CRISPR Patent War: PTAB Reaffirms Broad Institute’s Priority Rights in Landmark Ruling

On March 27, 2026, the Patent Trial and Appeal Board (PTAB) reaffirmed that the Broad Institute of MIT and Harvard holds the priority rights for the invention of applying CRISPR-Cas9 technology to eukaryotic cells. What began in 2012 as a dispute in the most consequential patent battle in biotechnology history has now reached what IP professionals and biotech researchers worldwide are calling a “textbook resolution.” This article examines the significance of this historic decision, what “patent priority” actually means, and the concrete implications for Japan’s pharmaceutical and biotech industries.

1. The Origins of the CRISPR Patent Battle — The Race of 2012

CRISPR-Cas9 is a revolutionary genome editing tool. Its ability to precisely cut and edit specific DNA sequences has transformed science, medicine, and industry — from treating genetic diseases to agricultural applications to accelerating fundamental research. Its scientific value was officially recognized with the 2020 Nobel Prize in Chemistry, awarded to Jennifer Doudna and Emmanuelle Charpentier.

However, the patent rights to this revolutionary technology became the subject of a world-dividing legal battle. On one side: the group of Dr. Jennifer Doudna at UC Berkeley. On the other: the group of Dr. Feng Zhang at the Broad Institute.

The Doudna group submitted a paper to Science on May 25, 2012 (published August 17, 2012), demonstrating that CRISPR-Cas9 could edit any DNA sequence in vitro, and filed a provisional patent application in May 2012. Meanwhile, the Broad/Zhang group filed a patent application on December 12, 2012, and used the accelerated examination system to obtain a patent on April 15, 2013 — with its primary claims directed to applying CRISPR-Cas9 to eukaryotic cells (including animal and plant cells).

2. The Interference Proceeding and the Concept of Independent Invention

PTAB initiated Interference proceedings in 2016 to determine which group had first invented the application of CRISPR-Cas9 to eukaryotic cells. In its landmark 2017 ruling, PTAB held that the Doudna group’s in vitro results did not make the application to eukaryotic cells obvious, and that the Zhang group had independently achieved success in eukaryotic cells. This was scientifically nuanced: even knowing that CRISPR-Cas9 worked in prokaryotes or in test tubes, making it function inside the complex nuclear environment of eukaryotic cells was not considered a trivial step.

The Doudna group appealed to the Federal Circuit, and PTAB conducted a further review in 2022, reaching the same conclusion. The March 27, 2026 decision now stands as the final chapter. The heart of the ruling was that new evidence submitted by the Doudna group — 2012 laboratory notebooks, internal emails, and experimental data — was still insufficient to overturn the finding of independent invention by the Broad group regarding eukaryotic cell applications. This decision powerfully illustrates how the quality of scientific record-keeping can determine the outcome of patent disputes.

3. What Is Patent Priority? — A Plain-Language Explanation

Understanding this dispute requires a clear grasp of “patent priority.” Priority is the right that establishes who was “first” to complete an invention, or who was first to file a patent application. When multiple applicants claim the same or similar invention, only the holder of priority can obtain the patent.

Since March 16, 2013, the United States has operated under a “First Inventor to File” system under the America Invents Act (AIA). But for applications like those in this dispute — filed before AIA’s full implementation — the old “first to invent” rules apply. Under that system, the actual date of invention completion must be established through evidence: laboratory notebooks, paper submission dates, inventor testimony, and internal communications. Most countries, including Japan and European nations, operate under a pure first-to-file system and therefore have no equivalent to the U.S. Interference proceeding. This uniquely American complexity is part of what generated nearly 15 years of litigation.

4. What Broad’s Victory Means — Structural Impact on the Biotech Industry

The fact that the Broad Institute holds the patents on applying CRISPR-Cas9 to eukaryotic cells carries enormous economic and legal weight for the global biotechnology industry.

First, there is the matter of licensing revenues. The Broad Institute has actively licensed CRISPR technology through its spinout Editas Medicine while maintaining a two-tier structure: relatively generous licensing for academic research and appropriate royalties for commercial use. The reaffirmation of priority strengthens this framework considerably. The legal relationships with competing licensors, such as CRISPR Therapeutics (affiliated with the UC Berkeley side), will now be resolved with greater clarity.

Second, there is the impact on biopharmaceutical development. Gene and cell therapies using CRISPR-Cas9 — for sickle cell disease, beta-thalassemia, and certain cancers — have already reached the market with FDA approval. Companies developing these products will operate within the Broad’s licensing framework. New entrants will be unable to avoid licensing negotiations.

5. Implications for Japan’s Pharmaceutical and Biotech Industries

In Japan, CRISPR technology is advancing rapidly across agriculture, medicine, and fundamental research. The Broad’s reaffirmed rights have material implications for Japanese companies.

Major pharmaceutical companies — Takeda, Astellas, Daiichi Sankyo — either have CRISPR-based gene therapy pipelines or are incorporating CRISPR-related technologies through partnerships with overseas firms. With Broad’s rights now confirmed, any plans for U.S. development or commercialization will require licensing negotiations with the Broad. Business plans must be revised to account for the time and cost of such negotiations.

For Japanese biotech startups, the cost implications are more pressing. Ventures targeting U.S. listings or partnerships must clearly disclose CRISPR licensing costs in fundraising rounds from Series B onwards. “CRISPR patent clearance” has become a standard due diligence item for investors.

6. Lessons From the Dispute — The Importance of a “Documentation Culture”

The most enduring lesson from this dispute is that rigorous scientific record-keeping is the front line of intellectual property protection. The finding that the Doudna group’s laboratory notebooks were “insufficient to establish priority” serves as a sobering reminder to the scientific community.

Japanese research institutions and companies should treat the digitization of research notebooks, timestamping, and regular internal witness signatures as infrastructure that IP departments and research teams must build together. As international collaborative research increases, understanding priority rules across jurisdictions and cultivating documentation habits become essential defenses against future patent disputes.

This dispute also illuminated the universal tension between the timing of patent filing and the timing of public research disclosure. Publishing a scientific paper first maximizes academic recognition — perhaps even a Nobel Prize — but failing to file patents promptly risks losing exclusive rights. The conflict between “open science” and intellectual property protection is a fundamental challenge that will continue.

Conclusion

PTAB’s reaffirmation of Broad Institute’s priority rights has put a substantive end to the CRISPR patent war. This decision will endure as a textbook case in the history of biotechnology intellectual property. For Japan’s pharmaceutical and biotech industries, the ruling presents three concrete imperatives: restructuring licensing strategies, strengthening documentation culture, and rigorously conducting international IP due diligence. The scientific potential of CRISPR technology continues to expand. To benefit fully from that potential, building a solid intellectual property foundation is an urgent imperative — starting right now.