Rock Springs Capital Management LP ACRS — ACLARIS THERAPEUTICS INC

Ownership history in Rock Springs Capital Management LP  ·  42 quarters on record

AI Ownership Summary

Rock Springs Capital Management LP reported ACLARIS THERAPEUTICS INC (ACRS) in 42 quarterly 13F filings from 2024 Q1 through 2026 Q1. Peak portfolio weight reached 0.99% in 2026 Q1. The latest visible filing shows ACRS at 0.99% of the fund.

This page tracks quarterly shares, estimated market value, portfolio weight, filing dates, and disclosure-aligned stock prices directly from SEC EDGAR 13F filings. Older history is available after unlock; the visible window still shows the most recent pattern.

What this ACRS ownership page tells you

This page is designed to answer the real investor question behind a 13F filing: how meaningful was Rock Springs Capital Management LP's position in ACLARIS THERAPEUTICS INC, and how did that conviction change over time? You can read the holding window, peak weight, latest reported size, disclosure timing, and quarter-by-quarter changes without piecing the story together from raw SEC rows.

Freshest filing
Latest Reported Filing
2026 Q1

ACRS was reported at 0.99% of portfolio in the most recent visible filing.

High-water mark
Peak Conviction
0.99% in 2026 Q1

Peak weight helps separate a token disclosure from a real conviction holding the fund genuinely cared about.

Time in book
Holding Window
2024 Q1 to 2026 Q1

Longer holding windows often tell a very different story from short-lived tactical trades or one-quarter experiments.

Decision context
Why It Matters
Position size beats headlines

Knowing that a fund owned a stock is useful. Knowing whether it was a 0.20% placeholder or a true high-conviction position is where the signal actually starts.

ACRS stock page Rock Springs Capital Management LP fund profile Rock Springs Capital Management LP full holdings
How Rock Springs Capital Management LP held ACRS — position size vs. price
% of Fund (quarterly)    ACRS price (quarter-end, indexed to 100)    SPY (indexed to 100)    QQQ (indexed to 100)
📋 Quarterly Holdings History 9 quarters  ▾
Quarter Action Sold % After 3M Timing Shares Change Chg % % of Fund Mkt Value Filed Price (Filed)
2026 Q1 ADDED — — — 4,472,650 +18,909 +0.4% 0.99% $16.8M 2026-05-15 $4.52
2025 Q4 REDUCED — — — 4,453,741 -155,568 -3.4% 0.69% $13.4M 2026-02-17 $3.26
2025 Q3 REDUCED — — — 4,609,309 -160,000 -3.4% 0.51% $8.8M 2025-11-14 $2.52
2025 Q2 REDUCED 5.5% +35.2% ❌ 4,769,309 -277,000 -5.5% 0.42% $6.8M 2025-08-14 $1.69
2025 Q1 REDUCED 18.7% -7.2% ✅ 5,046,309 -1,158,000 -18.7% 0.44% $7.7M 2025-05-15 $1.22
2024 Q4 ADDED — — — 6,204,309 +3,450,814 +125.3% 0.59% $15.4M 2025-02-14 $2.33
2024 Q3 UNCHANGED — — — 2,753,495 — 0% 0.10% $3.2M 2024-11-14 $2.18
2024 Q2 UNCHANGED — — — 2,753,495 — 0% 0.09% $3.0M 2024-08-14 $1.17
2024 Q1 REDUCED 8.2% -7.3% ✅ 2,753,495 -245,000 -8.2% 0.09% $3.4M 2024-05-15 $1.18
33 older quarters hidden  —  Sign in free or upgrade to Premium to see full history

🏢 Other funds also holding ACRS

As of 2026 Q2 — sorted by position size

Three Bridge Wealth Advisors, LLC 3Y 0.95% CRA Financial Services, LLC 3Y 7Y 0.01% China Universal Asset Management Co., Ltd. 3Y 0.01% Diversified Trust Co 3Y 7Y 0.0% ALPS ADVISORS INC 3Y 7Y 0.0% STRS OHIO 3Y 7Y 0.0% Police & Firemen's Retirement System of New Jersey 0.0% Empirical Financial Services, LLC d.b.a. Empirical Wealth Management 3Y 7Y 0.0% Assenagon Asset Management S.A. 3Y 7Y 0.0% Cambridge Investment Research Advisors, Inc. 3Y 7Y 0.0%

FAQ About Rock Springs Capital Management LP and ACRS

These are the practical questions this page is built to answer before you even open the full history table.

How long has Rock Springs Capital Management LP reported owning ACRS?

Rock Springs Capital Management LP reported ACRS across 9 quarterly 13F filings, from 2024 Q1 through 2026 Q1.

What was the largest reported ACRS position in Rock Springs Capital Management LP's portfolio?

The largest reported portfolio weight for ACRS was 0.99% in 2026 Q1.

What is the latest reported ACRS position on this page?

The most recent filing on this page is 2026 Q1, when Rock Springs Capital Management LP reported 4,472,650 shares, equal to 0.99% of portfolio, with an estimated market value of $16.8M.

What does the chart on this ACRS ownership page compare?

The chart compares Rock Springs Capital Management LP's quarterly ACRS portfolio weight with the stock's indexed share price, so you can see whether the fund was building, trimming, or holding the position as price moved.

How well did Rock Springs Capital Management LP time their ACRS position?

Based on 13F filing dates vs. subsequent ACRS price moves, Rock Springs Capital Management LP correctly timed 14 out of 35 reported position changes (40%). The annualised alpha on ACRS relative to SPY over the holding period was -25.0%.

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