MIAX Miami International Holdings, Inc.
Miami International Holdings, Inc. (MIAX) Insider Activity
What the officers, directors and large holders did with their own shares. Only open-market purchases and sales count toward the totals — grants, option exercises and shares withheld for tax are compensation mechanics, not decisions, and they're listed separately below.
How much of that selling was preplanned? 98% planned / 2% discretionary
Largest single sale: $6.2M.
Where they traded
Last open-market purchase: March 5, 2026 .
Recent open-market activity
| Date | Insider | Role | Action | Shares | Price | Value | Held after |
|---|---|---|---|---|---|---|---|
| Gallagher Thomas P. | Chairman & CEO | Sell 10b5-1 | 47,000 | $42.43 | $2.0M | 1,423,275 −3.2% of holding | |
| Deitzel Edward | EVP, CRO, CCO MIAX Exchanges | Sell 10b5-1 | 11,000 | $42.21 | $464.3K | 119,601 −8.4% of holding | |
| Schafer Douglas M. JR | EVP and CIO | Sell 10b5-1 | 48,000 | $40.48 | $1.9M | 387,414 −11% of holding | |
| Comly Barbara J. | EVP, GC & Corporate Secretary | Sell 10b5-1 | 44,445 | $40.49 | $1.8M | 839,564 −5% of holding | |
| Teekell Judson Gray | Director | Sell | 5,545 | $41.58 | $230.6K | 81,000 −6.4% of holding | |
| Teekell Judson Gray | Director | Sell 10b5-1 | 3,000 | $40.89 | $122.7K | 69,251 −4.2% of holding | |
| Gallagher Thomas P. | Chairman & CEO | Sell 10b5-1 | 149,700 | $41.13 | $6.2M | 1,423,275 −9.5% of holding | |
| Emmons Lance | EVP and CFO | Sell 10b5-1 | 35,000 | $42.83 | $1.5M | 86,538 −28.8% of holding | |
| Schwarzkopf Cynthia | Director | Sell 10b5-1 | 5,000 | $42.85 | $214.3K | 88,545 −5.3% of holding |
Form 4s are due within two business days of a transaction, so this is close to real time — unlike the quarterly 13F data on the Institutional tab. A single large sale often reflects a prearranged 10b5-1 plan rather than a fresh view, so read a pattern of sales rather than any one of them.