---
schema_version: "secwatch.filing_event.v1"
accession: "0001193125-23-133205"
form_type: "8-K"
ticker: "DNTH"
cik: "0001690585"
company_name: "Dianthus Therapeutics, Inc. /DE/"
filed_at: "2023-05-03T23:59:59+00:00"
generated_at: "2026-06-16T01:13:22.915004+00:00"
event_type: "m_and_a"
sentiment: "neutral"
materiality_score: 0.9
calibrated_materiality_score: 0.9
confidence: "high"
source: SEC EDGAR
---

# Magenta to merge with Dianthus in reverse merger; Dianthus holders to own 78.7% of combined firm

## Summary
- Dianthus stockholders will own ~78.7% of combined company; Magenta holders ~21.3%.
- Concurrent $70M private placement of Dianthus shares and pre-funded warrants closing pre-merger.
- Magenta holders get one CVR per share tied to net proceeds from legacy asset sales by Dec 31, 2023.
- Magenta CEO and board largely replaced; 6 of 8 board members designated by Dianthus.
- Termination fee of $13.3M payable by either party under specified conditions.

## SEC filing metadata
- accession: 0001193125-23-133205
- form_type: 8-K
- ticker: DNTH
- cik: 0001690585
- company_name: Dianthus Therapeutics, Inc. /DE/
- filed_at: 2023-05-03T23:59:59+00:00
- event_type: m_and_a
- sentiment: neutral
- materiality_score: 0.9
- calibrated_materiality_score: 0.9
- confidence: high
- sec_items: 1.01, 3.02, 3.03, 5.01, 5.02, 7.01, 9.01
- EDGAR index: https://www.sec.gov/Archives/edgar/data/1690585/000119312523133205/0001193125-23-133205-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/1690585/000119312523133205/d503643d8k.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0001193125-23-133205
- JSON: https://secwatch.observer/filing/0001193125-23-133205.json
- Plain text: https://secwatch.observer/filing/0001193125-23-133205.txt

## Key facts
- Material Agreements
  Dianthus Therapeutics, Inc. /DE/ entered into Agreement and Plan of Merger with Magenta Therapeutics, Inc. (effective 2023-05-02).
  - Action: entry
  - Agreement: merger
  - Counterparty: Magenta Therapeutics, Inc.
  - Effective: 2023-05-02
  source text: On May 2, 2023, Magenta Therapeutics, Inc., a Delaware corporation (“Magenta”), Dio Merger Sub, Inc., a Delaware corporation and a wholly owned subsidiary of Magenta (“Merger Sub”), and Dianthus Therapeutics, Inc., a Delaware corporation (“Dianthus”), entered into an Agreement and Plan of Merger (the “Merger Agreement”)
  evidence_url: https://www.sec.gov/Archives/edgar/data/1690585/000119312523133205/0001193125-23-133205-index.htm

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