BOSTON SCIENTIFIC CORP (BSX)
Institutional ownership reported to the SEC as of Q2 2026, across 32 quarters.
Institutions report 1,334,423,712 shares against 1,449,229,526 outstanding. Shares only - option lines are excluded, which is why this can be compared with the company at all. The count comes from the cover page of the company's own most recent report, so it is dated when that was filed rather than at quarter end. A figure this high can overstate: where an adviser and a sub-adviser both report the same shares, both are counted.
Calls and puts are the parts of reported value carried in derivative lines rather than shares, and they point in opposite directions: a manager holding calls is positioned for the security, one holding puts against it - or hedging shares they already own, which is why index funds carry so many. Most sites add the two together and report one figure, which averages away the only interesting part.
Holders
| Filer | Value | Shares | Their book | Held | Change |
|---|---|---|---|---|---|
| BlackRock, Inc. | $5.5B | 129,680,916 | 0.08% | 8q | -1.6%-$91.4M |
| VANGUARD CAPITAL MANAGEMENT LLC | $4.1B | 97,087,553 | 0.09% | 2q | +0.7%+$28.9M |
| STATE STREET CORP | $3.0B | 70,111,196 | 0.09% | 31q | +3.1%+$90.7M |
| PRIMECAP MANAGEMENT CO/CA/ | $2.2B | 50,520,914 | 1.28% | 31q | +55.3%+$767.9M |
| FMR LLC | $2.0B | 45,702,845 | 0.08% | 31q | -38.4%-$1.2B |
| MASSACHUSETTS FINANCIAL SERVICES CO /MA/ | $1.5B | 24,859,191 | 0.48% | 31q | +126.1%+$835.4M |
| JANE STREET GROUP, LLC | $1.4B incl. $925.1M options CALL+PUT | 12,087,991 | 0.12% | 31q | +199.8%+$960.3M |
| GEODE CAPITAL MANAGEMENT, LLC | $1.4B | 33,440,102 | 0.08% | 31q | HELD |
| VANGUARD PORTFOLIO MANAGEMENT LLC | $1.3B | 29,792,794 | 0.06% | 2q | HELD |
| JPMORGAN CHASE & CO | $1.2B incl. $183.7M options CALL+PUT | 23,907,838 | 0.07% | 31q | -28.3%-$483.1M |
| D. E. Shaw & Co., Inc. | $1.2B incl. $77.2M options CALL+PUT | 25,457,409 | 0.55% | 31q | +4.7%+$52.3M |
| ARROWSTREET CAPITAL, LIMITED PARTNERSHIP | $994.2M | 23,293,913 | 0.44% | 21q | +67.7%+$401.3M |
| NORGES BANK | $903.5M | 21,170,029 | 0.09% | 32q | -8.2%-$80.9M |
| TWO SIGMA INVESTMENTS, LP | $828.9M incl. $2.6M options CALL+PUT | 19,359,023 | 0.60% | 31q | +105.7%+$425.9M |
| GOLDMAN SACHS GROUP INC | $819.8M incl. $96.2M options CALL+PUT | 16,954,342 | 0.07% | 31q | -10.3%-$93.7M |
| MORGAN STANLEY | $808.7M | 18,947,147 | 0.04% | 35q | -14.9%-$141.7M |
| Jupiter Topco LLC | $803.4M | 18,822,853 | 0.33% | new | FIRST |
| Bollard Group LLC | $786.2M | 18,420,720 | 23.93% | 31q | -0.6%-$4.8M |
| Capital World Investors | $717.6M | 16,812,257 | 0.08% | 12q | +9.8%+$64.1M |
| UBS Group AG | $711.5M incl. $13.6M options CALL+PUT | 16,352,420 | 0.09% | 31q | +10.3%+$66.5M |
| WELLINGTON MANAGEMENT GROUP LLP | $653.1M | 15,301,828 | 0.11% | 31q | -18.8%-$150.7M |
| 1832 Asset Management L.P. | $642.6M incl. $448.1M options CALL | 4,556,876 | 0.32% | new | NEW |
| Amundi | $610.2M | 14,296,121 | 0.15% | 21q | +1.2%+$7.4M |
| Capital Research Global Investors | $605.3M | 14,180,571 | 0.08% | 10q | +100.3%+$303.0M |
| FRANKLIN RESOURCES INC | $596.7M incl. $8.9M options CALL | 13,772,323 | 0.13% | 30q | -5.0%-$31.5M |
| Invesco Ltd. | $589.0M | 13,800,748 | 0.05% | 31q | +52.5%+$202.7M |
| UBS AM, a distinct business unit of UBS ASSET MANAGEMENT AMERICAS LLC | $558.7M | 13,091,481 | 0.10% | 31q | -3.1%-$18.0M |
| BANK OF AMERICA CORP /DE/ | $556.0M | 13,027,783 | 0.04% | 31q | -42.8%-$415.2M |
| NORTHERN TRUST CORP | $553.3M | 12,964,638 | 0.06% | 31q | -3.1%-$17.5M |
| FIL Ltd | $526.3M | 12,332,054 | 0.38% | 31q | +283.7%+$389.2M |
| FARALLON CAPITAL MANAGEMENT, L.L.C. | $449.0M | 10,521,184 | 2.07% | 24q | +40.8%+$130.2M |
| DZ BANK AG Deutsche Zentral Genossenschafts Bank, Frankfurt am Main | $434.2M incl. $40.3M options CALL | 9,227,707 | 0.33% | 32q | -30.2%-$188.3M |
| CITADEL ADVISORS LLC | $433.4M incl. $220.6M options CALL+PUT | 4,987,748 | 0.05% | 31q | +18.3%+$66.9M |
| Legal & General Group Plc | $431.9M | 10,119,264 | 0.09% | 31q | -4.5%-$20.6M |
| AQR CAPITAL MANAGEMENT LLC | $413.2M | 9,681,750 | 0.14% | 31q | +84.8%+$189.6M |
| CANADA PENSION PLAN INVESTMENT BOARD | $395.3M | 9,262,404 | 0.22% | 31q | +15.3%+$52.3M |
| CHARLES SCHWAB INVESTMENT MANAGEMENT INC | $393.6M | 9,223,151 | 0.05% | 31q | +0.6%+$2.3M |
| Qube Research & Technologies Ltd | $391.0M incl. $9.3M options CALL+PUT | 8,943,771 | 0.36% | 15q | +60.6%+$147.5M |
| Nuveen, LLC | $371.1M | 8,695,119 | 0.09% | 6q | -25.9%-$129.7M |
| Assenagon Asset Management S.A. | $356.3M | 8,347,118 | 0.22% | 24q | -17.0%-$73.0M |
| VANGUARD FIDUCIARY TRUST CO | $356.2M | 8,345,428 | 0.08% | 2q | HELD |
| ROYAL BANK OF CANADA | $345.8M incl. $85.0K options PUT | 8,100,653 | 0.05% | 31q | +29.1%+$78.0M |
| Bank of New York Mellon Corp | $339.0M | 7,943,553 | 0.06% | 31q | -16.8%-$68.3M |
| BNP PARIBAS FINANCIAL MARKETS | $332.6M incl. $7.4M options CALL | 7,620,469 | 0.12% | 31q | +49.4%+$109.9M |
| PRICE T ROWE ASSOCIATES INC /MD/ | $301.8M | 7,070,412 | 0.03% | 31q | -10.2%-$34.3M |
| SUSQUEHANNA INTERNATIONAL GROUP, LLP | $279.7M incl. $208.8M options CALL+PUT | 1,661,950 | 0.02% | 31q | +60.9%+$105.8M |
| DEUTSCHE BANK AG\ | $254.2M | 5,957,053 | 0.07% | 34q | -10.5%-$29.7M |
| MAVERICK CAPITAL LTD | $253.4M | 5,937,553 | 2.24% | 3q | +41.5%+$74.4M |
| Ensign Peak Advisors, Inc | $251.0M | 5,881,367 | 0.41% | 27q | +30.5%+$58.6M |
| DIMENSIONAL FUND ADVISORS LP | $248.6M | 5,824,298 | 0.05% | 31q | -4.5%-$11.7M |
| MILLENNIUM MANAGEMENT LLC | $232.1M incl. $21.4M options CALL+PUT | 5,437,567 | 0.08% | 31q | +25.4%+$46.9M |
| BNP PARIBAS ASSET MANAGEMENT Holding S.A. | $229.7M | 5,380,866 | 0.23% | 31q | -22.8%-$67.7M |
| LAZARD ASSET MANAGEMENT LLC | $228.1M | 5,343,777 | 0.35% | 33q | +9.5%+$19.8M |
| AMERIPRISE FINANCIAL INC | $219.1M | 5,134,220 | 0.04% | 31q | -7.9%-$18.7M |
| Clearbridge Investments, LLC | $219.0M | 5,130,774 | 0.18% | 15q | +125.1%+$121.7M |
| Holocene Advisors, LP | $214.9M incl. $180.4M options CALL | 806,732 | 0.48% | 14q | -76.5%-$698.3M |
| Vontobel Holding Ltd. | $214.4M incl. $6.5M options CALL | 4,871,518 | 0.68% | 23q | -38.9%-$136.7M |
| SCHRODER INVESTMENT MANAGEMENT GROUP | $200.9M | 4,708,211 | 0.14% | 31q | -35.1%-$108.6M |
| BARCLAYS PLC | $200.3M incl. $4.7M options CALL | 4,584,260 | 0.04% | 31q | -8.8%-$19.2M |
| Swiss National Bank | $178.9M | 4,191,800 | 0.09% | 31q | -3.7%-$6.8M |
| National Pension Service | $169.0M | 3,959,598 | 0.11% | 31q | +7.1%+$11.1M |
| Squarepoint Ops LLC | $168.9M incl. $99.5M options CALL+PUT | 1,624,929 | 0.19% | 24q | +2.2%+$3.6M |
| SG Americas Securities, LLC | $163.7M incl. $2.2M options PUT | 3,785,401 | 0.09% | 31q | +306.5%+$123.5M |
| Mitsubishi UFJ Asset Management Co., Ltd. | $154.4M | 3,617,472 | 0.09% | 31q | +7.5%+$10.8M |
| HSBC HOLDINGS PLC | $150.6M | 3,533,722 | 0.06% | 31q | +3.9%+$5.7M |
| Ninety One UK Ltd | $149.5M | 3,501,985 | 0.33% | 17q | -52.1%-$162.5M |
| Sumitomo Mitsui Trust Group, Inc. | $146.3M | 3,427,875 | 0.08% | 31q | HELD |
| Employees Provident Fund Board | $143.3M | 3,358,700 | 0.82% | 7q | +57.3%+$52.2M |
| Vanguard Global Advisers, LLC | $142.5M | 3,337,790 | 0.07% | 2q | +2.9%+$4.0M |
| VOLORIDGE INVESTMENT MANAGEMENT, LLC | $139.8M | 3,275,326 | 0.59% | 5q | +203.8%+$93.8M |
| Man Group plc | $137.7M | 3,225,164 | 0.22% | 15q | -13.3%-$21.1M |
| Caisse de depot et placement du Quebec | $133.2M | 3,120,394 | 0.19% | 31q | +110.1%+$69.8M |
| Alecta Tjanstepension Omsesidigt | $133.0M | 3,117,000 | 0.56% | 12q | +8.8%+$10.7M |
| Mirova US LLC | $132.4M | 3,101,478 | 1.42% | 3q | +40.8%+$38.3M |
| NOMURA HOLDINGS INC | $131.0M incl. $124.9M options CALL+PUT | 142,929 | 0.15% | 25q | -40.1%-$87.8M |
| Aberdeen Group plc | $130.9M | 3,066,626 | 0.18% | 31q | +10.9%+$12.8M |
| WELLS FARGO & COMPANY/MN | $130.2M | 3,051,613 | 0.02% | 31q | +2.7%+$3.4M |
| Russell Investments Group, Ltd. | $123.7M | 2,895,696 | 0.11% | 31q | +24.9%+$24.7M |
| VANGUARD ASSET MANAGEMENT, Ltd | $122.6M | 2,873,191 | 0.08% | 2q | +11.9%+$13.1M |
| Public Sector Pension Investment Board | $119.7M | 2,804,896 | 0.31% | 31q | +35.0%+$31.0M |
| DekaBank Deutsche Girozentrale | $115.7M | 1,844,793 | 0.20% | 31q | HELD |
| MANUFACTURERS LIFE INSURANCE COMPANY, THE | $115.3M | 2,702,583 | 0.09% | 31q | +2.8%+$3.1M |
| CITIGROUP INC | $114.7M incl. $4.5M options CALL+PUT | 2,582,561 | 0.04% | 31q | +63.8%+$44.7M |
| RHUMBLINE ADVISERS | $112.8M | 2,641,843 | 0.09% | 31q | -1.2%-$1.4M |
| NORDEA INVESTMENT MANAGEMENT AB | $110.9M | 2,610,440 | 0.09% | 31q | +96.3%+$54.4M |
| Rathbones Group PLC | $108.4M | 2,539,901 | 0.40% | 16q | -60.1%-$163.0M |
| MARSHALL WACE, LLP | $103.1M incl. $38.4K options PUT | 2,414,223 | 0.08% | 31q | -33.1%-$51.1M |
| RENAISSANCE TECHNOLOGIES LLC | $102.9M | 2,412,005 | 0.14% | 6q | -23.5%-$31.6M |
| Temasek Holdings (Private) Ltd | $102.4M | 2,399,426 | 0.27% | 7q | HELD |
| Pictet Asset Management Holding SA | $102.2M | 2,393,080 | 0.10% | 12q | -53.3%-$116.4M |
| Unisphere Establishment | $101.9M | 2,387,800 | 0.87% | 11q | -14.8%-$17.7M |
| CALIFORNIA STATE TEACHERS RETIREMENT SYSTEM | $96.9M | 2,270,596 | 0.09% | 31q | -1.3%-$1.3M |
| MILFORD FUNDS LTD | $92.6M | 2,169,484 | 1.51% | 3q | -1.8%-$1.7M |
| ALLIANCEBERNSTEIN L.P. | $91.3M | 1,455,619 | 0.03% | 31q | -10.5%-$10.7M |
| NEUBERGER BERMAN GROUP LLC | $91.3M incl. $550.6K options PUT | 2,126,406 | 0.06% | 31q | -69.9%-$212.4M |
| California Public Employees Retirement System | $87.4M | 2,047,848 | 0.05% | 31q | -9.4%-$9.1M |
| TUDOR INVESTMENT CORP ET AL | $84.1M incl. $21.1M options CALL+PUT | 1,477,637 | 0.12% | 14q | +133.6%+$48.1M |
| Phoenix Financial Ltd. | $83.8M | 1,962,730 | 0.57% | 24q | +26.6%+$17.6M |
| RAYMOND JAMES FINANCIAL INC | $82.1M | 1,923,305 | 0.02% | 7q | -36.5%-$47.2M |
| Caption Management, LLC | $79.7M incl. $66.4M options CALL+PUT | 312,050 | 0.37% | 7q | -16.7%-$15.9M |
Showing the largest 100 of 1,500 reported holders.
Q2 2026 in brief
In Q2 2026, 1,500 managers that file Form 13F reported holding Boston Scientific Corp (BSX), $60.7B in all, or about 92% of the shares outstanding. 153 managers opened a position and 344 sold out completely, against 1,691 holders the quarter before. Largest holders: Blackrock, Inc., Vanguard Capital Management Llc and State Street Corp. Largest new positions: 1832 Asset Management L.P. ($448.1M), Deerfield Management Company, L.P. ($56.1M) and Lgt Capital Partners Ltd. ($39.1M).
Q2 2026 is the latest quarter whose 13F deadline has passed. A 13F shows long US stock positions at quarter end, filed up to 45 days later; an adviser and a sub-adviser can both report the same shares.
What the company announced
Form 8-K filings from the last 120 days, showing only the items worth a reader's attention. Earnings releases, exhibit attachments and general disclosures are filed constantly and are left out. Filed is when the SEC received it; event is the date the company says the thing happened.
| Filed | Event date | What | Source |
|---|---|---|---|
| 2026-10-07 | 2026-10-01 | Directors or officers departed or appointed | filing |
| 2026-09-23 | 2026-09-21 | Directors or officers departed or appointed | filing |
What the insiders did
Open market purchases and sales reported on Form 4 in the last 180 days. Grants, option exercises and shares surrendered to cover tax are left out: they are compensation rather than a decision to buy or sell. Where a broker filled one order in tranches the lines are summed, because it was one decision.
Officers and directors
| Date | Insider | Role | Side | Shares | Value |
|---|---|---|---|---|---|
| 2026-08-03 | Mahoney Michael F | Chairman, President & CEO | Bought | 186,240 | $9.0M |
| 2026-07-31 | LUDWIG EDWARD J | Director | Bought | 5,000 | $227.4K |
| 2026-05-20 | LUDWIG EDWARD J | Director | Bought | 3,580 | $202.9K |
| 2026-05-20 | Habiger David C | Director | Bought | 2,250 | $125.8K |
| 2026-05-19 | Habiger David C | Director | Bought | 2,200 | $125.3K |
| 2026-08-25 | Morano Susan E | Director | Bought | 2,040 | $100.4K |
Quarter by quarter
Coverage begins with the quarter ending 2018-12-31. Earlier filings exist only as occasional late amendments, too sparse to describe a market, so they are not shown.
| Quarter | Holders | Value | Shares | New | Added | Trimmed | Options |
|---|---|---|---|---|---|---|---|
| Q3 2026 | 478 | $1.9B | 42,862,975 | 75 | 167 | 164 | 0.3% |
| Q2 2026 | 1,500 | $60.7B | 1,334,423,712 | 143 | 578 | 614 | 5.3% |
| Q1 2026 | 1,691 | $86.6B | 1,345,024,836 | 176 | 658 | 605 | 2.5% |
| Q4 2025 | 1,798 | $132.5B | 1,371,522,247 | 134 | 634 | 647 | 1.4% |
| Q3 2025 | 1,720 | $136.6B | 1,378,254,585 | 160 | 718 | 512 | 1.6% |
| Q2 2025 | 1,706 | $148.1B | 1,361,538,486 | 133 | 708 | 523 | 1.3% |
| Q1 2025 | 1,658 | $138.0B | 1,350,682,337 | 210 | 642 | 517 | 1.4% |
| Q4 2024 | 1,532 | $121.7B | 1,343,666,286 | 123 | 575 | 465 | 1.4% |
| Q3 2024 | 1,413 | $114.9B | 1,350,780,772 | 151 | 532 | 437 | 1.4% |
| Q2 2024 | 1,334 | $106.0B | 1,357,397,946 | 152 | 519 | 392 | 1.4% |
| Q1 2024 | 1,237 | $96.5B | 1,395,293,509 | 144 | 413 | 425 | 1.0% |
| Q4 2023 | 1,159 | $81.2B | 1,386,407,906 | 103 | 415 | 350 | 1.3% |
| Q3 2023 | 1,068 | $71.6B | 1,339,159,314 | 86 | 414 | 324 | 1.3% |
| Q2 2023 | 1,075 | $72.3B | 1,325,278,151 | 125 | 377 | 331 | 0.9% |
| Q1 2023 | 1,006 | $72.0B | 1,429,099,395 | 129 | 366 | 296 | 0.7% |
| Q4 2022 | 934 | $61.0B | 1,308,094,291 | 107 | 281 | 321 | 0.8% |
| Q3 2022 | 852 | $201.7B | 6,369,409,473 | 74 | 302 | 267 | 0.2% |
| Q2 2022 | 865 | $196.6B | 6,263,605,518 | 69 | 301 | 291 | 0.3% |
| Q1 2022 | 898 | $159.6B | 4,588,544,966 | 92 | 334 | 271 | 0.4% |
| Q4 2021 | 892 | $96.3B | 2,753,390,763 | 75 | 277 | 295 | 1.8% |
| Q3 2021 | 878 | $119.3B | 3,894,288,755 | 77 | 310 | 264 | 1.4% |
| Q2 2021 | 869 | $106.3B | 3,023,440,308 | 97 | 278 | 287 | 1.5% |
| Q1 2021 | 825 | $87.9B | 3,059,139,329 | 75 | 276 | 286 | 0.6% |
| Q4 2020 | 865 | $85.3B | 2,916,749,619 | 83 | 318 | 275 | 0.8% |
| Q3 2020 | 848 | $95.8B | 3,477,258,078 | 74 | 304 | 286 | 0.5% |
| Q2 2020 | 839 | $87.2B | 3,139,243,413 | 106 | 335 | 240 | 0.6% |
| Q1 2020 | 797 | $105.9B | 4,279,191,659 | 80 | 277 | 297 | 0.4% |
| Q4 2019 | 851 | $101.5B | 2,718,246,762 | 98 | 271 | 258 | 0.4% |
| Q3 2019 | 770 | $80.1B | 2,059,582,332 | 82 | 247 | 266 | 0.5% |
| Q2 2019 | 753 | $87.3B | 2,181,902,610 | 71 | 266 | 239 | 0.6% |
| Q1 2019 | 794 | $72.2B | 1,972,922,609 | 103 | 282 | 234 | 0.3% |
| Q4 2018 | 736 | $80.0B | 2,486,668,259 | 11 | 13 | 12 | 0.3% |