Miami International Holdings MIAX Institutional Ownership

NYSE MIAX

$33.95 +0.45 (+1.34%)

As of: Oct 1, 2026 · 2:17 PM EDT

Institutions by Trading Activity

209 Institutions

Increased 143 68.4%

Unchanged 20 9.6%

Reduced 46 22.0%

Ownership Statistics

13F · as of 30 Jun, 2026

Institutional Ownership

75.68%

▲+20.79 pp QoQ

Shares Held by Institutions

72.13Mn

of 95.31Mn outstanding

▲+57.00% QoQ

Shares Outstanding

95.31Mn

23.18Mn held outside 13F filers

Institutional Investors

209

filed 13F for Jun 2026

▲+8 vs prior quarter

Net Shares Added (QoQ)

+26.19Mn

accumulated since last quarter

Value of Holdings

$2.42Bn

reported market value

Shares Owned by Institutions

Shares held % of outstanding

Latest —

Average ownership —

Peak ownership —

Shares Purchased/Sold by Institutions

Accumulated Distributed

Latest quarter —

Net over range —

Accumulating quarters —

Ownership Summary

Quarter ending 30 Jun, 2026

Miami International Holdings, Inc. (NYSE:MIAX) showed up in the 13F filings of 209 institutional investors as of June 2026.

Collectively, these holders controlled 75.7% of Miami International Holdings's outstanding shares in June 2026, up from 54.9% in March 2026.
Their total shares held in MIAX increased 57.0% from the prior quarter, while the number of investors in Miami International Holdings stayed flat year over year.
During the quarter, 143 of these 209 funds increased positions in MIAX, 46 reduced exposure, and 20 held steady.
In total, institutional investors held 72.13Mn shares in Miami International Holdings as of June 2026, up by 26.19Mn shares quarter on quarter, and with no net change year over year.
HORIZON KINETICS ASSET MANAGEMENT LLC holds the largest position in MIAX at 7.84Mn shares as of June 30, 2026, or 8.23% of shares outstanding.
Top purchasers of MIAX stock for the quarter ending June 2026 included HORIZON KINETICS ASSET MANAGEMENT LLC (4.39Mn), BlackRock, Inc. (2.84Mn), VANGUARD PORTFOLIO MANAGEMENT LLC (2.41Mn), J Digital 6 LLC (1.81Mn), VANGUARD CAPITAL MANAGEMENT LLC (1.75Mn).
Leading sellers of Miami International Holdings shares for the quarter ending June 2026 were North Reef Capital Management LP (762.92K), Alyeska Investment Group, L.P. (598.7K), Ghisallo Capital Management LLC (500.0K), MILLENNIUM MANAGEMENT LLC (329.6K), Allspring Global Investments Holdings, LLC (254.58K).
Per Business Quant data, the top 10 holders of Miami International Holdings for the quarter ending June 2026 are HORIZON KINETICS ASSET MANAGEMENT LLC (7.84Mn), BlackRock, Inc. (5.07Mn), T. Rowe Price Investment Management, Inc. (5.03Mn), VANGUARD PORTFOLIO MANAGEMENT LLC (3.79Mn), SUSQUEHANNA INTERNATIONAL GROUP, LLP (3.36Mn), VANGUARD CAPITAL MANAGEMENT LLC (3.17Mn), Invesco Ltd. (2.02Mn), J Digital 6 LLC (1.81Mn), BLAIR WILLIAM & CO/IL (1.77Mn), BALYASNY ASSET MANAGEMENT L.P. (1.68Mn).

Form 13F Holdings

209 Institutional Holders

Report period 30 Jun, 2026

Total shares held 72.13Mn

Of outstanding 75.68%

#	Institution	CIK	Shares Held	% of Outstanding	Change (QoQ)	Change (%)	Value (USD)
1	HORIZON KINETICS ASSET MANAGEMENT LLC	0001056823	7,842,173	8.23%	▲4,390,624	+127.21%	$291.42Mn
2	BlackRock, Inc.	0002012383	5,071,754	5.32%	▲2,839,074	+127.16%	$188.47Mn
3	T. Rowe Price Investment Management, Inc.	0001897612	5,032,970	5.28%	▲887,352	+21.40%	$187.03K
4	VANGUARD PORTFOLIO MANAGEMENT LLC	0002100121	3,786,418	3.97%	▲2,411,472	+175.39%	$140.70Mn
5	SUSQUEHANNA INTERNATIONAL GROUP, LLP	0001446194	3,355,043	3.52%	▲58,697	+1.78%	$124.67Mn
6	VANGUARD CAPITAL MANAGEMENT LLC	0002100119	3,165,686	3.32%	▲1,750,707	+123.73%	$117.64Mn
7	Invesco Ltd.	0000914208	2,020,650	2.12%	▲435,647	+27.49%	$75.09Mn
8	J Digital 6 LLC	0002090663	1,807,234	1.90%	▲1,807,234	0.00%	$67.16Mn
9	BLAIR WILLIAM & CO/IL	0000902367	1,769,432	1.86%	▲1,103,651	+165.77%	$65.75Mn
10	BALYASNY ASSET MANAGEMENT L.P.	0001218710	1,682,924	1.77%	▲1,682,924	0.00%	$62.54Mn
11	AMERICAN CENTURY COMPANIES INC	0000748054	1,587,196	1.67%	▲365,711	+29.94%	$58.98Mn
12	State Street Corp	0000093751	1,432,894	1.50%	▲720,565	+101.16%	$53.25Mn
13	Jpmorgan Chase & Co	0000019617	1,427,881	1.50%	▲189,875	+15.34%	$52.72Mn
14	GEODE CAPITAL MANAGEMENT, LLC	0001214717	1,395,680	1.46%	▲615,898	+78.98%	$51.87Mn
15	ADAGE CAPITAL PARTNERS GP, L.L.C.	0001165408	1,143,920	1.20%	▼103,079	-8.27%	$42.51Mn
16	HEALTHCARE OF ONTARIO PENSION PLAN TRUST FUND	0001535845	1,039,449	1.09%	▲799,449	+333.10%	$38.63Mn
17	LORD, ABBETT & CO. LLC	0000728100	1,000,866	1.05%	▲140,179	+16.29%	$37.19K
18	Morgan Stanley	0000895421	950,593	1.00%	▼196,363	-17.12%	$35.32Mn
19	TWO SIGMA INVESTMENTS, LP	0001179392	888,109	0.93%	▼5,609	-0.63%	$33.00Mn
20	Allspring Global Investments Holdings, LLC	0001890906	857,682	0.90%	▼254,579	-22.89%	$33.49Mn

Showing 1 to 20 of 209 holders