Rock Springs Capital Management LP
Position in ACRS — Aclaris Therapeutics, Inc.
CIK 1595725
Baltimore, MD
Position in ACRS
as of Mar 31, 2026
· filed May 15, 2026
Position Value
$16,772,437
+$3,366,677 QoQ
Shares Held
4,472,650
+0.4% QoQ
Ownership
3.20%
of shares outstanding
% of Portfolio
0.99%
of 13F equity value
Holder Rank
—
not a current holder
Holding Since
Mar 2020
25 quarters on record
Voting authority
Sole 100.ToString("F0")%
Shared 0.ToString("F0")%
None 0.ToString("F0")%
Common Shares in ACRS Over Time
Shares Held
Position Value (USD)
Position in Biotechnology
Healthcare · as of Mar 31, 2026Rock Springs Capital Management LP holds $1,246,050,197 across 66 Biotechnology names. ACRS ranks #26 (1.3% of the industry book) .
| # | Ticker | Company | Shares | Value (USD) | Open |
|---|---|---|---|---|---|
| 1 | RVMD |
Revolution Medicines, Inc.
|
1,209,465 | $117,620,471 | |
| 2 | MDGL |
Madrigal Pharmaceuticals, Inc.
|
170,999 | $89,512,846 | |
| 3 | MIRM |
Mirum Pharmaceuticals, Inc.
|
811,294 | $74,947,339 | |
| 4 | ARGX |
Argenx SE
|
98,500 | $71,929,625 | |
| 5 | RYTM |
Rhythm Pharmaceuticals, Inc.
|
689,748 | $59,987,383 | |
| 6 | INSM |
INSMED Inc
|
314,300 | $51,394,336 | |
| 7 | ASND |
Ascendis Pharma A/S
|
194,000 | $44,373,620 | |
| 8 | XENE |
Xenon Pharmaceuticals Inc.
|
763,020 | $44,369,613 |
All Filings in ACRS
Export CSV
25 filing rows on record
| Report Date | Value (USD) | Shares | Type | Discretion | Filed | |
|---|---|---|---|---|---|---|
| 2026-03-31 | $16,772,437 | 4,472,650 | Shares | Sole | 2026-05-15 | |
| 2025-12-31 | $13,405,760 | 4,453,741 | Shares | Sole | 2026-02-17 | |
| 2025-09-30 | $8,757,687 | 4,609,309 | Shares | Sole | 2025-11-14 | |
| 2025-06-30 | $6,772,418 | 4,769,309 | Shares | Sole | 2025-08-14 | |
| 2025-03-31 | $7,720,852 | 5,046,309 | Shares | Sole | 2025-05-15 | |
| 2024-12-31 | $15,386,686 | 6,204,309 | Shares | Sole | 2025-02-14 | |
| 2024-09-30 | $3,166,519 | 2,753,495 | Shares | Sole | 2024-11-14 | |
| 2024-06-30 | $3,028,844 | 2,753,495 | Shares | Sole | 2024-08-14 | |
| 2024-03-31 | $3,414,333 | 2,753,495 | Shares | Sole | 2024-05-15 | |
| 2023-12-31 | $3,148,419 | 2,998,495 | Shares | Sole | 2024-02-14 | |
| 2023-09-30 | $27,129,075 | 3,960,449 | Shares | Sole | 2023-11-14 | |
| 2023-06-30 | $41,084,374 | 3,961,849 | Shares | Sole | 2023-08-14 | |
| 2023-03-31 | $32,051,358 | 3,961,849 | Shares | Sole | 2023-05-15 | |
| 2022-12-31 | $62,389,671 | 3,961,249 | Shares | Sole | 2023-02-14 | |
| 2022-09-30 | $62,350,059 | 3,961,249 | Shares | Sole | 2022-11-14 | |
| 2022-06-30 | $54,823,000 | 3,927,149 | Shares | Sole | 2022-08-15 | |
| 2022-03-31 | $66,633,186 | 3,865,034 | Shares | Sole | 2022-05-16 | |
| 2021-12-31 | $56,143,985 | 3,861,347 | Shares | Sole | 2022-02-14 | |
| 2021-09-30 | $68,458,176 | 3,803,232 | Shares | Sole | 2021-11-15 | |
| 2021-06-30 | $66,066,198 | 3,762,312 | Shares | Sole | 2021-08-16 | |
| 2021-03-31 | $89,943,638 | 3,569,192 | Shares | Sole | 2021-05-17 | |
| 2020-12-31 | $17,314,367 | 2,676,100 | Shares | Sole | 2021-02-16 | |
| 2020-09-30 | $5,336,108 | 2,076,307 | Shares | Sole | 2020-11-16 | |
| 2020-06-30 | $2,663,304 | 1,644,015 | Shares | Sole | 2020-08-14 | |
| 2020-03-31 | $1,664,000 | 1,600,000 | Shares | Sole | 2020-05-15 | |
| No filing history on record for this holder in this stock. | ||||||