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Fund detail

Viking Global Investors (Halvorsen)

hedge-fund, active

Quarters 52
2026-03-31 $35.75B
Positions 77
Showing 10 of 10 rows (filtered from 96)

Price is the latest implied close from the selected quarter's 13F (value ÷ shares). Est. Cost is a running average that assumes each quarter's trades cleared near the midpoint of consecutive 13F closes (or yfinance VWAP when available). Most accurate for slow accumulators, least accurate for activists who build positions in a few days.

# Issuer Value ↓ Weight Shares Share Δ Share Δ % Prev Weight First Held Price Est. Cost Unrealized % Status
1 ADAPTIVE BIOTECHNOLOGIES COR ADPT $416.3M 1.16% 29,993,708 +0 +0.00% 1.29% 2019-06-30 $14 ~$48 -71.26%
2 NEWAMSTERDAM PHARMA COMPANY $134.6M 0.38% 4,203,567 +0 +0.00% 0.39% 2022-12-31 $32 ~$11 +184.38%
3 ORUKA THERAPEUTICS INC ORKA $130.8M 0.37% 2,666,690 +0 +0.00% 0.21% 2025-09-30 $49 ~$19 +155.07%
4 SIONNA THERAPEUTICS INC SION $128.1M 0.36% 3,195,181 +0 +0.00% 0.35% 2025-03-31 $40 ~$11 +273.93%
5 PHARVARIS N V $103.2M 0.29% 3,653,310 +0 +0.00% 0.27% 2021-03-31 $28 ~$24 +19.59%
6 INHIBRX BIOSCIENCES INC INBX $96.7M 0.27% 1,437,705 +0 +0.00% 0.30% 2024-06-30 $67 ~$14 +374.45%
7 STANDARD BIOTOOLS INC LAB $53.9M 0.15% 58,651,170 +0 +0.00% 0.20% 2024-03-31 $1 ~$3 -66.08%
8 TREVI THERAPEUTICS INC TRVI $38.2M 0.11% 3,198,644 +0 +0.00% 0.11% 2022-09-30 $12 ~$6 +114.02%
9 GINKGO BIOWORKS HOLDINGS INC DNA $21.9M 0.06% 3,577,128 +0 +0.00% 0.08% 2024-09-30 $6 ~$8 -24.79%
10 PEPGEN INC PEPG $6.2M 0.02% 3,482,434 +0 +0.00% 0.06% 2022-06-30 $2 ~$6 -69.86%