TwinStrand Biosciences Secures More Than $245 Million Judgment in Patent Infringement Case Against Guardant Health
TwinStrand Biosciences, Inc., the developer of Duplex Sequencing® technology, announced that the U.S. District Court for the District of Delaware entered a final judgment on August 21, 2026, in favor of TwinStrand and the University of Washington (UW) in their patent infringement litigation against Guardant Health, Inc. (Nasdaq: GH).
The judgment preserves a November 2023 jury verdict that found Guardant Health willfully infringed two patents covering key aspects of TwinStrand’s Duplex Sequencing technology. The patents were found to have been infringed across 11 Guardant Health products and services that generate royalty obligations. Under the final judgment, TwinStrand and the University of Washington will receive more than $245.2 million in damages, accrued royalties and interest for infringement occurring through May 31, 2026.
The decision represents a major development in a long-running intellectual property dispute involving technology designed to improve the accuracy of DNA sequencing. It also establishes ongoing royalty obligations for certain Guardant Health products and services through the expiration of the patents in March 2033.
Court Upholds Earlier Jury Verdict
The latest judgment follows several stages of litigation and post-trial proceedings. In November 2023, a federal jury determined that Guardant Health had willfully infringed two patents associated with TwinStrand’s Duplex Sequencing technology.
The jury awarded $83.4 million in damages for infringement occurring through June 30, 2023. Following the jury’s decision, additional proceedings were conducted to determine supplemental damages, royalties and interest associated with continued sales of the products covered by the verdict.
The court issued a ruling on June 16, 2026, resolving the parties’ post-trial motions. Guardant Health’s efforts to overturn the jury verdict or obtain a new trial were unsuccessful. The final judgment entered on August 21 formally incorporates the applicable damages and royalty calculations.
In addition to the original $83.4 million award, the court awarded TwinStrand and UW an additional $19.5 million in supplemental damages associated with sales from July 1, 2023, through February 5, 2024.
The court also awarded $119.4 million in accrued royalties for sales occurring between February 5, 2024, and May 31, 2026. These royalties were calculated using a 6% royalty rate.
The judgment further includes $22.9 million in pre-judgment and post-judgment interest. Collectively, these components bring the total amount awarded to more than $245.2 million through May 31, 2026.
6% Royalty Rate Applies to Covered Products
An important element of the judgment is the royalty rate applied to Guardant Health’s covered products and services.
In determining past damages, the jury applied a 6% royalty to revenue attributed to the products and services found to infringe the TwinStrand patents. According to TwinStrand, the revenue associated with these covered products and services represented approximately 90% of Guardant Health’s total revenue during the relevant infringement period.
The court’s judgment also establishes an ongoing royalty obligation. Guardant Health is required to pay TwinStrand and UW a 6% royalty on U.S. sales of the covered products and services beginning June 1, 2026.
That royalty obligation will continue through March 15, 2033, when the patents are scheduled to expire. Payments are required to be made quarterly under the terms of the judgment.
Interest will also continue to accrue on any unpaid portion of the judgment, adding another financial consequence for amounts that remain outstanding.
Patents at the Center of the Dispute
The litigation involved two U.S. patents: U.S. Patent No. 10,287,631 and U.S. Patent No. 10,760,127.
Both patents relate to technology underlying TwinStrand’s Duplex Sequencing platform. TwinStrand describes Duplex Sequencing as a technology developed to address the challenge of accurately identifying rare mutations and other low-frequency genetic changes in DNA.
Traditional sequencing approaches can be affected by errors introduced during sample preparation, amplification or the sequencing process itself. These errors can make it difficult to distinguish a genuine low-frequency mutation from an artifact generated during analysis.
Duplex Sequencing uses information from both complementary strands of DNA to improve confidence in sequence calls. By requiring evidence from both strands, the technology is designed to reduce the likelihood that technical errors will be interpreted as true biological mutations.
The technology has applications in areas where high analytical accuracy is particularly important, including cancer research, liquid biopsy development, molecular diagnostics, drug development and other genomic applications.
TwinStrand maintains that its patented innovations represent important advances in sequencing accuracy and that the intellectual property is central to the company’s technology platform.
Court Upholds Patent Validity
The final judgment addresses not only infringement and damages but also the validity of the patents asserted in the litigation.
The court upheld the validity of the asserted claims of both TwinStrand patents. In entering judgment, the court adopted language proposed by TwinStrand concerning patent validity rather than accepting Guardant Health’s position that no judgment regarding validity should be entered.
TwinStrand said the validity determination is particularly significant because it reinforces the strength of the patents supporting its Duplex Sequencing technology.
However, patent-related proceedings involving the patents remain ongoing before the U.S. Patent and Trademark Office and the Patent Trial and Appeal Board. TwinStrand noted that neither of the two patents has been invalidated.
The continued proceedings mean that the broader intellectual property landscape surrounding the patents remains active. Nevertheless, the Delaware District Court’s final judgment represents a significant favorable outcome for TwinStrand and UW in the infringement litigation.
TwinStrand Defends Its Intellectual Property
Chad Waite, chair of the TwinStrand board of directors, said the company remained confident throughout the litigation that the evidence would support its position.
Waite emphasized the importance of Duplex Sequencing in addressing longstanding accuracy challenges within the sequencing field. He characterized the court’s judgment as confirmation of the jury’s finding that Guardant Health had used products based on the patented invention without obtaining a license.
According to TwinStrand, the company intends to continue defending its intellectual property and protecting the technology underlying its sequencing platform.
Waite also highlighted the court’s decision regarding patent validity, describing it as especially meaningful to the company. TwinStrand views the patents as an important foundation for the technology used by researchers and clinicians seeking highly accurate genomic information.
The company said it remains committed to protecting the intellectual property that supports Duplex Sequencing and the applications built around the technology.
Guardant Health Counterclaims Resolved
The litigation also involved counterclaims brought by Guardant Health against TwinStrand. According to TwinStrand, all of Guardant Health’s counterclaims were either dismissed by the court or withdrawn before trial.
The resolution of those counterclaims further narrowed the issues remaining in the dispute and allowed the court to proceed with the final judgment concerning infringement, damages, royalties and patent validity.
The final decision therefore provides TwinStrand and UW with a comprehensive judgment covering both the financial consequences of past infringement and the continuing royalty obligations associated with the covered products.
11 Guardant Health Products and Services Covered
The final judgment applies to 11 Guardant Health products and services identified as royalty-bearing products and services in the litigation.
These include:
- Guardant360 Lab Developed Test
- Guardant360 CDx
- GuardantOMNI
- Guardant Reveal / LUNAR-1
- Guardant360 Response
- Guardant360 TissueNext
- Guardant HEME
- GuardantINFINITY / Sirius
- Guardant LUNAR-2 / Shield
- Guardant COMPANION
- Guardant EXPLORE
These products represent a broad portion of Guardant Health’s portfolio of genomic testing and precision oncology services.
The judgment also requires Guardant Health to provide TwinStrand and the University of Washington with quarterly accounting reports detailing U.S. sales of the covered products and services.
The reporting requirement is intended to provide the information necessary to calculate the royalties owed under the judgment and to monitor compliance with the ongoing royalty obligation.
Implications for Genomic Testing and Precision Medicine
The case highlights the growing importance of intellectual property surrounding genomic technologies. As sequencing becomes increasingly integrated into oncology, drug development and precision medicine, the accuracy and reliability of genomic data have become critical factors in clinical and research applications.
Technologies capable of detecting rare genetic variants can be particularly valuable in cancer research and liquid biopsy testing, where clinically meaningful mutations may occur at very low frequencies within a large background of normal DNA.
Higher sequencing accuracy can help researchers and diagnostic developers distinguish true biological signals from technical artifacts. This distinction can influence research conclusions, biomarker development and the interpretation of molecular testing results.
The litigation between TwinStrand and Guardant Health therefore extends beyond a conventional commercial dispute. It also reflects the competitive importance of technologies designed to improve the accuracy of genomic analysis.
For TwinStrand, the judgment provides both financial compensation and recognition of the importance of its patented technology. The ongoing royalty requirement also creates a mechanism through which the company can continue receiving compensation for covered uses during the remaining life of the patents.
Financial and Strategic Significance
The more than $245.2 million judgment represents a substantial financial outcome for TwinStrand and UW. The award includes compensation for historical infringement as well as accrued royalties and interest.
The future 6% royalty on covered U.S. sales through March 15, 2033 could represent an additional source of revenue depending on the level of sales generated by the products covered by the judgment.
For Guardant Health, the ruling creates an ongoing financial obligation associated with specific products and services. The requirement to provide quarterly sales accounting also introduces a continuing reporting responsibility for the company.
The final judgment therefore has both immediate and long-term implications for the parties.
TwinStrand’s victory in the Delaware patent case marks an important milestone in its effort to protect Duplex Sequencing and the intellectual property supporting the technology. The court’s final judgment confirms the earlier jury finding of willful infringement, preserves the $83.4 million original damages award and adds substantial supplemental damages, accrued royalties and interest.
The total financial award through May 31, 2026 exceeds $245.2 million. In addition, the court has ordered a 6% royalty on qualifying U.S. sales of the covered products and services beginning June 1, 2026, continuing through the patents’ expiration in March 2033.
The judgment also upholds the validity of the asserted claims of U.S. Patent Nos. 10,287,631 and 10,760,127, although related proceedings before the U.S. Patent and Trademark Office and Patent Trial and Appeal Board remain ongoing.
For TwinStrand, the outcome reinforces its position that Duplex Sequencing represents an important technological advancement in the pursuit of greater sequencing accuracy. The company intends to continue defending its intellectual property as researchers, clinicians and diagnostic developers increasingly depend on advanced genomic technologies.
The case also illustrates the growing commercial and strategic importance of patents in precision medicine. As genomic sequencing continues to play a larger role in cancer detection, treatment selection, biomarker research and pharmaceutical development, ownership of foundational sequencing technologies can have significant implications across the biotechnology and healthcare industries.
With the final judgment now entered, TwinStrand and UW have secured a substantial financial award and ongoing royalty protections related to the two patents. At the same time, the continued patent proceedings mean that the broader intellectual property dispute is not necessarily finished. TwinStrand has made clear that it intends to continue defending the patents and the innovations they represent.
The August 21, 2026 judgment consequently stands as a major development for TwinStrand Biosciences, strengthening the company’s intellectual property position while potentially creating a long-term financial framework around the use of its patented Duplex Sequencing technology.
About TwinStrand Biosciences
TwinStrand Biosciences is a precision genomics company advancing highly accurate DNA sequencing through its patented TwinStrand Duplex Sequencing® technology, originally developed at the University of Washington. Duplex Sequencing achieves more than 10,000-fold greater accuracy than conventional next-generation sequencing by independently sequencing and comparing both complementary strands of each DNA molecule.
This enables reliable detection of ultra-low-frequency genetic variants that conventional methods often cannot distinguish from background sequencing errors. The technology supports applications across oncology, molecular diagnostics, genetic toxicology and drug development. TwinStrand collaborates with leading pharmaceutical companies, molecular diagnostics developers, academic institutions and research organizations, and its intellectual property portfolio includes more than 150 issued patents and patent applications worldwide. For more information, visit www.twinstrandbio.com.