US 5807522

I'll search for information on US Patent 5,807,522 and any CAFC 2026 docket activity.

Both searches returned empty results. Let me try broader and alternate queries.

Let me search specifically for litigation and CAFC docket activity involving this patent.

Based on the authoritative full patent text provided and the web searches performed, here is my summary. I was unable to locate any CAFC 2026 docket entries for this specific patent, so I flag that item as unconfirmed.

Summary of US Patent 5,807,522 (US5807522A)

• Title: Methods for fabricating microarrays of biological samples
• Patent / Application No.: US5807522A / US08/477,809
• Assignee: Leland Stanford Junior University — more precisely, per the Sept. 18, 1995 recorded assignment, The Board of Trustees of the Leland Stanford Junior University (Palo Alto, CA). (A Nov. 17, 2008 recorded assignment to NIH/U.S. Government is an "Executive Order 9424, Confirmatory License," not a transfer of ownership.)
• Inventors: Patrick O. Brown and Tidhar Dari Shalon
• Filing date: June 7, 1995 (a continuation-in-part of abandoned application Ser. No. 08/261,388, filed June 17, 1994; the effective priority date is June 17, 1994)
• Issue date: September 15, 1998
• Legal status: Expired – Lifetime (anticipated expiration September 15, 2015)
• Abstract (verbatim): "A method and apparatus for forming microarrays of biological samples on a support are disclosed. The method involves dispensing a known volume of a reagent at each selected array position, by tapping a capillary dispenser on the support under conditions effective to draw a defined volume of liquid onto the support. The apparatus is designed to produce a microarray of such regions in an automated fashion."

Independent claim (claim 1 — plain-language overview)

Claim 1 is the sole independent claim (claims 2–7 are dependent). It is directed to a method of forming a microarray of discrete analyte-assay regions on a solid support, where each region carries a selected, analyte-specific reagent. The method has three basic elements:

1. Loading: an aqueous solution of a selected analyte-specific reagent is loaded into a reagent-dispensing device having an elongate capillary channel that holds the solution and has a tip region where the solution forms a meniscus;
2. Tapping/depositing: the tip is tapped against the solid support at a defined surface position with an impulse sufficient to break the meniscus in the capillary channel, depositing a selected volume of between 0.002 and 2 nl (2 picoliters to 2 nanoliters) of solution on the surface; and
3. Repeating: steps (a) and (b) are repeated until the desired microarray is formed.

In essence, claim 1 covers the "tap-print" method: using an open capillary dispenser whose liquid meniscus is broken by mechanical tapping contact with the substrate to deposit a precisely controlled picoliter-to-nanoliter droplet at each array position, repeated to build a microarray.

Dependent claims (plain-language overview)

• Claim 2: The reagents forming the discrete regions are distinct nucleic acid strands, and the steps are repeated until the microarray has about 100 or more distinct nucleic-acid regions per cm².
• Claim 3: Same as claim 2, but at a higher density of about 1,000 or more distinct nucleic-acid regions per cm².
• Claim 4: The method of claim 2, wherein the capillary channel is open-sided.
• Claim 5: The method of claim 3, wherein the capillary channel is open-sided.
• Claim 6: The method of claim 4, wherein the deposited volume is between 0.002 and 0.25 nl.
• Claim 7: The method of claim 5, wherein the deposited volume is between 0.002 and 0.25 nl.

Litigation / CAFC 2026 docket search

• Google Patents flags that the patent family (ID 26948575) has litigation history (Darts-ip link provided). Historical reporting (e.g., Science, 1999) describes infringement litigation in U.S. district court (Delaware/San Francisco) from the late 1990s–2000 involving Affymetrix and Incyte — Incyte Pharmaceuticals being the exclusive licensee of the '522 patent — plus related settlement announcements involving the '522 patent's licensees. I did not independently verify those docket details beyond the secondary sources.
• I could not find any CAFC 2026 docket entries specific to patent 5807522. My searches of USPTO/CAFC 2026 records returned no matching docket or appeal for this exact patent number. Given the patent reached its anticipated expiration on September 15, 2015, active CAFC 2026 litigation on the '522 patent itself appears unlikely, but I state this as unconfirmed rather than definitive — I had no authoritative source locating a 2026 CAFC proceeding for this patent.

Notes on uncertainty

• The full specification, figures, and claims above come from the Google Patents text supplied in the prompt (authoritative). Web search results corroborated the bibliographic data (title, inventors "Brown et al.," issue date September 15, 1998, Stanford assignment, and family members such as EP0804731, EP0913485, US6110426, US7323298, US7378236, US7442499, US7615368).
• I found no USPTO or CAFC record contradicting the bibliographic data.
• One minor discrepancy in secondary sources: a Science article states the patent was "received... in 1999," but the USPTO/Google record clearly shows an issue date of September 15, 1998; I treat the 1998 issue date as authoritative.

Known litigation involving U.S. Patent No. 5,807,522

Based on the searches I was able to run, there is at least one confirmed U.S. district court action in which US 5,807,522 was asserted. Details below.

1. Incyte Genomics, Inc., et al. v. Invitrogen Corporation

• Case No.: 3:01-cv-02141
• Jurisdiction: U.S. District Court for the Southern District of California
• Plaintiff(s): Incyte Genomics, Inc. (and related entities, per the case caption "Incyte Genomics Inc, et al.")
• Defendant(s): Invitrogen Corporation
• Filing date: November 21, 2001 (complaint amended December 21, 2001, and March 7, 2002)
• Patents-in-suit: Sixteen patents, including US 5,807,522 and US 6,110,426, which Incyte's SEC disclosures described as patents "relat[ing] to methods of fabricating microarrays of biological samples." (The other asserted patents were gene patents and RNA-amplification/gene-expression patents.)
• Relief sought: Injunction, damages, treble damages for alleged willful infringement, fees, costs, and interest.
• Outcome/status: Not verifiable from the sources retrieved. I could not confirm a final judgment, settlement, or dismissal for this specific case. Context from Incyte's contemporaneous 10-K filings indicates that Incyte was exiting the microarray products/services business during 2001 and in December 2001 settled separate microarray-related litigation with Affymetrix, Inc.; however, I found no reliable record of the ultimate disposition of the Invitrogen S.D. Cal. case.

Source: Stanford NPE Litigation Database (https://npe.law.stanford.edu/patent/5807522), which lists: "1 | Incyte Genomics Inc, et al v. Invitrogen Corp | 3:01-cv-02141 | S.D.Cal."; Incyte SEC filing of Nov. 21, 2001 (https://investor.incyte.com/node/9266/html).

Related actions in the same dispute (also reported by Incyte, Nov. 21, 2001)

The same Incyte SEC filing describes satellite litigation tied to this dispute, though it does not unambiguously confirm which patents were asserted in each:

• Invitrogen Corporation v. Incyte Genomics, Inc. – U.S. District Court for the District of Delaware. Incyte filed its Answer and seven counterclaims on November 21, 2001, and moved to transfer the action to the District of Maryland, where Incyte said Invitrogen was already a party to three infringement actions involving "the same patents-in-suit." The patents Invitrogen asserted in Delaware are not identified in the filing I retrieved, so I cannot confirm US 5,807,522 was at issue there.
• Three (unidentified) infringement actions in the District of Maryland – referenced in the same filing as involving Invitrogen and "the same patents-in-suit"; case numbers, captions, and the specific patents asserted were not identified in the retrieved source.

I was unable to retrieve the Darts-IP litigation-family page referenced on Google Patents (which flags the US 5,807,522 family as having litigation) to obtain a complete case list, and I could not verify any additional cases (e.g., any involving Synteni, Incyte, or Affymetrix asserting or challenging this patent specifically).

Caveats

• I did not find any case where US 5,807,522 was asserted by Stanford University itself; the confirmed assertion was by Incyte Genomics as exclusive licensee.
• The search hit limit prevented me from checking PACER, Unified Patents, or Darts-IP directly for a comprehensive list, so there may be additional district-court or ITC matters involving this patent that I could not confirm. If you want, I can continue with targeted PACER/Unified Patents searches in a follow-up.

Proceedings overview

The USPTO Open Data Portal (ODP) record for US Patent 5,807,522 shows zero AIA trial proceedings (IPR/PGR/CBM), and independent web searches (USPTO PTAB, PTACTS, Google Patents, and general queries combining the patent number with "inter partes review," "final written decision," "Patent Trial and Appeal Board," and IPR-year petition numbers) returned no filed petition, no institution decision, and no Final Written Decision against this patent. There are no active proceedings, no claims invalidated, and no claims sustained through IPR. The defensive bottom line for a defendant: the patent has never been tested in an AIA trial — but it expired on 2015-09-15 (status: "Expired – Lifetime"), so the substantive patent-enforcement threat is already extinguished by lapse of term, and PTAB practice adds nothing further.

Proceedings detail

(None on file)

• Type: N/A
• Filed: N/A
• Status: No AIA trial proceeding exists. The structured "PTAB proceedings on file" block reports: "The USPTO ODP API returns no AIA trial proceedings for this patent as of the most recent ingest." Web searches did not surface any older or recently filed IPR/PGR/CBM that ODP had not yet indexed — searches for IPR2023/IPR2024/IPR2025/CBM/PGR numbers tied to "US5807522" returned no results.
• Judge panel: N/A
• Petition grounds: N/A
• Institution decision: N/A
• Final Written Decision: None issued. I did not fabricate claim-level dispositions — no FWD exists for this patent.
• Settlement / termination: N/A. The patent's "Expired – Lifetime" legal status reflects passage of time (35 U.S.C. § 154(c) term; anticipated expiration 2015-09-15), not a PTAB termination.
• Appeal: None.
• Defensive value: Zero AIA-trial precedent exists to cite. For someone facing assertion today, the dispositive fact is not PTAB history but patent expiration — any demand premised on post-expiration activity in the U.S. is legally baseless (35 U.S.C. § 154; no damages accrue after expiration).

Strategic summary

Claim status. Because no IPR/PGR/CBM was ever filed, no claim of 5,807,522 has been canceled or sustained by the PTAB — all seven claims (independent claim 1 and dependent claims 2–7) are "untested" in the AIA-trial sense. The only claim-status event in the record is legal expiry of the entire patent on 2015-09-15, which renders the claims unenforceable for future conduct regardless of validity. Note also that the patent's own priority chain (filed 1995-06-07, priority 1994-06-17) long predates the AIA; the relevant historical enforcement was district-court litigation in the late 1990s–2000s era (family litigation flagged on Google Patents, associated with the Stanford/Incyte microarray licensing disputes) — all pre-AIA and outside PTAB jurisdiction.

Estoppel landscape (§ 315(e)(2)). With no IPR ever instituted, no § 315(e)(2) estoppel attaches to anyone. No petitioner exists, so no defendant, real party in interest, or privy is barred from raising any prior-art ground. If, hypothetically, validity were ever litigated (e.g., as a defense to a pre-expiration damages claim — the only remnant exposure), a defendant would have the full universe of § 102/§ 103 art available, including art that postdates the 1994 priority date and all art that would have been available in the 1990s litigation. Estoppel is a non-issue here.

Pattern signals. There is no pattern of serial IPRs, no defensive-aggregator involvement (Unified Patents or otherwise), and no aggressive PTAB practice by the patent owner (The Board of Trustees of the Leland Stanford Junior University; the 2008 NIH assignment is only an Executive Order 9424 confirmatory license). The absence of PTAB activity is unsurprising and itself informative: the patent expired in 2015, and AIA trial practice (post-2012) largely post-dated the patent's most commercially valuable enforcement window, which was already tied up in district court years earlier. Well-asserted, in-force patents attract IPRs; expired ones do not — and this one's lifecycle (issued 1998, litigated pre-AIA, expired 2015) never overlapped meaningfully with the IPR regime.

Recommended next steps

• Confirm the expiration defense first. Before spending a dollar on prior art, verify the term: US 5,807,522 issued 1998-09-15 from an application filed 1995-06-07 (pre-GATT/URAA transition rules apply via the 1994-06-17 priority application), with anticipated expiration recorded as 2015-09-15. If the accused activity is after that date, the answer to any demand is lack of infringement of an expired patent — no validity analysis needed. The USPTO assignment record and Google Patents legal-status page document the "Expired – Lifetime" status.
• If the demand reaches pre-expiration conduct, there is no PTAB FWD to cite (I confirmed none exists — do not represent otherwise to opposing counsel or the Board). The correct forum analysis is: IPR is time-barred/pointless against an expired patent for post-expiration conduct, and any pre-expiration damages theory must be answered in district court with the full, unrestricted prior-art toolkit (no § 315(e)(2) estoppel exists).
• PTAB E2E check for diligence. The ODP canonical list shows no proceedings, and my searches corroborated that. If you want an independent confirmation record, run the patent number in the USPTO PTAB Trial Search (PTAB E2E) and the Patent Center/PRPS file wrapper for 08/477,809 before making any representation to a tribunal — but the expected result is a null return.
• Watch the related family, not the '522 itself. If the assertion campaign cites continuation/continuation-in-part family members (e.g., US 6,110,426, US 7,378,236, US 7,323,298, US 7,442,499, US 7,615,368, US 7,625,697), those have their own separate PTAB and expiration profiles. The '522's clean PTAB record says nothing about whether an IPR on a still-in-force family member is viable — run the same ODP check per patent number.

Sources: USPTO ODP structured data (no AIA proceedings on file — canonical); Google Patents record for US5807522A (bibliographic data, status "Expired – Lifetime," anticipated expiration 2015-09-15, family/litigation flag, assignment history); web searches of USPTO/PTACTS/Google Patents and general queries returned no PTAB proceeding tied to this patent number. No PTAB Final Written Decision or CAFC appeal exists to link because none was filed.

I'll research the assignment record for US 5,807,522 using the USPTO Assignment Center and cross-referencing sources. Let me run several targeted searches.

Let me dig deeper into the assignment records and the entities involved.

Assignment Chain Reconstruction — US 5,807,522

Important methodological caveat up front (do not skip): I was unable to retrieve the USPTO Assignment Center detail pages for this patent within the available search budget — every query hitting assignment.uspto.gov, assignmentcenter.uspto.gov, and uspto.report returned either no useful results or was blocked. I therefore could not obtain reel/frame numbers, the recordation documents, or the correspondent-of-record fields. The assignment facts below are taken from the Google Patents "Legal Events" record supplied in the authoritative patent text (which lists the same recordation events the Assignment Center would surface, but without reel/frame or correspondent detail). I have not fabricated reel/frame numbers or correspondent names. Where a field is unknown, I say so. If you need the reel/frame and correspondent fields — which are the crux of the repeat-correspondent signal — this must be pulled directly from the Assignment Center PDFs by a human or a session with direct database access.

Inventors

• Employer determination confidence: Moderate. Brown's Stanford/HHMI affiliation and Shalon's Stanford graduate-work history are well established in the secondary literature and patent family record, but the specification itself does not state employment. Treat title-level detail as unverified.
• Unusual-pattern check — "all inventors departing within 12 months of filing" (a pre-fire-sale tell): Not present / not clearly indicated. One co-inventor (Shalon) moved from academia into a startup (Synteni) around the filing window, but the other (Brown) stayed at Stanford. This is the ordinary academic-inventor spin-out pattern, not a mass exodus preceding a portfolio fire-sale. I could not pin Shalon's exact departure date with confidence.
• Cross-reference flagged in prior sections: The previously generated litigation summary identifies Incyte Genomics as exclusive licensee asserting the patent — consistent with the Synteni→Incyte corporate path (Incyte acquired Synteni in 1998). No contradiction with the chain below.

Original assignee

• Entity named on the issued patent: The Board of Trustees of the Leland Stanford Junior University (Palo Alto, California).
• Primary line of business: Private research university (education and sponsored research). It is a non-practicing institution with respect to this technology.
• Did it ship a product embodying the claims? No. Stanford is an academic institution; it does not market a microarray product. The technology was licensed (not assigned) for commercialization — consistent with the previously generated sections identifying Incyte Genomics as exclusive licensee. Licensing, not product sales, is Stanford's commercialization model here. Note the specification itself recites federal funding: "Grant No. HG00450 awarded by the National Institutes of Health."
• Current status: Operating (active university). No bankruptcy, dissolution, or acquisition of the assignee.

Assignment timeline

Reel/frame and correspondent fields could not be retrieved (see caveat above). Every entry below is sourced from the Google Patents legal-events record, which omits both. No assignment other than the two below appears in the record.

• ~1995-06-07 / recorded 1995-09-18 — Reel/Frame not retrieved

  • Conveyance: Assignment of Assignors Interest (Google Patents text: "ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS)")
  • Assignor: Patrick O. Brown; Tidhar Dari Shalon
  • Assignee: The Board of Trustees of the Leland Stanford Junior University
  • Correspondent: Not retrieved — flag as unknown; a repeat-correspondent analysis cannot be run without it.
  • Context: Original inventor-to-employer assignment (university employment obligation); recorded shortly after the 1995-06-07 filing of application 08/477,809.

• 2008-11-17 (date as recorded) — Reel/Frame not retrieved

  • Conveyance: Executive Order 9424, Confirmatory License (not an ownership transfer)
  • Assignor: Stanford University
  • Assignee: National Institutes of Health (NIH), U.S. Dept. of Health and Human Services (DHHS), U.S. Government
  • Correspondent: Not retrieved.
  • Context: Government confirmatory license — confirms federal march-in/retained rights under the Bayh-Dole framework flowing from NIH Grant HG00450. This is a rights record, not a change of ownership; title did not leave Stanford.

Finding: There is no recorded post-issuance ownership transfer of US 5,807,522. The chain begins and ends with The Board of Trustees of the Leland Stanford Junior University; the only other recorded instrument is the 2008 NIH confirmatory license. No LLC, no asserter, no aggregator ever appears as assignee.

Timeline diagram

timeline
    title Ownership of US 5807522
    1994 : Priority application filed
    1995 : Application filed
         : Assigned to Stanford Board of Trustees
    1998 : Patent issued
    2001 : Incyte sues Invitrogen as licensee
    2008 : NIH confirmatory license recorded
    2015 : Patent expired

NPE / troll-pattern signals

1. Shell-entity transfer — Not present. No assignment to any "IP / Patents / Licensing / Holdings / Ventures" LLC is recorded. The only recorded assignee is Stanford (a university), and its sole other instrument (2008-11-17) is a confirmatory license to a federal agency, not a shell transfer.

2. Known asserter in the chain — Not present as an assignee. Neither Stanford nor NIH/US Government is on any NPE list (Acacia, Marathon, IV, IPNav, Wi-LAN, Conversant, etc.). Caveat / adjacent finding: the patent was asserted by Incyte Genomics as exclusive licensee (Incyte Genomics v. Invitrogen, 3:01-cv-02141, S.D. Cal., per the previously generated litigation section) — but Incyte never appears as a recorded assignee, so this is a licensee-assertion, not an NPE title transfer. Incyte (a former genomics operating company) is not on the classic high-frequency-plaintiff lists.

3. Repeat correspondent across the chain — Unclear. This is precisely the signal I could not test, because the corroborating field (correspondent of record) could not be pulled. Recurrence cannot be assessed with one or zero data points. Do not treat this as "not present" — treat it as unverified.

4. Cascading transfers (multiple chained LLCs in <24 months) — Not present. Only one ownership assignment exists, dated 1995. No chain, no clustering.

5. Pre-litigation transfer (assignment within 6 months before first suit) — Not present. The first suit identified (2001-11-21) is ~6 years after the last ownership assignment (1995) and predates the 2008 license by 7 years. No assignment accompanies the assertion.

6. Bankruptcy fire-sale — Not present. No Chapter 7/11 sale, no transfer out of a distressed operating company.

7. Privateering — Not clearly present. A university (non-practicing) licensed the technology to a company that later asserted it — superficially resembling privateering — but the classic privateering tell (an operating company assigning to an NPE to assert on its behalf) is absent: Stanford retained title; the assertion ran through an exclusive license, and Incyte was itself an operating genomics business, not a pure assertion vehicle.

8. Defensive aggregator (anti-NPE) — Not present. The chain does not terminate at RPX, AST, LOT, Unified Patents, or OIN. The 2008 NIH record is a government rights confirmation, not a defensive aggregation. (Note: this is not the same as "neutralized" — the patent simply expired at term.)

Verdict

Insufficient data — the chain contains only the original assignment (Brown & Shalon → Board of Trustees of Leland Stanford Junior University, recorded 1995-09-18) plus a non-ownership government confirmatory license (Stanford → NIH/DHHS, recorded 2008-11-17). The assignee never changed; no LLC, asserter, or aggregator ever held title, and thus no shell-transfer, cascading-transfer, pre-litigation-transfer, or fire-sale signal can be supported. The one signal that could matter — a repeat correspondent — could not be evaluated because the Assignment Center reel/frame and correspondent fields were not retrievable in this session, so I decline to score it either way rather than infer from naming. The single notable fact is licensee-based assertion: Incyte Genomics asserted the '522 as exclusive licensee against Invitrogen (3:01-cv-02141, S.D. Cal., 2001) — an operating-company licensee suing a competitor, which is not an NPE title-transfer pattern.

To move this from Insufficient data to a scoreable verdict, retrieve from the Assignment Center: (i) the reel/frame for the 1995-09-18 and 2008-11-17 records, and (ii) the correspondent of record on each, then compare those names across the family (US 6,110,426; 7,378,236; 7,323,298; 7,442,499; 7,615,368; 7,625,697).

Verify at: https://assignment.uspto.gov/patent/index.html (or https://assignmentcenter.uspto.gov/) — search by patent number 5807522 or application 08/477,809.

I'll research the prior art cited on the face of US 5,807,522. Let me run several targeted searches.

Let me try to retrieve the front-page "Patent Citations" (prior art) list specifically.

The front-page "References Cited" list isn't appearing in search snippets. Let me try more specific retrieval paths.

Prior-Art Analysis — U.S. Patent No. 5,807,522

Current date: April 26, 2026. 5807522 is interpreted literally as US 5,807,522 (application US08/477,809), "Methods for fabricating microarrays of biological samples," Brown & Shalon, filed 1995‑06‑07, priority 1994‑06‑17, issued 1998‑09‑15, expired 2015‑09‑15. I excluded all near‑number hits (see §4).

1. Important scoping caveat — what "each patent citation" actually consists of here

I searched for the front‑page "References Cited" (backward/prior‑art citation) list of US 5,807,522 in the USPTO/Google Patents/Espacenet/FreePatentsOnline/Justia records. I could not retrieve that examiner/applicant citation list, and I will not fabricate it.

Critically, the authoritative full text supplied for this patent does not contain the front‑page "References Cited" block. It contains only two citation-like blocks, and neither is the prior-art patent list:

⚠️ Flag: The user's request implicitly assumes the fetched patent record includes the front‑page citation list. It does not. The 1,037 entries under "Cited By" (e.g., WO1999024822A1, WO1999031468A1, US6,110,426) are later documents citing '522 and post‑date its 1994 priority date; they are irrelevant as § 102 art against '522 itself. Treating them as "prior art" would be a category error. Likewise, EP 2311855 A3's search report citing "US 5807522 A … [XD]" is '522 being used as prior art against a different application — not prior art against '522.

So my analysis below is grounded in the prior art that the specification itself identifies and discusses (which is the substance a § 102 inquiry would focus on for an expired patent). If you need the literal examiner citation list, it must be pulled from the USPTO Patent Center file wrapper for 08/477,809 or the printed front page — I was unable to retrieve it within this session.

2. Prior art identified in the authoritative text

2.1 Patent reference

US 5,143,854 — Pirrung et al. (1992) ("Large scale photolithographic solid phase synthesis of polypeptides and receptor binding screening thereof")

• Cited in: specification's References list; also discussed in Background.
• Description: Light‑directed, step‑wise in situ synthesis of polymers at discrete regions of a support; array elements built by photolithographic masking, not by dispensing droplets.
• Potential § 102 relevance: Claim 3 / claim 5 (≥ ~1,000 discrete nucleic‑acid regions/cm²). Fodor/Pirrung arrays achieve densities at or above this range. But because claims 3 and 5 depend from claim 1, the claim‑1 method limitations (capillary‑channel dispenser, meniscus‑breaking tap) still control — Pirrung's synthesis method does not anticipate claim 1.

2.2 Non‑patent literature cited in the specification

Fodor et al., Science 251:767–773 (1991) — light‑directed synthesis of high‑density arrays. Same analysis as Pirrung: density‑relevant to claims 3/5, method‑inapposite to claim 1.

Khrapko et al., DNA Sequence 1:375–388 (1991) — oligonucleotide matrix made by manually spotting DNA onto a thin polyacrylamide layer with a micropipette. This is the closest "spotting to form an array" art. Does not anticipate claim 1: no elongate capillary channel dispenser, no meniscus‑breaking tap impulse, no 0.002–2 nl controlled volume (manual micropipette = microliter scale, variable).

Lehrach et al., "Hybridization fingerprinting…," Genome Analysis Vol. 1, pp. 39–81 (1990) — pins dipped into 96‑well plates transfer samples to a membrane; 9,216 spots in 22 × 22 cm (~19 regions/cm²). Does not anticipate claim 1 (no capillary channel, no meniscus break, highly variable volume — the specification expressly criticizes this). Notably it is below the 100/cm² threshold of claim 2, so it also fails to reach the dependent density claims.

Southern et al., Genomics 13:1008–1017 (1992) — analyzing sequence by hybridization to oligonucleotide arrays; "a related method" per Background. Does not anticipate claim 1 (array formation by in‑situ/derivatized synthesis, not droplet dispensing by tapping).

Abouzied et al., J. AOAC Int'l 77(2):495–500 (1994) — printing horizontal lines of antibodies on nitrocellulose, separating regions with vertical hydrophobic stripes; ELISA colorimetric readout. Relevant to the multicell/barrier substrate subject matter discussed in the specification (not to claims 1–7, which are all method‑of‑dispensing claims). Does not anticipate any of claims 1–7. ⚠️ Date note: a 1994 journal issue may post‑date the 1994‑06‑17 priority date, so its § 102 status is date‑sensitive.

Drmanac et al., Science 260:1649–1652 (1993) — sequencing by hybridization on arrays; background/contextual. Not anticipatory of the dispensing method.

Kuriyama et al., "An ISFET Biosensor," Applied Biosensors (1989) — sensor/MOSFET biosensor chapter; cited for detection context, not array fabrication.

Nelson et al., Nature Genetics 4:11–18 (1993); Riles et al., Genetics 134:81–150 (1993); Bohlander et al., Genomics 13:1322–1324 (1992); Schena et al., PNAS 89:3894–3898 (1992); Maniatis et al., Molecular Cloning (1989) — these are methodology/utilization references used to enable the Examples (yeast mapping, PCR amplification, cloning, gene‑expression protocol), not anticipatory array‑fabrication art for claim 1.

2.3 Additional prior art discussed (not formally listed) in the Background

• "Dot‑blot" / "slot‑blot" vacuum‑manifold methods — transfer ~96 aqueous DNA samples (≈3 mm wells) from wells to porous membrane; volumes in the microliter range. Anticipates? No — no capillary‑channel tapper, no 0.002–2 nl volume, and the specification notes it is limited to ~96 samples/array and is manual.
• QA Life Sciences gridded membrane (hydrophilic/hydrophobic grid on membrane) — Background states reagents can still flow between grids; substrate art, not claim 1.
• Pall Corp. 96‑well filter plate — porous filter heat‑sealed to plate bottom; cells hold one element each. Substrate art; not claim 1.
• Hyseq "array of arrays" — hydrophobic grid on a non‑porous support; substrate art; not claim 1.

3. Claim‑by‑claim § 102 bottom line

Assessment: On the art identified in the authoritative text, no single reference anticipates claim 1; the novelty appears to reside in the combination of (i) an open, elongate capillary‑channel dispenser whose liquid meniscus is broken by a mechanical tapping impulse against the support, and (ii) the resultant precisely controlled 0.002–2 nl deposited volume, repeated to build the array. The density‑based dependent claims (2, 3, 5) are the most exposed to Pirrung/Fodor‑type art, but because they depend from claim 1 the method limitations continue to govern.

4. Numbers excluded per your instruction (literal interpretation)

• US 5,807,552 — appears in an EveryPatent snippet describing "Methods for Fabricating Microarrays of Biological Substances, Brown, et al." This is a different patent number, and the description attached to it is inconsistent with '522's title ("samples," not "substances"). Per the strict rule I do not auto‑correct it; I simply flag that this citation, as written in that citing document, appears erroneous and is not US 5,807,522.
• US 6,110,426, US 7,378,236, US 7,323,298, US 7,442,499, US 7,615,368, US 7,625,697 — '522 family members, not prior art against '522.

5. Honest limitations

• I did not obtain the examiner/applicant front‑page References Cited list for US 5,807,522; the record supplied omits it and my retrieval attempts were cut off by a search‑step limit. Anything I would state as "the patents cited on the face of '522" beyond Pirrung US 5,143,854 would be unverified.
• The § 102 mapping above is therefore built from the references the specification itself cites/discusses, which is the defensible evidentiary basis available here. For a formal validity opinion, pull the file wrapper (USPTO Patent Center, application 08/477,809) and the printed front page.
• All § 102 analysis is pre‑AIA (priority 1994‑06‑17), and the patent is expired (2015‑09‑15), so the practical impact of any anticipation theory today is limited to pre‑expiration damages defenses.

Primary source: Google Patents record for US5807522A (authoritative text supplied), which mirrors the USPTO bibliographic record.

I'll ground this obviousness analysis in the prior-art references cited in the patent's own References/Background section, verifying their content where possible.

Obviousness Analysis — U.S. Patent No. 5,807,522 under 35 U.S.C. § 103

Technical patent analyst's assessment. Retrospective/hypothetical posture: the patent expired 2015‑09‑15 (status "Expired – Lifetime"), so no live validity contest exists. This analysis is framed as a validity opinion would be — i.e., what a challenger could have argued and what the patent owner could rebut.

I. Governing legal framework

• Statute: The application (Ser. No. 08/477,809) was filed 1995‑06‑07, with priority to 1994‑06‑17, so pre‑AIA § 103(a) applies. The inquiry is whether the differences between the claimed invention and the prior art are such that the subject matter as a whole would have been obvious at the time the invention was made to a person having ordinary skill in the art (PHOSITA).
• Graham v. John Deere factors: (1) scope and content of the prior art; (2) differences between prior art and claims; (3) level of ordinary skill; (4) secondary considerations (objective indicia).
• KSR Int'l v. Teleflex (2007) factors a challenger would invoke: known elements combined according to known methods; simple substitution of one known element for another; use of a known technique to improve similar devices in the same way; and "obvious to try" where the art identifies a finite number of predictable solutions.
• Admitted prior art: Every reference in the patent's REFERENCES section, plus the "currently available" methods described in the BACKGROUND, are the applicant's own characterization of the state of the art. These statements are usable as § 103 art and, crucially, as statements of the problem and of the deficiencies motivating modification.

II. Level of ordinary skill (1994)

A PHOSITA at the June 1994 priority date would be a molecular biologist or bioengineer (Ph.D. or M.S. plus several years) with working familiarity with: (a) dot/slot‑blot and pin‑based membrane arraying; (b) automated liquid handling and capillary/pipette dispensing; (c) solid‑phase nucleic‑acid hybridization and fluorescence/colorimetric detection; and (d) the then‑emerging "DNA chip"/sequencing‑by‑hybridization literature. This is a multidisciplinary artisan — molecular biology plus precision liquid‑dispensing mechanics — which matters because the strongest motivation arguments draw on the liquid‑handling arts.

III. The claims at issue, and where the art stands

US 5,807,522 has only seven claims, all method claims, and claim 1 is the sole independent claim. The practical consequence is that the entire claim set rises or falls on the claimed dispensing mechanics — the density (claims 2–3), channel‑geometry (claims 4–5), and volume (claims 6–7) limitations are all dependent and add nothing that can rescue claim 1 if it fails.

IV. Content of the cited prior art (verified)

Lehrach et al. 1990 (Genome Analysis, Vol. 1, 39–81). Pin‑based mechanical arraying: pins dipped into microtiter wells transfer genomic fragments to a membrane, using staggered pins to create 9,216 spots in a 22 × 22 cm area. Confirmed in the literature and in downstream patents quoting it (e.g., US 2011/0130306). The patent's own Background concedes the two operative deficiencies: "the volume of DNA spotted in each pixel of each array is highly variable" and "the number of arrays that can be made with each dipping is usually quite small."

Khrapko et al. 1991 (DNA Sequence 1:375–388). Individual 8‑mers immobilized as dots in a thin polyacrylamide gel fixed on a glass plate; explicitly contemplates "miniaturized matrices or sequencing chips" with oligonucleotides "immobilized within 100 × 100 micron dots disposed at 100 micron intervals," giving "sensitivity of at least 10 attomoles per dot." (PubMed 1768861) This is the single most important reference in the list: it discloses (i) deposition of nucleic acid dots onto a solid glass support, (ii) a density of ~10⁴ regions/cm², and (iii) sub‑nanoliter spot volumes (~0.25 nl for a 100 µm hemispherical dot, matching the specification's own Table 1).

Fodor et al. 1991 (Science 251:767–773) and Pirrung et al., U.S. Pat. No. 5,143,854 (1992). Light‑directed, spatially addressable synthesis: an array of 1,024 peptides in ten steps, assayed by epifluorescence microscopy. Establishes that high‑density, positionally addressable arrays of distinct biological molecules on a solid support were known and were the recognized direction of the field.

Southern et al. 1992 (Genomics 13:1008–1017). A related in‑situ synthesis/attachment approach to ordered oligonucleotide arrays.

Abouzied & Pestka 1994 (J. AOAC Int. 77(2):495–501). Monoclonal antibodies immobilized as multiple lines on nitrocellulose membrane strips and sectored into hydrophobic compartments to minimize reagent use, with colorimetric readout and computer‑assisted image analysis. (PubMed 8199485) This is the closest art to the patent's multi‑cell/grid‑barrier substrate and open‑face hybridization subject matter.

Drmanac et al. 1993 (Science 260:1649–1652); Nelson et al. 1993 (Nat. Genet. 4:11–18); Riles et al. 1993 (Genetics 134:81–150). Sequencing‑by‑hybridization, ordered clone arrays for physical mapping, and the yeast clone library used in the patent's own Example 1 — i.e., the applications that create the demand for high‑density arrays.

Also cited by the Background (non‑reference art): QA Life Sciences grid membrane, Pall 96‑well filter plate, Hyseq "array of arrays." These are admissions that gridded/partitioned supports and barrier‑separated reagent wells were already commercial realities.

V. Proposed § 103 grounds

Ground A — Lehrach + Khrapko: renders obvious a method of making a deposited nucleic‑acid microarray on glass at ≥1000/cm²

• Where each reference is weak: Lehrach produces high‑count arrays but with unacceptable volume variability, on porous membranes, limited replication; it is a contact‑transfer method. Khrapko produces miniaturized, high‑density arrays of deposited material on a rigid, non‑porous glass support at ~10⁴ spots/cm² with sub‑nanoliter volumes and attomole sensitivity.
• The combination: Use a liquid‑carrying deposition element (Khrapko) instead of solid pins (Lehrach) to spot pre‑made, long nucleic‑acid reagents onto a rigid support, iterating the spotting to build the microarray.
• Motivation (KSR "known technique to improve a similar device in the same way"): The Background itself frames the unmet need as arrays with "a large number of micro‑sized assay regions separated by a distance of 50–200 microns or less" and "a well‑defined amount … of analyte associated with each region." Lehrach identifies variable volume as the obstacle; Khrapko supplies deposited dots at 100 µm spacing on glass with ~10 attomoles/dot. A PHOSITA seeking to cure Lehrach's variability and to miniaturize would be led directly to Khrapko's deposition‑on‑glass approach.
• Reaches: claims 2 and 3 (≥100 and ≥1000 distinct nucleic‑acid regions/cm²) and the "glass slide + deposited polynucleotide array" subject matter. Does not reach claim 1's capillary‑channel/meniscus‑break limitation (Khrapko's micropipette is a closed tube; Lehrach's pins are solid — neither has an open elongate channel bearing a meniscus).

Ground B — Lehrach + Fodor/Pirrung (+ Southern): the microarray format and density are the predictable direction of the field

• Fodor/Pirrung teach that thousands of distinct biological moieties can be placed at addressable positions on one solid support and read optically, and Khrapko/Southern show miniaturization to 100 µm features.
• Motivation: The Background concedes the in‑situ synthesis route (Fodor, Pirrung, Southern) is "generally limited to relatively short nucleic acid sample, e.g., less than 20 bases." The patent's own stated purpose is arrays of longer biopolymers ("polynucleotides having lengths of at least about 50 bp"), which by definition cannot be made by in‑situ synthesis. A PHOSITA therefore had an express reason to pursue deposition of pre‑made long nucleic acids into a microarray rather than synthesis — i.e., to combine Fodor's array‑format goal with a Lehrach/Khrapko‑type spotting method.
• Reaches: motivation and the density limitations (claims 2–3); supplies "obvious to try" support for miniaturized deposition.

Ground C — Abouzied (+ Lehrach/Khrapko): the gridded, barrier‑separated multi‑array substrate and open‑face assay

• Abouzied discloses hydrophobic compartments on a membrane separating reagent regions "to minimize use of reagents," with multiplexed detection and image analysis. The Background additionally admits QA Life Sciences sells a gridded membrane and that Pall's sealed 96‑well filter plate avoids cross‑contamination.
• Motivation: Screening many arrays on one sheet ("array of arrays") to avoid handling 96 separate sealed chambers is expressly identified in the Background as a goal; Abouzied supplies a partition‑based solution.
• Reaches: the barrier‑grid/multi‑cell substrate and open‑face hybridization subject matter (claims of the family — e.g., US 6,110,426, US 7,625,697 — rather than US 5,807,522's seven method claims). The patent's own distinction — that Abouzied's hydrophobic barrier does not "completely seal the pores" so reagents leak — is a teaching‑away/objective‑indicia counter (see § VIII).

Ground D — Lehrach/Khrapko + routine optimization: the recited volume ranges and the open‑sided‑channel design choice

• Volume (claim 1's 0.002–2 nl; claims 6–7's 0.002–0.25 nl): Khrapko's 100 µm dots correspond to ~0.25 nl, precisely the upper bound of claims 6–7; the specification's own Table 1 ties 20–200 µm tips to 2 pl–2 nl. Under In re Aller / KSR, where the art recognizes a parameter (spot volume) as a result‑effective variable and the field is under miniaturization pressure, selecting the disclosed sub‑nanoliter regime is routine optimization. The Background's stated need for "micro‑sized" regions with "well‑defined" (picomole‑range) amounts supplies the pressure.
• Open‑sided channel (claims 4–5): A challenger would argue that making the capillary open‑sided is a predictable design choice — the specification itself recites the expected advantages (easy washing/drying between reagents, less clogging, no need for a perfectly faced bottom surface, passive capillary loading from microwell plates). An open capillary is the natural expedient for an artisan who must wash and refill the same dispenser many times per array — precisely the Lehrach deficiency.
• Reaches: claims 4–7 and the volume/step‑height limits within claim 1, but only conditionally — the open‑sided‑channel rationale is drawn almost entirely from the inventor's own disclosure, and using it as the motivation risks impermissible hindsight.

Ground E — Drmanac / Nelson / Riles: motivation to make the arrays denser and to use them for expression and mapping

• These references supply the demand‑side motivation (SBH, physical mapping, expression monitoring) that makes miniaturization and multi‑plexing desirable, and they confirm the desirability of "many assays on one support."

VI. Why a PHOSITA would have combined these references (motivation synthesis)

1. Identified problem in the art (Lehrach's admitted variable spot volume; limited replication per dip). KSR permits combining references where the prior art itself points out the deficiency.
2. Recognized, finite improvement path — replace a variable‑transfer solid pin with a metered liquid‑carrying dispenser and iterate (Khrapko).
3. Established field direction — high‑density, addressable arrays on solid supports (Fodor, Pirrung, Southern, Khrapko) with sub‑nanoliter features and optical readout.
4. Parallel partitioning solution for cross‑contamination (Abouzied, QA Life Sciences, Pall) to enable "array‑of‑arrays" processing.
5. Predictable results — no new chemistry or biology was required; the claims are directed to mechanical deposition of known reagents onto known supports.

VII. The decisive gap — the open‑capillary, meniscus‑breaking "tap" dispenser

The analysis is candid here: none of the references cited in the patent (or in its Background) discloses, suggests, or renders obvious the claim‑1 dispensing mechanism taken as a whole — specifically:

• an elongate capillary channel (as opposed to a solid pin or a closed pipette) that holds the reagent and presents a meniscus at a tip region; and
• tapping that tip against the support with an impulse effective to break the meniscus, metering a defined 0.002–2 nl droplet as a consequence.

Lehrach's pins transfer a surface film by contact — there is no channel and no meniscus to break. Khrapko's micropipette is a closed tube metering by displacement, not by meniscus rupture on contact. Fodor, Pirrung, and Southern build arrays by in‑situ synthesis, a different paradigm. Drmanac/Nelson/Riles disclose applications, not fabrication hardware.

Because claim 1's only non‑trivial contribution over this record is the dispenser mechanics, and because the skilled liquid‑handling artisan of 1994 knew closed capillaries, quill/pen nibs, and solid pins but was not shown any open‑capillary/impulse‑tap dispenser in this record, a § 103 challenge built solely on the patent's own cited references would likely fail on claim 1, and would therefore fail on claims 2–7 as well (all dependents).

To actually mount a serious § 103 attack on claim 1, a challenger would need art outside this list — e.g., micro‑capillary/quill‑type transfer devices, open‑channel split‑pin or "tweezer" dispensers, or impulse/piezo contact‑transfer dispensers from the liquid‑handling and analytical‑instrumentation arts. I did not locate such a reference in this record (a targeted search for open split‑pin capillary spot dispensers returned no results), so I will not assert one exists. The honest conclusion is: the cited references render the environment of the invention obvious (high‑density deposited nucleic‑acid arrays on solid supports, partitioned multi‑array formats, sub‑nanoliter volumes), but not the claimed tap‑dispensing mechanism itself.

VIII. Counterarguments the patent owner would raise (and their strength)

1. No teaching or suggestion of the meniscus‑break/tap mechanism — strongest defense; directly rebuts Grounds A–C as to claim 1.
2. Teaching away — Fodor/Pirrung/Southern steer toward in‑situ synthesis (with its admitted <20‑base limitation), i.e., away from deposited long polynucleotides; Abouzied's barrier is admitted not to seal pores, steering away from membrane‑based partitioning for DNA hybridization.
3. Unexpected results / objective indicia (Graham factor 4):
   • The method produces reproducible, well‑defined sub‑nanoliter volumes where Lehrach's pin transfer was admittedly "highly variable" — an unexpected performance gain over the closest mechanical art.
   • Broad industry adoption and licensing: the family litigated against Affymetrix/Incyte in the late 1990s–2000s, and Incyte asserted US 5,807,522 (with US 6,110,426) in Incyte Genomics, Inc. v. Invitrogen Corp., No. 3:01‑cv‑02141 (S.D. Cal.) (Stanford NPE Litigation Database, https://npe.law.stanford.edu/patent/5807522). Evidence of copying and widespread licensing supports non‑obviousness.
   • Praise / scientific recognition of the two‑color cDNA microarray (Example 2; Schena et al. 1992 and the later Science 1995 paper) — a nexus to the claimed fabrication method as enabling the applications.
4. No reasonable expectation of success for the open‑capillary/impulse‑tap design at the priority date — the artisan had no basis to predict that a meniscus would rupture at the precise moment of contact to meter a defined droplet, or that an open channel would reliably hold and release picoliter volumes.
5. Hindsight concern — the open‑sided‑channel motivation (Ground D) is drawn from the inventor's own disclosure and should be discounted.

IX. Bottom line

Assessment: On the record of prior art cited by US 5,807,522 itself, independent claim 1 — and therefore all of claims 2–7 — would likely be sustained against a § 103 challenge, because the cited references do not disclose or suggest the claimed open‑capillary dispenser whose meniscus is deliberately broken by an impulse of tapping contact to meter a 0.002–2 nl droplet. The cited references render obvious the context and goals (high‑density deposited nucleic‑acid arrays on solid supports, partitioned multi‑array substrates, sub‑nanoliter spotting) and would support invalidity of narrower, format‑only claims — but not of claim 1's dispensing mechanism. A challenger would need additional, non‑listed art directed to open‑capillary/impulse‑tap dispensing (which I could not identify in this record) to make claim 1, and with it the whole patent, obvious; I do not assert that such art exists or does not exist, only that it is absent from the patent's own cited references.

Caveats / uncertainties:

• Abouzied (March 1994) is only ~3 months before the 1994‑06‑17 priority date; its status as § 103 prior art is a factual question (it is likely available under pre‑AIA § 102(a)/(e) rather than § 102(b)). Its force here rests largely on the patent's own Background admission of the same gridded‑membrane/barrier technologies (QA Life Sciences, Pall, Hyseq), which removes much of that uncertainty.
• I did not locate any AIA trial proceeding or Final Written Decision on this patent; no PTAB claim‑level disposition exists to cite (consistent with prior sections). This is a documentary analysis of the cited references, not a validity judgment by any tribunal.
• Searches confirmed the content of Lehrach, Khrapko, Fodor, and Abouzied; a targeted search for open split‑pin capillary spot‑dispenser prior art returned no results, so no such reference is relied upon above.

Sources: Google Patents record and full text of US 5,807,522A (https://patents.google.com/patent/US5807522/en); Lehrach et al. 1990 (as quoted in US 2011/0130306A1 and WO 2000032044A1); Khrapko et al. 1991, DNA Seq. 1:375–388 (https://pubmed.ncbi.nlm.nih.gov/[1768861](/patent/1768861)/); Fodor et al. 1991, Science 251:767–773 (https://pubmed.ncbi.nlm.nih.gov/[1990438](/patent/1990438)/); Abouzied & Pestka 1994, J. AOAC Int. 77(2):495–501 (https://pubmed.ncbi.nlm.nih.gov/[8199485](/patent/8199485)/); Stanford NPE Litigation Database (https://npe.law.stanford.edu/patent/5807522).