---
schema_version: "secwatch.filing_event.v1"
accession: "0001559053-22-000040"
form_type: "8-K"
ticker: "PRTA"
cik: "0001559053"
company_name: "PROTHENA CORP PUBLIC LTD CO"
filed_at: "2022-10-31T23:59:59+00:00"
generated_at: "2026-06-22T21:39:36.151907+00:00"
event_type: "other_material"
sentiment: "neutral"
materiality_score: 0.4
calibrated_materiality_score: 0.4
confidence: "high"
source: SEC EDGAR
---

# Prothena enters sublease for 31,157 sq ft in Brisbane, CA; rent starts July 2023

## Summary
- PBI subleases ~31,157 sq ft from Arcus Biosciences at 1800 Sierra Point Parkway, Brisbane, CA.
- Term ends Sep 30, 2028; rent begins Jul 1, 2023 with monthly base rent ~$241,467 in year 1.
- Rent increases ~3.5% annually; first six months rent abated.
- Improvement allowance of ~$9.35M from sublandlord for construction and prep.
- Standby letter of credit ~$860,360 posted to secure obligations.

## SEC filing metadata
- accession: 0001559053-22-000040
- form_type: 8-K
- ticker: PRTA
- cik: 0001559053
- company_name: PROTHENA CORP PUBLIC LTD CO
- filed_at: 2022-10-31T23:59:59+00:00
- event_type: other_material
- sentiment: neutral
- materiality_score: 0.4
- calibrated_materiality_score: 0.4
- confidence: high
- sec_items: 1.01, 9.01
- EDGAR index: https://www.sec.gov/Archives/edgar/data/1559053/000155905322000040/0001559053-22-000040-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/1559053/000155905322000040/prta-20221028.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0001559053-22-000040
- JSON: https://secwatch.observer/filing/0001559053-22-000040.json
- Plain text: https://secwatch.observer/filing/0001559053-22-000040.txt

## Key facts
- Material Agreements
  PROTHENA CORP PUBLIC LTD CO entered into Sublease with Arcus Biosciences, Inc. valued at approximately $9,347,100.00 (effective 2022-10-28).
  - Action: entry
  - Agreement: lease
  - Counterparty: Arcus Biosciences, Inc.
  - Value: approximately $9,347,100.00
  - Effective: 2022-10-28
  source text: On October 28, 2022, Prothena Biosciences Inc (“PBI”), a wholly owned subsidiary of Prothena Corporation plc (the “Company”), entered into a Sublease (the “Sublease”) with Arcus Biosciences, Inc., a Delaware corporation (“Sublandlord”), to sublease approximately 31,157 square feet of office and laboratory space located at 1800 Sierra Point Parkway, Brisbane, California (the “New Facility”).
  evidence_url: https://www.sec.gov/Archives/edgar/data/1559053/000155905322000040/0001559053-22-000040-index.htm

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