---
schema_version: "secwatch.filing_event.v1"
accession: "0001193125-25-177597"
form_type: "8-K"
ticker: null
cik: "0001764974"
company_name: "Turnstone Biologics Corp."
filed_at: "2025-08-11T23:59:59+00:00"
generated_at: "2026-05-17T15:35:39.777230+00:00"
event_type: "m_and_a"
sentiment: "neutral"
materiality_score: 0.9
calibrated_materiality_score: 0.9
confidence: "high"
source: SEC EDGAR
---

# Turnstone Biologics completes acquisition by XOMA Royalty for $0.34/share plus CVR

## Summary
- Merger closed Aug 11, 2025; shareholders get $0.34 cash plus one non-transferable CVR per share.
- 17,192,002 shares (≈74% of outstanding) tendered; all conditions satisfied; no shareholder vote required.
- CVR may pay up to ~$1.1M from Canadian tax refunds and sublease security deposit within 12 months.
- Asset sale to Moffitt Cancer Center closed for ~$3.0M total consideration; $1.8M in escrow initially.
- All Turnstone directors resigned; Owen Hughes became sole director/officer of surviving corporation.

## SEC filing metadata
- accession: 0001193125-25-177597
- form_type: 8-K
- cik: 0001764974
- company_name: Turnstone Biologics Corp.
- filed_at: 2025-08-11T23:59:59+00:00
- event_type: m_and_a
- sentiment: neutral
- materiality_score: 0.9
- calibrated_materiality_score: 0.9
- confidence: high
- sec_items: 2.01, 3.01, 3.03, 5.01, 5.02, 5.03, 9.01
- EDGAR index: https://www.sec.gov/Archives/edgar/data/1764974/000119312525177597/0001193125-25-177597-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/1764974/000119312525177597/d27108d8k.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0001193125-25-177597
- JSON: https://secwatch.observer/filing/0001193125-25-177597.json
- Plain text: https://secwatch.observer/filing/0001193125-25-177597.txt

## Key facts
- Governance Changes
  Turnstone Biologics Corp.: Certificate of incorporation amended and restated in its entirety following merger.
  - Change: charter amendment
  source text: (i) the Surviving Corporation’s certificate of incorporation was amended and restated in its entirety, as set forth in Exhibit 3.1 to this Current Report on Form 8-K and is incorporated herein by reference
  evidence_url: https://www.sec.gov/Archives/edgar/data/1764974/000119312525177597/0001193125-25-177597-index.htm
- Governance Changes
  Turnstone Biologics Corp.: Bylaws of Merger Sub became the bylaws of the Surviving Corporation following merger.
  - Change: bylaw amendment
  source text: (ii) the bylaws of Merger Sub as in effect immediately prior to the Effective Time became the bylaws of the Surviving Corporation, as set forth in Exhibit 3.2 to this Current Report on Form 8-K and is incorporated herein by reference
  evidence_url: https://www.sec.gov/Archives/edgar/data/1764974/000119312525177597/0001193125-25-177597-index.htm
- M&A Transactions
  Turnstone Biologics Corp. completed a disposition involving H. Lee Moffitt Cancer Center and Research Institute, Inc for total consideration of approximately $3.0 million to offset Turnstone’s obligations to Moffitt under the Alliance Agreement, of which, approximately $1.8 millio (closed 2025-08-11).
  - Action: disposition
  - Counterparty: H. Lee Moffitt Cancer Center and Research Institute, Inc
  - Consideration: total consideration of approximately $3.0 million to offset Turnstone’s obligations to Moffitt under the Alliance Agreement, of which, approximately $1.8 millio
  - Closing: 2025-08-11
  source text: certain obligations of the Company’s under the Myst Merger Agreement (as defined in the Asset Purchase Agreement). Turnstone received a total consideration of approximately $3.0 million to offset Turnstone’s obligations to Moffitt under the Alliance Agreement (as defined in the Asset Purchase Agreement), of which, approximately $1.8 million was placed into an
  evidence_url: https://www.sec.gov/Archives/edgar/data/1764974/000119312525177597/0001193125-25-177597-index.htm
- M&A Transactions
  Turnstone Biologics Corp. underwent a change of control involving XOMA Royalty Corporation for per Share of (i) $0.34 cash plus (ii) one non-transferable contractual contingent value right (CVR) representing potential additional cash payments (closed 2025-08-11).
  - Action: change of control
  - Counterparty: XOMA Royalty Corporation
  - Consideration: per Share of (i) $0.34 cash plus (ii) one non-transferable contractual contingent value right (CVR) representing potential additional cash payments
  - Closing: 2025-08-11
  source text: Purchaser completed a tender offer to purchase all of the Company’s outstanding shares of common stock, par value $0.001 per share (the “Shares”), for a price per Share of (i) $0.34 (the “Cash Amount”), payable subject to any applicable tax withholding and without interest, plus (ii) one non-transferable contractual contingent value right (“CVR”), which shall
  evidence_url: https://www.sec.gov/Archives/edgar/data/1764974/000119312525177597/0001193125-25-177597-index.htm

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