Invalidity dossier

US 9233167

Oligomer-opioid agonist conjugates

Current assignee: Nektar Therapeutics

Added 9/21/2026, 12:39:59 PM

At a glanceNo PTAB challengesNo litigation on file

Active provider: DeepSeek · deepseek-flash

Patent summary

Title, assignee, inventors, filing/issue dates, abstract, and a plain-language overview of the claims.

✓ Generated

Patent Overview — US 9,233,167 B2

Title: Oligomer-opioid agonist conjugates
Patent number: US9233167B2
Application number: US14/581,721
Inventor(s): Jennifer Riggs-Sauthier, Bo-Liang Deng, Timothy A. Riley
Original assignee: Nektar Therapeutics
Current assignee (as listed): Nektar Therapeutics
Priority date: 2007-03-12 (claimed from PCT/US2008/003353, WO2008112288A2)
Filing date: 2014-12-23
Publication date: 2016-01-12
Anticipated expiration: 2028-03-12
Legal status (as listed): Active

Purpose and plain-language scope. The supplied text identifies the invention as "oligomer-opioid agonist conjugates." The recurring prior-art keywords — "mPEG," "PEG," "oligomer," "conjugates," and "nalbuphine" — indicate that the disclosed subject matter concerns attaching an oligomer (notably a PEG/mPEG-type water-soluble oligomer) to an opioid agonist compound. Consistent with that, the chemical structures appearing in the excerpt include nalbuphine (and related structures bearing a cyclobutylmethyl substituent) linked via a methoxy-PEG-type moiety — for example, the compound indexed as COCCOC1=C2O[C@H]3C@@HCC[C@@]4(O)[C@H]5CC(=C2[C@@]34CCN5CC2CCC2)C=C1. So, in plain terms, the patent appears directed to opioid agonist drugs modified by covalent attachment of a short PEG/oligomer chain, likely to alter their pharmaceutical behavior. The excerpt also shows synthetic schemes for preparing such conjugates (including mPEG chloride reagents and nalbuphine starting material), but it does not state any express utility, dosage, or therapeutic indication.

Source URL: https://patents.google.com/patent/US9233167/en

What the excerpt does not establish. The provided text contains only bibliographic data, assignment/legal-status entries, and chemical structures/names. It does not include the claims, written description, examples, or assay data. Accordingly, the excerpt does not establish the actual claim scope, the full set of opioid agonists or oligomers covered, the linker chemistry definitions, any asserted utility or clinical use, enablement, or the interpretation of any claim term. The stated legal status is expressly an assumption, not a legal conclusion. No determination regarding validity, enforceability, or prior art is made here.

Generated 10/1/2026, 10:01:01 PM

Cases on file (0)

Specific litigation cases in our database that name US patent 9233167. The free-form analysis below may also discuss cases beyond this list.

No cases on file mention this patent. Upload a CSV or add a case manually in Admin → Manage litigation cases.

Litigation summary

Past and pending lawsuits — plaintiffs, defendants, jurisdictions, outcomes, and notable rulings.

Log in to generate
Not generated yet. Log in to request this analysis.

Proceedings on file (0)

All PTAB activity →

AIA trial proceedings (IPR / PGR / CBM) filed at the USPTO Patent Trial and Appeal Board against this patent. Sourced from the USPTO Open Data Portal and refreshed every six hours; each proceeding number deep-links to the PTAB E2E docket.

No PTAB proceedings on file. This patent has not been challenged via IPR, PGR, or CBM. The absence is itself a signal — well-asserted patents eventually attract IPRs. The LLM analysis below may surface filings the ODP feed hasn’t indexed yet.

PTAB challenges

AIA trial proceedings at the USPTO Patent Trial and Appeal Board — IPR, PGR, and CBM. Petitioners, judge panels, claim-level invalidation outcomes from Final Written Decisions, and Federal Circuit appeals. The single most important defensive datapoint after litigation history.

Log in to generate
Not generated yet. Log in to request this analysis.

Assignment history

Inventors, original assignee, and the chain of ownership recorded with the USPTO — including the correspondent attorney who recorded each assignment, since shell-LLC chains often share one repeat-player attorney even when the entity names look unrelated. Surfaces NPE / patent-troll patterns: shell-entity transfers, known asserters in the chain, repeat correspondent fingerprints, pre-litigation assignments, and bankruptcy fire-sales.

Log in to generate
Not generated yet. Log in to request this analysis.

Prior art

Earlier patents, publications, and products that may anticipate or render the claims unpatentable.

Log in to generate
Not generated yet. Log in to request this analysis.

Obviousness

Combinations of prior art that suggest the claimed invention would have been obvious under 35 U.S.C. § 103.

Log in to generate
Not generated yet. Log in to request this analysis.

Extensions

Patent term adjustments, term extensions, continuations, divisionals, family members, and expiration dates.

Log in to generate
Not generated yet. Log in to request this analysis.

Derivative works

Defensive disclosure: derivative variations of each claim designed to render future incremental improvements obvious or non-novel.

Log in to generate
Not generated yet. Log in to request this analysis.