---
schema_version: "secwatch.filing_event.v1"
accession: "0001558370-23-011634"
form_type: "8-K"
ticker: "MBIO"
cik: "0001680048"
company_name: "MUSTANG BIO, INC."
filed_at: "2023-06-30T23:59:59+00:00"
generated_at: "2026-06-13T14:05:57.036476+00:00"
event_type: "other_material"
sentiment: "neutral"
materiality_score: 0.4
calibrated_materiality_score: 0.4
confidence: "high"
source: SEC EDGAR
---

# Mustang Bio extends asset sale deadline for Worcester facility to July 31, 2023

## Summary
- Mustang Bio and uBriGene amended Asset Purchase Agreement to extend Outside Date from June 30 to July 31, 2023.
- Extension provides additional time to obtain landlord approval for site lease transition.
- Parties may mutually extend in 30-day increments if only condition is landlord consent.

## SEC filing metadata
- accession: 0001558370-23-011634
- form_type: 8-K
- ticker: MBIO
- cik: 0001680048
- company_name: MUSTANG BIO, INC.
- filed_at: 2023-06-30T23:59:59+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/1680048/000155837023011634/0001558370-23-011634-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/1680048/000155837023011634/tmb-20230629x8k.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0001558370-23-011634
- JSON: https://secwatch.observer/filing/0001558370-23-011634.json
- Plain text: https://secwatch.observer/filing/0001558370-23-011634.txt

## Key facts
- Material Agreements
  MUSTANG BIO, INC. amended Asset Purchase Agreement with uBriGene (Boston) Biosciences, Inc. valued at Extended Outside Date to July 31, 2023 (effective 2023-06-29).
  - Action: amendment
  - Agreement: asset purchase
  - Counterparty: uBriGene (Boston) Biosciences, Inc.
  - Value: Extended Outside Date to July 31, 2023
  - Effective: 2023-06-29
  source text: On June 29, 2023 the Company and uBriGene entered into an amendment to the Asset Purchase Agreement (the “ Amendment ”), to extend the Outside Date to July 31, 2023.
  evidence_url: https://www.sec.gov/Archives/edgar/data/1680048/000155837023011634/0001558370-23-011634-index.htm

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