Boston Scientific
BSX
1,708 hedge funds and large institutions have $131B invested in Boston Scientific in 2025 Q3 according to their latest regulatory filings, with 179 funds opening new positions, 767 increasing their positions, 554 reducing their positions, and 132 closing their positions.
38% more repeat investments, than reductions
Existing positions increased: 767 | Existing positions reduced: 554
36% more first-time investments, than exits
New positions opened: 179 | Existing positions closed: 132
14% more call options, than puts
Call options by funds: $1.13B | Put options by funds: $989M
1% more funds holding
Funds holding: 1,687 → 1,708 (+21)
0.86% less ownership
Funds ownership: 91.53% → 90.67% (-0.86%)
7% less funds holding in top 10
Funds holding in top 10: 42 → 39 (-3)
10% less capital invested
Capital invested by funds: $145B → $131B (-$14.2B)
Top Buyers
| Rank | Fund | Capital Flow |
|---|---|---|
| 1 |
Parnassus Investments
San Francisco,
California
|
+$711M |
| 2 |
Polen Capital Management
Boca Raton,
Florida
|
+$580M |
| 3 |
Millennium Management
New York
|
+$403M |
| 4 |
ECU
Egerton Capital (UK)
London,
United Kingdom
|
+$380M |
| 5 |
Citadel Advisors
Miami,
Florida
|
+$363M |
Top Sellers
| Rank | Fund | Capital Flow |
|---|---|---|
| 1 |
Wellington Management Group
Boston,
Massachusetts
|
-$1.86B |
| 2 |
Fidelity Investments
Boston,
Massachusetts
|
-$915M |
| 3 |
VOYA Investment Management
Atlanta,
Georgia
|
-$452M |
| 4 |
Artisan Partners
Milwaukee,
Wisconsin
|
-$390M |
| 5 |
T. Rowe Price Associates
Baltimore,
Maryland
|
-$274M |
BSX Hedge Fund Activity: Q3 2025 in Review
1,708 of the 7,619 institutional investors tracked by Wall St. Rank reported a position in Boston Scientific (BSX) for Q3 2025, worth a combined $131B — down 9.8% from $145B a quarter earlier.
Buyers outnumbered sellers: 179 funds opened new BSX positions and 132 closed out — a net gain of 47 holders — while 767 added to existing stakes and 554 trimmed.
The largest buyer was Parnassus Investments, adding an estimated $711M. The largest seller was Wellington Management Group, cutting an estimated $1.86B.
- 1,708 institutional investors held Boston Scientific (BSX) as of Q3 2025, up from 1,687 in Q2 2025.
- Funds reported $131B of Boston Scientific stock for Q3 2025, down 9.8% quarter-over-quarter.
- 179 funds opened new Boston Scientific positions in Q3 2025 and 132 closed out, a net change of +47 holders.
- The largest Boston Scientific buyer in Q3 2025 was Parnassus Investments, an estimated $711M added.
- The largest Boston Scientific seller in Q3 2025 was Wellington Management Group, an estimated $1.86B sold.
Based on aggregated 13F filings for Q3 2025.