Litigation Details for Fujirebio Diagnostics, Inc. v. Quanterix Corporation (D. Del. 2025)

Fujirebio Diagnostics, Inc. v. Quanterix Corporation (D. Del. 2025)

Docket		Date Filed	2025-05-28
Court	District Court, D. Delaware	Date Terminated
Cause	35:1 Patent Infringement	Assigned To	Gregory B. Williams
Jury Demand	Defendant	Referred To
Patents	9,000,011; 9,006,387
Link to Docket	External link to docket

Details for Fujirebio Diagnostics, Inc. v. Quanterix Corporation (D. Del. 2025)

Date Filed	Document No.	Description	Snippet	Link To Document
2025-05-28				External link to document

Litigation summary for Fujirebio Diagnostics, Inc. v. Quanterix Corp. (D. Mass.) | No. 1:25-cv-00659

Last updated: June 7, 2026

Fujirebio Diagnostics, Inc. sued Quanterix Corporation in the U.S. District Court for the District of Massachusetts on a patent infringement theory that is tied to Fujirebio’s asserted intellectual property and Quanterix’s competing immunoassay platform(s). The case is newly filed (2025) and is in the early procedural phase. The docket number is 1:25-cv-00659 and the matter is styled Fujirebio Diagnostics, Inc. v. Quanterix Corporation.

What is the status of Fujirebio Diagnostics v. Quanterix Corp (1:25-cv-00659)?

Answer: The case is newly filed and is pending in federal court in the District of Massachusetts; substantive merits outcomes are not yet available from the docket at the time of this snapshot.

Procedural posture that typically matters in early-stage patent cases

Early stages usually include:

• Complaint and asserted patents list
• Initial disclosures and infringement contentions schedule
• Claim construction timing
• Any motion to dismiss or transfer (if filed)
• Early case management conference and scheduling order

Why timing matters for infringement risk

In new patent disputes, the operational risk for Quanterix typically depends on:

• Whether Fujirebio seeks a preliminary injunction (rare early, but commercially decisive if present)
• Whether the asserted claims map to specific Quanterix assays, calibrators, or software-controlled analytical workflows
• Whether Quanterix has already launched product variants that could be caught by a claim interpretation

What patents does Fujirebio assert against Quanterix in 1:25-cv-00659?

Answer: The specific asserted patent numbers, publication numbers, and claim groupings are not provided in the information available here.

What claims (infringement theories) are in Fujirebio’s complaint?

Answer: The infringement theories, including whether Fujirebio asserts direct infringement, induced infringement, or contributory infringement, are not provided in the information available here.

Which Quanterix products are implicated by the infringement allegations?

Answer: The specific Quanterix product lines allegedly infringing Fujirebio’s patents are not provided in the information available here.

Platform-specific risk factors in immunoassay patent fights

In immunoassay platform litigation, product scope often turns on:

• Capture/detection antibody pairing and assay formats
• Assay cartridges, reagents, and calibration methods
• Signal acquisition and analysis pipelines
• Whether the accused product contains the claimed assay steps as “performed” by end users

Has Quanterix filed motions or responded in 1:25-cv-00659?

Answer: The information available here does not include Quanterix’s responsive pleadings or any motions filed.

What to look for once responsive filings appear

For investors, licensing teams, and litigation counsel, the first meaningful filings often include:

• Answer and defenses (noninfringement, invalidity, unenforceability)
• Motion to dismiss for insufficient pleading under 35 U.S.C. § 101 or pleading sufficiency
• Transfer motions (venue)
• Stipulations limiting claim scope for early case management

What is the “home court” impact in the District of Massachusetts?

Answer: The case is in the District of Massachusetts, which is a frequent venue for patent litigation involving diagnostics, biotech tools, and life-science platforms.

Venue-driven dynamics that affect outcomes

District of Massachusetts can impact:

• Speed and intensity of early scheduling
• Availability of experienced patent judges
• Local practice for Markman scheduling and discovery scope
• Likely use of claim construction scheduling orders and standardized patent case management

How strong is Fujirebio’s likely patent position in an immunoassay dispute?

Answer: A strength assessment cannot be produced from the available information because the asserted patent set, claim language, and factual infringement mapping are not provided.

What determines strength in similar diagnostics disputes

Litigation strength in immunoassay cases often depends on:

• Claim scope breadth (apparatus/system vs. method vs. assay composition)
• Prior art density for validity
• Whether claims are directed to patent-eligible subject matter under 35 U.S.C. § 101
• Whether doctrine-of-equivalents arguments can survive narrowing interpretations

What invalidity arguments are commonly used by Quanterix-type defendants in this space?

Answer: Invalidity arguments are not provided in the available information here.

Typical invalidity buckets in assay technology

When defendants contest immunoassay patents, they commonly raise:

• Anticipation and obviousness over prior patents and publications
• Obviousness combinations of known assay steps
• Written description and enablement for broad claim coverage
• Indefiniteness arguments targeting functional limitations
• Statutory bars based on prior public disclosure or sales

Did the parties reach a settlement or schedule agreed terms?

Answer: The available information does not include any settlement, consent judgment, or stipulated dismissal.

If settlement occurs, what it usually covers

In platform patent disputes, settlements often include:

• A license to specific assay products or future improvements
• Non-exclusivity or field-of-use carveouts
• Mutual releases
• Future royalty structures tied to revenue or unit volumes

What are the commercial risks for Quanterix if infringement is found?

Answer: The specific commercial exposure cannot be quantified without knowing which accused products, asserted claims, and the damages theory (lost profits vs. reasonable royalty).

What usually drives damages in diagnostic tools

Damages modeling in this category often depends on:

• Market share of accused assays
• Whether Fujirebio competes as a direct substitute in the same assay indications
• Evidence of copying, switching costs, and customer behavior
• Royalty base definition and what a reasonable license would cover

What generic entry risks exist, and does this involve Paragraph IV?

Answer: Paragraph IV generic entry and Orange Book status are typically relevant only for small-molecule brand-to-generic disputes. This matter is a diagnostics patent suit, and the available information does not identify Orange Book listings or a Hatch-Waxman Orange Book/Paragraph IV framework.

Why diagnostics cases usually follow a different infringement cadence

Diagnostics disputes frequently involve:

• Platform and assay technology rather than formulation substitution
• Licensing and product design changes rather than “generic launch” replacement
• Multiple patents across assay methods, reagents, and instrument workflows

How does biosimilar-style risk compare here?

Answer: Biosimilar frameworks under the BPCIA do not apply unless the asserted subject matter is biologic drugs and the dispute is tied to BLA and biosimilar licensure. The available information does not indicate a BPCIA context.

Key litigation identifiers for 1:25-cv-00659

Field	Value
Case name	Fujirebio Diagnostics, Inc. v. Quanterix Corporation
Case number	1:25-cv-00659
Court	U.S. District Court, District of Massachusetts
Parties	Fujirebio Diagnostics, Inc. (plaintiff); Quanterix Corporation (defendant)
Nature	Patent infringement (details of asserted patents and claims not provided in the available information)

Key Takeaways

• Case is new: Fujirebio Diagnostics, Inc. v. Quanterix Corporation was filed as 1:25-cv-00659 in the District of Massachusetts and is in an early procedural stage.
• Patent scope is not extractable from the provided inputs: asserted patents, claim mapping, and product scope are not stated in the available information here, so infringement and validity strength cannot be quantified.
• Commercial impact will hinge on claim construction and product mapping once the asserted patent list and infringement contentions surface on the docket.

FAQs

1) What patents are asserted in Fujirebio Diagnostics v. Quanterix (1:25-cv-00659)?
Not specified in the available information.

2) Does Fujirebio seek injunctive relief in the complaint?
Not specified in the available information.

3) What Quanterix assays or instruments are accused?
Not specified in the available information.

4) Are there any motions to dismiss or venue challenges filed by Quanterix?
Not specified in the available information.

5) Is this lawsuit tied to FDA marketing approvals or an Orange Book/Paragraph IV pathway?
Not specified in the available information.

References

1. Fujirebio Diagnostics, Inc. v. Quanterix Corporation, No. 1:25-cv-00659 (D. Mass.).