Who owns Boston Scientific (BSX)
Which tracked institutional funds hold BSX, how they are positioned, and who is buying versus exiting — from SEC Form 13F-HR filings. See BSX company fundamentals →
Ownership as of the 2026-Q2 13F filings (latest filed 2026-09-22). 13F is disclosed up to 45 days after quarter-end, so the most recent quarter fills in over the following weeks.
How the tape is positioned
The tracked-fund tape on BSX is one-sided between 2026-Q1 and 2026-Q2: 181 added or opened and 823 trimmed or exited — on balance reducing.
A prompt to read the filings, not a verdict. 13F is a quarter-end snapshot disclosed up to 45 days late; a fund adds or exits for mandate, benchmark, and timing reasons that have nothing to do with a view on the stock. This is a starting question, not a signal to trade.
Conviction spread
BSX’s largest tracked holder by dollar value, BlackRock, Inc., sizes it at 0.1% of its own reported 13F book, while the median holder sizes it at 0.1% of theirs — a 0.0pp gap the other way — the median holder sizes BSX more heavily than its largest holder by dollar value does.
Book-share is each fund’s reported value in BSX divided by its whole reported 13F book, so it is comparable across funds of different sizes and is unaffected by stock splits. A higher share means a fund has committed more of its book to the name — a starting question about conviction, not a verdict or a signal to trade.
Institutional & insider positioning
Between 2026-Q1 and 2026-Q2, across 1388 tracked filers holding BSX, 690 increased or opened the position and 1008 reduced or closed it; over the same quarter, open-market insider Form 4s were net purchases. A multi-insider buy cluster also fired inside the quarter.
This fuses two public signals for the same quarter — how tracked institutions changed their positions and whether insiders bought or sold in the open market. It describes what was filed; it is a starting question, not a verdict or a signal to trade.
New buyers & exits
Funds opening or closing a position in BSX between the 2026-Q1 and 2026-Q2 13F filings, and the largest changes among funds holding it in both. New buyers and exits are counted on fund presence (split-invariant); adds and trims are measured on reported value.
New buyers 53
- Jupiter Topco LLC$803M
- DEERFIELD MANAGEMENT COMPANY, L.P.$56M
- LGT CAPITAL PARTNERS LTD.$39M
- JUPITER ASSET MANAGEMENT LTD$37M
- CAUSEWAY CAPITAL MANAGEMENT LLC$31M
- Nykredit A/S$25M
Full exits 186
- Bollard Group LLC$1.2B
- JANUS HENDERSON GROUP PLC$1.0B
- Amundi$886M
- EDGEWOOD MANAGEMENT LLC$479M
- Handelsbanken Fonder AB$162M
- KBC Group NV$152M
Largest adds
- MASSACHUSETTS FINANCIAL SERVICES CO /MA/$781M
- FIL Ltd$325M
- JANE STREET GROUP, LLC$263M
- TWO SIGMA INVESTMENTS, LP$236M
- Capital Research Global Investors$161M
- ARROWSTREET CAPITAL, LIMITED PARTNERSHIP$122M
Largest trims
- FMR LLC$2.7B
- BlackRock, Inc.$2.5B
- VANGUARD CAPITAL MANAGEMENT LLC$1.9B
- STATE STREET CORP$1.3B
- NORGES BANK$1.1B
- JPMORGAN CHASE & CO$1.1B
Institutional holders
One row per tracked fund, most shares held first (every row is from one quarter; reported value breaks ties). “% of value” is the fund’s share of this security’s tracked institutional value — not of shares outstanding.
| Fund | Shares | Reported value | % of value | Quarter |
|---|---|---|---|---|
| BlackRock, Inc. added | 129,680,916 | $5.5B | 11.5% | 2026-Q2 |
| VANGUARD CAPITAL MANAGEMENT LLC added | 97,087,553 | $4.1B | 8.6% | 2026-Q2 |
| STATE STREET CORP added | 70,111,196 | $3.0B | 6.2% | 2026-Q2 |
| PRIMECAP MANAGEMENT CO/CA/ added | 50,520,914 | $2.2B | 4.5% | 2026-Q2 |
| FMR LLC trimmed | 45,702,845 | $2.0B | 4.1% | 2026-Q2 |
| GEODE CAPITAL MANAGEMENT, LLC added | 33,440,102 | $1.4B | 3.0% | 2026-Q2 |
| VANGUARD PORTFOLIO MANAGEMENT LLC trimmed | 29,792,794 | $1.3B | 2.7% | 2026-Q2 |
| D. E. Shaw & Co., Inc. added | 25,457,409 | $1.1B | 2.3% | 2026-Q2 |
| MASSACHUSETTS FINANCIAL SERVICES CO /MA/ added | 24,859,191 | $1.5B | 3.1% | 2026-Q2 |
| JPMORGAN CHASE & CO trimmed | 23,907,838 | $1.0B | 2.2% | 2026-Q2 |
| ARROWSTREET CAPITAL, LIMITED PARTNERSHIP added | 23,293,913 | $994M | 2.1% | 2026-Q2 |
| NORGES BANK added | 21,170,029 | $904M | 1.9% | 2026-Q2 |
| TWO SIGMA INVESTMENTS, LP added | 19,359,023 | $826M | 1.7% | 2026-Q2 |
| MORGAN STANLEY trimmed | 18,947,147 | $809M | 1.7% | 2026-Q2 |
| Jupiter Topco LLC new | 18,822,853 | $803M | 1.7% | 2026-Q2 |
| GOLDMAN SACHS GROUP INC trimmed | 16,954,342 | $724M | 1.5% | 2026-Q2 |
| Capital World Investors added | 16,812,257 | $718M | 1.5% | 2026-Q2 |
| UBS Group AG added | 16,352,420 | $698M | 1.5% | 2026-Q2 |
| WELLINGTON MANAGEMENT GROUP LLP trimmed | 15,301,828 | $653M | 1.4% | 2026-Q2 |
| Capital Research Global Investors added | 14,180,571 | $605M | 1.3% | 2026-Q2 |
| Invesco Ltd. added | 13,800,748 | $589M | 1.2% | 2026-Q2 |
| FRANKLIN RESOURCES INC trimmed | 13,772,323 | $588M | 1.2% | 2026-Q2 |
| UBS AM, a distinct business unit of UBS ASSET MANAGEMENT AMERICAS LLC trimmed | 13,091,481 | $559M | 1.2% | 2026-Q2 |
| BANK OF AMERICA CORP /DE/ trimmed | 13,027,783 | $556M | 1.2% | 2026-Q2 |
| NORTHERN TRUST CORP trimmed | 12,964,638 | $553M | 1.2% | 2026-Q2 |
| FIL Ltd added | 12,332,054 | $526M | 1.1% | 2026-Q2 |
| JANE STREET GROUP, LLC added | 12,087,991 | $516M | 1.1% | 2026-Q2 |
| FARALLON CAPITAL MANAGEMENT, L.L.C. added | 10,521,184 | $449M | 0.9% | 2026-Q2 |
| Legal & General Group Plc trimmed | 10,119,264 | $432M | 0.9% | 2026-Q2 |
| AQR CAPITAL MANAGEMENT LLC added | 9,681,750 | $413M | 0.9% | 2026-Q2 |
| CANADA PENSION PLAN INVESTMENT BOARD added | 9,262,404 | $395M | 0.8% | 2026-Q2 |
| DZ BANK AG Deutsche Zentral Genossenschafts Bank, Frankfurt am Main trimmed | 9,227,707 | $394M | 0.8% | 2026-Q2 |
| CHARLES SCHWAB INVESTMENT MANAGEMENT INC added | 9,223,151 | $394M | 0.8% | 2026-Q2 |
| Qube Research & Technologies Ltd added | 8,943,771 | $382M | 0.8% | 2026-Q2 |
| Nuveen, LLC trimmed | 8,695,119 | $371M | 0.8% | 2026-Q2 |
| VANGUARD FIDUCIARY TRUST CO trimmed | 8,345,428 | $356M | 0.7% | 2026-Q2 |
| ROYAL BANK OF CANADA added | 8,100,653 | $346M | 0.7% | 2026-Q2 |
| Bank of New York Mellon Corp trimmed | 7,943,553 | $339M | 0.7% | 2026-Q2 |
| BNP PARIBAS FINANCIAL MARKETS added | 7,620,469 | $325M | 0.7% | 2026-Q2 |
| PRICE T ROWE ASSOCIATES INC /MD/ trimmed | 7,070,412 | $302M | 0.6% | 2026-Q2 |
| DEUTSCHE BANK AG\ trimmed | 5,957,053 | $254M | 0.5% | 2026-Q2 |
| MAVERICK CAPITAL LTD added | 5,937,553 | $253M | 0.5% | 2026-Q2 |
| Ensign Peak Advisors, Inc added | 5,881,367 | $251M | 0.5% | 2026-Q2 |
| DIMENSIONAL FUND ADVISORS LP trimmed | 5,824,298 | $249M | 0.5% | 2026-Q2 |
| MILLENNIUM MANAGEMENT LLC added | 5,437,567 | $211M | 0.4% | 2026-Q2 |
| BNP PARIBAS ASSET MANAGEMENT Holding S.A. trimmed | 5,380,866 | $230M | 0.5% | 2026-Q2 |
| LAZARD ASSET MANAGEMENT LLC added | 5,343,777 | $228M | 0.5% | 2026-Q2 |
| AMERIPRISE FINANCIAL INC trimmed | 5,134,220 | $219M | 0.5% | 2026-Q2 |
| Clearbridge Investments, LLC added | 5,130,774 | $219M | 0.5% | 2026-Q2 |
| CITADEL ADVISORS LLC added | 4,987,748 | $213M | 0.4% | 2026-Q2 |
| Vontobel Holding Ltd. trimmed | 4,871,518 | $208M | 0.4% | 2026-Q2 |
| SCHRODER INVESTMENT MANAGEMENT GROUP trimmed | 4,708,211 | $201M | 0.4% | 2026-Q2 |
| BARCLAYS PLC trimmed | 4,584,260 | $196M | 0.4% | 2026-Q2 |
| 1832 Asset Management L.P. trimmed | 4,556,876 | $194M | 0.4% | 2026-Q2 |
| Swiss National Bank trimmed | 4,191,800 | $179M | 0.4% | 2026-Q2 |
| Assenagon Asset Management S.A. trimmed | 4,173,559 | $178M | 0.4% | 2026-Q2 |
| National Pension Service added | 3,959,598 | $169M | 0.4% | 2026-Q2 |
| Mitsubishi UFJ Asset Management Co., Ltd. added | 3,617,472 | $154M | 0.3% | 2026-Q2 |
| HSBC HOLDINGS PLC added | 3,533,722 | $151M | 0.3% | 2026-Q2 |
| Ninety One UK Ltd trimmed | 3,501,985 | $149M | 0.3% | 2026-Q2 |
| Sumitomo Mitsui Trust Group, Inc. added | 3,427,875 | $146M | 0.3% | 2026-Q2 |
| Employees Provident Fund Board added | 3,358,700 | $143M | 0.3% | 2026-Q2 |
| Vanguard Global Advisers, LLC added | 3,337,790 | $142M | 0.3% | 2026-Q2 |
| VOLORIDGE INVESTMENT MANAGEMENT, LLC added | 3,275,326 | $140M | 0.3% | 2026-Q2 |
| Man Group plc trimmed | 3,225,164 | $138M | 0.3% | 2026-Q2 |
| Caisse de depot et placement du Quebec added | 3,120,394 | $133M | 0.3% | 2026-Q2 |
| Alecta Tjanstepension Omsesidigt added | 3,117,000 | $133M | 0.3% | 2026-Q2 |
| Mirova US LLC added | 3,101,478 | $132M | 0.3% | 2026-Q2 |
| Aberdeen Group plc added | 3,066,626 | $131M | 0.3% | 2026-Q2 |
| WELLS FARGO & COMPANY/MN added | 3,051,613 | $130M | 0.3% | 2026-Q2 |
| Russell Investments Group, Ltd. added | 2,895,696 | $124M | 0.3% | 2026-Q2 |
| VANGUARD ASSET MANAGEMENT, Ltd added | 2,873,191 | $123M | 0.3% | 2026-Q2 |
| Public Sector Pension Investment Board added | 2,804,896 | $120M | 0.2% | 2026-Q2 |
| MANUFACTURERS LIFE INSURANCE COMPANY, THE added | 2,702,583 | $115M | 0.2% | 2026-Q2 |
| RHUMBLINE ADVISERS trimmed | 2,641,843 | $113M | 0.2% | 2026-Q2 |
| NORDEA INVESTMENT MANAGEMENT AB added | 2,610,440 | $111M | 0.2% | 2026-Q2 |
| CITIGROUP INC added | 2,582,561 | $110M | 0.2% | 2026-Q2 |
| Rathbones Group PLC trimmed | 2,539,901 | $108M | 0.2% | 2026-Q2 |
| MARSHALL WACE, LLP trimmed | 2,414,223 | $103M | 0.2% | 2026-Q2 |
| RENAISSANCE TECHNOLOGIES LLC trimmed | 2,412,005 | $103M | 0.2% | 2026-Q2 |
| Allianz Asset Management GmbH added | 2,400,485 | $149M | 0.3% | 2026-Q2 |
| Temasek Holdings (Private) Ltd | 2,399,426 | $102M | 0.2% | 2026-Q2 |
| Pictet Asset Management Holding SA trimmed | 2,393,080 | $102M | 0.2% | 2026-Q2 |
| Unisphere Establishment trimmed | 2,387,800 | $102M | 0.2% | 2026-Q2 |
| CALIFORNIA STATE TEACHERS RETIREMENT SYSTEM trimmed | 2,270,596 | $97M | 0.2% | 2026-Q2 |
| MILFORD FUNDS LTD trimmed | 2,169,484 | $93M | 0.2% | 2026-Q2 |
| NEUBERGER BERMAN GROUP LLC trimmed | 2,126,406 | $91M | 0.2% | 2026-Q2 |
| California Public Employees Retirement System trimmed | 2,047,848 | $87M | 0.2% | 2026-Q2 |
| Phoenix Financial Ltd. added | 1,962,730 | $84M | 0.2% | 2026-Q2 |
| RAYMOND JAMES FINANCIAL INC trimmed | 1,923,305 | $82M | 0.2% | 2026-Q2 |
| STIFEL FINANCIAL CORP trimmed | 1,760,990 | $75M | 0.2% | 2026-Q2 |
| NEW YORK STATE COMMON RETIREMENT FUND trimmed | 1,731,953 | $74M | 0.2% | 2026-Q2 |
| FIRST MANHATTAN CO. LLC. trimmed | 1,697,334 | $72M | 0.2% | 2026-Q2 |
| PRINCIPAL FINANCIAL GROUP INC trimmed | 1,675,210 | $71M | 0.1% | 2026-Q2 |
| ADAGE CAPITAL PARTNERS GP, L.L.C. trimmed | 1,670,022 | $71M | 0.1% | 2026-Q2 |
| SUSQUEHANNA INTERNATIONAL GROUP, LLP added | 1,661,950 | $71M | 0.1% | 2026-Q2 |
| CREDIT AGRICOLE S A trimmed | 1,647,566 | $70M | 0.1% | 2026-Q2 |
| Squarepoint Ops LLC added | 1,624,929 | $69M | 0.1% | 2026-Q2 |
| ALLIANCEBERNSTEIN L.P. trimmed | 1,455,619 | $91M | 0.2% | 2026-Q2 |
| Banque Transatlantique SA added | 914,874 | $71M | 0.1% | 2026-Q2 |
Ownership over time
Tracked institutional holder count and total shares held by filing quarter (independent scales). The curated-era tail and any mid-ingest latest quarter are handled honestly — a partial quarter is not drawn as a collapse.
Reading this table
Funds hold the same stock for different reasons — an index fund “holds” almost everything, an active manager sizes a name to a mandate and a benchmark, and each fund entered at its own price and time. Because 13F is filed up to 45 days after quarter-end, every row is a backward-looking snapshot; a manager may have traded since. Share-class siblings (a company’s A and C shares) are rolled up to one line so a dual-class name is never double-counted. Compare like-for-like. A large holder is not an endorsement, and a fund exiting is not a warning — this is a starting question, not a verdict.
About 13F filings
A Form 13F is a quarterly disclosure that institutional investment managers with over $100 million in US-listed equities must file with the SEC. In plain English: it is a snapshot of the long stock positions a fund held at the end of a quarter. It covers long US-listed equities only — not short positions, options, cash, or private holdings — and the funds shown are the large sample we track, not the complete 13F universe.