---
schema_version: "secwatch.filing_event.v1"
accession: "0001559053-23-000021"
form_type: "8-K"
ticker: "PRTA"
cik: "0001559053"
company_name: "PROTHENA CORP PUBLIC LTD CO"
filed_at: "2023-07-10T23:59:59+00:00"
generated_at: "2026-06-13T10:34:18.108952+00:00"
event_type: "m_and_a"
sentiment: "positive"
materiality_score: 0.75
calibrated_materiality_score: 0.75
confidence: "high"
source: SEC EDGAR
---

# Prothena expands BMS tau collaboration to global license; $55M fee, milestones up to $562.5M

## Summary
- BMS exercises option to convert US-only tau license to global; Prothena receives $55M exercise fee.
- Milestone payments increased from up to $465M to up to $562.5M under global agreement.
- Prothena eligible for up to $15M in CMC expense reimbursement.
- Tiered royalties on net sales unchanged; term runs product-by-product until end of royalty term.
- Global license supersedes prior US-only tau license dated July 30, 2021.

## SEC filing metadata
- accession: 0001559053-23-000021
- form_type: 8-K
- ticker: PRTA
- cik: 0001559053
- company_name: PROTHENA CORP PUBLIC LTD CO
- filed_at: 2023-07-10T23:59:59+00:00
- event_type: m_and_a
- sentiment: positive
- materiality_score: 0.75
- calibrated_materiality_score: 0.75
- confidence: high
- sec_items: 1.01, 9.01
- EDGAR index: https://www.sec.gov/Archives/edgar/data/1559053/000155905323000021/0001559053-23-000021-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/1559053/000155905323000021/prta-20230705.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0001559053-23-000021
- JSON: https://secwatch.observer/filing/0001559053-23-000021.json
- Plain text: https://secwatch.observer/filing/0001559053-23-000021.txt

## Key facts
- Material Agreements
  PROTHENA CORP PUBLIC LTD CO entered into Tau Global License Agreement with Bristol Myers Squibb valued at $55 million (effective 2023-07-05).
  - Action: entry
  - Agreement: license
  - Counterparty: Bristol Myers Squibb
  - Value: $55 million
  - Effective: 2023-07-05
  source text: On July 5, 2023 and pursuant to the option exercised by BMS under the Master Collaboration Agreement, Prothena and BMS entered into a Global License Agreement (the “Tau Global License Agreement”) granting BMS the exclusive license to develop, manufacture and commercialize Tau Collaboration Products globally for any and all uses or purposes with respect to any human or animal disease, disorder or condition.
  evidence_url: https://www.sec.gov/Archives/edgar/data/1559053/000155905323000021/0001559053-23-000021-index.htm

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