In a significant legal blow to one of the leaders in the liquid biopsy market, a U.S. federal court has issued a final judgment confirming that Guardant Health willfully infringed upon two foundational patents related to high-accuracy DNA sequencing. The ruling, which follows a multi-year legal battle involving TwinStrand Biosciences and the University of Washington, imposes a substantial financial burden on Guardant Health, totaling hundreds of millions of dollars in damages, royalties, and interest. This decision underscores the critical importance of intellectual property in the rapidly evolving field of precision oncology and genomic diagnostics.
The final judgment, handed down in the U.S. District Court for the District of Delaware, upholds a November 2023 jury verdict that found Guardant’s sequencing methods utilized proprietary technology developed at the University of Washington and exclusively licensed to TwinStrand Biosciences. The court’s decision validates the claims that Guardant Health knowingly incorporated these patented methods into its commercial products without obtaining the necessary licenses, leading to the designation of "willful" infringement.
The Financial Scope of the Judgment
The financial implications of the court’s ruling are extensive. While the initial jury award in late 2023 set a baseline for damages, the final judgment includes several layers of financial restitution intended to compensate the plaintiffs for past and ongoing use of the technology. According to the court documents and statements from TwinStrand, the total financial package includes:
- Accrued Royalties: $119.4 million representing the calculated value of Guardant’s use of the technology over the period of infringement.
- Supplemental Damages: $19.5 million added to the initial findings.
- Interest: $22.9 million in accrued interest on the unpaid damages and royalties.
- Quarterly Accounting: A mandate for Guardant Health to provide TwinStrand and the University of Washington with a detailed quarterly accounting of all relevant U.S. sales, ensuring that ongoing royalties are accurately tracked and paid.
The judgment covers several of Guardant’s most prominent products, including the Guardant360 tests, which are widely used by oncologists to guide treatment decisions for patients with advanced cancer. It also encompasses older versions of the Guardant Reveal and Guardant Shield tests. Guardant Shield recently gained significant attention following its FDA approval as a blood-based screening tool for colorectal cancer, making the legal stakes surrounding its underlying technology particularly high.
The Innovation at Stake: Duplex Sequencing
At the heart of the dispute is a technology known as Duplex Sequencing. Developed at the University of Washington by Jesse Salk—then a medical student and now a prominent figure in the genomics community—along with his academic colleagues, Duplex Sequencing was designed to overcome a fundamental limitation in conventional next-generation sequencing (NGS).
Standard NGS methods, while revolutionary, often struggle with a "noise" problem. When sequencing DNA, chemical errors or mechanical artifacts can be introduced, leading to false positives where the system identifies a genetic mutation that does not actually exist in the patient’s biological sample. For liquid biopsies, which seek to detect tiny fragments of tumor DNA (ctDNA) circulating in a patient’s blood, this lack of precision can be a major hurdle.
TwinStrand’s Duplex Sequencing technology achieves a higher order of accuracy by independently tagging and sequencing both strands of a single DNA duplex molecule. By comparing the results from the two complementary strands, the system can distinguish between true biological mutations (which appear on both strands) and technical errors (which typically appear on only one). This method provides a level of sensitivity and specificity that allows clinicians to detect variants at a frequency of less than one in a million, a capability essential for early cancer detection and monitoring minimal residual disease (MRD).
"Duplex Sequencing solved an accuracy problem the sequencing field had worked on for years," stated Chad Waite, Chair of TwinStrand Biosciences. He noted that the court’s judgment affirms that Guardant Health built its commercial success on this foundational invention without proper authorization.
Chronology of the Legal Conflict
The path to this final judgment has been marked by years of research, commercial expansion, and eventually, intense litigation.
2010–2013: Jesse Salk and his team at the University of Washington conduct the primary research that leads to the invention of Duplex Sequencing. The university files for patent protection on these methods.
2015: TwinStrand Biosciences is founded to commercialize the Duplex Sequencing technology, securing an exclusive license from the University of Washington.
2014–2020: Guardant Health emerges as a powerhouse in the liquid biopsy space, launching Guardant360 and expanding its portfolio into cancer screening and monitoring. During this time, the company becomes a dominant player in the market for "comprehensive genomic profiling."
2021: Litigation begins as TwinStrand and the University of Washington allege that Guardant’s core sequencing processes infringe upon the patents derived from Salk’s research.
November 2023: A federal jury in Delaware delivers a verdict in favor of TwinStrand and the University of Washington, finding that Guardant Health infringed on two specific patents and that the infringement was willful. The jury initially awards approximately $83.4 million in damages.
August 2024: The court issues the final judgment, which includes the expanded financial penalties and the requirement for ongoing royalty payments and sales reporting.
Guardant Health’s Defense and Market Response
In response to the judgment, Guardant Health has sought to reassure investors and healthcare providers that its current operations remain stable. The company has maintained that its latest versions of the Shield and Reveal products are not subject to the court order, as they have been updated to utilize different methodologies.
"Current Guardant Reveal and Shield products are excluded from the court order," Guardant said in an official statement. Furthermore, the company noted that it has already validated "design improvements" for the Guardant360 platform and related services. These modifications are intended to circumvent the patented methods in question, thereby excluding those products from future royalty impacts.
However, the legal battle is not entirely over. Guardant has historically signaled its intent to challenge such rulings through the appeals process. Additionally, patent-related proceedings continue before the U.S. Patent and Trademark Office (USPTO) and the Patent Trial and Appeal Board (PTAB), where the validity of the patents themselves may still be contested.
Broader Implications for the Liquid Biopsy Industry
The ruling against Guardant Health sends a clear signal to the biotechnology and diagnostics industry regarding the enforceability of foundational genomic patents. The liquid biopsy market is currently one of the most competitive sectors in healthcare, with companies like Natera, Grail (recently spun off from Illumina), and Exact Sciences vying for dominance in a market projected to be worth tens of billions of dollars over the next decade.
The case highlights several key trends and implications for the sector:
1. Intellectual Property as a Competitive Moat
In the rush to bring liquid biopsy tests to market, companies must navigate a complex web of IP. This judgment demonstrates that even established market leaders are vulnerable to litigation if their core technology is found to be built upon unlicensed academic research. For startups like TwinStrand, this victory validates their business model of licensing and protecting high-value innovation.
2. The High Cost of Willful Infringement
The court’s finding of "willful" infringement is particularly damaging. In patent law, a finding of willfulness suggests that the infringer knew of the patent and disregarded it. This often leads to enhanced damages. The significant interest and supplemental damages added to the Guardant judgment serve as a cautionary tale for companies regarding the risks of "building first and asking for licenses later."
3. The Necessity of Technical Redesign
Guardant’s move to validate "design improvements" highlights the technical agility required in the diagnostics space. To avoid crippling royalty payments that could erode profit margins, companies must be prepared to re-engineer their sequencing pipelines—a process that involves significant R&D costs and the need for new clinical validation to ensure the tests remain effective.
4. Impact on Patient Care and Clinical Confidence
While the legal battle focuses on patents and profits, the underlying technology is a matter of patient health. Guardant360 and its competitors are used to match cancer patients with life-saving targeted therapies. The industry must ensure that legal disputes and subsequent technical "design-arounds" do not compromise the accuracy or availability of these tests for the clinicians and patients who rely on them.
Future Outlook
As the dust settles on this specific judgment, the focus shifts to the ongoing proceedings at the PTAB and the potential for a federal appeal. TwinStrand has expressed its commitment to continuing the defense of its intellectual property. "We will continue to defend these patents and the innovation they protect for the researchers and clinicians worldwide who rely on the accuracy our technology makes possible," said Chad Waite.
For Guardant Health, the challenge will be managing the financial outflow of the judgment while maintaining its lead in the colorectal cancer screening market with Shield. The company’s ability to successfully transition to non-infringing methods without losing diagnostic sensitivity will be a key metric for investors to watch in the coming quarters.
The University of Washington’s involvement also highlights the pivotal role of academic institutions in the biotech ecosystem. The revenue generated from this judgment and future royalties will likely flow back into the university’s research programs, potentially fueling the next generation of genomic breakthroughs.
In the broader context, this case serves as a landmark in the "sequencing wars," illustrating that in the world of high-stakes diagnostics, the code of the law is as complex and consequential as the code of the human genome.
