that was not asserting this patent against them. Note, consistent with the litigation section above, the reported six patents asserted in the Illumina action do not include 5,837,832 — I could not verify the asserted numbers, so I neither confirm nor deny.

PGR is categorically unavailable: PGR applies only to patents issuing from applications filed on or after 2013-03-16 (35 U.S.C. § 321). This patent's earliest effective filing is 1993–1995.
CBM is unavailable/inapplicable: the transitional CBM program sunset on 2020-09-16, and in any event the patent does not claim a "financial product or service" method.
No Federal Circuit appeals from a PTAB FWD exist either, because there was no FWD to appeal. (This is a different point from the search note in the earlier litigation section that I found no CAFC 2026 docket entry naming 5,837,832.)

Search result set (things that are not PTAB matters, flagged so they aren't mistaken for them):

• EPO Board of Appeal decision T 1509/09, concerning European patent 0 853 679 (Affymetrix, gene-expression monitoring) — a different patent, a different office, and an opposition/appeal, not an AIA trial. Do not conflate it with US 5,837,832.
• Numerous third-party patents and EPO filings citing US 5,837,832 as prior art (EP1945761B1, WO2001046461A3, EP3990920, RU2478716C2, US20040180365A1, etc.) — citation noise, not challenges to this patent.
• Affymetrix, Inc. v. PE Corp. (NY), 219 F. Supp. 2d 390 (S.D.N.Y. 2002) — the Carruthers-line patents, not '832.

Strategic summary

Claim status across all PTAB activity: claims 1–18 are UNTESTED before the PTAB — none canceled, none sustained, none narrowed. Every claim remains exactly as issued on 1998-11-17. There is no FWD to quote, no certificate of cancellation or confirmation to link, and therefore no claim-level disposition of this patent exists at the PTAB. Nothing in this report should be read as a statement about claim validity on the merits; no tribunal in the reachable record has adjudicated it.

Estoppel landscape: essentially nil, and irrelevant. Because no IPR was ever instituted, 35 U.S.C. § 315(e)(2) estoppel binds no one on this patent — no petitioner, no privy, no real party in interest. If a defendant were weighing a validity challenge today, every § 102/§ 103 ground would be formally "still available." Practically, though, the more decisive obstacle is not estoppel but 35 U.S.C. § 286: damages reach back only six years before suit, and the patent expired 2015-11-17. Any recovery is therefore capped at acts of infringement occurring roughly between late 2009 and 2015-11-17, and any suit filed today would be asserting an expired patent whose claims cannot support prospective injunctive relief. A demand letter that ignores expiration is the real vulnerability — not prior art.

Pattern signals: none to read. There is no repeat petitioner (no one petitioned twice, because no one petitioned once), no patent owner aggressively defending at the Board (nothing to appeal), and no defensive aggregator such as Unified Patents in the chain. The absence of PTAB activity on a patent this foundational is itself informative: it tells you the patent was held and enforced by an operating company during the years when IPR volume peaked, rather than being monetized by an NPE that would have drawn a Unified Patents or member-funded challenge. If a demand letter on '832 surfaces now, that pattern has changed — which is a fact worth probing in itself (chain of title, reissue/continuation activity, and whether the demand is aimed at later-issued Affymetrix-family patents that carry a post-2013-03-16 filing date and are therefore PGR/IPR-eligible).

Recommended next steps

1. If you are a defendant and you were hoping for an invalidated claim to cite: there isn't one. Do not represent to opposing counsel or a court that any claim of 5,837,832 has been canceled — it has not. Your defensive theory is expiration, not invalidity:

• Google Patents legal status and "Anticipated expiration 2015-11-17": https://patents.google.com/patent/US5837832/en
• Damages window: 35 U.S.C. § 286 (six-year lookback) combined with the 2015-11-17 expiry.
• Also check for prosecution laches exposure if the patent is being asserted against late entrants: the '832 chain includes a 1993-06-25 priority application, a 1993-10-26 continuation, a 1995-05-16 filing date, and a 1998-11-17 issue date — a roughly five-year pendency that is worth developing if the accused acts are old.

2. If you want to confirm the zero-PTAB finding yourself (recommended — I could not run these directly):

• USPTO PTAB E2E / PTACTS party-and-patent search, entering 5837832 or 5,837,832: https://ptacts.uspto.gov/
• USPTO PTAB API (structured, no UI): https://developer.uspto.gov/ptab-api
• USPTO Patent Center for the file history and any ex parte reexamination or reissue activity (a non-AIA route that the ODP AIA-trial data would not surface): https://patentcenter.uspto.gov/
• CourtListener for any CAFC appeal from a PTAB decision naming this patent (expected: none): https://www.courtlistener.com/
• PTAB statistics for context on why an old, operating-company-held patent attracts no petitions: https://www.uspto.gov/sites/default/files/documents/trial_stats_december_2025.pdf

3. If you are evaluating a live assertion, redirect the diligence. Because no AIA trial exists, the PTAB is a dead end — spend the effort on (a) the expiration date and § 286 window, (b) chain of title from Affymetrix to whoever is asserting it, and (c) whether the demand actually rests on a different, later-filed member of the family (e.g., the applications recorded as priorities on 2002-03-28 and 2002-08-27 leading to US 20030134291A1 and US 20030054393A1) — those would be IPR/PGR-eligible and would change this analysis entirely.

4. Caveats I will not paper over. The negative above rests on the ODP structured block (canonical) plus web search. I did not execute native PTACTS, Docket Navigator, or Lex Machina queries, and my search budget was exhausted before I could run an ex parte reexamination check. It remains possible, though I found no evidence, that a non-AIA ex parte reexamination or a pre-issuance challenge exists outside the AIA-trial record. If a specific proceeding number is put in front of me, I will verify it rather than assume; I have not fabricated any.

I'll verify the assignment record against live sources before reconstructing the chain.

Let me try to pull the exact Assignment Center record (reel/frame and correspondent) for this patent specifically.

I've reached my search budget. Here is the ownership-chain reconstruction, with a clear separation between what the records establish and what I could not verify.

Inventors

Nine named inventors (all co-inventors on a single assignee chain — this is a corporate team invention, not an independent-inventor filing):

Basis for the employer column, and its limits. The only hard record I have is the 1996-08-26 assignment executed by Affymax Technologies N.V. (the assignor), which establishes that the invention rights were held by Affymax at filing and passed as a corporate transfer. I do not have the individual inventor employment/assignment instruments (the "ASSIGNMENT OF ASSIGNORS INTEREST" document itself) in front of me, so I am not asserting individual employment-contract details I cannot cite.

Unusual-pattern check — NOT PRESENT. I found no evidence that the inventors departed the original assignee within 12 months of filing. This is a normal corporate research-team filing: several of these inventors appear on Affymetrix's contemporaneous VLSIPS/GeneChip filings (e.g., US 5,968,740 Fodor et al.; US 5,858,659 Sapolsky et al.; US 5,856,101 Hubbell et al.), which is inconsistent with a rapid mass departure. I would rather flag this as no signal than infer a fire-sale precursor from nothing.

Original assignee

Affymetrix, Inc. — but with an important ownership nuance that the patent's front page obscures:

• The patent's "Original Assignee" field reads Affymetrix, Inc., yet the first recorded conveyance is a 1996-08-26 assignment from Affymax Technologies N.V. to Affymetrix, Inc. That means the original holder of this application was Affymax Technologies N.V. (a Netherlands-Antilles/Curaçao entity), not Affymetrix. Affymetrix was incorporated in California in 1992 as a subsidiary of Affymax, and the '832 application (filed 1995-05-16) sat inside that pre-spin-off structure. This is a genuine discrepancy between the front-page assignee and the recorded chain, and I am flagging it rather than smoothing it over.

• Line of business / product: Yes — Affymetrix shipped products embodying the claims. Its GeneChip® oligonucleotide arrays (intro­duced commercially in 1996, first with the HIV probe array) are exactly the "DNA chips" of the '832 specification, and the tiling/mismatch architecture of claim 1 is the operating principle of those products. Affymetrix was a genomics/life-science tools company (Santa Clara, CA; NASDAQ: AFFX).

• Current status: Operating, but no longer independent. Affymetrix was acquired by Thermo Fisher Scientific on 2016-03-31 for ~$1.3 B ($14.00/share cash), after absorbing a competing bid from Origin Technologies. Affymetrix ceased trading on NASDAQ and was folded into Thermo Fisher's Life Sciences Solutions segment. Affymetrix operates today as a Thermo Fisher brand/subsidiary. (Sources: Thermo Fisher/Affymetrix 8-K Ex-99.1, 2016-03-31, https://getfilings.com/sec-filings/[160331](/patent/160331)/THERMO-FISHER-SCIENTIFIC-INC_8-K/d159278dex991.htm; CSHL LiWki Affymetrix profile.)

  • Pre-history: Glaxo purchased Affymax in March 1995 (~$500 M), which carried Affymax's ~65% stake in Affymetrix; Affymetrix held its own IPO in June 1996.

Assignment timeline

Sourcing caveat up front (read this before the entries). I could not open the USPTO Assignment Center (https://assignmentcenter.uspto.gov/) or the assignment index (https://assignment.uspto.gov/patent/index.html) directly in this session — my tools were web-search only, and the searches returned citation noise rather than the Assignment Center page for this patent. The dates, conveyance types, and assignor/assignee names below come from the authoritative Google Patents "Legal Events" feed for US 5,837,832 itself, which is derived from USPTO assignment records. Reel/frame numbers and the correspondent of record are NOT in that feed, and I could not retrieve them for this patent. Where I cite reel/frame below I mark them [UNVERIFIED — sibling portfolio] because I obtained them from Espacenet INPADOC records for sibling Affymetrix patents (US 5,510,270 and US 5,593,839), not for '832; a family-block guess is not a record and must be confirmed by number at the Assignment Center.

Recorded events, chronological:

• 1996-08-26 (recorded) — Reel/Frame [UNVERIFIED — sibling portfolio: possibly 008105/0657 or 008955/0530]

  • Conveyance: Assignment of Assignors Interest
  • Assignor: AffyMax Technologies, N.V.
  • Assignee: Affymetrix, Inc.
  • Correspondent: not retrieved (could not access Assignment Center)
  • Context: Transfer-to-spin-off — the DNA-chip program moves out of the Affymax (Glaxo) nest into Affymetrix as it prepares to stand alone. Not a fire-sale; a planned corporate separation.

• 1998-12-23 (recorded) — Reel/Frame [UNVERIFIED — sibling portfolio: 009662/0497]

  • Conveyance: Merger
  • Assignor: Affymetrix, Inc., a Corp. of CA
  • Assignee: Affymetrix Inc., a Corp. of DE
  • Correspondent: not retrieved
  • Context: Internal reorg / change of domicile only — California Affymetrix merged into a Delaware Affymetrix. Ownership does not leave the Affymetrix enterprise. (This is the single most common "assignment" pattern that gets misread as an NPE transfer; it is not one.)

• 2012-06-27 (recorded) — Reel/Frame [UNVERIFIED — sibling portfolio: 028465/0541]

  • Conveyance: Security Agreement
  • Assignor: Affymetrix, Inc.
  • Assignee: General Electric Capital Corporation, as Agent
  • Correspondent: not retrieved
  • Context: Securitization / secured lending — GE Capital takes a security interest in Affymetrix's IP as loan collateral. The patent is encumbered, not sold; Affymetrix remains owner. (Consistent with the 2012 convertible-notes financing environment around Affymetrix.)

• 2015-10-28 (recorded) — Reel/Frame [UNVERIFIED — not retrieved; no sibling number found]

  • Conveyance: Security Interest
  • Assignor: Affymetrix, Inc.
  • Assignee: Bank of America, N.A., as Administrative Agent
  • Correspondent: not retrieved
  • Context: Securitization — a second lender takes a security interest, layered on top of the GE position ahead of the Thermo Fisher deal.

• 2015-11-13 (recorded) — Reel/Frame [UNVERIFIED — sibling portfolio: 037109/0132]

  • Conveyance: Release by Secured Party
  • Assignor: General Electric Capital Corporation, as Agent
  • Assignee: Affymetrix, Inc.
  • Correspondent: not retrieved
  • Context: Lien release — GE's security interest is discharged (the encumbrance is lifted), returning clean title to Affymetrix.

• 2016-04-05 (recorded) — Reel/Frame [UNVERIFIED — not retrieved]

  • Conveyance: Notice of Release
  • Assignor: Bank of America, N.A., as Administrative Agent
  • Assignee: Affymetrix, Inc.
  • Correspondent: not retrieved
  • Context: Lien release — BofA's security interest is discharged. This is the last recorded assignment-type event on '832.

Two gaps I want to state plainly, not paper over:

1. There is no recorded assignment to Thermo Fisher Scientific (or to Life Technologies) on this patent's event feed. The 2016 Thermo Fisher acquisition closed 2016-03-31, but the final recorded event for '832 is the 2016-04-05 BofA release, not a merger/assignment to a Thermo entity. The likely explanation is that '832 stayed titled in Affymetrix, Inc., which became (and remains) a Thermo Fisher subsidiary — so a separate recordation wasn't necessary — but I cannot confirm that from the Assignment Center in this session. Anyone relying on "current owner of record" should verify whether the DE Affymetrix entity or a Thermo Fisher entity is the record owner.

2. Correspondent of record was not obtainable. This is the single most diagnostic field for your task and I could not retrieve it. I have not inferred, substituted, or guessed an attorney name.

Timeline diagram

timeline
    title Ownership of US 5837832
    1993 : Priority application filed
    1995 : Continuation filed
         : Held by Affymax Technologies NV
    1996 : Assigned to Affymetrix Inc
         : Affymax to Affymetrix separation
    1998 : Patent granted
         : Delaware reincorporation merger
    2012 : Security agreement to GE Capital
    2015 : Security interest to Bank of America
         : GE Capital lien released
    2016 : Bank of America lien released

NPE / troll-pattern signals

1. Shell-entity transfer — NOT PRESENT. Every assignee in the chain is a real operating company or a real secured lender: Affymax Technologies N.V., Affymetrix Inc. (CA and DE), General Electric Capital Corporation, Bank of America N.A. No "IP/Holdings/Licensing/Ventures" suffix appears anywhere in the recorded chain. The 2012/2015 events are security interests, whose assignees are lenders taking collateral — the patent never leaves Affymetrix ownership, and both liens are released in 2015–2016.

2. Known asserter in the chain — NOT PRESENT. None of the recorded assignees (Affymax, Affymetrix, GE Capital, Bank of America, and in substance Thermo Fisher) matches Acacia, Marathon Patent Group, Intellectual Ventures, IPNav, Wi-LAN, Mosaid/Conversant, Vringo, Pendrell, Innovatio, MPHJ, Lumen View, Round Rock, Document Generation Corp, or any Spangenberg entity. Affymetrix is the counterparty these entities sue, not a member of that class.

3. Repeat correspondent across the chain — UNCLEAR / NOT DETERMINABLE. I could not retrieve the correspondent of record for any '832 event, so I cannot test for a recurring filing attorney. I note (without asserting it) that the four 2012–2016 recordings are lender-lien filings, which are typically recorded by each lender's counsel and would not be expected to share a correspondent with the 1996 assignment — but that is a hypothesis, not a finding, and this field needs a direct Assignment Center pull.

4. Cascading transfers — NOT PRESENT. The recorded transfers span 1996 → 2016 (≈20 years) and are not a rapid chained-LLC cascade. The closest cluster (2012–2016) consists of a lender lien, a second lender lien, and two lien releases — bookkeeping on encumbrances, not a chain of ownership hops. No two consecutive assignees share a suspicious address or principal.

5. Pre-litigation transfer — NOT PRESENT / NOT APPLICABLE. No assignment to a litigating entity within 6 months before any suit naming '832 is visible (and, per the earlier litigation section, no suit naming '832 was located). The only assignment in any pre-litigation window is the 1998 merger, which is 18+ years before expiration and unrelated to assertion.

6. Bankruptcy fire-sale — NOT PRESENT. No Chapter 7/11 of Affymax or Affymetrix appears in the record. The endpoints are the opposite of a fire-sale: Glaxo's ~$500 M cash purchase of Affymax (1995), Affymetrix's 1996 IPO, and Thermo Fisher's $1.3 B all-cash acquisition of Affymetrix (2016-03-31). This is a value-realization chain, not a distress chain.

7. Privateering — NOT PRESENT. No transfer from an operating company to an NPE that then asserts on the operating company's behalf. Affymetrix asserted its own patents directly (e.g., the Hyseq complaint filed 1997-03-04, and the Affymetrix v. Illumina matters), which is the opposite of privateering. I could not confirm that '832 itself was among the asserted patents, and I am not asserting that it was.

8. Defensive aggregator — NOT PRESENT. The chain does not terminate at RPX, AST, LOT, Unified Patents, or OIN. It terminates in an operating company (Affymetrix, within Thermo Fisher). No neutralization signal.

Verdict

Operating-company assertion.

Justification: the recorded chain is a clean, single-enterprise ownership line — Affymax Technologies N.V. → Affymetrix, Inc. (1996-08-26, Assignment of Assignors Interest), a domicile-only 1998-12-23 Merger from CA Affymetrix to DE Affymetrix, two secured-lender encumbrances (2012-06-27 GE Capital Security Agreement; 2015-10-28 Bank of America Security Interest) each followed by a release (2015-11-13; 2016-04-05), with no NPE, no shell LLC, no cascade, no fire-sale, and no defensive aggregator anywhere in the chain. The assignee shipped products practicing claim 1 (GeneChip® arrays) and litigated as a plaintiff rather than being a passive licensor. Two material caveats drive me to phrase this cautiously rather than with high confidence in either direction: (a) I could not verify reel/frame or the correspondent of record for '832 itself — the reel/frame numbers offered above are marked unverified and are borrowed from sibling patents — and (b) the final recorded event is a 2016 lien release, with no recorded assignment to Thermo Fisher, so the current record owner should be confirmed directly. Verify at https://assignmentcenter.uspto.gov/ by searching patent number 5837832 (and cross-check at https://patents.google.com/patent/US5837832/en#legalEvents).

I'll research the prior-art citations for US 5,837,832 across patent databases.

Let me search for the specific prior-art citation list on this patent.

I found an Espacenet "cited documents" lead. Let me pull the full citation list for 5837832.

Important scope caveat before the analysis

My tool budget was exhausted before I could pull the complete front-page "References Cited" table from a primary source (Google Patents' citation table, the USPTO Patent Center PDF, or Espacenet's full "cited documents" list). So what follows is not a verbatim transcription of the printed front page. It is a synthesis of three things I could verify:

1. references confirmed in the Espacenet "cited documents" record for US 5,837,832,
2. references cited by the patent's own "Description of Related Art" (from the authoritative full text in your message), and
3. family/related documents surfaced in search reports.

Where I am relying on general knowledge rather than a source I retrieved this session, I say so. I am not inventing citation rows to fill the table.

Per your strict rule, I have not substituted any similar number (e.g., US 5,831,042, US 6,317,832, US 6,660,234) for 5837832. References to those numbers in search results were noise from other patents' citation lists.

A. Two date facts that govern the whole §102 analysis

• Critical date for §102(b): If the claims are entitled to the earliest priority date in the chain — 1993‑06‑25 (Ser. No. 08/082,937) — then the one‑year §102(b) bar date is 1992‑06‑25. (The patent's own filing is 1995‑05‑16 as a continuation of 08/143,312 filed 1993‑10‑26.) As your own summary correctly flags, which §102 date applies depends on whether each claim gets the 1993‑06‑25 benefit.
• Consequently, references issued before 1992‑06‑25 are §102(b) art; references issued between 1992‑06‑25 and 1993‑06‑25 are §102(a)/(e) art only.

B. References cited (with what I could verify)

1. US 5,002,867 A — Macevicz, Stephen C.

• Title: "Nucleic acid sequence determination by multiple mixed oligonucleotide probes"
• Cited in: confirmed as a cited document in the Espacenet record for US 5,837,832; also recited in the patent's own "Description of Related Art."
• Priority/app. date: 1988‑04‑25; issued 1991‑03‑26 (date confirmed in search results).
• Status vs. priority date: §102(b) art (issued >1 year before 1992‑06‑25).
• Brief description: Determines nucleic‑acid sequence by hybridizing a target to multiple mixed oligonucleotide probes — a solution/support hybridization approach using populations of short probes, i.e., the "mixed probe" sequencing concept.
• Anticipation analysis (§102): This is the closest pure "probe‑set" reference. It discloses sets of oligonucleotides used to read sequence, which bears on the concept underlying claim 1's first set + substitution sets. However, it does not disclose a physically immobilized array in which each different probe occupies "a separate, known site" on a solid support, nor the recited 9–20 nt / 100–100,000‑probe architecture. On the record available, it does not anticipate claim 1; it is better characterized as §102/§103 art against the general probe‑set idea and the dependent application claims (e.g., claims 6–10's use of defined probe sequences), and it is the reference most likely to have been the examiner's §103 anchor.

2. US 5,202,231 — Drmanac et al.

• Title: "Method of sequencing of genomes by hybridization of oligonucleotide probes"
• Cited in: the patent's own "Description of Related Art" (listed together with US 5,002,867 and WO 93/17126 as prior proposals for using large numbers of probes to obtain complete sequence).
• Date: issued April 1993 (I did not re‑verify the exact day this session; commonly reported as 1993‑04‑13).
• Status vs. priority date: §102(a)/(e) art — issued after the 1992‑06‑25 §102(b) date but before the 1993‑06‑25 priority date. It is not §102(b) art if the 1993‑06‑25 date governs.
• Brief description: Sequencing by hybridization (SBH) using large arrays/sets of oligonucleotide probes to reconstruct a target sequence.
• Anticipation analysis: Directly relevant to the tiling/SBH premise of claim 1 (overlapping probes covering a known sequence). The patent itself characterizes this line of art as having "failed to provide an enabling method for using arrays of immobilized probes for this purpose." It likely does not anticipate claim 1's specific limitation requiring three additional sets each differing at the same position by a different nucleotide, but it is strong §103 art and would be a §102 candidate against any claim broadened to bare SBH arrays. Note the Drmanac patents are also the subject of the WO 95/09248 family cited in the WO 00/40758 search report below.

3. US 5,143,854 — Pirrung, Fodor, Read, et al.

• Title: "Large scale photolithographic solid phase synthesis of polypeptides and receptor binding screening thereof" (the VLSIPS™ patent)
• Cited in: expressly named and incorporated by reference in US 5,837,832's "Description of Related Art."
• Date: issued 1992‑09‑01 (from general knowledge; not re‑verified this session).
• Status vs. priority date: §102(b) art (issued before 1992‑06‑25).
• Brief description: Light‑directed, photolithographic synthesis of large arrays of polymers/oligomers at defined sites on a solid support, with receptor‑binding screening.
• Anticipation analysis: Anticipates the platform elements of claim 1 — immobilized probes at separate known sites on a solid support synthesized photolithographically — but it does not disclose the claimed content combination (a first set exactly complementary that completely spans a reference sequence plus three same‑position single‑base substitution sets). It would not anticipate claim 1, but it constrains any claim to the array‑format concept, and because it is incorporated by reference it is also part of the specification's admitted art.

4. WO 90/15070 (PCT) and WO 92/10092 (PCT)

• Cited in: named and incorporated by reference in the "Description of Related Art" alongside US 5,143,854 as VLSIPS™ disclosures.
• Dates: WO 90/15070 published ~1990; WO 92/10092 published ~1992‑06 (dates from general knowledge; not re‑verified this session).
• Status: Printed‑publication art; WO 90/15070 is §102(b) art, WO 92/10092 is near/at the §102(b) boundary depending on exact publication day.
• Brief description: Very large scale immobilized polymer/oligonucleotide synthesis — array fabrication and mask‑based combinatorial synthesis.
• Anticipation analysis: Same as US 5,143,854 — platform art, not anticipatory of the tiling probe‑set combination of claim 1.

5. WO 89/10977 and WO 89/11548 (PCT)

• Cited in: the "Description of Related Art," for the proposition that tethered oligonucleotide probe arrays on solid supports were known for detecting specific target sequences.
• Dates: published ~1989 (general knowledge; not re‑verified this session).
• Status: §102(b) printed‑publication art.
• Brief description: Immobilized oligonucleotide probe arrays for detecting complementary target sequences.
• Anticipation analysis: Establishes the general immobilized‑probe‑array concept; does not disclose the specific tiled matched/mismatched probe‑set architecture of claim 1. §102 support for the "immobilized array" preamble only.

6. WO 93/17126 (PCT)

• Cited in: the "Description of Related Art" (grouped with US 5,202,231 and US 5,002,867).
• Date: published 1993 (commonly reported 1993‑09‑02 — after the 1993‑06‑25 priority date).
• Status flag: If published 1993‑09‑02, it is not §102(a)/(b) art against the 1993‑06‑25 priority date unless it carries an earlier effective date under §102(e). Treat its exact publication date as unverified and worth checking before relying on it.
• Brief description: Sequencing‑by‑hybridization / large probe‑set proposals.
• Anticipation analysis: Same family of "SBH proposal" art; relevant to §103, unlikely to anticipate claim 1.

7. Related family documents (not "prior art," flagged to avoid confusion)

• WO 95/11995 (Affymax Technologies N.V., published 1995‑05‑04): the international counterpart; the WO 00/40758 search report lists US 5,837,832, US 5,861,242 and US 6,045,996 as family members of this document.
• Ser. No. 08/082,937 (filed 1993‑06‑25, abandoned) and Ser. No. 08/143,312 (filed 1993‑10‑26): the parent applications — same‑family, not §102 art.

C. Bottom line on anticipation

On the evidence I retrieved, none of the cited references anticipates independent claim 1. Each of the strongest candidates covers only part of claim 1:

The claimed novelty — a spanning exactly‑complementary set plus three position‑matched substitution sets in a 100–100,000‑element, 9–20‑mer array — is not met by any single reference above. These are therefore best read as §103 combination art and as §102 art against narrower/dependent claims (e.g., the specific CFTR/mito/p53 probe sequences in claims 6–13, where a sequence‑specific reference could anticipate the probe but not the array claim as a whole).

D. What I could not verify (stated so you don't over‑rely)

1. The complete front‑page "References Cited" list for 5837832. I confirmed US 5,002,867 via Espacenet and the five PCT/patent items via the patent's own text, but I did not retrieve the full enumerated U.S.‑patent‑documents table (e.g., I could not confirm whether 5,324,633, 5,424,186, or 5,445,934 appear on the 832 front page). Do not treat Section B as exhaustive.
2. Exact issue/publication dates for US 5,202,231, US 5,143,854, WO 90/15070, WO 92/10092, WO 89/10977, WO 89/11548, WO 93/17126 — these are from general knowledge, not confirmed this session; verify each before filing any §102 chart.
3. Any non‑patent‑literature citations on the front page (e.g., Anderson et al. 1981, Nature 290:457‑465, which the specification cites for the mitochondrial reference sequence) — I did not retrieve the NPL list.

If you can supply the front‑page "References Cited" image or the USPTO Patent Center PDF, I will re‑run this as a full row‑by‑row anticipation chart with verified dates.

I'll verify the prior art references cited in this patent before building the § 103 analysis. Note one internal inconsistency up front: this task header says "Current Date: April 26, 2026," while the system context and the previously generated sections use 2026‑09‑30. I'll proceed with the analysis and flag it where a date matters.

Good — the searches confirmed several key prior-art characterizations and surfaced one important discrepancy I need to flag. Let me verify a few more references.

Obviousness Analysis — US 5,837,832 under 35 U.S.C. § 103

Scope and method. Consistent with the earlier sections, I treat the full patent text you supplied as authoritative and build on them (one independent claim — claim 1 — with claims 2–18 depending from it). For "prior art," I used the references identified in the patent's own Description of Related Art and the references it cites/incorporates, because I could not retrieve a rendered "References Cited" table from the Google Patents page in this session. Two verification notes up front:

• Discrepancy flagged: The patent's background cites "PCT patent publication No. WO 93/17126" alongside U.S. Pat. Nos. 5,202,231 and 5,002,867 as proposals using "large numbers of oligonucleotide probes." Live searches consistently identify WO 93/17126 as Chetverin ("sectioned, binary oligonucleotide arrays"; see https://www.freepatentsonline.com/y2014/0134621.html and https://patents.justia.com/patent/20110039728). I do not auto-correct; I note that WO 93/17126 is not the Southern publication (Southern's is WO 89/10977). If you were working from an assumption that WO 93/17126 = Southern, that assumption is contradicted by the search results.
• Date inconsistency flagged (again): the task header says April 26, 2026, while the system context and prior sections say 2026‑09‑30. It does not change this analysis, but the §102(b) calculus below is date-sensitive.

1. The governing standard

Under Graham v. John Deere Co., 383 U.S. 1 (1966), and KSR Int'l Co. v. Teleflex Inc., 550 U.S. 398 (2007), the question is whether the claimed subject matter as a whole would have been obvious to a person of ordinary skill at the time of invention. For a product/array claim like claim 1, obviousness can be shown by prior art that teaches the structure, even if the art did not appreciate every advantage of that structure (KSR; In re Kubin, 561 F.3d 1351 (Fed. Cir. 2009) — predictable results in the life sciences are not patentably distinct). A numerical range (100–100,000 probes; 9–20 nt; 12–17 nt) is ordinarily an obvious optimization when the results are predictable (In re Aller, 220 F.2d 454 (CCPA 1955)).

2. Prior-art inventory (all from the patent's own record)

The auto-generated "Prior art keywords" on the Google Patents page (seq, probes, probe, dna, sequence) is a keyword extraction, not evidentiary art.

3. Element mapping of claim 1

Claim 1 (per the earlier section): a solid-support array of 100–100,000 different 9–20‑mer probes at separate known sites, comprising (i) a first set exactly complementary to a reference sequence and completely spanning it with overlapping probes, and (ii) three additional sets identical to the first set except that one nucleotide — at the same position in all three sets — is a different nucleotide in each set.

Every element of claim 1 is individually present or inherently present in the cited art. The only arguable point of novelty is the packaging: a reference-specific "minimal set" instead of the complete n‑mer array. But the patent itself concedes that packaging is a mere design choice — "there are advantages … to using a minimal set of oligonucleotides specific to the sequence of interest, rather than a set of all possible N‑mers."

4. The three strongest § 103 grounds

Ground 1 — '854 (VLSIPS chip) + Strezoska 1991 + Southern. This is the most damaging combination. '854 supplies the enabled fabrication technology for high-density arrays on a solid support at known sites with linker attachment. Strezoska supplies the architecture: overlapping probes that span a known sequence plus mismatch variants used to discriminate sequence differences. Southern 1992 supplies the application to point-mutation detection in genomic DNA on an immobilized oligo array. Motivation: the field's express objective was fast, gel-free resequencing and mutation screening; a POSA would combine a proven array-fabrication platform with a proven probe-design strategy to reduce it to a chip. Result predictable: a perfect-match duplex exceeds a single-mismatch duplex in stability — a well-understood thermodynamic fact.

Ground 2 — Drmanac '231 + Fodor '854. Drmanac teaches SBH with large probe sets, including the complete n‑mer set. A complete set of 8‑mers (65,536) or a reference-specific subset within 100–100,000 probes inherently contains the "first set + three additional sets" recited in claim 1. Fodor '854 makes such an array physically realizable on a chip. Motivation: automating/reducing SBH reactions ("tens of thousands of hybridization reactions must be performed" in filter format). This ground borders on § 102 anticipation for a reference-specific single-position-substitution subset.

Ground 3 — Macevicz '867 + '854 + Southern. Macevicz most closely recites the interrogation logic: determine sequence by hybridizing against probe sets "having an invariant nucleotide at one position and a variant nucleotide at another position." Combined with an addressed array and the mutation-detection objective, the four-set architecture follows directly.

5. Dependent claims

• 2 (fourth set identical to the first) — inherent in the all-n‑mer approach; the specification calls it mere redundancy.
• 3 (both strands) — routine; the specification itself notes the second strand resolves secondary-structure gaps.
• 4–5 (12–17 nt; 15‑mers; position 7; 3′ attachment) — routine optimization; the art used octamers through 11‑mers (Strezoska; Drmanac 1993), and the middle-of-probe interrogation position is dictated by known mismatch-destabilization profiles.
• 6–13 (CFTR exon 10; mtDNA D‑loop 16280–356; p53 exon 6 ≥60 nt; exon 5 17‑mers) — these recite application to known genes. The reference sequences were published (Riordan et al. 1989 for CFTR; Anderson et al. 1981 for mtDNA, cited and incorporated; Buchman et al. 1988 for p53 exon 5). Once the reference sequence is known, the complementary probes are dictated by the sequence itself — obvious. The sequence-specific sub-claims (7, 8, 10, 12) carry the caveat in § 6.
• 14–15 (oligodeoxyribonucleotides; 10,000–100,000) — species/routine format choice.
• 16–17 (HIV reverse transcriptase) — application of the same architecture; the patent concedes the RT mutations were known.
• 18 (linker) — expressly taught by VLSIPS linker chemistry ('854).

6. Counterarguments the patentee would raise, and my assessment

1. "Failure of others / non-enabling prior art." The specification states that '231, '867 and WO 93/17126 "proposed the use of large numbers of oligonucleotide probes … but failed to provide an enabling method." Under § 103, a reference must be enabling to serve as art. Assessment: this is the patentee's best rebuttal, but it is unsupported by any showing of what was missing; the Strezoska 1991 experimental paper and Southern 1992 experimental work are enabling, working examples of the key elements. The statement also cuts against the patentee's own novelty story, since these are the very references the examiner would have had.
2. Unexpected results. The patent reports non-uniform discrimination (FIG. 16: base identity mattered more than mismatch position) and ~95% read accuracy, with some probes failing to hybridize. Assessment: these results were largely predictable in direction; they tend to undercut, not support, a robust unexpected-results showing. A POSA expects GC content and mismatch identity to affect Tm.
3. Long-felt need. SBH had been proposed since 1987–1988 (Bains & Smith; Drmanac/Crkvenjakov). A long-felt, recognized need whose solution is the claimed design supports obviousness (KSR), though the patentee may argue it rebuts.

Date caveats that could change the picture: (a) Drmanac 1993 Science (1993‑06‑11) predates the 1993‑06‑25 priority date by ~2 weeks but would be §102(a)/§103 art only if the invention date is later — a swearing-behind issue. (b) WO 93/17126 published 1993‑09‑02, after the 1993‑06‑25 priority date; it qualifies as art only if the claims are not entitled to that date (its §102(b) force depends on which filing date governs). (c) The earlier section's priority-Chain point (§ 120 dates) is critical here: if claims get the 1993‑06‑25 date, some references shift from §102(b) to §102(a)/§103 status.

7. Bottom line

On the record cited by the patent itself, claim 1 is very likely obvious under § 103 over (i) Strezoska 1991 + US 5,143,854 + Southern 1992, and independently over (ii) US 5,202,231 + US 5,143,854, with US 5,002,867 supplying the invariant/variant interrogation logic. The dependent claims are, with one narrow exception, obvious as applications to known sequences or routine optimizations. The one genuine battleground is the §102(b)/§103 date status of WO 93/17126 and Drmanac 1993 Science, which turns on whether the claims are entitled to the 1993‑06‑25 priority date — I cannot resolve that from the sources available here, and it is the question I would verify first against the official file history.

Confidence and what I could not verify: I could not retrieve the printed "References Cited" table from the Google Patents page, the full text of WO 90/15070/WO 92/10092, or the official issue date of US 5,143,854 in this session (my searches hit a step limit). Treat the WO 93/17126 = Chetverin identification as a search result, and the '854/WO 90/15070 dates as high-confidence but not re-verified here. As in the earlier sections, I found no 2026 CAFC activity, but I could not run a native docket query, so treat that as a search-based negative, not a certification. Also note the earlier-flagged printing error: the patent's figure legends call the SEQ ID NOS. "peptide sequences" when they are nucleic acid sequences — any SEQ-ID-based claim construction (claims 7, 8, 10, 12) should account for that and should be checked against the official sequence listing.