BlackRock
MBX

BlackRock’s MBX Biosciences MBX Stock Holding History

BlackRock’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 		$87.8M Buy
2,941,406
+21,650
+0.7% +$736K ﹤0.01% 2180
2025
Q4 		$92.1M Buy
2,919,756
+962,295
+49% +$23.3M ﹤0.01% 2155
2025
Q3 		$34.3M Buy
1,957,461
+945,915
+94% +$12.6M ﹤0.01% 2749
2025
Q2 		$11.5M Buy
1,011,546
+228,504
+29% +$2.33M ﹤0.01% 3341
2025
Q1 		$5.78M Buy
783,042
+55,090
+8% +$582K ﹤0.01% 3589
2024
Q4 		$13.4M Buy
+727,952
New +$15.5M ﹤0.01% 3267

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
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
VCM
Vanguard Capital Management Malvern, Pennsylvania $4.04T AUM

BlackRock's MBX Position: Q1 2026 in Review

BlackRock increased its MBX Biosciences (MBX) stake by 0.74% in Q1 2026, buying an estimated $736K and bringing the position to 2,941,406 shares worth $87.8M. The position accounts for ﹤0.01% of the portfolio, ranked #2180.

BlackRock first reported a position in MBX in Q4 2024 and has held it in 6 quarters since. The position peaked at $92.1M in Q4 2025. 157 funds tracked by Wall St. Rank hold MBX as of Q1 2026.

  • BlackRock held 2,941,406 shares of MBX Biosciences worth $87.8M as of Q1 2026.
  • BlackRock bought 21,650 MBX Biosciences shares in Q1 2026, an estimated $736K.
  • MBX Biosciences made up ﹤0.01% of BlackRock's portfolio in Q1 2026, its #2180 holding.
  • BlackRock first reported a position in MBX Biosciences in Q4 2024 and has held it in 6 quarters since.
  • BlackRock's MBX Biosciences position peaked at $92.1M in Q4 2025.
  • 157 funds tracked by Wall St. Rank held MBX Biosciences as of Q1 2026.

Based on BlackRock's 13F filing for Q1 2026, filed 13 May 2026.