Jane Street
MBX

Jane Street’s MBX Biosciences MBX Stock Holding History

Jane Street’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 		– Sell
-86,581
Closed -$2.94M – 13307
2025
Q4 		$2.73M Buy
+86,581
New +$2.1M ﹤0.01% 4214
2024
Q4 		– Sell
-26,570
Closed -$690K – 10857
2024
Q3 		$690K Buy
+26,570
New +$608K ﹤0.01% 6616

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

Jane Street's MBX Position: Q1 2026 in Review

Jane Street sold out of MBX Biosciences (MBX) in Q1 2026, closing a stake of 86,581 shares — an estimated $2.94M sold.

Jane Street first reported a position in MBX in Q3 2024 and held it in 2 quarters. The position peaked at $2.73M in Q4 2025. 157 funds tracked by Wall St. Rank hold MBX as of Q1 2026.

  • Jane Street reported no remaining MBX Biosciences position as of Q1 2026 after selling out during the quarter.
  • Jane Street sold 86,581 MBX Biosciences shares in Q1 2026, an estimated $2.94M.
  • Jane Street first reported a position in MBX Biosciences in Q3 2024 and held it in 2 quarters.
  • Jane Street's MBX Biosciences position peaked at $2.73M in Q4 2025.
  • 157 funds tracked by Wall St. Rank held MBX Biosciences as of Q1 2026.

Based on Jane Street's 13F filing for Q1 2026, filed 12 May 2026.