US 11402395

I'll search for authoritative information on this patent number, including any litigation activity.

Let me check for any litigation or CAFC docket activity specifically involving this patent.

Let me pull the actual claim set to accurately summarize the independent claims.

US 11,402,395 B2 — Analyst Summary

Scope note / grounding: My summary below is built on (a) the authoritative full text you supplied (Google Patents, fetched 2026‑09‑24) and (b) targeted web searches of the published front‑page PDF, Google Patents, and family records. I was not able to retrieve the verbatim granted claim set of US 11,402,395 from an authoritative source in this session, so the claim overview is derived from the specification's "Features of the Invention" and the claim structure of sibling family members — flagged as such below. I also found no Court of Appeals for the Federal Circuit 2026 docket naming US 11,402,395; see the litigation section.

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1. Bibliographic Data (as stated on the face of the patent)

Note on the dual 2022/2026 "dates": the "Current Date: April 26, 2026" in your instructions is later than the patent text's fetch date. I have used the patent's own dates verbatim and treated the 2026 date as the assessment date.

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2. Abstract (verbatim)

"Compounds and methods for use in detecting gabapentin in a sample suspected of containing gabapentin are disclosed. Gabapentin derivatives are used to produce gabapentin conjugates. A gabapentin‑immunogenic carrier conjugate may be used as an immunogen for the preparation of an anti‑gabapentin antibody. A gabapentin‑detectable label may be used in a signal producing system in gabapentin assays."

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3. Technical Overview

The patent sits in the therapeutic drug monitoring (TDM) space for gabapentin ((1‑aminomethyl)cyclohexane‑1‑acetic acid). The invention provides:

• Gabapentin derivatives — haptens (compounds sharing gabapentin's core but bearing a chemical "handle") that can compete with gabapentin for binding to an anti‑gabapentin antibody, defined by three positional variants:
  • Formula I — extension from the amine group of gabapentin,
  • Formula II — extension from the carbonyl/carboxyl group,
  • Formula III — extension from carbon 4 of the cyclohexane ring.
• Gabapentin conjugates — those derivatives covalently linked to a moiety of interest: immunogenic carriers (e.g., KLH, BSA), detectable labels (enzymes such as G6PDH, alkaline phosphatase, β‑galactosidase, horseradish peroxidase; fluorophores; quenchers; radioisotopes), or supports/particles.
• Anti‑gabapentin antibodies raised against the immunogenic conjugates (polyclonal or monoclonal, including Fab/F(ab′)₂/Fv/scFv).
• Immunoassay methods and kits — homogeneous (e.g., competitive enzyme immunoassay using a gabapentin–G6PDH conjugate; see FIG. 5 and the FIG. 6 calibration curve) and heterogeneous formats, with calibration standards in synthetic or human‑serum matrix.

Representative chemistry: -X-W-L-Z, where X is NH (or a heteroatom/lower alkyl for the C‑4 series), W is a lower alkyl or carbonyl, L is a linker of 0–40 carbons and 0–6 heteroatoms, and Z is H, alkyl, a reactive functional group (halogen — typically Br or I —, SH, NH₂, maleimidyl, haloacetamide, succinimidyl, etc.), or a moiety of interest. Specific exemplified derivatives include —NH—(CH₂)ₘ—SH, —NH—CO—(CH₂)ₙ—Br, and —NH—(CH₂)ₒ—S—CH₂—CO—CH₂—Br, with m, n, o independently 2 or 3. A notable enzyme embodiment is a G6PDH variant bearing a non‑native cysteine per subunit (cross‑referenced to U.S. Pat. Nos. 6,033,890, 6,090,567, and 6,455,288).

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4. Plain‑Language Overview of the Independent Claims

Confidence caveat: The Google Patents text you supplied contains the specification but not the verbatim "Claims" section, and a direct claims fetch timed out. What follows is therefore an informed reconstruction based on (i) the specification's "Features of the Invention" list and (ii) the claim tree of a sibling family member (US 11,867,705), whose claim 1 is a compound claim and whose claims 2–8 recite the same linker/W/Z limitations and specific structural sub‑genera seen in this family. Treat claim wording as indicative, not verbatim.

The 17 claims appear to fall into the classic four‑independent‑claim pattern of this family:

1. Independent claim 1 — the compound (gabapentin derivative). A chemical compound built on gabapentin's cyclohexane core where one of three positions (R¹ on the amine side, R² on the carboxyl side, or R³ on the ring carbon‑4) carries an -X-W-L-Z substituent chain, with X being NH (or a heteroatom/lower alkyl at C‑4), W a lower alkyl or carbonyl, L a linker of 0–40 carbons and 0–6 heteroatoms, and Z being H, an alkyl, a reactive functional group capable of reacting with a reactive partner to form a covalent bond, or a moiety of interest — or a salt thereof. Dependent claims 2–8 narrow the linker definitions, W = methyl, and specific structural sub‑genera (the FIG. 2 compounds).

2. An independent claim to a gabapentin conjugate. The same derivative core, but with Z as a moiety of interest, i.e., the gabapentin hapten covalently attached (optionally through the linker) to an immunogenic carrier, detectable label, or support. Dependent claims narrow the carrier (KLH, BSA; hemocyanins/globulins/albumins/polysaccharides), the enzyme (G6PDH, including cysteine‑variant G6PDH), and the detectable label type.

3. An independent claim to a method for detecting gabapentin. Steps: (a) combine a sample suspected of containing gabapentin with an anti‑gabapentin antibody capable of forming a gabapentin–antibody complex, optionally in the presence of a gabapentin–detectable‑label conjugate that competes for antibody binding; and (b) detect the presence or absence of the complex — e.g., by reading enzyme activity of the gabapentin–enzyme conjugate — where the signal indicates the presence or absence (or amount) of gabapentin. Dependent claims specify homogeneous vs. heterogeneous format, quantitative determination, and the biological sample (human blood or blood‑derived, e.g., serum/plasma).

4. Independent claims to an antibody and to a kit. One claim recites an antibody that specifically binds gabapentin (narrowed in dependents to monoclonal, and to Fab/Fab′/F(ab′)₂/Fv/single‑chain fragments). A further independent claim recites a kit comprising an anti‑gabapentin antibody capable of specifically binding gabapentin plus a gabapentin calibration standard, with dependents adding a gabapentin–detectable‑label conjugate and, where the label is an enzyme, a substrate for the enzyme.

The principal practical effect: the claims cover (i) the hapten tool compounds, (ii) immunogens and assay tracers made from them, (iii) the immunoassay method for measuring gabapentin, and (iv) the antibody and kit embodiments commercialized as the ARK Gabapentin Assay.

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5. Litigation / CAFC Docket Search — US 11,402,395

Finding: I located no Court of Appeals for the Federal Circuit docket, and no district‑court or ITC action, specifically naming U.S. Patent No. 11,402,395. My searches of the CAFC/2026 docket space and general litigation sources returned nothing tying this particular number to an appeal or suit.

What does exist is family‑level litigation involving different patents in the same ARK gabapentin portfolio, which I report so as not to conflate them:

• ARK Diagnostics, Inc. v. Acro Biotech, Inc., Hangzhou AllTest Biotech Co., Ltd., et al., No. 5:21‑cv‑00871 (C.D. Cal., filed 2021) — complaint for infringement of U.S. Patent No. 10,203,345 (the "'345 Patent"), directed to the ARK Gabapentin Assay. Counsel of record: Maynard Cooper & Gale LLP. The complainant describes the '345 Patent as protecting the ARK Gabapentin Assay.
• ITC Investigation (Section 337) — "Certain Gabapentin Immunoassay Kits and Test Strips, Components Thereof, and Methods Therefor," instituted following a complaint filed Dec 2, 2020 by ARK Diagnostics (amended Dec 23, 2020), published at 85 FR (notice 2021‑01548, Jan 25, 2021). Asserted patents: 8,828,665 (the "'665 patent") and 10,203,345 (the "'345 patent") — not 11,402,395.

Important distinction: The '665, '345, '880, '835, and '395 patents share the "Compounds and methods for use in detecting gabapentin" family and the same inventors, but they are separate patent numbers with separate claims. The Google Patents "Family has litigation" flag on US 11,402,395 reflects family‑level (Darts‑IP) litigation linkage, not necessarily litigation asserting this specific patent. Do not read the Acro/AllTest or ITC matters as asserting '395 without confirming the pleadings.

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6. Explicit Uncertainty Flags

• Verbatim claim language of US 11,402,395 was not retrieved. The claim overview in §4 is a reconstruction from the specification and sibling claims (US 11,867,705, whose claim 1 is a compound claim with the same linker/W/Z framework). The exact claim count split (how many of the 17 claims are compound vs. conjugate vs. method vs. antibody vs. kit) is inferred, not confirmed.
• No CAFC 2026 docket confirmed for this number. Absence of a search hit is not proof of absence; I did not have direct access to PACER/CAFC docket systems, only web search.
• The patent text contains a figure‑labeling inconsistency (FIG. 7A is described as bromoacetylation of KLH/enzyme, while "FIG. 8A represents an exemplary thiolation of KLH and G6PDH," and FIGS. 8A–K are elsewhere described as the synthetic schemes) — likely an internal typographical error in the specification. I have not auto‑corrected it.
• Inventor Byung Sook Moon's city differs between sources (Palo Alto per the '395 front page; Los Altos Hills per later family filings) — this is a residence change over time, not a discrepancy in identity.

Key sources: US11402395B2 front‑page PDF (patentimages.storage.googleapis.com/64/4e/4a/0a0f57658e3e74/US11402395.pdf); Google Patents US11402395B2; Justia Patents (family member 11867705 claim listing); onscope IP‑owner record for Ark Diagnostics; Docket Alarm (ARK v. Acro Biotech, 5:21‑cv‑00871 complaint); Federal Register 2021‑01548 (ITC Section 337 notice).

I'll search for litigation involving US patent 11402395 using several sources.

Let me search more targeted litigation databases.

Let me verify whether any litigation specifically names the '395 patent, and check for more recent cases.

Summary: Litigation involving US 11,402,395

No litigation specifically asserting or naming U.S. Patent No. 11,402,395 ("the '395 patent") was found in the sources searched. To be precise about what I found and how I searched:

What I searched

• Google Patents entry for US11402395B2 (which carries a "Family has litigation" flag linking to a Darts‑ip family record, family no. 39707001)
• USITC EDIS / Federal Register notices, govinfo.gov
• Docket Alarm, RPX Insight, CourtListener/Justia, and general web searches for the literal number "11,402,395" and for ARK Diagnostics gabapentin litigation

What the litigation record actually shows

The ARK Diagnostics gabapentin‑immunoassay enforcement campaign is real and well documented, but it asserted U.S. Patent Nos. 8,828,665 ("'665 patent") and 10,203,345 ("'345 patent") — neither of which is the '395 patent. These three patents share the same 2007‑02‑16 priority family, which is why the '395 Google Patents page shows a "Family has litigation" indicator, but the '395 patent does not appear in any pleading I located.

The known cases are:

1. ITC Section 337 Investigation — Certain Gabapentin Immunoassay Kits and Test Strips, Components Thereof, and Methods Therefor

• Complainant: ARK Diagnostics, Inc. (Fremont, CA)
• Respondents (14): Hangzhou AllTest Biotech Co., Ltd. (CN); Shanghai Chemtron Biotech Co., Ltd. (CN); Chemtron Biotech Co., Ltd. (San Diego, CA); Zhejiang Orient Gene Biotech Co., Ltd. (CN); Healgen Scientific, LLC (Houston, TX); Kappa City Biotech, SAS (France); 12PanelMedical, Inc. (Sarasota, FL); Acro Biotech, Inc. (Rancho Cucamonga, CA); AlcoPro, Inc. (Knoxville, TN); American Screening, LLC (Shreveport, LA); Confirm Biosciences, Inc. (San Diego, CA); Mercedes Medical, LLC (Lakewood Ranch, FL); TransMed Co., LLC (Alpharetta, GA); Transmetron, Inc. (Salt Lake City, UT)
• Jurisdiction: U.S. International Trade Commission
• Case number: Inv. No. 337‑TA‑1239
• Filing date: Complaint filed December 2, 2020 (supplement same day; amended complaint Dec. 23, 2020); investigation instituted January 19, 2021 (86 FR 6918‑19)
• Patents asserted: '665 and '345 patents (claims 1‑3, 6, 7, 9, 14, 17, 18, 20, 21 of '665; claims 1, 2, 7, 8, 11, 12, 19, 20, 26, 27 of '345)
• Status/outcome: Terminated. Most respondents settled, consented to orders, or were terminated on partial withdrawal of the complaint (12Panel entities, TransMed, Mercedes Medical, AlcoPro, American Screening, Chemtron Biotech, Hangzhou AllTest, Acro Biotech, Zhejiang Orient Gene, Healgen Scientific, Shanghai Chemtron). Kappa City Biotech was found in default; on July 25, 2022 the Commission issued a limited exclusion order against Kappa City (no cease‑and‑desist order, as it is a foreign respondent), with a 100% bond.

2. ARK Diagnostics, Inc. v. Acro Biotech, Inc. et al

• Plaintiff: ARK Diagnostics, Inc.
• Defendants: Acro Biotech, Inc. and Hangzhou AllTest Biotech Co., Ltd. (plus Does 1‑10)
• Jurisdiction: U.S. District Court, Central District of California
• Case number: 5:21‑cv‑00871
• Filing date: May 19, 2021
• Patent asserted: '345 patent only
• Status: Pleaded as a companion to the ITC action; I did not locate a final judgment in the sources searched. (Note: AllTest/Acro were among respondents terminated in the ITC investigation based on partial withdrawal of the complaint.)

Important caveats

• The '395 patent is a different patent from the '665 and '345 patents. Because these share a common priority family, third‑party family‑level litigation databases (like the Darts‑ip "Family has litigation" link on the Google Patents page) may roll up family litigation under a single family record. A "family has litigation" flag is not evidence that the '395 patent itself was asserted.
• Do not assume the ITC or C.D. Cal. cases involved the '395 patent; the pleadings and Federal Register notices expressly identify only the '665 and '345 patents.
• The '395 patent issued August 2, 2022, after the ITC complaint (Dec. 2020) and the district court complaint (May 2021) were filed, which is consistent with it not appearing in those pleadings. I found no post‑issuance suit asserting the '395 patent.
• I was unable to complete additional targeted searches on the Unified Patents litigation portal and PACER within the search budget, so this should not be treated as an exhaustive negative. If a broader confirmation is needed, I would recommend a direct PACER/Docket Alarm docket search and an RPX/Unified Patents lookup filtered to Patent No. 11,402,395, plus a review of the Darts‑ip family record (family 39707001) referenced on the Google Patents page.

Bottom line: Based on the sources searched, no litigation is known to specifically involve US 11,402,395. The relevant ARK Diagnostics gabapentin litigation (337‑TA‑1239 and C.D. Cal. 5:21‑cv‑00871) asserted only US 8,828,665 and US 10,203,345.

PTAB Proceedings on US 11,402,395 — Analysis

Proceedings overview

Total AIA trial proceedings on file: 0. The USPTO Open Data Portal structured block returns no IPR, PGR, or CBM for US 11,402,395, and independent web searching surfaced no petition, institution decision, FWD, or Federal Circuit appeal directed at this patent (or, so far as I could find, at any of its siblings U.S. 9,522,880 / 10,203,345 / 11,402,395 / 11,525,835 / 11,867,705). The defensive posture this gives a defendant is unusual but not comfortable: the patent has not been tested at the Board, so there is no canceled claim to point to and no § 315(e)(2) estoppel helping you — but equally, there is no adverse FWD holding any claim patentable that you would have to overcome. The absence of PTAB activity here is not a sign of patent strength; it is best explained by (a) the patent's short remaining life (statutory term to 2028-02-15, per the ODP record) and (b) the fact that ARK's public enforcement campaign ran through the ITC, not the PTAB, and ended in respondent-by-respondent settlements and withdrawals.

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Proceedings

None. No AIA trial proceeding exists for US 11,402,395 as of 2026-09-29.

For completeness, the closest-adjacent activity is not PTAB activity and should not be described as such:

Sources: Google Patents US 11,402,395 · USITC News Release 21-006 (337-TA-1239 institution) · ITC institution notice, 86 FR 6918 · ITC final notice, 87 FR (2022-07-29) · Darts-ip family litigation record

Caveat you should price in: the ODP ingest is not instantaneous, and PTAB filings appear in Patent Trial Practice Guide-style public dockets (PTAB E2E / USPTO PTAB Decisions) before they are always reflected in third-party indexes. Before you finalize a non-infringement or invalidity budget, verify directly at PTAB E2E and USPTO PTAB Decisions by patent number, and check Patent Center for any ex parte reexamination certificate (a reexam would not show up in an AIA-trial feed at all). I did not find one; I am not certifying one does not exist.

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Strategic summary

Claim status. Because no AIA trial has ever been instituted against US 11,402,395, no claim has been canceled, and no claim has been adjudicated patentable by the Board. All 17 claims stand exactly as issued on 2022-08-02. That is materially different from the familiar "narrowed-through-IPR" posture: there is no amended claim set, no certificate of correction narrowing the Markush formula, and no FWD language you can quote to a plaintiff. The claim set (per the face of the patent, 17 claims) is directed to gabapentin derivatives/conjugates recited through the formula appearing in the '395 classification data ([1*]CC1(CC([2*])=O)CCC([3*])CC1), together with method, antibody, and kit subject matter described in the specification; treat any precise claim-to-subject-matter map as unverified until you have read the printed claims, which I have not done at claim-number granularity here.

Estoppel landscape. With zero AIA trials, no § 315(e)(2) estoppel attaches to anyone — not to the 337-TA-1239 respondents, not to the C.D. Cal. defendants, not to any privy. Every § 102/§ 103 ground based on printed publications is therefore still available to a new petitioner, subject only to: (i) the § 315(b) one-year bar running from service of a complaint alleging infringement of the '395 patent (critical — if your client has been served and the year is running, that deadline governs everything else); (ii) the § 315(a)(1) bar if your client filed a DJ action of invalidity first; and (iii) the Board's § 325(d) discretion, which is a live risk here because the '395 patent's own prosecution record cites art including EP 0659751, EP 1470825, and Chen et al., J. Agric. Food Chem. 44:1352–1356 (1996). Do not build a petition on those references.

Pattern signals. Two are notable and cut in opposite directions. First, the same patent owner has now asserted related family members at least twice (ITC 337-TA-1239 in 2020–22; C.D. Cal. 5:21-cv-00871 in 2021), which tells you ARK is a repeat, sophisticated enforcer with a real commercial product behind the patents (ARK™ Gabapentin Assay, cleared via 510(k) K101574) rather than a non-practicing entity. Second, fourteen ITC respondents and multiple district-court defendants generated no IPR petitions at all. That is empirically unusual for a well-asserted patent. The most plausible drivers: small per-respondent U.S. volumes making IPR economics unattractive; early settlement at the ITC; and the 2028-02-15 expiry, which sharply discounts the value of an FWD that would land around 2025–2026 even if instituted promptly. There is no defensive aggregator (e.g., Unified Patents) in the chain that I could identify. If your client has real U.S. revenue exposure in the gabapentin-immunoassay space, that gap in the record is an opportunity, not a reassurance.

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Recommended next steps

1. Confirm the zero-count before relying on it. Search PTAB E2E and the PTAB Decisions library by "11,402,395," and run a Patent Center transaction history check for reexamination or reissue activity. The ODP block is the canonical source, but it is a snapshot.

2. Calendar the § 315(b) bar today. If your client has been served with a complaint asserting the '395 patent, the one-year clock is your single most important date. There is no IPR on file to piggyback on and no estoppel to work around — you would be the first petitioner and would control the record.

3. Do not cite the ITC proceedings as an invalidity win. The ITC case was resolved by consent orders, settlements, withdrawals, and one default judgment — I found no merits holding of invalidity or unpatentability. Representing it as such to a court or to opposing counsel is not supportable.

4. Build any petition on art outside the '395 prosecution history. Because there is no FWD and no prior institution, you get a clean § 325(d) slate except for the references already of record (EP '751, EP '825, Chen 1996). Focus the prior-art search on 2006–2008-era hapten-linker-enzyme conjugation chemistry for small-molecule TDM assays (G6PDH conjugation, bromoacetyl/thiol coupling, immunogen design) — the very areas the specification relies on — and on the ARK product literature and 510(k) filings predating the 2008-02-15 non-provisional filing.

5. Consider the term math before you spend. An IPR filed in late 2026 would be unlikely to reach an FWD before the 2028-02-15 expiry, and the patent is subject to a terminal disclaimer. Weigh the IPR against a district-court § 112/§ 102 case, an ITC design-around, or a Fintiv-free fast-track petition filed immediately.

6. Preserve the ITC record. The 337-TA-1239 respondents (notably Zhejiang Orient Gene/Healgen, which publicly claimed it chose to litigate rather than settle) generated claim-construction and non-infringement positions on the sibling '345 patent that may transfer usefully to the '395 claims. Those are public via ITC EDIS and are not subject to any PTAB estoppel.

I'll research the assignment record and related ownership information for US 11402395.

Let me search for the specific assignment recordation details and ARK Diagnostics' corporate status.

Let me try to find the specific USPTO assignment recordation details (reel/frame) and check for any name-change records.

Ownership Analysis — US 11,402,395 B2

Scope note / data limitation (read first): I was able to retrieve the conveyance types and dates for this patent from Google Patents' legal-events record and to corroborate ARK Diagnostics' corporate history from press releases, FDA records, and court dockets. I was not able to retrieve the underlying reel/frame numbers or the correspondent-of-record data from the USPTO Assignment Center (assignmentcenter.uspto.gov) — that interface does not expose those fields in a form I could fetch, and I will not invent reel/frame values. Where reel/frame is unknown below, it is marked [not retrievable] rather than guessed. Verify at the Assignment Center search page: https://assignmentcenter.uspto.gov/ (and the older mirror https://assignment.uspto.gov/patent/index.html).

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Inventors

• The application (Ser. No. 17/478,639) was filed 2021-09-17 and all four inventors assigned to ARK Diagnostics, consistent with employee invention-assignment practice.
• Priority lineage: the family claims priority to 2007-02-16, so this is a long-chain continuation. The asserted sibling patents in the same family — US 8,828,665 and US 10,203,345 — were the subject of ARK's ITC action (see below), confirming the inventors' work dates back to the original 2007 filing.
• Unusual-pattern check — no finding. There is no evidence in the record that any inventor departed ARK within 12 months of filing; the assignment was a routine employer take-up recorded about one month after filing. I could not independently verify current employment status of the individual inventors, so a departure pattern is unclear / not observed, not affirmatively absent.

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Original assignee

ARK Diagnostics, Inc. — Fremont, California (48089 Fremont Blvd, Fremont, CA 94538). Named sole original assignee on the face of the patent.

• Primary line of business: developer and manufacturer of specialty in vitro diagnostic (IVD) immunoassays for therapeutic drug monitoring (TDM) and drugs-of-abuse testing, using its Enzyme-Multiplied Immunoassay Technique (EMIT). Founded 2003.
• Product embodying the claims — YES, shipped. ARK markets the ARK™ Gabapentin Assay (product 5025-0001-00), with an ARK™ Gabapentin Calibrator and ARK™ Gabapentin Control. The assay was cleared via FDA 510(k) K101574, a homogeneous enzyme immunoassay using anti-gabapentin rabbit polyclonal antibody and gabapentin labeled with bacterial G6PDH — i.e., the exact conjugate/assay chemistry described in this patent. Product literature available at ark-tdm.com (© 2025 ARK Diagnostics, Inc.). Assays are sold in 30+ countries.
• Corporate status — OPERATING, and recently re-capitalized:
  • Acquired by South Korean specialty-chemical company Soulbrain Holdings (KRX: 036830) in 2018 (stock acquisition; ARK remained the named patent owner, which is why no patent-record assignment to Soulbrain appears).
  • Oct 2025: ARCHIMED Diagnostics (European healthcare PE) closed a carve-out of a 60% stake from Soulbrain, at a $428M enterprise value; Soulbrain reinvested for a 40% stake under a joint-venture agreement. (archimed.group news release, 2025-10-28; Dechert advised ARCHIMED, 2025-11-03.)
  • Status: operating, not dissolved, not in bankruptcy.

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Assignment timeline

Only two post-issuance/recorded events appear for this patent. Both are documented in Google Patents' legal-events record for US 11,402,395 B2. Reel/frame and correspondent were not retrievable from my sources.

• 2021-10-12 (recorded) — Reel [not retrievable] / Frame [not retrievable]

  • Conveyance: Assignment ("ASSIGNMENT OF ASSIGNORS' INTEREST / SEE DOCUMENT FOR DETAILS")
  • Assignor: MOON, BYUNG SOOK; OROZCO, ALEJANDRO A.; VALDEZ, JOHNNY JOSE; HELMS, MICHAEL KEVIN (the four inventors)
  • Assignee: ARK DIAGNOSTICS, INC.
  • Correspondent: [not retrievable] — flag: counsel/prosecution address for ARK patent filings has previously been Morgan, Lewis & Bockius LLP (SF) in related ARK family documents, but I could not confirm this was the correspondent on this reel; do not treat as a finding.
  • Context: Internal/employee take-up — inventors assign to their employer; ordinary, not a monetization event.

• 2025-10-22 (recorded) — Reel [not retrievable] / Frame [not retrievable]

  • Conveyance: Security Interest (SECURITY INTEREST — grant of collateral, not a transfer of title)
  • Assignor: ARK DIAGNOSTICS, INC.
  • Assignee: ARES CAPITAL CORPORATION, as Administrative Agent
  • Correspondent: [not retrievable] — no recurrence data available to assess.
  • Context: Securitization / LBO financing — collateral grant tied to ARK's 2025 re-capitalization around the ARCHIMED carve-out. Ares Capital is a publicly traded business-development company (private-credit lender), i.e., the lender of record, not an owner of the patent.

Finding on the Soulbrain and ARCHIMED deals: Neither the 2018 Soulbrain acquisition nor the 2025 ARCHIMED carve-out appears as a patent assignment in this patent's record — consistent with both being equity/share transactions in which ARK Diagnostics remained the record patent owner. The only title movement on the face of the US record is inventors → ARK Diagnostics.

If the Assignment Center shows additional records beyond these two (e.g., a change-of-name or a 2018/2025 collateral instrument for the Soulbrain or ARCHIMED financings), those would be the missing links — but I found no evidence of a transfer of title away from ARK Diagnostics.

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Timeline diagram

timeline
    title Ownership of US 11402395
    2007 : Priority date of family
    2021 : Application filed by ARK Diagnostics
         : Inventors assign to ARK Diagnostics
         : Recorded 12 Oct 2021
    2022 : Patent issued 2 Aug 2022
    2025 : ARK Diagnostics grants security interest
         : To Ares Capital as administrative agent
         : Recorded 22 Oct 2025
         : ARCHIMED acquires 60 percent stake

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NPE / troll-pattern signals

1. Shell-entity transfer — NOT PRESENT. No assignment of this patent to any "IP / Holdings / Licensing / Ventures" entity. The only recorded assignment runs to the operating company ARK Diagnostics; the only outbound record is a security interest to a lender, which conveys no ownership.

2. Known asserter in the chain — NOT PRESENT. Assignees of record are ARK Diagnostics (operating IVD maker) and Ares Capital Corporation (BDC/private-credit lender). Neither matches any entity on the RPX / Unified Patents / Acacia / Marathon / Intellectual Ventures / Wi-LAN / Conversant NPE lists.

3. Repeat correspondent across the chain — UNCLEAR / INSUFFICIENT DATA. Correspondent-of-record data was not retrievable for either event, so recurrence cannot be tested. No finding either way.

4. Cascading transfers — NOT PRESENT. Two events, ~4 years apart, of different conveyance types; no chained LLCs, no <24-month cascade.

5. Pre-litigation transfer — NOT PRESENT (inverted). The 2021-10-12 inventor→ARK assignment occurs after ARK's own Dec 2, 2020 ITC complaint and May 2021 district-court suits on sibling patents, so it cannot be a plaintiff-side "set up the chain to assert" transfer. Conversely, ARK's assertion is that of an operating patent owner, not a buyer assembling standing.

6. Bankruptcy fire-sale — NOT PRESENT. No Chapter 7/11. ARK was sold in a solvent $428M carve-out (Oct 2025), not a distressed asset sale.

7. Privateering — NOT PRESENT. ARK asserts its own patents in its own name against importers/competitors (below); there is no operating-company-to-NPE handoff.

8. Defensive aggregator — NOT PRESENT. Chain does not terminate at RPX, AST, LOT, Unified Patents, or OIN.

Assertion context (evidence of operating-company litigation, weighing against NPE status):

• ITC Inv. No. 337-TA-1239, Certain Gabapentin Immunoassay Kits and Test Strips — complaint filed 2020-12-02 by ARK Diagnostics, Inc. of Fremont, CA, asserting US 8,828,665 and US 10,203,345 (same 2007-02-16 family) against ~14 importers/retailers (Hangzhou AllTest/Acro Biotech, Healgen Scientific, Chemtron, Zhejiang Orient Gene, 12Panel, AlcoPro, American Screening, etc.). Investigation instituted 2021-01-19; terminated on complainant's withdrawal 2022-07-25.
• District-court suits by ARK Diagnostics in the same period: 5:21-cv-00871 (C.D. Cal. v. Acro Biotech), 4:21-cv-01652 (S.D. Tex. v. Healgen Scientific), 2:21-cv-04205, 3:21-cv-00845 (v. Chemtron). ARK's Rule 7.1 disclosure in the Healgen case identified Soulbrain Holdings Co., Ltd. as corporate parent — confirming the operating company, not an NPE shell, was the plaintiff.

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Verdict

Operating-company assertion.

Justification: The record shows a single inventor→employer assignment (recorded 2021-10-12 to ARK Diagnostics, Inc.) and a lender's security interest (recorded 2025-10-22 to Ares Capital Corporation as administrative agent) — no transfer of title to any licensing entity, and no NPE, aggregator, or bankruptcy in the chain. ARK Diagnostics is a 30+-country seller of the FDA-cleared ARK™ Gabapentin Assay that embodies the claimed conjugate chemistry (510(k) K101574), and it asserted the same patent family in its own name against importers/competitors (ITC 337-TA-1239; C.D. Cal. 5:21-cv-00871; S.D. Tex. 4:21-cv-01652). The Ares record is standard LBO collateral for the October 2025 ARCHIMED carve-out ($428M EV) — leverage to flag for watch, but not an NPE signal.

Verify at: https://assignmentcenter.uspto.gov/ — search patent number 11,402,395 (mirror: https://assignment.uspto.gov/patent/index.html). Reel/frame and correspondent fields for the two events above should be confirmed there before any NPE inference; I could not retrieve them, so signals 3 and the exact reel/frame citations remain open.

I'll research US patent 11402395 and its cited prior art.

Let me get the complete list of cited references from the patent.

Let me get the exact reference list and claims for US11402395 specifically.

Prior-Art Analysis — US 11,402,395 B2

1. Patent identification (verified)

Because the effective filing date predates March 16, 2013, pre-AIA 35 U.S.C. § 102 governs. This matters for the analysis below:

• § 102(b) art must have been patented/published before Feb. 16, 2006 (one year before the priority date).
• References published between Feb. 16, 2006 and Feb. 16, 2007 can only be § 102(a)/(e) art.
• Any reference sharing the Feb. 16, 2007 priority chain is not prior art at all (it is the same family).

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2. Important methodological caveat

I was able to retrieve the patent's front‑page "References Cited" list (Google Patents, Justia) but could not open the USPTO PatentCenter/PAIR "References Cited" field for this exact document in this session. The list below is the reference list carried in this patent family (identical specification and examiner across the divisionals), which the Google Patents front page confirms for US 11,402,395 (it shows 3,817,837; 3,875,011; EP 0659751; EP 1470825, etc.). Treat the bibliographic citations as high‑confidence and the subject‑matter "descriptions" as confidence‑flagged: I mark ✔ where I am confident, ~ where I am reasonably confident, and ? where I could not verify the reference's content and will not guess.

Also note the key legal point up front: § 102 anticipation requires a single reference to disclose every element of a claim. The vast majority of the cited documents are generic immunoassay, antibody‑engineering, or unrelated gabapentin‑dosage‑form art. My bottom line, stated plainly: no cited reference appears to anticipate the compound claims or the method/antibody/kit claims of US 11,402,395; several support § 103 obviousness only.

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3. Most relevant prior art (ranked)

3.1 Closest art — gabapentin-derived small molecules (closest to claim 1)

3.2 Foundational immunoassay art (background to the method claims)

3.3 Antibody engineering / reagent art (background to the antibody and kit claims)

3.4 Applicant's own earlier family members — NOT prior art

The following are the applicant's own earlier patents/publications in the same Feb. 16, 2007 priority chain. Under pre‑AIA § 102 they cannot be prior art to this later division:

• US 8,168,756; US 8,828,665; US 8,841,136; US 9,522,880; US 10,203,345; US 11,231,424; US 11,525,835 B2 (all Valdez et al., ARK Diagnostics)
• Publications US 2008/0199887; US 2009/0093069; US 2010/0173427; US 2012/0190047; US 2014/0206020; US 2020/0400696 A1
• (US 11,402,395 itself is likewise listed among "References Cited" only as a self‑citation.)

3.5 Remaining cited U.S. publications and foreign documents

I list these for completeness. I could not verify their subject matter and therefore make no description or anticipation assertion: US 2005/0228035; US 2006/0115865; US 2006/0141548; US 2008/0009018; US 2011/0105448; US 2011/0212944. Foreign: WO 97/00248; WO 97/33858; WO 00/50027; WO 01/42191; WO 01/62726; WO 02/28883; WO 02/42414; WO 02/100344; WO 03/00642; WO 07/065036; WO 2008/097640; WO 2011/020605; WO 2012/172015.

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4. § 102 conclusion

• Compound claim 1 (and its dependent compound claims): no anticipation. No cited reference discloses a gabapentin core substituted at R¹/R²/R³ with the specific −X−W−L−Z chains recited (e.g., −NH−(CH₂)ₘ−SH, −NH−CO−(CH₂)ₙ−Br, −NH−(CH₂)ₒ−S−CH₂−CO−CH₂−Br, where m/n/o = 2 or 3). The XenoPort/Gallop/Cundy/Hui gabapentin‑derivative documents modify the molecule for transport/prodrug purposes, and the Rubenstein/Henderson/Salamone art is entirely silent on gabapentin. A § 102 rejection on any single one of these would fail the "arranged as in the claim" test.
• Method claims (detecting gabapentin via anti‑gabapentin antibody + gabapentin‑enzyme conjugate): no anticipation. Rubenstein '837/'011 and Henderson '929 supply the generic homogeneous‑enzyme‑immunoassay format but disclose no gabapentin hapten/conjugate/antibody → they can support § 103 only, not § 102.
• Antibody claims: no anticipation. Cabilly '567 and Marasco '829/'371 teach how to make antibodies/fragments but disclose no anti‑gabapentin antibody.
• Kit claims: no anticipation.
• Practical significance of the reference list: these citations were largely included to (i) show the immunoassay/hapten/antibody/conjugation techniques were known, and (ii) satisfy the applicant's duty of disclosure. They are an obviousness dossier, not an anticipation dossier. The claims survived because the combination — a gabapentin hapten bearing the recited reactive linker chemistry, coupled to G6PDH or KLH, used with an anti‑gabapentin antibody — was not found in any one reference.

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5. Limits of this analysis (stated explicitly)

1. I did not obtain the USPTO PatentCenter/PAIR IDS for US 11,402,395 itself; the list above is the family reference list, which the Google Patents front page corroborates but which I could not diff item‑by‑item against the '395 IDS.
2. For roughly twenty of the cited documents I could not verify the subject matter; I have marked those "?" and deliberately supplied no description and no anticipation assertion rather than guess.
3. Any conclusion on § 102 should be re‑run against the actual "References Cited" field in USPTO PatentCenter for application 17/478,639 and against the examiner's cited art, since I could not confirm each item in this session.

Primary sources: https://patents.google.com/patent/US11402395/en • https://patents.justia.com/patent/[11867705](/patent/11867705) (same‑family reference list) • US 11,402,395 B2 PDF (patentimages.storage.googleapis.com).

I'll gather the prior-art record for the '395 patent before analyzing. Let me run several searches in parallel.

Let me pull the patent's cited-art list and pre-2007 gabapentin immunoassay/derivative art.

Obviousness Analysis — U.S. Patent No. 11,402,395 (35 U.S.C. § 103)

0. Threshold caveats (read first)

A. What I actually had to work with. The message I received contained the full specification text of US 11,402,395 and the Google Patents bibliographic "Info" block, but not the enumerated "Citations / Cited By" table that normally appears on the Google Patents page. The only "Prior Art" fields present in the supplied material are:

• Prior art keywords: gabapentin, conjugate, antibody, compound, enzyme
• Prior art date: 2007-02-16

I searched to recover the missing citations table but the retrieved page content returned the same Info block and the "Cited By (19)" heading without the individual entries (https://patents.google.com/patent/US20080199887). So this analysis is built on (i) the references expressly cited or incorporated by reference inside the '395 specification itself — which are, functionally, the "documents considered" that an Examiner and a POSA would treat as the closest record — (ii) the same-family record (WO2008103319A2 / US2008/0199887 / US 8,828,665 / US 9,522,880 / US 10,203,345 / US 11,525,835 / US 11,867,705), and (iii) the gabapentin TDM literature named in the '395 Background. I flag this rather than pretend to have reviewed a citation table I did not receive.

B. I do not have verbatim claim text. The '395 front page states "17 Claims, 12 Drawing Sheets" (https://patentimages.storage.googleapis.com/64/4e/4a/0a0f57658e3e74/US11402395.pdf). The claim set itself was not in the supplied material. Claim scope below is therefore reconstructed from the specification's own "Features of the Invention" summary, which mirrors the claims. Verify against the actual claim set before relying on any mapping.

C. Priority is everything here. The '395 application (17/478,639) was filed 2021‑09‑17 but claims benefit of U.S. Provisional 60/890,313, filed Feb. 16, 2007 (https://www.patents-review.com/a/20220003793-compounds-methods-detecting-gabapentin.html). If that chain holds, the § 103 critical date is Feb. 16, 2007, and the entire ARK family — including WO2008103319 (published Aug. 28, 2008) and US 2008/0199887 — is co-priority and not prior art. If the chain breaks for any claim (no § 112 support in the 2007 provisional), the 2008 publication and the family patents instantly become § 102(a)(1)/(a)(2) art and the § 103 analysis below becomes almost academic. This is the single highest-value thing to check.

• Flag / contradiction: the '395 front page also carries "This patent is subject to a terminal disclaimer" — i.e., ODP over a co-priority family member (presumably the '665 or '345 patent) was already adjudicated at the USPTO. Terminal disclaimer does not create § 103 art against the '395, but it is evidence that the Office found these claims not patentably distinct from an earlier-expiring family member. Treat it as a signal, not as § 103 art (MPEP 804; In re Lonardo).
• Data discrepancy: Google Patents lists the family priority date as 2007‑02‑16; Unified Patents lists the sibling US 11,525,835 with "Priority Date: 2007-02-15" (https://portal.unifiedpatents.com/patents/patent/US-[11525835](/patent/11525835)-B2). These are inconsistent by one day and should be reconciled against the actual provisional filing receipt. Immaterial to the analysis, but it should not be silently harmonized.

D. POSA definition I am applying. A person of ordinary skill at Feb. 2007: an M.S./Ph.D. chemist or biochemist (or B.S. with 3–5+ years) with practical experience in hapten design, heterobifunctional crosslinking, protein conjugation, and immunoassay development (EMIT/CEDIA/FPIA-class formats). This is the level the '395 specification itself assumes — it cites the EMIT, CEDIA and FPIA patent literature as background knowledge, not as invention.

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1. What the claims cover (reconstructed)

The structural core — gabapentin with one of three attachment handles substituted — is the whole inventive contribution. There is no new chemistry in the '395: the conjugation reactions (bromoacetyl/SH, SATA thiolation, Sephadex purification) are the reactions of the cited art, applied to a newly DRUG-hapten.

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2. The prior-art record

2.1 Art the '395 itself cites (all pre‑2007)

2.2 Gabapentin-specific art the '395 itself relies on

The Background states the majority of gabapentin drug-level data came from LC and GC methods, citing Hengy & Kolle 1985; Ratnaraj & Patsalos 1998; Chollet et al. 2000; Wad & Kramer 1998; Ifa et al. 2001; Hooper et al. 1990; Kushnir et al. 1999, and then states: "While chromatographic techniques can be used to determine drug levels, such methods are impractical for commercial use due to… long sample preparation time, long assay time, high cost, and labor-intensive procedures. Immunoassays provide simple and fast analytical methods…"

That is the applicant's own admission of the motivation, placed in the patent by the applicant. It is the strongest single § 103 datum in the file: (a) gabapentin TDM was a recognized clinical need; (b) the existing methods were known to be commercially inadequate; (c) the POSA would look to immunoassay. What was missing was only the hapten and antibody — the routine part.

Adjacent art establishes the amine handle is derivatizable: gabapentin prodrug chemistry (e.g., XenoPort XP13512 / gabapentin enacarbil; Cundy et al., J. Pharmacol. Exp. Ther. 311:315‑323 (2004), which appears as PTX 269 in the Depomed/Actavis gabapentin litigation record) shows N‑acylation/carbamate formation at gabapentin's primary amine with linkers, and gabapentin's lactam formation is the classic intramolecular cyclization of that same amine onto the acid (cf. the Depomed record at https://storage.courtlistener.com/recap/gov.uscourts.njd.[271421](/patent/271421)/gov.uscourts.njd.271421.363.0.pdf).

2.3 Family / co-priority art (NOT § 103 art — know the difference)

WO2008103319A2 (2008‑08‑28), US 2008/0199887 (2008‑08‑21), US 8,828,665, US 9,522,880, US 10,203,345, US 11,525,835, US 11,867,705 — all share the Feb. 2007 priority and all disclose the same gabapentin derivatives, the same KLH conjugates, the same G6PDH conjugates and the same assay Examples (https://patents.google.com/patent/WO2008103319A2/en; https://www.freepatentsonline.com/y2008/0199887.html). They are not § 102/§ 103 prior art against the '395 if priority holds. They are, however:

• The ODP backdrop (terminal disclaimer on the '395 face);
• The instant killer if priority fails. Note in particular that US 2008/0199887 and WO2008103319 disclose the identical claimed subject matter, including the working conjugations (Examples 6–8: bromoacetylation of native G6PDH, SATA thiolation, gabapentin‑hapten coupling) and the rabbit polyclonal #10930. If any '395 claim is not supported by the 2007 provisional, the 2008 publication is § 102(a)(1) art and also § 103 art against everything.

2.4 What I could not verify

I did not confirm, in the searches run, a specific pre‑2007 reference disclosing a 4‑substituted gabapentin derivative (the Formula III / R3 genus — "extension from carbon 4 of gabapentin," compounds X–XIII, conjugates VI–VII). The general proposition that a POSA would vary the position remote from the pharmacophore is sound and is exactly the KSR "finite number of identified, predictable solutions" situation, but I would not represent that I have the reference in hand. This is where the '395 is most defensible, and where I would recommend a targeted pre‑2007 search (e.g., 4‑substituted gabapentin/cyclohexane-acetic-acid analogue art, and 4‑aminomethyl gabapentin work).

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3. Combinations that render the claims obvious

Combination 1 — The core compound + immunogen claims (Formulas I and II)

References: U.S. 3,817,837 (EMIT, hapten–enzyme conjugates) + the gabapentin TDM literature cited by the applicant (Hengy & Kolle 1985; Ratnaraj & Patsalos 1998; Hooper 1990; Kushnir 1999) + U.S. 5,439,798 (KLH thiolation) + U.S. 6,455,288 (bromoacetyl ↔ free-thiol coupling) + gabapentin's known structure (FIG. 1) and the known γ‑aminobutyric-acid-mimetic prodrug chemistry (Cundy 2004).

Motivation to combine — articulated, not hindsight:

1. Need: gabapentin has pronounced inter-individual PK variability and saturable absorption; TDM was a stated clinical goal (specification, Background).
2. Failure of the existing approach: LC/GC is slow, costly, and labor-intensive by the applicant's own characterization.
3. The known solution: immunoassay — the single accepted technique for routine TDM of small-molecule drugs. Immunoassay requires a hapten–carrier immunogen and an antibody; a drug of MW ≈ 171 cannot itself be immunogenic, so appending a linker and conjugating to KLH is the mandatory, mechanical first step of any hapten program.
4. The handles are not a design choice requiring invention: gabapentin has exactly two obvious, synthetically accessible functional handles — the primary amine and the carboxylic acid. The '395's own R1/R2/R3 genus is, at bottom, "derivatize at the amine, at the acid, or at the ring." Covering all available attachment points of a known small molecule is the paradigm of obviousness, not of invention (KSR 550 U.S. 398, 421 (2007); In re Rose, 220 F.2d 459 (CCPA 1955)).
5. The chemistry is pre-solved: bromoacetyl/3‑thiopropionyl heterobifunctional pairing and SATA thiolation were standard (U.S. 6,455,288; U.S. 5,439,798). Nothing in the '395 Examples deviates from those protocols.

Claim mapping: Formula I compounds (-NH-(CH2)m-SH; -NH-CO-(CH2)n-Br; -NH-(CH2)o-S-CH2-CO-CH2-Br; m,n,o = 2 or 3) and the corresponding Z = SH/Br dependents; the salts dependents (alkali metal/halide/acetate) are conventional salt selection. Formula II compounds (carboxyl-handle) follow identically from the second obvious handle.

Reasonable expectation of success: high. Hapten design at the amine vs. carboxyl of a small drug is routine and predictable; the '395 specification offers no data showing that any one linker/position was unpredictable.

Combination 2 — The enzyme-conjugate claims (including the G6PDH-cysteine limitation)

References: U.S. 6,455,288 + U.S. 6,033,890 + U.S. 6,090,567 + U.S. 3,817,837 + the Combination‑1 hapten.

Motivation: The '395 claims recite, essentially verbatim, the teaching of the '288/'890/'567 family — a G6PDH "comprising at least one cysteine per subunit… not native to a naturally-occurring G6PDH," coupled via bromoacetyl/thiol chemistry. The motivation is express: (a) G6PDH is the standard EMIT enzyme because its activity is readily modulated by antibody binding near the active site; (b) the '288 family identifies the known problem with native cysteine coupling — loss of enzyme activity and heterogeneous conjugate mixtures — and solves it by site-directed introduction of a single non-native cysteine, which improves conjugation control and preserves activity; (c) a POSA optimizing a gabapentin EMIT would adopt that solution as a matter of routine optimization. Indeed the '395 specification directs the reader to these very patents for determining cross-reactivity "in the same type of immunoassay in which the antibody will ultimately be used."

Claim mapping: the "G6PDH" dependents; the "detectable label comprises an enzyme / dehydrogenase / G6PDH" method dependents; the "enzyme is selected from alkaline phosphatase, β-galactosidase, horseradish peroxidase" genus (all conventional label choices per U.S. 4,708,929 and the FPIA/CEDIA art).

Strength of case: Strong. This is the combination with the least daylight between the reference disclosure and the claim language. The only arguable gap is the identity of the hapten — and Combination 1 closes it.

Combination 3 — The method claims

References: any one of U.S. 3,817,837 / 4,708,929 / the FPIA patents + an anti-gabapentin antibody raised against the Combination‑1 immunogen + a gabapentin calibration standard.

Motivation: Once the immunogen and the drug–label conjugate exist, the assay format is a selection among known, fully described formats (homogeneous EMIT, CEDIA, FPIA, heterogeneous ELISA/RIA/CMIA, lateral flow — each expressly recited in the '395 as known art). The '395's own language — "the invention also encompasses the use of these materials in lateral flow chromatography technologies," "CMIA can also be used," "the FPIA reagents, systems, and equipment described in the incorporated references can be used" — is a catalogue of conventional formats, i.e., an admission that format selection is not the invention. The claims' "quantitative" and "measuring the amount" dependents are the express purpose of EMIT-type assays.

Expectation of success: routine optimization of antibody dilution, conjugate load, and buffer, with no unpredictable element identified.

Combination 4 — The antibody claims

References: Combination‑1 immunogen + Kohler & Milstein (1975) and/or U.S. 4,491,632 / 4,472,500 / 4,444,887 / 4,816,567 / 5,851,829 / 5,965,371.

Motivation: generating polyclonal and monoclonal antibodies against a KLH–hapten immunogen is the textbook next step; the '395's own Examples use Freund's adjuvant, rabbit immunization, and serum screening against a gabapentin–protein conjugate — entirely conventional. Fab/F(ab′)₂/Fv/scFv dependents are recited as known fragments/fragment formats.

Countervailing point (for completeness): claims to an antibody defined only by its binding specificity ("specifically binds gabapentin") as a genus may face a distinct § 112 written-description/enablement problem, and practitioners sometimes argue that antibody generation is unpredictable. But where the antigen is known and the immunogen is routine, "obvious to try" reasoning generally carries the day on § 103. I would rate the enablement attack at least as strong as the § 103 attack on these claims — but that is a § 112 issue, outside this task.

Combination 5 — The kit claims

References: Combination‑3 components + the art of immunoassay reagent kits (buffers, stabilizers, solid supports, instructions).

Motivation: "kit comprising antibody + calibration standard (+ enzyme conjugate + substrate)" is the standard commercial packaging of a homogeneous enzyme immunoassay. The specification itself describes it as conventional (lyophilized or liquid, separate or combined containers, indicator cartridges).

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4. Reasons the claims could nonetheless survive (§ 103 defenses to anticipate)

1. Priority defeats the best art. If the Feb. 16, 2007 chain is intact, the closest and most damaging references — WO2008103319 and US 2008/0199887, which disclose the same compounds, conjugates, and assay — are co-priority and cannot be prior art. An attacker must either break priority or find genuinely independent pre‑2007 gabapentin-hapten art. On the record I could obtain, no independent pre‑2007 gabapentin hapten/immunogen reference is confirmed. That is the strongest defensive position in this file.
2. The generic platform art does not disclose gabapentin. The EMIT/CEDIA/FPIA and antibody-generation references teach formats, not the gabapentin hapten. A petitioner must supply the missing § 103 link — a reason a POSA would derivatize gabapentin at a particular position with a particular linker. The R1/R2/R3 omnibus genus makes that link easy to argue, but the species-level claims (specific compounds I–XIV) and the C4 (Formula III) family are the harder targets.
3. Terminal disclaimer ≠ § 103 art. The ODP finding that likely produced the terminal disclaimer on the '395 face is evidence of near-identity to a family member, but ODP and § 103 are separate doctrines (In re Lonardo), and the family member is not § 103 art if co-priority. Do not let the "terminal disclaimer" fact be over-read as an obviousness holding.
4. Unexpected results (weak as presently framed). The specification reports a calibration curve (FIG. 6) and rabbit antiserum #10930 with screening for "curve size" and cross-reactivity. To rebut § 103, the patentee would need comparative data — e.g., that the amine-linked hapten unexpectedly outperforms the carboxyl-linked hapten, or that the C4-linked hapten gives a cross-reactivity profile against gabapentin lactam / pregabalin that could not have been predicted. As pleaded, the specification shows a working assay, not an unexpected result. Absent such data, the "unexpected results" argument is likely to fail.

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5. Bottom line

Most probable § 103 combination asserted by a challenger: U.S. 6,455,288 (bromoacetyl/thiol conjugation + G6PDH cysteine variants) in view of U.S. 3,817,837 (EMIT) and U.S. 5,439,798 (KLH thiolation), further in view of gabapentin's known structure and the gabapentin-TDM literature cited in the '395 Background.

The three things that would change the answer:

1. The actual claim set and the Google Patents Citations/Cited-By table for the '395 (neither was in the material I received).
2. Whether the Feb. 16, 2007 priority chain is intact claim-by-claim. If broken, WO2008103319 / US 2008/0199887 alone anticipate or render obvious nearly everything.
3. Confirmation of any pre‑2007 reference disclosing a gabapentin immunogen/hapten — which would remove the last remaining gap in Combination 1.

Note on the earlier section: the litigation summary concluded no case names the '395 patent, and that the ARK enforcement campaign (ITC Inv. 337‑TA‑1239; C.D. Cal. 5:21‑cv‑00871) asserted only the '665 and '345 patents. That is consistent with the priority/ODP picture above — the '345 is a co-priority family member that issued in 2019, well before the '395 issued on Aug. 2, 2022 — and it reinforces that the family, not the '395 individually, has been the enforcement vehicle. I found nothing in this task's research that contradicts the litigation section.