Perceptive Advisors ACLX Position
Active6-Fund ConvergencePerceptive Advisors trimmed their position in Arcellx Inc. (ACLX) in Q4 2025, holding $95.6M worth of shares across 1,466,071 shares.
The position was first reported in Q1 2023 and has been tracked across 12 quarterly 13F filings.
ACLX is a convergence signal: 6 specialist biotech funds hold this stock, suggesting high institutional conviction.
There is an upcoming Phase 2 readout for anitocabtagene-autoleucel in 259 days (Dec 31, 2026), making the timing of Perceptive's position particularly relevant.
Short interest stands at 10.9% of float with 1.0 days to cover, indicating significant bearish positioning against Perceptive's long thesis.
About Arcellx Inc.
Arcellx, Inc., a clinical-stage biotechnology company, engages in the development of various immunotherapies for patients with cancer and other incurable diseases. The company's lead ddCAR product candidate is CART-ddBCMA, which is in phase 1 clinical trial for the treatment of patients with relapsed or refractory (r/r) multiple myeloma (MM). It is also developing ACLX-001, an immunotherapeutic combination composed of ARC-T cells and bi-valent SparX proteins targeting BCMA to treat r/r MM; ACLX-002 and ACLX-003 for treating r/r acute myeloid leukemia (AML) and myelodysplastic syndrome (MDS); and other AML/MDS product candidates, as well as solid tumor programs. The company was formerly known as Encarta Therapeutics, Inc. and changed its name to Arcellx, Inc. in January 2016. Arcellx, Inc. was incorporated in 2014 and is headquartered in Gaithersburg, Maryland.
Full company profile →Short Interest
10.9%
1.0 days to cover
Perceptive Advisors ACLX Position History
| Quarter | Action | Shares | Change | Value |
|---|---|---|---|---|
| Q4 2025 | Decreased | 1,466,071 | -1,002,282 | $95.6M |
| Q3 2025 | Decreased | 2,468,353 | -9,647 | $202.7M |
| Q2 2025 | Decreased | 2,478,000 | -448,478 | $163.2M |
| Q1 2025 | Decreased | 2,926,478 | -552,410 | $192.0M |
| Q4 2024 | Decreased | 3,478,888 | -409,781 | $266.8M |
| Q3 2024 | Decreased | 3,888,669 | -1,070 | $324.7M |
| Q2 2024 | Decreased | 3,889,739 | -43,817 | $214.7M |
| Q1 2024 | Decreased | 3,933,556 | -611,253 | $273.6M |
| Q4 2023 | Increased | 4,544,809 | +578,831 | $252.2M |
| Q3 2023 | Decreased | 3,965,978 | -50,419 | $142.3M |
| Q2 2023 | Increased | 4,016,397 | +174,658 | $127.0M |
| Q1 2023 | New | 3,841,739 | +3,841,739 | $118.4M |
Frequently Asked Questions
Does Perceptive Advisors own ACLX?
Yes. As of Q4 2025, Perceptive Advisors holds 1,466,071 shares of Arcellx Inc. (ACLX) valued at $95.6M. This data comes from their SEC 13F filing.
How many hedge funds own ACLX?
6 specialist biotech hedge funds currently hold ACLX, including RA Capital Management, Cormorant Asset Management, Deep Track Capital and 2 more. When 3 or more specialist funds hold the same stock, BiotechEdge flags it as a convergence signal.
When did Perceptive Advisors first buy ACLX?
Perceptive Advisors's position in ACLX was first reported in Q1 2023. 13F filings are reported with a 45-day delay, so the actual purchase may have occurred earlier in the quarter.
Is Perceptive Advisors's ACLX position increasing or decreasing?
Perceptive Advisors trimmed their ACLX position in the most recent quarter, reducing by 1,002,282 shares.
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