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Equibles

RTW INVESTMENTS, LP

Position in RARE — Ultragenyx Pharmaceutical Inc.

CIK 1493215 NEW YORK, NY
Back to RARE Full portfolio

Position in RARE

as of Jun 30, 2026 · filed Aug 14, 2026
Position Value
$260,338,324
+$183,896,069 QoQ
Shares Held
7,796,895
+113.7% QoQ
Ownership
7.91%
of shares outstanding
% of Portfolio
2.22%
of 13F equity value
Holder Rank
#2
of 311 holders
Holding Since
Dec 2021
19 quarters on record
Voting authority Sole 100% Shared 0% None 0%

Common Shares in RARE Over Time

Shares Held

Position Value (USD)

Position in Biotechnology

Healthcare · as of Jun 30, 2026

RTW INVESTMENTS, LP holds $9,530,420,260 across 63 Biotechnology names. RARE ranks #12 (2.7% of the industry book) .

# Ticker Company Shares Value (USD) Open
1 MDGL
Madrigal Pharmaceuticals, Inc.
 1,993,687 $1,070,510,234
2 ARGX
Argenx SE
 709,446 $658,202,715
3 PTCT
Ptc Therapeutics, Inc.
 7,746,415 $631,875,071
4 PTGX
Protagonist Therapeutics, Inc
 5,061,175 $620,398,831
5 CGON
CG Oncology, Inc.
 8,514,590 $604,961,619
6 INSM
INSMED Inc
 4,842,880 $516,347,865
7 TNGX
Tango Therapeutics, Inc.
 13,900,620 $434,533,381
8 SYRE
Spyre Therapeutics, Inc.
 4,251,996 $377,492,204

All Filings in RARE

Export CSV
19 filing rows on record
Report Date Value (USD) Shares
2026-06-30 $260,338,324 7,796,895
2026-03-31 $76,442,255 3,648,795
2025-12-31 $69,003,197 3,000,139
2025-09-30 $98,008,641 3,258,266
2025-06-30 $62,081,136 1,707,402
2025-03-31 $61,825,026 1,707,402
2024-12-31 $82,793,844 1,968,002
2024-09-30 $109,322,511 1,968,002
2024-06-30 $133,982,999 3,259,927
2024-03-31 $330,897,399 7,087,115
2023-12-31 $329,340,452 6,887,086
2023-09-30 $192,691,422 5,405,089
2023-06-30 $249,336,755 5,405,089
2023-03-31 $171,266,939 4,270,996
2022-12-31 $183,787,171 3,966,915
2022-09-30 $97,727,434 2,359,996
2022-06-30 $81,930,123 1,373,284
2022-03-31 $99,727,884 1,373,284
2021-12-31 $115,479,451 1,373,284