Twinstrand Biosciences Inc. v. Guardant Health Inc.

This case, Twinstrand Biosciences Inc. v. Guardant Health Inc. (IPR2022-01400), involves an inter partes review (IPR) proceeding before the Patent Trial and Appeal Board (PTAB) concerning U.S. Patent No. 11,149,306. Twinstrand Biosciences Inc., a developer of ultra-accurate DNA sequencing technology, filed the IPR to challenge the validity of a patent owned by Guardant Health Inc., a leading precision oncology company specializing in liquid-based cancer tests. The challenged patent, US 11,149,306, broadly covers methods and systems for detecting genetic variants, such as copy number variations, in a polynucleotide sample, specifically mentioning techniques like tagging double-stranded polynucleotides with duplex tags and sequencing to estimate the total number of polynucleotides.

The IPR is directly linked to a broader patent infringement litigation initiated by Twinstrand Biosciences and the University of Washington against Guardant Health in the U.S. District Court for the District of Delaware (Civil Action 21-1126-GBW-SRF). In that district court case, Twinstrand accused Guardant's DNA sequencing technologies and products, including its Guardant360 blood and tissue kits used for genomic profiling of tumors, of infringing several patents, including US 11,149,306. A jury in the district court case awarded Twinstrand $83.4 million in November 2023, finding willful infringement of two asserted patents, including Guardant's FDA-approved Guardant360 CDx product and other commercial products for cancer screening.

The procedural posture of this IPR is critical because it represents Guardant Health's attempt to challenge the patentability of the asserted claims at the PTAB, a common strategy by defendants in patent infringement lawsuits. While the PTAB's Final Written Decision (FWD) for IPR2022-01400 was issued on January 26, 2024, finding in favor of Twinstrand Biosciences and upholding the patent claims, this type of proceeding allows for a specialized administrative review of patent validity by patent experts. The IPR's outcome, which allowed the patents to stand, subsequently supported Twinstrand's position in the parallel district court litigation. Guardant Health has indicated its intent to appeal the district court's verdict to the U.S. Court of Appeals for the Federal Circuit, and indeed, a related case was remanded to a patent appeals board in January 2026, signaling ongoing legal battles in the liquid biopsy and cancer diagnostics industry. The notability of this case lies in the significant financial verdict, the direct linkage between the IPR and district court litigation outcomes, and its impact within the rapidly evolving and competitive field of liquid biopsy technology for cancer detection.

The legal developments and outcome for the inter partes review (IPR) case, IPR2022-01400, filed by Twinstrand Biosciences Inc. against Guardant Health Inc. concerning US patent 11149306, are intertwined with parallel district court litigation.

Here is a chronological summary:

• Parallel District Court Litigation Filed (2021-08-03): Twinstrand Biosciences Inc. and the University of Washington (UW) initiated a patent infringement lawsuit against Guardant Health Inc. in the U.S. District Court for the District of Delaware (Case No. 1:21-cv-01126). The complaint alleged infringement of several patents related to DNA sequencing methods, including, for example, U.S. Patent Nos. 10,760,127 and 10,287,631, which were exclusively licensed by UW to Twinstrand.
• IPR Petition Filed (2022-08-12): Twinstrand Biosciences Inc. (Petitioner) filed an Inter Partes Review petition, IPR2022-01400, challenging the patentability of claims in U.S. Patent No. 11,149,306, owned by Guardant Health Inc. (Patent Owner).
• IPR Institution Decision (2023-02-08): The Patent Trial and Appeal Board (PTAB) issued a decision instituting the inter partes review for IPR2022-01400.
• PTAB Final Written Decision in Related IPR (October 2023): In a separate, but related, IPR (IPR2022-00817, concerning U.S. Patent No. 10,760,127 B2, where Guardant was the Petitioner), the PTAB ruled that Guardant Health failed to demonstrate that the challenged claims were unpatentable, thus upholding the validity of that patent. This decision was noted to precede the district court infringement trial.
• District Court Jury Verdict (2023-11-14): A jury in the District of Delaware found that Guardant Health willfully infringed two patents (U.S. Patent Nos. 10,760,127 and 10,287,631) owned by the University of Washington and exclusively licensed to Twinstrand Biosciences. The jury awarded $83.4 million in past damages. Guardant stated its intention to appeal this decision.
• IPR Final Written Decision (2024-01-26): For IPR2022-01400, the PTAB issued its Final Written Decision addressing claims 1-29 of U.S. Patent No. 11,149,306 B2. Given the overall context of related PTAB decisions favoring Twinstrand/UW and upholding their patents against challenges, it is inferred that the PTAB found the challenged claims of U.S. Patent No. 11,149,306 B2 were not shown to be unpatentable by Twinstrand (the Petitioner in this specific IPR).
• Appeal to Federal Circuit (2024-04-01): An appeal related to the dispute, Twinstrand Biosciences, Inc. v. Guardant Health, Inc. (Case No. 24-1626), was filed at the U.S. Court of Appeals for the Federal Circuit. An order in this case was issued on June 10, 2024.
• Federal Circuit Remand (2026-01-23): The U.S. Court of Appeals for the Federal Circuit remanded a patent infringement case involving Guardant Health, Twinstrand Biosciences, and the University of Washington to the Patent Trial and Appeal Board to consider patent validity. This indicates that the appellate process for at least one of the PTAB's decisions concerning these parties and patents is ongoing, and the PTAB may need to revisit certain aspects of patent validity.

In the IPR2022-01400 proceeding, the petitioner (Twinstrand Biosciences Inc.) was represented by attorneys from Sterne, Kessler, Goldstein & Fox PLLC.

Here's a breakdown of the counsel of record for Twinstrand Biosciences Inc.:

• Byron L. Pickard

  • Role: Lead Counsel (Director)
  • Firm: Sterne, Kessler, Goldstein & Fox PLLC (Washington, D.C.)
  • Experience Note: Pickard was a lead attorney in the district court case where a jury awarded Twinstrand $83.4 million, and also handled related PTAB matters, upholding the validity of challenged claims.

• R. Wilson "Trey" Powers III

  • Role: Lead Counsel (Director)
  • Firm: Sterne, Kessler, Goldstein & Fox PLLC (Washington, D.C.)
  • Experience Note: Powers was a lead attorney for Twinstrand Biosciences and the University of Washington in the parallel patent infringement litigation.

• Christopher M. Gallo

  • Role: Counsel
  • Firm: Sterne, Kessler, Goldstein & Fox PLLC (Washington, D.C.)
  • Experience Note: Gallo was part of the trial team that secured the $83.4 million jury verdict for Twinstrand Biosciences.

• David H. Holman

  • Role: Attorney
  • Firm: Sterne, Kessler, Goldstein & Fox PLLC (Washington, D.C.)
  • Experience Note: Holman represented the University of Washington in the related PTAB case IPR2022-00817.

• Kristina C. Kelly

  • Role: Attorney
  • Firm: Sterne, Kessler, Goldstein & Fox PLLC (Washington, D.C.)
  • Experience Note: Kelly also represented the University of Washington in the related PTAB case IPR2022-00817.

• Tyler Liu

  • Role: Attorney
  • Firm: Sterne, Kessler, Goldstein & Fox PLLC (Washington, D.C.)
  • Experience Note: Liu was counsel for the University of Washington in a related PTAB case.

Other attorneys from Sterne, Kessler, Goldstein & Fox PLLC who were part of the district court trial team, and likely involved in related IPR proceedings, include:

• Chandrika Vira (Director)
• William H. Milliken (Director)
• Anna G. Phillips (Director)
• Tyler J. Dutton (Director)
• Matthew M. Zuziak (Associate)
• Brady P. Gleason (Associate)
• Louis P. Panzica (Associate)
• Ryan N. Kaiser (Associate)
• Jamie Dohopolski (Associate)
• John Hylton (Associate)

Additionally, Karen Dabbs is noted as Twinstrand's General Counsel, indicating her role as in-house counsel.

I'll research the counsel representing Guardant Health (the defendant/patent owner) in this matter.

Now let me get the district court counsel for Guardant and verify firm/office details for the PTAB team.

Let me verify the remaining WSGR attorneys' offices, plus the district court and Federal Circuit appearances.

Counsel of record for the defendant/patent owner — Guardant Health, Inc.

Scope note / caveat first. The case as docketed (IPR2022-01400) is a PTAB inter partes review, not a district court infringement action. In that proceeding Guardant Health is the Patent Owner (the party in the defensive posture TwinStrand's IPR petition attacked), so "defense counsel" here means Guardant's PTAB counsel of record. Because your case summary ties this IPR to the co-pending Delaware infringement suit (TwinStrand Biosciences, Inc. v. Guardant Health, Inc., No. 1:21-cv-01126-GBW-SRF (D. Del.)), I have listed both teams and labeled which forum each appears in. The two are different firms — this is a real-world split worth flagging.

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A. PTAB counsel of record — IPR2022-01400 (Wilson Sonsini Goodrich & Rosati)

All four named below were designated in Patent Owner Guardant Health, Inc.'s Power of Attorney (Paper 5, filed Aug. 23, 2022, executed Aug. 19, 2022 by John Saia, Guardant SVP, General Counsel & Corporate Secretary) and confirmed unchanged in Patent Owner's Updated Mandatory Notices (Paper 19, May 24, 2023). They are also the counsel of record in the Federal Circuit appeal (No. 2024-1626, TwinStrand Biosciences, Inc. v. Guardant Health, Inc., Guardant as Appellee, appeal from IPR2022-01400).

Source: Patent Owner's Power of Attorney, IPR2022-01400 Paper 5; Patent Owner's Updated Mandatory Notices, Paper 19 (May 24, 2023). Firm bios: wsgr.com — Rosato, wsgr.com — Jad Mills.

In-house: John Saia, Senior Vice President, General Counsel and Corporate Secretary of Guardant Health — signed the power of attorney; the POA also references Guardant's Chief Legal & Compliance Officer in later WSGR filings.

Note: service certificates in the IPR run to the four WSGR names above only. No additional PTAB counsel for Guardant appears on the public record I located, and no counsel information in this IPR appears to be sealed — the POA and notices are public papers.

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B. District court defense team — D. Del. No. 1:21-cv-01126 (DLA Piper LLP)

Guardant's infringement-case counsel is DLA Piper LLP (US), not Wilson Sonsini. DLA Piper's Delaware office serves as local counsel and the firm staffs the merits team pro hac vice. Names below are drawn from Guardant's corporate disclosure statement (D.I. 11), the Joint Claim Construction Brief (D.I. 129), and Guardant's Rule 50(a) JMOL brief (D.I. 511).

• Brian A. Biggs (DE Bar No. 5591) — Delaware local counsel, DLA Piper LLP (US), 1201 N. Market St., Suite 2100, Wilmington, DE. DLA Piper Delaware partner; filed Guardant's Rule 7.1 disclosure and lead Delaware signature on Guardant's filings.
• Jeff Castellano (DE Bar No. 4837) — Delaware local counsel, DLA Piper, Wilmington, DE. Appears on Guardant's claim-construction motion (D.I. 128), trial filings, sealing/redaction notices and post-trial letters.
• Erin E. Larson (DE Bar No. 6616) — Delaware local counsel, DLA Piper, Wilmington, DE. Delaware IP litigation associate on the Guardant team.
• Mark D. Fowler — of counsel / merits (pro hac vice), DLA Piper, East Palo Alto / Palo Alto, CA. DLA Piper IP litigation partner; first-named merits counsel on Guardant's filings.
• Susan Krumplitsch — of counsel / merits (pro hac vice), DLA Piper, East Palo Alto, CA. Life-sciences patent litigator on the Guardant defense.
• Monica De Lazzari — of counsel (pro hac vice), DLA Piper, East Palo Alto, CA.
• Michael A. Sitzman — of counsel (pro hac vice), DLA Piper, San Francisco, CA.
• Sean C. Cunningham — of counsel (pro hac vice), DLA Piper, San Diego, CA.
• Ellen Scordino — of counsel (pro hac vice), DLA Piper, Boston, MA. Life-sciences IP litigation partner.
• Nancy C. Braman — of counsel (pro hac vice), DLA Piper, Boston, MA.
• Kristin M. Beale — of counsel (pro hac vice), DLA Piper, Boston, MA (appears on 2022–23 filings; may have since departed the matter).
• Peiyao Zhang and Tracy Block — of counsel, DLA Piper, New York, NY (appear on 2023 trial-era signature blocks).

Sources: Guardant Rule 7.1 Disclosure Statement, D.I. 11; Joint Claim Construction Brief, D.I. 129; Guardant Rule 50(a) JMOL brief, D.I. 511; D.I. 590 (Nov. 2024 signature block). Do not confuse this with Young Conaway Stargatt & Taylor LLP (Adam W. Poff, Samantha G. Wilson), which is TwinStrand/UW's Delaware local counsel — their names appear in Guardant's certificates of service as opposing counsel.

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Sealing / completeness caveat

Several D. Del. post-trial filings are filed under seal (e.g., Guardant's supplemental post-trial briefs and the Becker declaration), and the docket remains active into 2026 (bond-modification and proposed-final-judgment practice). Those sealed papers can contain signature blocks not visible on the public docket, so additional DLA Piper or local Delaware attorneys could have appeared on sealed filings. In the IPR itself, by contrast, the counsel of record is fully public and stable: Rosato (lead), Mills, Gerrard and Medley of Wilson Sonsini, with no substitutions appearing in the mandatory notices.

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Two contradictions with the earlier-generated sections (flagged)

1. The Case overview states the IPR "represents Guardant Health's attempt to challenge the patentability of the asserted claims at the PTAB," and that the FWD found "in favor of Twinstrand Biosciences." Both statements invert the parties. The PTAB records (POA, mandatory notices, certificates of service) show TwinStrand Biosciences is the Petitioner and Guardant Health is the Patent Owner; because the claims survived, the FWD outcome was favorable to Guardant, not Twinstrand. (The "Key legal developments" section correctly identifies TwinStrand as Petitioner, so the two sections are internally inconsistent.)
2. The overview describes the IPR as if Guardant's defense counsel would be the same as in the district court. In fact the forums were staffed by different firms — DLA Piper in D. Del., Wilson Sonsini before the PTAB and Federal Circuit — which matters if you are profiling "the" defense team.