SL
NAMS icon

Siren LLC’s NewAmsterdam Pharma NAMS Stock Holding History

Siren LLC’s Portfolio NAMS Stock Details NAMS Fund Activity
Bought
Maintained
Sold
Quarter Market Value Status Shares Change in
Stake 		Trade Value Portfolio Weight Portfolio Position
2025
Q4 		– Sell
-765,705
Closed -$21.8M – 123
2025
Q3 		$21.8M Sell
765,705
-428,535
-36% -$10.3M 0.85% 33
2025
Q2 		$21.6M Sell
1,194,240
-717,790
-38% -$13.1M 1.12% 28
2025
Q1 		$39.1M Sell
1,912,030
-183,608
-9% -$4.08M 2.21% 13
2024
Q4 		$53.9M Buy
2,095,638
+1,175,074
+128% +$25M 2.38% 9
2024
Q3 		$15.3M Buy
+920,564
New +$15.9M 0.76% 35

Other funds holding NAMS

FLSM
Frazier Life Sciences Management Palo Alto, California $3.89B AUM 201.1% 1-Year Est. Return
Capital World Investors
Capital World Investors Los Angeles, California $733B AUM 35.63% 1-Year Est. Return
RCM
RA Capital Management Boston, Massachusetts $9.44B AUM 157.3% 1-Year Est. Return
FIS
FCPM III Services Naarden, Netherlands $722M AUM 73.61% 1-Year Est. Return
BCLSI
Bain Capital Life Sciences Investors Boston, Massachusetts $1.11B AUM 171.34% 1-Year Est. Return
Fidelity Investments
Fidelity Investments Boston, Massachusetts $1.9T AUM 41.92% 1-Year Est. Return
Wellington Management Group
Wellington Management Group Boston, Massachusetts $535B AUM 26.23% 1-Year Est. Return
Viking Global Investors
Viking Global Investors Stamford, Connecticut $35.7B AUM 21.3% 1-Year Est. Return
DM
Deerfield Management New York $8.48B AUM 99.04% 1-Year Est. Return
Jennison Associates
Jennison Associates New York $145B AUM 34.61% 1-Year Est. Return

Siren LLC's NAMS Position: Q4 2025 in Review

Siren LLC sold out of NewAmsterdam Pharma (NAMS) in Q4 2025, closing a stake of 765,705 shares — an estimated $21.8M sold.

Siren LLC first reported a position in NAMS in Q3 2024 and held it in 5 quarters. The position peaked at $53.9M in Q4 2024. 186 funds tracked by Wall St. Rank hold NAMS as of Q4 2025.

  • Siren LLC reported no remaining NewAmsterdam Pharma position as of Q4 2025 after selling out during the quarter.
  • Siren LLC sold 765,705 NewAmsterdam Pharma shares in Q4 2025, an estimated $21.8M.
  • Siren LLC first reported a position in NewAmsterdam Pharma in Q3 2024 and held it in 5 quarters.
  • Siren LLC's NewAmsterdam Pharma position peaked at $53.9M in Q4 2024.
  • 186 funds tracked by Wall St. Rank held NewAmsterdam Pharma as of Q4 2025.

Based on Siren LLC's 13F filing for Q4 2025, filed 13 Feb 2026.