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
Q2 		$353K Sell
6,392
-46,818
-88% -$1.64M ﹤0.01% 2763
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 $4.59B AUM 237.58% 1-Year Est. Return
Fidelity Investments
Fidelity Investments Boston, Massachusetts $2.3T AUM 54.33% 1-Year Est. Return
Wellington Management Group
Wellington Management Group Boston, Massachusetts $580B AUM 38.23% 1-Year Est. Return
NMC
NEA Management Company Timonium, Maryland $1.59B AUM 234.06% 1-Year Est. Return
O
OrbiMed New York $5.4B AUM 163.13% 1-Year Est. Return
BlackRock
BlackRock New York $6.73T AUM 46.02% 1-Year Est. Return
PBA
Paradigm Biocapital Advisors New York $5.34B AUM 380.18% 1-Year Est. Return
NA
NVP Associates Menlo Park, California $328M AUM 166.51% 1-Year Est. Return
DTC
Deep Track Capital Greenwich, Connecticut $6.87B AUM 205.24% 1-Year Est. Return
PCH
Polar Capital Holdings London, United Kingdom $42.4B AUM 181.11% 1-Year Est. Return

XTX Topco's MBX Position: Q2 2026 in Review

XTX Topco reduced its MBX Biosciences (MBX) stake by 88% in Q2 2026, selling an estimated $1.64M and leaving 6,392 shares worth $353K. The position accounts for ﹤0.01% of the portfolio, ranked #2763.

XTX Topco first reported a position in MBX in Q2 2025 and has held it in 5 quarters since. The position peaked at $1.59M in Q1 2026. 172 funds tracked by Wall St. Rank hold MBX as of Q2 2026.

  • XTX Topco held 6,392 shares of MBX Biosciences worth $353K as of Q2 2026.
  • XTX Topco sold 46,818 MBX Biosciences shares in Q2 2026, an estimated $1.64M.
  • MBX Biosciences made up ﹤0.01% of XTX Topco's portfolio in Q2 2026, its #2763 holding.
  • XTX Topco first reported a position in MBX Biosciences in Q2 2025 and has held it in 5 quarters since.
  • XTX Topco's MBX Biosciences position peaked at $1.59M in Q1 2026.
  • 172 funds tracked by Wall St. Rank held MBX Biosciences as of Q2 2026.

Based on XTX Topco's 13F filing for Q2 2026, filed 14 Aug 2026.