MIAX

Miami International Holdings
FinancialsUSCUSIP 59356Q108◍ Confluence graph
Tracked 13F Holders
190
-99 QoQ
13F Value (tracked)
$1.9B
Insider Net · 180d
-$65.7M
0↑ 10↓
Recent Filings
15
Smart-money sentimentMixed
BearishBullish
13F funds (latest Q)46 adding · 15 trimming
Insider net (180d)-$65.7M

Who owns MIAX?

190 tracked 13F filers

190 tracked 13F filers disclose a position in MIAX as of the latest SEC 13F filings, a combined $1.9B in reported value. Holders and values reflect the 13F filers Arkolith currently tracks, not the entire institutional universe. Counts and totals are a floor, not the full institutional ownership.

All quarters use one ordinary-share-equivalent series. Historical ADS are converted at 2 ADS = 1 ordinary share. Expand a row for the exact calculation; the residual is not classified as a trade.
2 source-reported value rows are withheld because the reported units do not agree with same-security peers. Share counts remain visible and unchanged.
#FundPosition valueSharesLast moveAs ofHistory
1HORIZON KINETICS ASSET MANAGEMENT LLC
$291.4M
7.8M
+127%
Added · +4.4M sh
Q2 2026
2T. Rowe Price Investment Management, Inc.
Withheld
4.1M
+37%
Added · +1.1M sh
Q1 2026
3SUSQUEHANNA INTERNATIONAL GROUP, LLP
$128.3M
3.3M
+0.3%
Added · +11K sh
Q1 2026
4BlackRock, Inc.
$86.9M
2.2M
+27%
Added · +479K sh
Q1 2026
5BLAIR WILLIAM & CO/IL
$65.8M
1.8M
+166%
Added · +1.1M sh
Q2 2026
6CITADEL ADVISORS LLC
$62.6M
1.6M
+159%
Added · +988K sh
Q1 2026
7Alyeska Investment Group, L.P.
$56.3M
1.4M
+13%
Added · +161K sh
Q1 2026
8STATE STREET CORP
$53.2M
1.4M
+101%
Added · +721K sh
Q2 2026
9VANGUARD CAPITAL MANAGEMENT LLC
$55.1M
1.4M
First observed position
No prior filed position
Q1 2026
10GEODE CAPITAL MANAGEMENT, LLC
$51.9M
1.4M
+79%
Added · +616K sh
Q2 2026
11VANGUARD PORTFOLIO MANAGEMENT LLC
$53.5M
1.4M
First observed position
No prior filed position
Q1 2026
12ADAGE CAPITAL PARTNERS GP, L.L.C.
$48.5M
1.2M
+41%
Added · +366K sh
Q1 2026
13JPMORGAN CHASE & CO
$46.4M
1.2M
+52%
Added · +424K sh
Q1 2026
14AMERICAN CENTURY COMPANIES INC
$47.5M
1.2M
−16%
Reduced · −227K sh
Q1 2026
15MORGAN STANLEY
$44.6M
1.1M
+419%
Added · +926K sh
Q1 2026
16North Reef Capital Management LP
$39.5M
1.0M
−20%
Reduced · −251K sh
Q1 2026
17BANK OF AMERICA CORP /DE/
$35.1M
901K
+196%
Added · +597K sh
Q1 2026
18TWO SIGMA INVESTMENTS, LP
$34.8M
894K
+537%
Added · +753K sh
Q1 2026
19Allspring Global Investments Holdings, LLC
$33.5M
858K
−23%
Reduced · −255K sh
Q2 2026
20Walleye Capital LLC
$27.1M
728K
19×
Added · +690K sh
Q2 2026
21WESTFIELD CAPITAL MANAGEMENT CO LP
$26.0M
701K
New
+701K sh
Q2 2026
22NewEdge Advisors, LLC
$25.3M
682K
17×
Added · +643K sh
Q2 2026
23Caldwell Investment Management Ltd.
$22.3M
600K
−9.6%
Reduced · −64K sh
Q2 2026
24BNP PARIBAS FINANCIAL MARKETS
$22.3M
572K
+200%
Added · +381K sh
Q1 2026
25FRANKLIN RESOURCES INC
$22.1M
568K
+33%
Added · +141K sh
Q1 2026

Holders and values reflect the 13F filers Arkolith currently tracks, not the entire institutional universe. Counts and totals are a floor, not the full institutional ownership.

Is MIAX being bought or sold by institutions?

Last quarter, 18 funds opened a new position in MIAX and 28 added to an existing one, while 15 reduced and 0 exited entirely — based on 13F filings from active, signal-eligible managers (passive index funds and other mechanical holders are excluded from this count).

Opened (NEW)
18
funds
Added
28
funds
Reduced
15
funds
Exited
0
funds

Funds that own MIAX also own

CompanyCo-held byCombined value
AMAZON.COM INCAMZN105 funds$138.9B
ALPHABET INC-CL AGOOGL103 funds$110.8B
MICROSOFT CORPMSFT102 funds$192.5B
NVIDIA CORPNVDA101 funds$277.1B
APPLE INCAAPL100 funds$204.6B
META PLATFORMS INC-CLASS AMETA100 funds$76.9B
JPMORGAN CHASE & COJPM98 funds$44.8B
VISA INC-CLASS A SHARESV98 funds$42.2B
BANK OF AMERICA CORPBAC98 funds$21.8B
ALPHABET INC-CL CGOOG96 funds$90.4B
MICRON TECHNOLOGY INCMU96 funds$27.4B
BROADCOM INCAVGO94 funds$112.3B

Ranked by how many of MIAX's institutional holders also hold each name, a cross-fund conviction signal.

Insider activity (Form 4)

Full insider page →
Buys · 180d
$0
0 insiders
Sells · 180d
$65.7M
10 insiders
Net
-$65.7M
57 P/S txns
Signal
Net Selling
open-market
DateInsiderRoleActionSharesValue
Aug 19, 2026Gallagher Thomas P.Chairman & CEO, DirectorSell (S)150K$6.2M
Aug 17, 2026Emmons LanceEVP and CFOSell (S)35K$1.5M
Aug 17, 2026Schwarzkopf CynthiaDirectorSell (S)5K$214K
Aug 4, 2026Deitzel EdwardEVP, CRO, CCO MIAX ExchangesSell (S)11K$504K
Aug 4, 2026Schafer Douglas M. JREVP and CIOSell (S)48K$2.2M
Aug 4, 2026Gallagher Thomas P.Chairman & CEO, DirectorSell (S)48K$2.2M
Aug 4, 2026Comly Barbara J.EVP, GC & Corporate SecretarySell (S)44K$2.0M
Aug 4, 2026Eckert Kurt M.DirectorSell (S)1K$49K
Aug 4, 2026Jayabalan HarishEVP, CISO and CROSell (S)20K$918K
Aug 4, 2026Teekell Judson GrayDirectorSell (S)3K$137K
Jul 15, 2026Schwarzkopf CynthiaDirectorSell (S)5K$210K
Jul 13, 2026Comly Barbara J.EVP, GC & Corporate SecretarySell (S)28K$1.2M

Institutional ownership over time

79 funds-20 since Q3 2025
089178Q3 2025Q4 2025Q1 2026Q2 2026
funds holding aggregate valuelatest $771.5M

Recent filings

15 shown

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Connected entities for MIAX

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Ask your agent what changed in MIAX

This stock page is the public Follow view. For one current, evidence-backed answer, use capital_change_brief through REST or MCP. It compares tracked 13F changes with qualifying Form 4 activity and cites the SEC evidence.

Copy-paste
curl -H "Authorization: Bearer YOUR_API_KEY" \
  "https://arkolith.com/api/v1/stocks/MIAX/capital-change-brief"
Ask your agent
Use Arkolith's capital_change_brief for MIAX.
Tell me what changed, whether insider activity
corroborates it, and cite the SEC evidence.

13F holdings + Form 4 insider transactions + end-of-day price history + the live filing stream, joined for MIAX. Filings are public domain, sourced to SEC EDGAR; price series derived from end-of-day closes.