---
schema_version: "secwatch.filing_event.v1"
accession: "0001628280-25-057039"
form_type: "8-K"
ticker: "MIAX"
cik: "0001438472"
company_name: "MIAMI INTERNATIONAL HOLDINGS, INC."
filed_at: "2025-12-15T23:59:59+00:00"
generated_at: "2026-05-16T13:12:18.794861+00:00"
event_type: "other_material"
sentiment: "neutral"
materiality_score: 0.7
calibrated_materiality_score: 0.7
confidence: "high"
source: SEC EDGAR
---

# Miami International Holdings secondary offering of 6.75M shares by stockholders; 4M shares issued unregistered

## Summary
- Existing stockholders sold 6,750,000 shares in secondary offering at $41.00 per share; company received no proceeds.
- Underwriters fully exercised option to purchase an additional 1,012,500 shares at $41.00 each.
- Company issued 4,006,946 shares of common stock through conversions of a $5,000,000 convertible note and warrant exercises since September 30, 2025.
- Conversions included 317,787 shares from principal plus interest on the $5 million note at $16.00 per share.
- Warrant exercises yielded $2,419,500 cash and surrender of 733,923 shares via cashless exercises.

## SEC filing metadata
- accession: 0001628280-25-057039
- form_type: 8-K
- ticker: MIAX
- cik: 0001438472
- company_name: MIAMI INTERNATIONAL HOLDINGS, INC.
- filed_at: 2025-12-15T23:59:59+00:00
- event_type: other_material
- sentiment: neutral
- materiality_score: 0.7
- calibrated_materiality_score: 0.7
- confidence: high
- sec_items: 3.02, 8.01
- EDGAR index: https://www.sec.gov/Archives/edgar/data/1438472/000162828025057039/0001628280-25-057039-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/1438472/000162828025057039/miax-20251215.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0001628280-25-057039
- JSON: https://secwatch.observer/filing/0001628280-25-057039.json
- Plain text: https://secwatch.observer/filing/0001628280-25-057039.txt

## Key facts
- Equity Issuances
  MIAMI INTERNATIONAL HOLDINGS, INC. issued 317,787 shares of common stock for Conversion of a convertible promissory note in the principal amount of $5,000,000, plus accrued but unpaid interest thereunder at a price per share of $16.00.
  - Security: common stock
  - Shares: 317,787 shares
  - Consideration: Conversion of a convertible promissory note in the principal amount of $5,000,000, plus accrued but unpaid interest thereunder at a price per share of $16.00
  source text: Common Stock 12/4/2025 317,787 Conversion of a convertible promissory note in the principal amount of $5,000,000, plus accrued but unpaid interest thereunder at a price per share of $16.00.
  evidence_url: https://www.sec.gov/Archives/edgar/data/1438472/000162828025057039/0001628280-25-057039-index.htm
- Equity Issuances
  MIAMI INTERNATIONAL HOLDINGS, INC. issued 3,522,102 shares of common stock to certain of the Company's holders for $2,419,500 plus surrender of an aggregate of 698,521 shares of Common Stock pursuant to cashless exercise of warrants.
  - Security: common stock
  - Shares: 3,522,102 shares
  - Purchaser: certain of the Company's holders
  - Consideration: $2,419,500 plus surrender of an aggregate of 698,521 shares of Common Stock pursuant to cashless exercise of warrants
  source text: Common Stock 12/12/2025 3,522,102 $2,419,500 plus surrender of an aggregate of 698,521 shares of Common Stock pursuant to cashless exercise of warrants
  evidence_url: https://www.sec.gov/Archives/edgar/data/1438472/000162828025057039/0001628280-25-057039-index.htm
- Equity Issuances
  MIAMI INTERNATIONAL HOLDINGS, INC. issued 7,483 shares of common stock for Conversion of $119,726 worth of accrued but unpaid interest under a convertible promissory note at a price per share of $16.00.
  - Security: common stock
  - Shares: 7,483 shares
  - Consideration: Conversion of $119,726 worth of accrued but unpaid interest under a convertible promissory note at a price per share of $16.00
  source text: Common Stock 10/1/2025 7,483 Conversion of $119,726 worth of accrued but unpaid interest under a convertible promissory note at a price per share of $16.00.
  evidence_url: https://www.sec.gov/Archives/edgar/data/1438472/000162828025057039/0001628280-25-057039-index.htm

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