Boston Scientific
1,487 hedge funds and large institutions have $57.3B invested in Boston Scientific in 2026 Q2 according to their latest regulatory filings, with 149 funds opening new positions, 589 increasing their positions, 621 reducing their positions, and 326 closing their positions.
139% more call options, than puts
Call options by funds: $2.26B | Put options by funds: $945M
0.81% less ownership
Funds ownership: 90.28% → 89.47% (-0.81%)
5% less repeat investments, than reductions
Existing positions increased: 589 | Existing positions reduced: 621
12% less funds holding
Funds holding: 1,683 → 1,487 (-196)
32% less capital invested
Capital invested by funds: $84.2B → $57.3B (-$27B)
54% less first-time investments, than exits
New positions opened: 149 | Existing positions closed: 326
56% less funds holding in top 10
Funds holding in top 10: 25 → 11 (-14)
Top Buyers
| Rank | Fund | Capital Flow |
|---|---|---|
| 1 |
Primecap Management
Pasadena,
California
|
+$977M |
| 2 |
Massachusetts Financial Services
Boston,
Massachusetts
|
+$753M |
| 3 |
Two Sigma Investments
New York
|
+$540M |
| 4 |
Arrowstreet Capital
Boston,
Massachusetts
|
+$511M |
| 5 |
Fidelity International
Hamilton,
Bermuda
|
+$495M |
Top Sellers
| Rank | Fund | Capital Flow |
|---|---|---|
| 1 |
Fidelity Investments
Boston,
Massachusetts
|
-$1.55B |
| 2 |
Bank of America
Charlotte,
North Carolina
|
-$528M |
| 3 |
JP Morgan Chase
New York
|
-$513M |
| 4 |
Edgewood Management
Greenwich,
Connecticut
|
-$479M |
| 5 |
Parnassus Investments
San Francisco,
California
|
-$371M |
BSX Hedge Fund Activity: Q2 2026 in Review
1,487 of the 8,345 institutional investors tracked by Wall St. Rank reported a position in Boston Scientific (BSX) for Q2 2026, worth a combined $57.3B — down 32% from $84.2B a quarter earlier.
Sellers outnumbered buyers: 326 funds closed out of BSX and 149 opened new positions — a net loss of 177 holders — while 621 trimmed existing stakes and 589 added.
The largest buyer was Primecap Management, adding an estimated $977M. The largest seller was Fidelity Investments, cutting an estimated $1.55B.
- 1,487 institutional investors held Boston Scientific (BSX) as of Q2 2026, down from 1,683 in Q1 2026.
- Funds reported $57.3B of Boston Scientific stock for Q2 2026, down 32% quarter-over-quarter.
- 149 funds opened new Boston Scientific positions in Q2 2026 and 326 closed out, a net change of -177 holders.
- The largest Boston Scientific buyer in Q2 2026 was Primecap Management, an estimated $977M added.
- The largest Boston Scientific seller in Q2 2026 was Fidelity Investments, an estimated $1.55B sold.
Based on aggregated 13F filings for Q2 2026.