M
Miami International Holdings, Inc.
MIAX • NYSE
Miami International Holdings, Inc. is a publicly traded company on NYSE, led by Thomas Gallagher, with a market cap of $3.6B. As of Q3 2025, 31% of shares are held by 113 institutional investors, with SUSQUEHANNA INTERNATIONAL GROUP, LLP as the largest holder at 4.02%.
CEOThomas Gallagher
Market Cap$3.6B
Overview
Overview of institutional ownership in MIAX as of Q3 2025 with a market cap of $3.3B
All Institutions
- Institutions
- 113
- Value Held
- $1.0B
- Shares Held
- 25.5M
- Avg Position
- $9.1M
- Median Position
- $2.0M
Hedge Funds
- Hedge Funds
- 34
- Value Held
- $252.7M
- Shares Held
- 6.3M
- Avg Position
- $7.4M
- Median Position
- $3.6M
Ownership Breakdown
Based on market cap of $3.3B as of Q3 2025. Institutional (non-HF) excludes hedge funds to avoid double counting.
Biggest Investors
Institutions with the largest positions in MIAX as of Q3 2025
| Institution | Position Value |
|---|---|
 SUSQUEHANNA INTERNATIONAL GROUP, LLP Private Equity | $132.2M 0.19% of portfolio |
T T. Rowe Price Investment Management, Inc. Insurance Manager | $97.9M 0.06% of portfolio |
 VANGUARD GROUP INC Institution | $55.7M 0.00% of portfolio |
 HORIZON KINETICS ASSET MANAGEMENT LLC Long Only Manager | $55.7M 0.68% of portfolio |
A Alyeska Investment Group, L.P. Hedge Fund•Multi-Strategy | $51.0M 0.15% of portfolio |
 CITADEL ADVISORS LLC Hedge Fund•Multi-Strategy | $39.3M 0.03% of portfolio |
 JPMORGAN CHASE & CO Institution | $32.7M 0.00% of portfolio |
N North Reef Capital Management LP Hedge Fund•Long/Short | $29.2M 1.37% of portfolio |
 BlackRock, Inc. Institution | $28.5M 0.00% of portfolio |
 Caldwell Investment Management Ltd. RIA/Wealth | $27.1M 20.19% of portfolio |
Net Capital Flow
Institutional buying and selling activity for MIAX in Q3 2025
- Traded
- +$1.0B
- Buyers
- 113
- Sellers
- 0
- Total Bought
- +$1.0B
- Total Sold
- −-
- Avg Position
- $8.9M
Biggest Buyers
| Institution | Net Bought |
|---|---|
SUSQUEHANNA INTERNATIONAL GROUP, LLP Private Equity | +$132.2M +3.3M shares |
T T. Rowe Price Investment Management, Inc. Insurance Manager | +$97.9M +2.4M shares |
VANGUARD GROUP INC Institution | +$55.7M +1.4M shares |
HORIZON KINETICS ASSET MANAGEMENT LLC Long Only Manager | +$55.7M +1.4M shares |
A Alyeska Investment Group, L.P. Hedge Fund•Multi-Strategy | +$51.0M +1.3M shares |
CITADEL ADVISORS LLC Hedge Fund•Multi-Strategy | +$39.3M +975.1K shares |
JPMORGAN CHASE & CO Institution | +$32.7M +811.7K shares |
N North Reef Capital Management LP Hedge Fund•Long/Short | +$29.2M +725.8K shares |
BlackRock, Inc. Institution | +$28.5M +707.8K shares |
Caldwell Investment Management Ltd. RIA/Wealth | +$27.1M +663.8K shares |
Biggest Sellers
| Institution | Net Sold | |
|---|---|---|
| No sellers found | ||
Entry and Exit Activity
Institutions that initiated new positions or completely exited MIAX in Q3 2025
- New Positions
- 115
- New Value
- $1.0B
- Exited Positions
- 1
- Exited Value
- -
New Positions
| Institution | Position Value |
|---|---|
SUSQUEHANNA INTERNATIONAL GROUP, LLP Private Equity | $132.2M 3.3M shares |
T T. Rowe Price Investment Management, Inc. Insurance Manager | $97.9M 2.4M shares |
VANGUARD GROUP INC Institution | $55.7M 1.4M shares |
HORIZON KINETICS ASSET MANAGEMENT LLC Long Only Manager | $55.7M 1.4M shares |
A Alyeska Investment Group, L.P. Hedge Fund•Multi-Strategy | $51.0M 1.3M shares |
CITADEL ADVISORS LLC Hedge Fund•Multi-Strategy | $39.3M 975.1K shares |
JPMORGAN CHASE & CO Institution | $32.7M 811.7K shares |
N North Reef Capital Management LP Hedge Fund•Long/Short | $29.2M 725.8K shares |
BlackRock, Inc. Institution | $28.5M 707.8K shares |
Caldwell Investment Management Ltd. RIA/Wealth | $27.1M 663.8K shares |
Exited Positions
| Institution | Previous Position |
|---|---|
N NOMURA ASSET MANAGEMENT CO LTD Long Only Manager | - - shares |
Options Activity
Institutions with the largest Call and Put options positions in MIAX as of Q3 2025
- Call Positions
- 4
- Call Value
- $9.8M
- Put Positions
- 5
- Put Value
- $5.8M
Call Positions
| Institution | Position Value |
|---|---|
SUSQUEHANNA INTERNATIONAL GROUP, LLP Private Equity | $5.2M 1.3K contracts |
J JANE STREET GROUP, LLC Institution | $2.2M 554.0 contracts |
CITADEL ADVISORS LLC Hedge Fund•Multi-Strategy | $1.9M 480.0 contracts |
W WOLVERINE TRADING, LLC Institution | $407.7K 100.0 contracts |
Put Positions
| Institution | Position Value |
|---|---|
SUSQUEHANNA INTERNATIONAL GROUP, LLP Private Equity | $2.7M 679.0 contracts |
CITADEL ADVISORS LLC Hedge Fund•Multi-Strategy | $1.4M 341.0 contracts |
 ExodusPoint Capital Management, LP Hedge Fund•Multi-Strategy | $999.5K 250.0 contracts |
J JANE STREET GROUP, LLC Institution | $382.5K 95.0 contracts |
W WOLVERINE TRADING, LLC Institution | $293.5K 72.0 contracts |
Most Committed Institutions
Institutions with MIAX as the highest % of their portfolio as of Q3 2025
| Institution | Portfolio Weight |
|---|---|
Caldwell Investment Management Ltd. RIA/Wealth | 20.19% $27.1M |
 Monashee Investment Management LLC Hedge Fund•Sector | 3.25% $6.0M |
 Intrinsic Edge Capital Management LLC Hedge Fund•Multi-Strategy | 2.13% $14.0M |
N North Reef Capital Management LP Hedge Fund•Long/Short | 1.37% $29.2M |
 MRM-Horizon Advisors LLC Fund of Funds | 1.29% $3.0M |
 SANDLER ONEILL ASSET MANAGEMENT LLC Hedge Fund•Long/Short | 1.00% $6.4M |
S SEVEN GRAND MANAGERS, LLC Hedge Fund•Multi-Strategy | 0.96% $12.1M |
 Sandia Investment Management LP Hedge Fund•Event Driven | 0.90% $265.7K |
 Atlas Wealth Partners, LLC RIA/Wealth | 0.90% $881.3K |
S SALT Holding Corp. Institution | 0.77% $610.9K |
Hedge Fund Spotlight
Discover hedge funds investing in MIAX
TUDOR INVESTMENT CORP ET AL
Hedge Fund • Multi-Strategy
Portfolio ManagerMichael Riccardi
- Portfolio Value
- $16.0B
- Positions
- 1,517
- Last Reported
- Q3 2025
Sector Allocation
M
Position in Miami International Holdings, Inc.
- Market Value
- $1.8M
- Shares Held
- 45.5K
- Portfolio Weight
- 0.01%
- Owned Since
- 2025-Q3
| Top Holding | Sector | Market Value | Weight |
|---|---|---|---|
ETF ETF | $968.5M | 6.05% | |
ETF ETF | $344.0M | 2.15% | |
Semiconductors Technology | $219.5M | 1.37% |
