Japan IP High Court Revives Broad Institute’s CRISPR Patent, Overturning JPO Priority Rights Ruling

Japan’s Intellectual Property High Court (IP High Court) has overturned a Japan Patent Office (JPO) decision invalidating a CRISPR-Cas9 patent held by the Broad Institute, the Massachusetts Institute of Technology (MIT), and Harvard University. The court found that the institutions could validly rely on earlier U.S. filings as priority documents despite a dispute over ownership of those rights. The ruling, issued in April 2026, marks a significant reversal in the global battle over CRISPR gene-editing patents and extends Broad Institute’s legal record to the Japanese market.

Background: The JPO Invalidation

The case was triggered by a patent invalidation action filed by South Korean biotech company ToolGen against a Broad Institute CRISPR patent in Japan. ToolGen argued that the chain of title in the U.S. provisional application—which formed the basis of Broad’s priority claim—was defective: the rights were distributed across multiple institutions (MIT, Harvard, the Whitehead Institute) without proper formal consolidation at the time of filing. The JPO agreed in April 2025, invalidating the patent on that ground.

Broad Institute challenged the JPO’s ruling before the IP High Court under Japan’s patent invalidation trial appeal process. In April 2026, the court sided with Broad, holding that the institutions could legitimately assert priority based on their earlier U.S. filings. The full text of the judgment has not been released as of this writing.

The Global CRISPR Patent Landscape

CRISPR-Cas9 gene editing is one of the most contested technologies in patent law history. The core dispute centers on which institution first demonstrated CRISPR’s functionality in eukaryotic (mammalian) cells—a distinction that determines patent priority in most jurisdictions.

Jennifer Doudna of UC Berkeley and Emmanuelle Charpentier published the foundational CRISPR mechanism in prokaryotic systems in 2012, earning them the Nobel Prize in Chemistry in 2020. Broad Institute’s Feng Zhang claimed to have been the first to apply CRISPR to eukaryotic cells in 2013 and secured U.S. patents covering that application.

In the United States, the Patent Trial and Appeal Board (PTAB) ruled in Broad’s favor in a 2022 interference proceeding—a decision affirmed by the Federal Circuit in 2024. In March 2026, PTAB reaffirmed Broad’s priority following a supplemental priority statement round. In Europe, the outcome has been more mixed, with the European Patent Office and national courts issuing varying decisions across jurisdictions.

Priority Rights and Chain of Title

The legal question at the heart of this case—whether the chain of title in U.S. provisional applications was valid for the purpose of claiming priority in Japan—has broader implications for international patent practice. Under the Paris Convention, a patent applicant claiming priority from an earlier foreign filing must demonstrate that the priority application’s ownership was properly vested in the same legal entity or its predecessor in interest.

ToolGen argued that at the time Broad filed its provisional application, rights were distributed across multiple institutions without proper formal consolidation. The IP High Court’s rejection of this argument—while the full rationale awaits publication—likely reflects a finding that employment agreements and institutional assignment arrangements sufficiently established a unified ownership interest for priority purposes, even absent explicit written assignment documents.

Industry Implications

CRISPR technology has moved well beyond the laboratory. Casgevy, the first approved CRISPR-based therapeutic, received regulatory clearance in the United States, the United Kingdom, and Japan in 2023–2024 for sickle cell disease and beta-thalassemia. Multiple other CRISPR therapies are in late-stage clinical trials across oncology, rare disease, and infectious disease indications. Commercial licensing potential runs into the tens of billions of dollars, and patent ownership in each jurisdiction directly determines licensing terms and market access conditions.

The IP High Court ruling means that in Japan, Broad Institute’s CRISPR patents remain valid and enforceable. Japanese pharmaceutical companies, agricultural biotech firms, and research institutions using CRISPR technology—or planning to—may need to revisit their licensing strategies, particularly regarding which entity controls the relevant patents in the Japanese market.

Whether ToolGen will escalate to Japan’s Supreme Court remains to be seen. The broader question of fragmented CRISPR patent rights across jurisdictions continues to fuel calls for a unified licensing pool—a model that could streamline access for downstream innovators while ensuring fair returns to the foundational patent holders.