Ionis Pharmaceuticals
IONS
362 hedge funds and large institutions have $6.67B invested in Ionis Pharmaceuticals in 2025 Q2 according to their latest regulatory filings, with 80 funds opening new positions, 121 increasing their positions, 109 reducing their positions, and 59 closing their positions.
117% more call options, than puts
Call options by funds: $65.2M | Put options by funds: $30M
100% more funds holding in top 10
Funds holding in top 10: 6 → 12 (+6)
36% more first-time investments, than exits
New positions opened: 80 | Existing positions closed: 59
33% more capital invested
Capital invested by funds: $5.03B → $6.67B (+$1.64B)
11% more repeat investments, than reductions
Existing positions increased: 121 | Existing positions reduced: 109
6% more funds holding
Funds holding: 343 → 362 (+19)
1.21% more ownership
Funds ownership: 104.87% → 106.09% (+1.2%)
Top Buyers
| Rank | Fund | Capital Flow |
|---|---|---|
| 1 |
Adage Capital Partners
Boston,
Massachusetts
|
+$89.2M |
| 2 |
Millennium Management
New York
|
+$65.9M |
| 3 |
PCH
Polar Capital Holdings
London,
United Kingdom
|
+$32.7M |
| 4 |
Balyasny Asset Management
Chicago,
Illinois
|
+$25.2M |
| 5 |
WP
Woodline Partners
San Francisco,
California
|
+$24M |
Top Sellers
| Rank | Fund | Capital Flow |
|---|---|---|
| 1 |
O
OrbiMed
New York
|
-$76.6M |
| 2 |
Wellington Management Group
Boston,
Massachusetts
|
-$67.8M |
| 3 |
Citadel Advisors
Miami,
Florida
|
-$65M |
| 4 |
CCM
Camber Capital Management
Boston,
Massachusetts
|
-$21.9M |
| 5 |
Invesco
Atlanta,
Georgia
|
-$20.2M |
IONS Hedge Fund Activity: Q2 2025 in Review
362 of the 7,595 institutional investors tracked by Wall St. Rank reported a position in Ionis Pharmaceuticals (IONS) for Q2 2025, worth a combined $6.67B — up 33% from $5.03B a quarter earlier.
Buyers outnumbered sellers: 80 funds opened new IONS positions and 59 closed out — a net gain of 21 holders — while 121 added to existing stakes and 109 trimmed.
The largest buyer was Adage Capital Partners, adding an estimated $89.2M. The largest seller was OrbiMed, exiting entirely with an estimated $76.6M sold.
- 362 institutional investors held Ionis Pharmaceuticals (IONS) as of Q2 2025, up from 343 in Q1 2025.
- Funds reported $6.67B of Ionis Pharmaceuticals stock for Q2 2025, up 33% quarter-over-quarter.
- 80 funds opened new Ionis Pharmaceuticals positions in Q2 2025 and 59 closed out, a net change of +21 holders.
- The largest Ionis Pharmaceuticals buyer in Q2 2025 was Adage Capital Partners, an estimated $89.2M added.
- The largest Ionis Pharmaceuticals seller in Q2 2025 was OrbiMed, an estimated $76.6M sold.
Based on aggregated 13F filings for Q2 2025.