Simplex Trading
MIAX

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
Q2 		$175K Buy
4,700
+2,100
+81% +$93.9K ﹤0.01% 4883
2026
Q1 		$101K Buy
2,600
+2,200
+550% +$90.6K ﹤0.01% 5072
2025
Q4 		$17.8K Sell
400
-41,700
-99% -$1.86M ﹤0.01% 6584
2025
Q3 		$1.69M Buy
+42,100
New +$1.54M ﹤0.01% 2486

Other funds holding MIAX

HKAM
Horizon Kinetics Asset Management New York $8.82B AUM 23.05% 1-Year Est. Return
BlackRock
BlackRock New York $6.73T AUM 46.02% 1-Year Est. Return
T. Rowe Price Investment Management
T. Rowe Price Investment Management Baltimore, Maryland $153B AUM 38.14% 1-Year Est. Return
Vanguard Portfolio Management
Vanguard Portfolio Management Malvern, Pennsylvania $2.22T AUM
Susquehanna International Group
Susquehanna International Group Bala Cynwyd, Pennsylvania $1.28T AUM 58.89% 1-Year Est. Return
Vanguard Capital Management
Vanguard Capital Management Malvern, Pennsylvania $4.68T AUM
Invesco
Invesco Atlanta, Georgia $1.26T AUM 61.52% 1-Year Est. Return
JD6
J Digital 6 Chicago, Illinois $169M AUM 111.5% 1-Year Est. Return
William Blair & Company
William Blair & Company Chicago, Illinois $38.4B AUM 25.71% 1-Year Est. Return
Balyasny Asset Management
Balyasny Asset Management Chicago, Illinois $80.2B AUM 51.53% 1-Year Est. Return

Simplex Trading's MIAX Position: Q2 2026 in Review

Simplex Trading increased its Miami International Holdings (MIAX) stake by 4.9% in Q2 2026, buying an estimated $55.4K and bringing the position to 26,254 shares worth $976K. The position accounts for ﹤0.01% of the portfolio, ranked #2804.

Simplex Trading first reported a position in MIAX in Q4 2025 and has held it in 3 quarters since. 206 funds tracked by Wall St. Rank hold MIAX as of Q2 2026.

  • Simplex Trading held 26,254 shares of Miami International Holdings worth $976K as of Q2 2026.
  • Simplex Trading bought 1,238 Miami International Holdings shares in Q2 2026, an estimated $55.4K.
  • Miami International Holdings made up ﹤0.01% of Simplex Trading's portfolio in Q2 2026, its #2804 holding.
  • Simplex Trading first reported a position in Miami International Holdings in Q4 2025 and has held it in 3 quarters since.
  • 206 funds tracked by Wall St. Rank held Miami International Holdings as of Q2 2026.

Based on Simplex Trading's 13F filing for Q2 2026, filed 12 Aug 2026.