MIAX Institutional Ownership & Shareholders
MIAMI INTERNATIONAL HOLDINGS, INC. (MIAX) is currently held by 208 institutional investors tracked by InsiderSet, with a combined reported market value of approximately $2.63B based on the latest available SEC Form 13F filings for the quarter ended June 30, 2026.
Horizon Kinetics Asset Management Llc is currently the largest disclosed institutional shareholder of MIAX tracked by InsiderSet, reporting ownership valued at approximately $291.42M in its June 30, 2026 SEC Form 13F filing. Based on current market prices and the latest disclosed share count, the position is now estimated to be worth approximately $273.53M, representing an estimated loss of -6.14% since the filing period.
The top 10 institutional shareholders tracked on this page collectively account for approximately 50% of the total disclosed MIAX value among the investors covered in this analysis. Major shareholders include Horizon Kinetics Asset Management Llc, Blackrock, Inc., T. Rowe Price Investment Management, Inc., and several other long-term asset managers with concentrated positions in MIAMI INTERNATIONAL HOLDINGS, INC. (MIAX).
This page ranks the largest institutional MIAX shareholders using publicly disclosed SEC Form 13F data, including reported values, estimated current holding values, portfolio allocation percentages, ownership concentration metrics, and historical holding changes across major hedge funds and investment firms.
Institutional Holders
208
Total Reported Value
$2.63B
Largest Holder
Horizon Kinetics Asset Management Llc
Largest Position
$291.42M
Insider Transactions (90d)
4
Latest Filing Quarter
Q2 2026
New Institutional Positions
98
Funds Exiting Positions
0
| Name | Investor/Manager | Portfolio % | Quantity | Reported Balance | Current Estimated Value | Gain/loss Since Filing | Estimated Portfolio Performance |
|---|---|---|---|---|---|---|---|
| Horizon Kinetics Asset Management Llc | 3.30% | 7,842,173 | $291,415,166 | $273,534,994 | -$17,880,172 | -6.14% | |
| Blackrock, Inc. | 0.00% | 5,071,754 | $188,466,378 | $176,902,780 | -$11,563,598 | -6.14% | |
| T. Rowe Price Investment Management, Inc. | 0.12% | 5,032,970 | $187,026,000 | $175,549,994 | -$11,476,006 | -6.14% | |
| Vanguard Portfolio Management Llc | 0.01% | 3,786,418 | $140,703,293 | $132,070,260 | -$8,633,033 | -6.14% | |
| Susquehanna International Group, Llp | 0.11% | 3,355,043 | $124,673,398 | $117,023,900 | -$7,649,498 | -6.14% | |
| Vanguard Capital Management Llc | 0.00% | 3,165,686 | $117,636,892 | $110,419,128 | -$7,217,764 | -6.14% | |
| Invesco Ltd. | 0.01% | 2,020,650 | $75,087,354 | $70,480,272 | -$4,607,082 | -6.14% | |
| J Digital 6 Llc | 39.72% | 1,807,234 | $67,156,815 | $63,036,322 | -$4,120,493 | -6.14% | |
| Blair William & Co/Il | 0.17% | 1,769,432 | $65,752,093 | $61,717,788 | -$4,034,305 | -6.14% | |
| Balyasny Asset Management L.P. | 0.11% | 1,682,924 | $62,537,456 | $58,700,389 | -$3,837,067 | -6.14% | |
| American Century Companies Inc | 0.03% | 1,587,196 | $58,980,261 | $55,361,396 | -$3,618,865 | -6.14% | |
| State Street Corp | 0.00% | 1,432,894 | $53,246,341 | $49,979,343 | -$3,266,998 | -6.14% | |
| Jpmorgan Chase & Co | 0.00% | 1,427,881 | $52,718,389 | $49,804,489 | -$2,913,900 | -5.53% | |
| Geode Capital Management, Llc | 0.00% | 1,395,680 | $51,869,678 | $48,681,318 | -$3,188,360 | -6.15% | |
| Adage Capital Partners Gp, L.L.C. | 0.06% | 1,143,920 | $42,508,067 | $39,899,930 | -$2,608,137 | -6.14% | |
| Healthcare Of Ontario Pension Plan Trust Fund | 0.06% | 1,039,449 | $38,625,925 | $36,255,981 | -$2,369,944 | -6.14% | |
| Lord, Abbett & Co. Llc | 0.11% | 1,000,866 | $37,192,000 | $34,910,206 | -$2,281,794 | -6.14% | |
| Morgan Stanley | 0.00% | 950,593 | $35,324,037 | $33,156,684 | -$2,167,353 | -6.14% | |
| Allspring Global Investments Holdings, Llc | 0.05% | 857,682 | $33,492,482 | $29,915,948 | -$3,576,534 | -10.68% | |
| Two Sigma Investments, Lp | 0.02% | 888,109 | $33,002,130 | $30,977,242 | -$2,024,888 | -6.14% | |
| Bank Of America Corp | 0.00% | 856,980 | $31,845,377 | $29,891,462 | -$1,953,915 | -6.14% | |
| Alyeska Investment Group, L.P. | 0.08% | 848,750 | $31,539,550 | $29,604,400 | -$1,935,150 | -6.14% | |
| Price T Rowe Associates Inc | 0.00% | 844,464 | $31,381,000 | $29,454,904 | -$1,926,096 | -6.14% | |
| Walleye Capital Llc | 0.13% | 728,034 | $27,053,743 | $25,393,826 | -$1,659,917 | -6.14% | |
| Westfield Capital Management Co Lp | 0.09% | 700,741 | $26,039,536 | $24,441,846 | -$1,597,690 | -6.14% | |
| Newedge Advisors, Llc | 0.08% | 681,610 | $25,328,627 | $23,774,557 | -$1,554,070 | -6.14% | |
| Nuveen, Llc | 0.01% | 668,115 | $24,827,154 | $23,303,851 | -$1,523,303 | -6.14% | |
| Caldwell Investment Management Ltd. | 14.63% | 600,000 | $22,279,367 | $20,928,000 | -$1,351,367 | -6.07% | |
| Ubs Group Ag | 0.00% | 567,797 | $21,099,336 | $19,804,759 | -$1,294,577 | -6.14% | |
| Driehaus Capital Management Llc | 0.12% | 566,052 | $21,034,492 | $19,743,894 | -$1,290,598 | -6.14% | |
| Northern Trust Corp | 0.00% | 562,337 | $20,896,443 | $19,614,315 | -$1,282,128 | -6.14% | |
| Ameriprise Financial Inc | 0.00% | 559,485 | $20,790,462 | $19,514,837 | -$1,275,625 | -6.14% | |
| Seven Grand Managers, Llc | 0.82% | 550,000 | $20,438,000 | $19,184,000 | -$1,254,000 | -6.14% | |
| Ghisallo Capital Management Llc | 0.36% | 500,000 | $18,580,000 | $17,440,000 | -$1,140,000 | -6.14% | |
| Clearstead Advisors, Llc | 0.17% | 473,937 | $17,611,499 | $16,530,923 | -$1,080,576 | -6.14% | |
| Royce & Associates Lp | 0.14% | 452,813 | $16,826,531 | $15,794,117 | -$1,032,414 | -6.14% | |
| Victory Capital Management Inc | 0.01% | 427,425 | $15,883,113 | $14,908,584 | -$974,529 | -6.14% | |
| Massachusetts Financial Services Co | 0.00% | 406,274 | $15,097,142 | $14,170,837 | -$926,305 | -6.14% | |
| Goldman Sachs Group Inc | 0.00% | 399,844 | $14,858,203 | $13,946,559 | -$911,644 | -6.14% | |
| Bnp Paribas Financial Markets | 0.01% | 394,688 | $14,666,606 | $13,766,717 | -$899,889 | -6.14% | |
| Charles Schwab Investment Management Inc | 0.00% | 373,541 | $13,880,784 | $13,029,110 | -$851,674 | -6.14% | |
| Allianz Asset Management Gmbh | 0.01% | 359,261 | $13,350,139 | $12,531,024 | -$819,115 | -6.14% | |
| D. E. Shaw & Co., Inc. | 0.01% | 355,528 | $13,211,421 | $12,400,817 | -$810,604 | -6.14% | |
| Tocqueville Asset Management L.P. | 0.17% | 338,225 | $12,568,441 | $11,797,288 | -$771,153 | -6.14% | |
| Vanguard Fiduciary Trust Co | 0.00% | 315,336 | $11,717,886 | $10,998,920 | -$718,966 | -6.14% | |
| Sei Investments Co | 0.01% | 307,062 | $11,410,378 | $10,710,323 | -$700,055 | -6.14% | |
| Barclays Plc | 0.00% | 295,775 | $10,991,000 | $10,316,632 | -$674,368 | -6.14% | |
| Burkehill Global Management, Lp | 0.39% | 290,000 | $10,776,400 | $10,115,200 | -$661,200 | -6.14% | |
| Marshall Wace, Llp | 0.01% | 287,480 | $10,682,756 | $10,027,302 | -$655,454 | -6.14% | |
| Langdon Equity Partners | 5.87% | 282,500 | $10,497,700 | $9,853,600 | -$644,100 | -6.14% |
Frequently asked questions about MIAX
Who are the largest institutional holders of MIAX?
The largest institutional holders of MIAX reported in the latest SEC Form 13F filings include Horizon Kinetics Asset Management Llc, Blackrock, Inc., T. Rowe Price Investment Management, Inc., Vanguard Portfolio Management Llc, and Susquehanna International Group, Llp. InsiderSet ranks institutional holders by their latest reported MIAX position.
What is MIAX institutional ownership?
This page tracks MIAX positions reported by institutional investment managers through SEC Form 13F. MIAMI INTERNATIONAL HOLDINGS, INC. (MIAX) institutional ownership on InsiderSet reflects disclosed 13F holdings among the managers we analyze, not every shareholder of the stock.
How many institutions own MIAX?
InsiderSet currently tracks 208 institutional managers reporting MIAX holdings in the latest available 13F data. This count reflects institutions included in the SEC Form 13F filings analyzed by InsiderSet and should not be interpreted as the total number of MIAX shareholders.
How much MIAX stock do institutions own?
Institutional investment managers disclosed approximately $2.63B in MIAX holdings for Q2 2026. This figure is reported 13F value as of the filing period, not necessarily today's market value.
When was MIAX institutional ownership last updated?
The latest MIAX institutional ownership data on InsiderSet is based on SEC Form 13F filings for the quarter ended June 30, 2026. Form 13F filings are generally reported after the quarter ends, so the holdings shown represent the latest publicly disclosed positions rather than real-time institutional holdings.
Are institutional MIAX holdings real-time?
No. Form 13F data is not real-time. It represents positions reported by institutional investment managers as of the end of the reporting quarter. An institution may have changed its MIAX position after the reporting date.
Are institutions buying or selling MIAX?
Institutional buying and selling can be analyzed by comparing MIAX positions across consecutive 13F reporting periods. InsiderSet's MIAX Ownership Changes page shows institutions that increased, reduced, initiated, or exited positions based on reported 13F holdings. View MIAX ownership changes.
How has MIAX institutional ownership changed over time?
InsiderSet tracks MIAX institutional holdings across multiple 13F reporting periods, allowing investors to compare institutional holder counts, reported value, and reported shares over time.