KALARIS THERAPEUTICS INC (KLRS) Institutional Ownership Changes & 13F Activity
KALARIS THERAPEUTICS INC (KLRS). Institutional ownership data tracks hedge funds, asset managers, and other institutional investors based on recent SEC Form 13F filings (Q4 2025). This page analyzes institutional buying and selling activity, new holdings, and sold-out positions in the latest reporting period. Notable filers include Samsara Biocapital, Llc, Rtw Investments, Lp, Paradigm Biocapital Advisors Lp, Siren, L.L.C., and Alyeska Investment Group, L.P..
| Institution | Type | Change in shares | Change Position % | Shares | Reported stock balance | Portfolio quarter | Filing date |
|---|---|---|---|---|---|---|---|
| Ikarian Capital, Llc | Buy | +360,000 | — | 360,000 | $3.04M | Q4 2025 | Feb 18, 2026 |
| Raymond James Financial Inc | Buy | +88,436 | — | 88,436 | $746.40K | Q4 2025 | Feb 18, 2026 |
| Samsara Biocapital, Llc | Buy | +12,948,081 | — | 12,948,081 | $109.28M | Q4 2025 | Feb 17, 2026 |
| Rtw Investments, Lp | Buy | +1,300,000 | — | 1,300,000 | $10.97M | Q4 2025 | Feb 17, 2026 |
| Paradigm Biocapital Advisors Lp | Buy | +700,000 | — | 700,000 | $5.91M | Q4 2025 | Feb 17, 2026 |
| Adar1 Capital Management, Llc | Buy | +100,000 | — | 100,000 | $844.00K | Q4 2025 | Feb 17, 2026 |
| Woodline Partners Lp | Buy | +100,000 | — | 100,000 | $844.00K | Q4 2025 | Feb 17, 2026 |
| Boothbay Fund Management, Llc | Buy | +92,261 | — | 92,261 | $778.68K | Q4 2025 | Feb 17, 2026 |
| Redmile Group, Llc | Buy | +82,955 | — | 82,955 | $700.14K | Q4 2025 | Feb 17, 2026 |
| 683 Capital Management, Llc | Buy | +80,590 | — | 80,590 | $680.18K | Q4 2025 | Feb 17, 2026 |
| Two Sigma Investments, Lp | Buy | +27,759 | — | 27,759 | $234.29K | Q4 2025 | Feb 17, 2026 |
| Bridgeway Capital Management, Llc | Buy | +22,500 | — | 22,500 | $189.90K | Q4 2025 | Feb 17, 2026 |
| Rbf Capital, Llc | Buy | +17,391 | — | 17,391 | $146.78K | Q4 2025 | Feb 17, 2026 |
| Northern Trust Corp | Buy | +13,654 | — | 13,654 | $115.24K | Q4 2025 | Feb 17, 2026 |
| Susquehanna International Group, Llp | Buy | +12,856 | — | 12,856 | $108.50K | Q4 2025 | Feb 17, 2026 |
| Xtx Topco Ltd | Buy | +10,897 | — | 10,897 | $91.97K | Q4 2025 | Feb 17, 2026 |
| Fmr Llc | Buy | +7,806 | — | 7,806 | $65.88K | Q4 2025 | Feb 17, 2026 |
| Bank Of America Corp | Buy | +6,704 | — | 6,704 | $56.58K | Q4 2025 | Feb 17, 2026 |
| Royal Bank Of Canada | Buy | +113 | — | 113 | $1.00K | Q4 2025 | Feb 17, 2026 |
| Siren, L.L.C. | Buy | +435,798 | — | 435,798 | $3.68M | Q4 2025 | Feb 13, 2026 |
| Alyeska Investment Group, L.P. | Buy | +403,551 | — | 403,551 | $3.40M | Q4 2025 | Feb 13, 2026 |
| Kalehua Capital Management Llc | Buy | +139,901 | — | 139,901 | $1.18M | Q4 2025 | Feb 13, 2026 |
| Marshall Wace, Llp | Buy | +72,876 | — | 72,876 | $615.07K | Q4 2025 | Feb 13, 2026 |
| Omers Administration Corp | Buy | +30,000 | — | 30,000 | $253.20K | Q4 2025 | Feb 13, 2026 |
| Morgan Stanley | Buy | +27,948 | — | 27,948 | $235.88K | Q4 2025 | Feb 13, 2026 |
| State Street Corp | Buy | +25,410 | — | 25,410 | $214.46K | Q4 2025 | Feb 13, 2026 |
| Squarepoint Ops Llc | Buy | +25,367 | — | 25,367 | $214.10K | Q4 2025 | Feb 13, 2026 |
| Walleye Capital Llc | Buy | +11,225 | — | 11,225 | $94.74K | Q4 2025 | Feb 13, 2026 |
| Barclays Plc | Buy | +6,065 | — | 6,065 | $51.19K | Q4 2025 | Feb 13, 2026 |
| Citigroup Inc | Buy | +1 | — | 1 | $8.00 | Q4 2025 | Feb 13, 2026 |
Frequently asked questions about KLRS activity
Which institutional owners are buying KLRS?
Institutional owners buying KLRS include investors who have either initiated new positions or increased their existing holdings based on recent SEC 13F filings. The activity table above highlights which funds added shares in the latest reporting periods and how their positions changed over time.
What does "buy" mean in KLRS activity?
"Buy" means an investor increased their reported position in KLRS compared to the prior reporting period. This reflects growing exposure to KALARIS THERAPEUTICS INC (KLRS) rather than necessarily a brand-new position (though new positions also appear as buys when prior quantity was zero).
Is institutional interest in KLRS increasing?
Institutional interest in KLRS can be assessed by comparing the number of tracked funds adding or increasing positions versus those trimming or exiting across the periods shown. A higher number of additions typically signals increasing participation among large filers, but it should be read alongside position sizes and the full table.
Related KLRS Institutional Insights
- KLRS Overview
- KLRS 13F Institutional Holders
- KLRS Superinvestors
- Healthcare Sector Institutional Ownership
- Healthcare Sector Portfolio Overlap
- Institutional Portfolio Overlap & Shared Holdings
- Most Bought Healthcare Stocks By Institutional Investors
- Most Sold Healthcare Stocks By Institutional Investors
- KLRS Insider Trading & SEC Form 4 Activity
- KLRS Articles
- Top Institutional Investor Stock Rankings