Untitled case

This Post-Grant Review (PGR) proceeding, PGR2026-00023, is currently pending before the Patent Trial and Appeal Board (PTAB) of the U.S. Patent and Trademark Office. The Petitioner, Viance, LLC, filed the petition on March 17, 2026, challenging the validity of U.S. Patent 12,370,716. The Patent Owner is Koppers Performance Chemicals, Inc.

Viance, LLC is an industry leader in developing advanced treated wood and utility pole protection solutions, specializing in wood biocides and protection chemicals for residential, commercial, and industrial applications. Koppers Performance Chemicals, Inc. is also a global leader in wood preservation technology, developing innovative ways to pressure treat lumber for various uses, including residential construction, commercial building, marine, agricultural, and industrial applications, and providing essential products for utility companies. This suggests a competitive dispute within the wood treatment and preservation industry.

The patent at issue, U.S. Patent 12,370,716, titled "Wood Preservative Composition," generally describes wood preservative compositions, specifically concentrates, that contain high concentrations (40-60% by weight) of 4,5-dichloro-2-octylisothiazol-3-one (DCOI) and a wax-based "retaining additive." The stated purpose of this retaining additive is to reduce the leaching of the DCOI preservative from treated wood. Viance's challenge in this PGR focuses on the assertion that the '716 patent lacks written description support in its provisional application for these high concentration ranges of DCOI and retaining additive. This alleged lack of priority would make intervening prior art, such as a publication by Archer (WO 2023/096905), available to challenge claims 1-5 and 7-27 for anticipation or obviousness.

This case is notable as it is a Post-Grant Review, a type of PTAB proceeding less frequently filed than Inter Partes Reviews (IPRs). PGRs allow for a broader range of invalidity grounds to be asserted (including §§ 101, 102, 103, and 112 grounds, excluding best mode), and can utilize prior art beyond just patents and printed publications. However, PGRs also carry a broader estoppel effect compared to IPRs, potentially preventing the petitioner from raising any ground that was raised or reasonably could have been raised in a subsequent district court or ITC proceeding. The PTAB provides a specialized forum with technically trained judges and a faster resolution timeline compared to district court litigation, often at a lower cost. The specific challenge regarding written description and the impact of priority on prior art availability highlights a significant legal dispute over the patent's foundational validity.

Key Legal Developments and Outcome

This PGR proceeding, PGR2026-00023, is currently pending before the Patent Trial and Appeal Board (PTAB). The Petitioner, VIANCE, LLC, filed its petition on March 17, 2026, challenging US Patent 12370716. The Patent Owner is Koppers Performance Chemicals, Inc.

Viance, LLC is a company that provides advanced wood treatment technologies and services, specializing in wood biocides and protection chemicals. They have a history of developing DCOI-based preservatives, launching products like Ecolife® and UltraTie with DCOI. Kevin Archer, Viance's Director of Research and Development, has worked for the company since 2007 and was involved in the development of the UP-50 product, which is relevant to the PGR.

The '716 patent, titled "Wood Preservative Composition," generally describes wood preservative compositions, particularly concentrates, containing high concentrations (40-60% by weight) of 4,5-dichloro-2-octylisothiazol-3-one (DCOI) and a wax-based "retaining additive" to reduce DCOI leaching from treated wood.

Filing & Initial Pleadings

• PGR Petition Filing (2026-03-17): VIANCE, LLC filed the petition for Post-Grant Review against US Patent 12370716. The petition challenges claims 1-27 of the '716 patent.

  • Grounds for Unpatentability: Viance's challenge centers on the assertion that the '716 patent is not entitled to the filing date of its provisional application. This alleged lack of priority would make intervening publications and on-sale activities available as prior art.
    • Ground 1 (Anticipation or Obviousness over Archer): Petitioner argues that claims 1-5 and 7-27 are anticipated or rendered obvious by Archer (WO 2023/096905), an intervening prior art publication. Archer's Example 6 reportedly discloses a concentrate composition of "50% DCOI and 50% wax," falling within the claimed ranges of the '716 patent.
    • Ground 2 (On-Sale Bar based on UP-50 product): Petitioner argues that its own "UP-50" product was subject to a commercial offer for sale in a Business Development and Exclusive Supply Agreement (BDES Agreement) dated February 5, 2021, and was commercially sold before the '716 patent's effective filing date. The UP-50 product is described as a wood preservative concentrate with 50% by weight DCOI and 50% by weight of a wax blend.

• Notice of Filing Date Accorded (2026-03-19): The PTAB issued a notice confirming the filing date of March 17, 2026, for the petition. This notice also informed the Patent Owner, Koppers Performance Chemicals, Inc., of the deadlines for filing a brief requesting discretionary denial (within two months) and a preliminary response (no later than three months from the notice date). The Patent Owner must also submit mandatory notice information within 21 days of service of the petition, including identifying any other judicial or administrative matter that would affect the proceeding.

Parallel PTAB IPR/PGR Proceedings

There is no information available from the provided search results about parallel district court litigation involving US Patent 12370716. The PGR itself is a parallel PTAB proceeding to any potential infringement litigation.

Recent PTAB developments indicate that PGR petitions are in a "favored" position for institution compared to IPRs, especially when parallel district court litigation exists. This is because PGRs must be filed within nine months of the patent grant, placing them closer to the examination process before patent rights are strongly settled.

As of October 20, 2025, the USPTO Director, in consultation with at least three PTAB judges, is responsible for deciding whether to institute IPR and PGR trials. These institution decisions now generally provide only a summary notice of grant or denial, with more detailed decisions reserved for cases with novel or important factual or legal issues.

Viance, LLC, the Petitioner in PGR2026-00023, is represented by the following counsel from McAndrews Held and Malloy Ltd.:

• Thomas J. Wimbiscus

  • Role: Lead Counsel
  • Firm: McAndrews Held and Malloy Ltd., Chicago, IL
  • Experience: Has over thirty years of experience in intellectual property litigation, with a strong emphasis on patent and trademark disputes, and has appeared in over 100 litigations and 100 inter partes reviews (IPRs). He was named one of the 10 most active IPR practitioners for patent owners.

• Priscilla F. Gallagher

  • Role: Backup Counsel
  • Firm: McAndrews Held and Malloy Ltd., Chicago, IL
  • Experience: Has over 30 years of experience in intellectual property practice, specializing in developing global patent portfolios, patent analysis, and patent prosecution across various technical arts, and has been a member of several successful litigation teams.

• Scott McBride

  • Role: Backup Counsel
  • Firm: McAndrews Held and Malloy Ltd., Chicago, IL
  • Experience: A nationally recognized trial lawyer who specializes in patent infringement and complex technology cases in federal courts, the ITC, and before the Patent Trial and Appeal Board. He has secured one of the largest patent damages awards in U.S. history.

I'll research counsel of record for the Patent Owner (the respondent/defendant-side party) in PGR2026-00023, and check for any parallel district court litigation where Koppers is the plaintiff.

Key finding already: the case status in the metadata appears outdated — the Director denied institution on Aug 19, 2026. Let me dig into the Patent Owner's counsel and any parallel district court case.

Robert R. Riddle of Reed Smith (Houston) appears as respondent counsel. Let me verify against the PTAB docket and check for a parallel district court case.

Threshold point: there is no "defendant" in this case

Before naming anyone, a framing correction is required. PGR2026-00023 is not a patent infringement case. It is a post-grant review before the PTAB. There is no plaintiff, no defendant, and no district court docket to pull. The adversarial parties are:

• Petitioner / challenger: Viance, LLC (represented by McAndrews, Held & Malloy — already covered in the prior section)
• Patent Owner / respondent (the functional "defense" side): Koppers Performance Chemicals, Inc.

So the answer to "counsel representing the defendant(s)" is: counsel of record for Patent Owner Koppers Performance Chemicals, Inc., the respondent.

⚠️ Contradiction with the case metadata — please flag

The metadata and the prior sections describe the case as "Pending." Search results indicate that is outdated and materially wrong:

• On August 6, 2026, USPTO Director John Squires issued a Notice indicating denial of institution.
• On August 19, 2026, the Director denied institution of the PGR. The sole ground was that Viance failed to name its 50.001% owner, Venator, as a real party in interest, and the omission was uncurable because amendment would push the petition outside PGR's nine-month window. Multiple third-party databases (Law360, GreyB/IPVerse, Ex Parte AI Lab) now list the status as "Discretionary Denial" with a termination date in August 2026.

Reporting on the decision (Stradling client alert; JD Supra; Law360) confirms Koppers prevailed on the RPI argument, relying on Corning Optical v. PPC Broadband, IPR2014-00440, Paper 68, and Tianma v. LG Display, IPR2025-01579, Paper 12, with the Director applying his own Sun Pharmaceutical v. Biofrontera, PGR2026-00021, Paper 12 (May 26, 2026) precedent. The Director left open that Viance may refile as an IPR naming Venator and Lanxess without repeat-challenge penalty. I did not find that a follow-on IPR has been filed. The prior sections' account of the petition grounds (Archer WO 2023/096905, the UP-50 on-sale bar, the BDES Agreement) remains accurate as a description of what was argued, but the proceeding never reached the merits.

Counsel of record for the Patent Owner (Koppers Performance Chemicals, Inc.)

Source for the identification: GreyB/IPVerse PTAB case record for PGR2026-00023 lists "Respondent Counsel — Riddle, Robert et al." (ipverse.greyb.com); corroborated by Chambers and Reed Smith's firm bio. Riddle's PTAB practice for patent owners is independently documented — e.g., he filed the Patent Owner Power of Attorney as lead counsel for BASF Corporation in a BASF IPR (USPTO PTACTS document, Reg. No. 69,599, Reed Smith Houston).

What I could not verify — stated explicitly rather than guessed

• The full counsel roster. Papers 5 (Patent Owner Power of Attorney) and 6 (Patent Owner Mandatory Notice), filed March 25 and April 1, 2026, are the operative documents naming every practitioner. I could not retrieve their full text; the "et al." in the aggregator is not a complete list. Do not treat the table above as the complete team.
• Any local counsel or in-house counsel. No Pittsburgh-based Reed Smith practitioner, no Koppers legal-department attorney, and no separate local counsel is confirmable from available sources. Koppers, Inc. is headquartered in Pittsburgh, so Pittsburgh-office involvement is plausible but I found no evidence of it and will not assert it.
• Whether Reed Smith is still counsel post-termination. With the proceeding terminated, the power of attorney is of diminished practical effect; any residual dispute would be in a different forum.

On parallel district court litigation

No district court infringement action involving U.S. Patent 12,370,716 was located. There is no PACER docket, no complaint, no Law360/Reuters coverage of a Koppers v. Viance suit. If such a case exists, it is either unindexed in the sources I could reach or filed under seal — but nothing in the record supports its existence.

Note the strategic posture this creates: the PGR was plainly a pre-emptive strike by the accused/competing party (Viance's own UP-50 product and BDES Agreement were the on-sale-bar exhibits, Exs. 1012–1014, 1027, 1031–1035), with no co-pending litigation forcing the challenge. That cuts both ways — it removed any Fintiv-style discretionary-denial pressure, but it also meant the Director had no countervailing reason to overlook the RPI defect. Had Koppers sued Viance, Viance's defense counsel in that suit would presumably have been the McAndrews team already profiled; that is an inference, not a sourced fact.