XT
MBX

XTX Topco’s MBX Biosciences MBX Stock Holding History

XTX Topco’s Portfolio MBX Stock Details MBX Fund Activity
Bought
Maintained
Sold
Quarter Market Value Status Shares Change in
Stake 		Trade Value Portfolio Weight Portfolio Position
2026
Q1 		$1.59M Buy
53,210
+33,071
+164% +$1.12M 0.03% 1029
2025
Q4 		$635K Sell
20,139
-18,239
-48% -$443K 0.02% 1392
2025
Q3 		$672K Buy
38,378
+26,517
+224% +$355K 0.03% 861
2025
Q2 		$135K Buy
+11,861
New +$121K 0.01% 1813

Other funds holding MBX

FLSM
Frazier Life Sciences Management Palo Alto, California $3.89B AUM 201.1% 1-Year Est. Return
O
OrbiMed New York $5.05B AUM 125.28% 1-Year Est. Return
NMC
NEA Management Company Timonium, Maryland $1.76B AUM 223.33% 1-Year Est. Return
Wellington Management Group
Wellington Management Group Boston, Massachusetts $535B AUM 26.23% 1-Year Est. Return
BlackRock
BlackRock New York $5.72T AUM 30.48% 1-Year Est. Return
Fidelity Investments
Fidelity Investments Boston, Massachusetts $1.9T AUM 41.92% 1-Year Est. Return
DTC
Deep Track Capital Greenwich, Connecticut $6.12B AUM 144% 1-Year Est. Return
NA
NVP Associates Menlo Park, California $176M AUM 208.78% 1-Year Est. Return
PCH
Polar Capital Holdings London, United Kingdom $28.2B AUM 115.26% 1-Year Est. Return
B
Braidwell Stamford, Connecticut $3B AUM 46.72% 1-Year Est. Return

XTX Topco's MBX Position: Q1 2026 in Review

XTX Topco increased its MBX Biosciences (MBX) stake by 164% in Q1 2026, buying an estimated $1.12M and bringing the position to 53,210 shares worth $1.59M. The position accounts for 0.03% of the portfolio, ranked #1029.

XTX Topco first reported a position in MBX in Q2 2025 and has held it in 4 quarters since. 157 funds tracked by Wall St. Rank hold MBX as of Q1 2026.

  • XTX Topco held 53,210 shares of MBX Biosciences worth $1.59M as of Q1 2026.
  • XTX Topco bought 33,071 MBX Biosciences shares in Q1 2026, an estimated $1.12M.
  • MBX Biosciences made up 0.03% of XTX Topco's portfolio in Q1 2026, its #1029 holding.
  • XTX Topco first reported a position in MBX Biosciences in Q2 2025 and has held it in 4 quarters since.
  • 157 funds tracked by Wall St. Rank held MBX Biosciences as of Q1 2026.

Based on XTX Topco's 13F filing for Q1 2026, filed 15 May 2026.