Janus Henderson Group’s NewAmsterdam Pharma NAMS Stock Holding History

Janus Henderson Group’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
2026 Q1	$72.3M	Sell	2,258,984 -82,739	-4%	-$2.7M	0.03%	340
2025 Q4	$82.3M	Buy	2,341,723 +224,648	+11%	+$8.18M	0.04%	322
2025 Q3	$60.1M	Buy	2,117,075 +155,015	+8%	+$3.72M	0.03%	371
2025 Q2	$35.6M	Sell	1,962,060 -237,573	-11%	-$4.33M	0.02%	452
2025 Q1	$47.9M	Buy	2,199,633 +462,856	+27%	+$10.3M	0.03%	383
2024 Q4	$44.7M	Buy	1,736,777 +196,048	+13%	+$4.16M	0.02%	404
2024 Q3	$25.6M	Buy	1,540,729 +520,772	+51%	+$9.01M	0.01%	525
2024 Q2	$19.6M	Buy	1,019,957 +383,726	+60%	+$7.7M	0.01%	571
2024 Q1	$15M	Buy	+636,231	New	+$12.9M	0.01%	612
2023 Q4	–	Sell	-434,912	Closed	-$3.97M	–	2587
2023 Q3	$3.97M	Buy	+434,912	New	+$4.71M	﹤0.01%	887
2023 Q1	–	Sell	-563,119	Closed	-$5.33M	–	2708
2022 Q4	$5.33M	Buy	+563,119	New	+$5.6M	﹤0.01%	847

Other funds holding NAMS

FLSM

Frazier Life Sciences Management Palo Alto, California $4.59B AUM 237.58% 1-Year Est. Return

Capital World Investors Los Angeles, California $846B AUM 46.74% 1-Year Est. Return

RCM

RA Capital Management Boston, Massachusetts $11.5B AUM 168.77% 1-Year Est. Return

FIS

FCPM III Services Naarden, Netherlands $750M AUM 127.27% 1-Year Est. Return

Fidelity Investments Boston, Massachusetts $2.3T AUM 54.33% 1-Year Est. Return

BCLSI

Bain Capital Life Sciences Investors Boston, Massachusetts $1.68B AUM 126.09% 1-Year Est. Return

Wellington Management Group Boston, Massachusetts $580B AUM 38.23% 1-Year Est. Return

Deerfield Management New York $9.59B AUM 113.36% 1-Year Est. Return

Viking Global Investors Stamford, Connecticut $35.1B AUM 21.36% 1-Year Est. Return

DFO

Duquesne Family Office New York $5.21B AUM 87.01% 1-Year Est. Return

Janus Henderson Group's NAMS Position: Q1 2026 in Review

Janus Henderson Group reduced its NewAmsterdam Pharma (NAMS) stake by 3.5% in Q1 2026, selling an estimated $2.7M and leaving 2,258,984 shares worth $72.3M. The position accounts for 0.03% of the portfolio, ranked #340.

Janus Henderson Group first reported a position in NAMS in Q4 2022 and has held it in 11 quarters since. The position peaked at $82.3M in Q4 2025. 171 funds tracked by Wall St. Rank hold NAMS as of Q1 2026.

Janus Henderson Group held 2,258,984 shares of NewAmsterdam Pharma worth $72.3M as of Q1 2026.
Janus Henderson Group sold 82,739 NewAmsterdam Pharma shares in Q1 2026, an estimated $2.7M.
NewAmsterdam Pharma made up 0.03% of Janus Henderson Group's portfolio in Q1 2026, its #340 holding.
Janus Henderson Group first reported a position in NewAmsterdam Pharma in Q4 2022 and has held it in 11 quarters since.
Janus Henderson Group's NewAmsterdam Pharma position peaked at $82.3M in Q4 2025.
171 funds tracked by Wall St. Rank held NewAmsterdam Pharma as of Q1 2026.

Based on Janus Henderson Group's 13F filing for Q1 2026, filed 15 May 2026.