Simplex Trading
MIAX icon

Simplex Trading’s Miami International Holdings MIAX Stock Holding History

Simplex Trading’s Portfolio MIAX Stock Details MIAX Fund Activity
Bought
Maintained
Sold
Quarter Market Value Status Shares Change in
Stake 		Trade Value Portfolio Weight Portfolio Position
2026
Q3 		$131K Sell
3,900
-33,700
-90% -$1.41M ﹤0.01% 5116
2026
Q2 		$1.4M Sell
37,600
-6,200
-14% -$277K ﹤0.01% 2404
2026
Q1 		$1.7M Buy
43,800
+38,800
+776% +$1.6M ﹤0.01% 1967
2025
Q4 		$222K Sell
5,000
-31,500
-86% -$1.4M ﹤0.01% 4128
2025
Q3 		$1.47M Buy
+36,500
New +$1.34M ﹤0.01% 2640

Other funds holding MIAX

Horizon Kinetics Asset Management
Horizon Kinetics Asset Management New York $7.94B AUM 17.78% 1-Year Est. Return
Vanguard Capital Management
Vanguard Capital Management Malvern, Pennsylvania $4.76T AUM
Vanguard Portfolio Management
Vanguard Portfolio Management Malvern, Pennsylvania $2.21T AUM
Invesco
Invesco Atlanta, Georgia $1.27T AUM 50.62% 1-Year Est. Return
American Century Companies
American Century Companies Kansas City, Missouri $229B AUM 33.35% 1-Year Est. Return
Geode Capital Management
Geode Capital Management Boston, Massachusetts $1.92T AUM 36.1% 1-Year Est. Return
State Street
State Street Boston, Massachusetts $3.44T AUM 36.12% 1-Year Est. Return
William Blair & Company
William Blair & Company Chicago, Illinois $38.6B AUM 22.09% 1-Year Est. Return
JP Morgan Chase
JP Morgan Chase New York $1.84T AUM 33.86% 1-Year Est. Return
Franklin Resources
Franklin Resources San Mateo, California $474B AUM 32.39% 1-Year Est. Return

Simplex Trading's MIAX Position: Q3 2026 in Review

Simplex Trading reduced its Miami International Holdings (MIAX) stake by 64% in Q3 2026, selling an estimated $702K and leaving 9,466 shares worth $317K. The position accounts for ﹤0.01% of the portfolio, ranked #4101.

Simplex Trading first reported a position in MIAX in Q4 2025 and has held it in 4 quarters since. The position peaked at $976K in Q2 2026. 138 funds tracked by Wall St. Rank hold MIAX as of Q3 2026.

  • Simplex Trading held 9,466 shares of Miami International Holdings worth $317K as of Q3 2026.
  • Simplex Trading sold 16,788 Miami International Holdings shares in Q3 2026, an estimated $702K.
  • Miami International Holdings made up ﹤0.01% of Simplex Trading's portfolio in Q3 2026, its #4101 holding.
  • Simplex Trading first reported a position in Miami International Holdings in Q4 2025 and has held it in 4 quarters since.
  • Simplex Trading's Miami International Holdings position peaked at $976K in Q2 2026.
  • 138 funds tracked by Wall St. Rank held Miami International Holdings as of Q3 2026.

Based on Simplex Trading's 13F filing for Q3 2026, filed 4 Nov 2026.