---
schema_version: "secwatch.filing_event.v1"
accession: "0001171843-26-000676"
form_type: "8-K"
ticker: "ABUS"
cik: "0001447028"
company_name: "Arbutus Biopharma Corp"
filed_at: "2026-02-06T23:59:59+00:00"
generated_at: "2026-05-16T04:04:19.171467+00:00"
event_type: "litigation"
sentiment: "neutral"
materiality_score: 0.85
calibrated_materiality_score: 0.85
confidence: "high"
source: SEC EDGAR
---

# Arbutus patent case vs Moderna to proceed in Delaware; Section 1498 defense limited

## Summary
- Court denies Moderna's summary judgment on Section 1498 for most vaccine doses; only government employee doses go to Court of Federal Claims.
- Prosecution history estoppel bars Arbutus from asserting doctrine of equivalents on molar ratio claims; literal infringement required.
- Indefiniteness challenges dismissed; factual disputes on patent validity reserved for jury.
- Case covers 500M+ doses of Moderna's COVID-19 vaccine; $8.2B in government spending referenced.

## SEC filing metadata
- accession: 0001171843-26-000676
- form_type: 8-K
- ticker: ABUS
- cik: 0001447028
- company_name: Arbutus Biopharma Corp
- filed_at: 2026-02-06T23:59:59+00:00
- event_type: litigation
- sentiment: neutral
- materiality_score: 0.85
- calibrated_materiality_score: 0.85
- confidence: high
- sec_items: 8.01, 9.01
- EDGAR index: https://www.sec.gov/Archives/edgar/data/1447028/000117184326000676/0001171843-26-000676-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/1447028/000117184326000676/f8k_020626.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0001171843-26-000676
- JSON: https://secwatch.observer/filing/0001171843-26-000676.json
- Plain text: https://secwatch.observer/filing/0001171843-26-000676.txt

This AI-assisted summary is a reading aid. Review the linked SEC EDGAR filing before relying on any specific claim.