MIAMI INTERNATIONAL (MIAX) EVP Douglas M. Schafer Jr Exercises Options, Sells Shares

What Happened
Douglas M. Schafer Jr, Executive Vice President & Chief Investment Officer of Miami International Holdings (MIAX), exercised 48,000 stock options at a $12.00 strike (cost $576,000) and sold 48,000 shares in an open-market transaction for a weighted average price of $45.71, generating gross proceeds of approximately $2,194,080. The exercise and sale occurred on August 4, 2026 and were reported on a Form 4 filed August 6, 2026. The filing also reports a separate derivative conversion/disposition of 48,000 shares at $0.00 (reported as a derivative entry).

Key Details

• Transaction date: August 4, 2026; Form 4 filed August 6, 2026 (timely filing).
• Exercise: 48,000 shares at $12.00 per share — total cost $576,000.
• Sale: 48,000 shares sold on-market; weighted average sale price $45.71; gross proceeds ≈ $2,194,080. Trades occurred across prices $45.09–$46.78 (weighted avg reported).
• Net proceeds (approx.): $2,194,080 − $576,000 = ~$1,618,080 before taxes/fees.
• Footnotes: Transaction executed under a previously established Rule 10b5-1 plan adopted Dec 16, 2025 (F1); multiple trades/prices underlying weighted average are available on request (F2); the options were fully vested (F3).
• Shares owned after transaction: Not stated in this filing.

Context

• This was effectively a same-day exercise and sale (cashless-style outcome): Schafer exercised vested options and sold the resulting shares the same day. Such transactions are commonly used to realize gains and cover exercise costs and taxes.
• The sale was executed under a pre-established 10b5-1 plan, which typically schedules trades in advance and is intended to avoid concerns about trading on material nonpublic information.
• The filing is factual and does not indicate the insider’s personal view of MIAX’s prospects.