Miami International Holdings MIAX Institutional Ownership

NYSE MIAX

$44.04 +1.45 (+3.40%)

As of: Aug 24, 2026 · 3:59 PM EDT

Institutions by Trading Activity

199 Institutions

Increased 159 79.9%

Unchanged 12 6.0%

Reduced 28 14.1%

Ownership Statistics

13F · as of 31 Mar, 2026

Institutional Ownership

54.88%

▼-0.68 pp QoQ

Shares Held by Institutions

50.37Mn

of 91.79Mn outstanding

▲+45.00% QoQ

Shares Outstanding

91.79Mn

41.42Mn held outside 13F filers

Institutional Investors

199

filed 13F for Mar 2026

▲+38 vs prior quarter

Net Shares Added (QoQ)

+15.63Mn

accumulated since last quarter

Value of Holdings

$2.11Bn

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 31 Mar, 2026

Miami International Holdings, Inc. (NYSE:MIAX) has 199 institutional investors with active 13F positions as of March 2026.

They owned 54.9% of outstanding stock in March 2026, down from 55.6% the prior quarter.
Their total shares held in MIAX increased 45.0% quarter over quarter, and separately, investors owning Miami International Holdings stayed flat from a year ago.
Among the 199 funds, 159 bought more Miami International Holdings shares, 28 sold down, and 12 held their ground.
The aggregate institutional position in Miami International Holdings amounted to 50.37Mn shares as of March 2026, up by 15.63Mn shares quarter on quarter, and with no net change year over year.
As of March 31, 2026, T. Rowe Price Investment Management, Inc. held the largest stake in Miami International Holdings with 4.15Mn shares, accounting for 4.52% of total shares outstanding.
Top purchasers of MIAX stock for the quarter ending March 2026 included HORIZON KINETICS ASSET MANAGEMENT LLC (1.63Mn), VANGUARD CAPITAL MANAGEMENT LLC (1.41Mn), VANGUARD PORTFOLIO MANAGEMENT LLC (1.37Mn), CITADEL ADVISORS LLC (988.2K), Morgan Stanley (926.08K).
The biggest sellers of Miami International Holdings for the quarter ending March 2026 included Goldman Sachs Group Inc (735.02K), Delta Global Management LP (270.4K), Jump Financial, LLC (266.3K), North Reef Capital Management LP (250.73K), AMERICAN CENTURY COMPANIES INC (226.81K).
Business Quant data shows the 10 biggest positions in Miami International Holdings as of March 2026 are held by T. Rowe Price Investment Management, Inc. (4.15Mn), HORIZON KINETICS ASSET MANAGEMENT LLC (3.45Mn), SUSQUEHANNA INTERNATIONAL GROUP, LLP (3.3Mn), BlackRock, Inc. (2.23Mn), CITADEL ADVISORS LLC (1.61Mn), Invesco Ltd. (1.59Mn), Alyeska Investment Group, L.P. (1.45Mn), VANGUARD CAPITAL MANAGEMENT LLC (1.41Mn), VANGUARD PORTFOLIO MANAGEMENT LLC (1.37Mn), ADAGE CAPITAL PARTNERS GP, L.L.C. (1.25Mn).

Form 13F Holdings

199 Institutional Holders

Report period 31 Mar, 2026

Total shares held 50.37Mn

Of outstanding 54.88%

#	Institution	CIK	Shares Held	% of Outstanding	Change (QoQ)	Change (%)	Value (USD)
1	T. Rowe Price Investment Management, Inc.	0001897612	4,145,618	4.52%	▲609,879	+17.25%	$161.35K
2	HORIZON KINETICS ASSET MANAGEMENT LLC	0001056823	3,451,549	3.76%	▲1,631,751	+89.67%	$134.33Mn
3	SUSQUEHANNA INTERNATIONAL GROUP, LLP	0001446194	3,296,346	3.59%	▲11,394	+0.35%	$128.29Mn
4	BlackRock, Inc.	0002012383	2,232,680	2.43%	▲479,173	+27.33%	$86.90Mn
5	CITADEL ADVISORS LLC	0001423053	1,607,780	1.75%	▲988,200	+159.50%	$62.57Mn
6	Invesco Ltd.	0000914208	1,585,003	1.73%	▲306,037	+23.93%	$61.69Mn
7	Alyeska Investment Group, L.P.	0001453072	1,447,454	1.58%	▲161,368	+12.55%	$56.33Mn
8	VANGUARD CAPITAL MANAGEMENT LLC	0002100119	1,414,979	1.54%	▲1,414,979	0.00%	$55.07Mn
9	VANGUARD PORTFOLIO MANAGEMENT LLC	0002100121	1,374,946	1.50%	▲1,374,946	0.00%	$53.51Mn
10	ADAGE CAPITAL PARTNERS GP, L.L.C.	0001165408	1,246,999	1.36%	▲365,670	+41.49%	$48.53Mn
11	Jpmorgan Chase & Co	0000019617	1,238,006	1.35%	▲423,666	+52.03%	$46.43Mn
12	AMERICAN CENTURY COMPANIES INC	0000748054	1,221,485	1.33%	▼226,808	-15.66%	$47.54Mn
13	Morgan Stanley	0000895421	1,146,956	1.25%	▲926,077	+419.27%	$44.64Mn
14	Allspring Global Investments Holdings, LLC	0001890906	1,112,261	1.21%	▲180,208	+19.33%	$43.79Mn
15	North Reef Capital Management LP	0001867831	1,014,274	1.10%	▼250,726	-19.82%	$39.48Mn
16	Ghisallo Capital Management LLC	0001825214	1,000,000	1.09%	▲442,500	+79.37%	$38.92Mn
17	Bank Of America Corp /De/	0000070858	900,882	0.98%	▲597,021	+196.48%	$35.06Mn
18	TWO SIGMA INVESTMENTS, LP	0001179392	893,718	0.97%	▲753,387	+536.86%	$34.78Mn
19	LORD, ABBETT & CO. LLC	0000728100	860,687	0.94%	▲201,018	+30.47%	$33.50K
20	GEODE CAPITAL MANAGEMENT, LLC	0001214717	779,782	0.85%	▲266,985	+52.06%	$30.36Mn

Showing 1 to 20 of 199 holders