Boston Scientific Corporation
US ˙ NYSE ˙ US1011371077

SecurityBSX / Boston Scientific Corporation
InstitutionAssociated Banc-corp
Latest Disclosed Ownership480,358 shares
Latest Disclosed Value $ 30,142,464
Associated Banc-corp reports 28.50% increase in ownership of BSX / Boston Scientific Corporation

On May 1, 2026 - Associated Banc-corp filed a 13F-HR form disclosing ownership of 480,358 shares of Boston Scientific Corporation (US:BSX) valued at $30,142,464 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 6, 2026 disclosing 373,832 shares of Boston Scientific Corporation. This represents a change in shares of 28.50% during the quarter. The current value of the position is $22,908,273 USD.

Institutional Ownership: 13F and NPORT Filings

The Security and Class in the table below are shown exactly as filed by the investor. We do our best to track continuity of investments through acquisitions, and this will be reflected in the table as changes in names. In addition to descriptive data, performance of the investment is shown over time. To calculate quarterly performance, we first calculate cost basis of the shares purchased during the quarter, then use that to calculate gross profit. Quarterly return is Gross Profit / Starting Portfolio value.

Note that cost basis is calculated and stored in thousands, so small quarterly changes in shares frequently result in a cost basis of zero.

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Disclosed Equity Positions (from 13F/NPORT Filings)
File
Date
Effective
Date
Form Security Class ID Avg Price
Paid (Est)
Reported
Shares
ΔShares ΔShares
(%)
Reported
Value
(x1000)
ΔValue
(%)
Alloc
(%)
ΔAlloc ΔAlloc (%) Cost Basis
(x1000)
Unrealized
Gain/Loss
(x1000)
2026-05-01 2026-03-31 13F BOSTON SCIENTIFIC COM 101137107 480,358 106,526 28.50 30,142 -15.44 0.7981
2026-02-06 2025-12-31 13F BOSTON SCIENTIFIC COM 101137107 373,832 1,389 0.37 35,645 -1.97 0.9125
2025-10-24 2025-09-30 13F BOSTON SCIENTIFIC COM 101137107 372,443 383 0.10 36,362 -9.01 0.9570
2025-08-12 2025-06-30 13F BOSTON SCIENTIFIC COM 101137107 372,060 -2,821 -0.75 39,963 5.67 1.1327
2025-05-09 2025-03-31 13F BOSTON SCIENTIFIC COM 101137107 374,881 -48,370 -11.43 37,818 0.03 1.1531
2025-02-10 2024-12-31 13F BOSTON SCIENTIFIC COM 101137107 423,251 537 0.13 37,805 6.72 1.1389
2024-11-13 2024-09-30 13F BOSTON SCIENTIFIC COM 101137107 422,714 -1,539 -0.36 35,423 8.42 1.0413
2024-08-01 2024-06-30 13F BOSTON SCIENTIFIC COM 101137107 424,253 -12,860 -2.94 32,672 9.13 1.0161
2024-05-09 2024-03-31 13F BOSTON SCIENTIFIC COM 101137107 437,113 8,116 1.89 29,938 20.71 0.9490
2024-02-09 2023-12-31 13F BOSTON SCIENTIFIC COM 101137107 428,997 -1,191 -0.28 24,800 9.19 0.8616
2023-11-09 2023-09-30 13F BOSTON SCIENTIFIC COM 101137107 430,188 4,497 1.06 22,714 -1.36 0.8792
2023-08-07 2023-06-30 13F BOSTON SCIENTIFIC COM 101137107 425,691 -19,025 -4.28 23,026 3.49 0.8702
2023-05-09 2023-03-31 13F BOSTON SCIENTIFIC COM 101137107 444,716 3,584 0.81 22,249 9.00 0.8938
2023-02-10 2022-12-31 13F BOSTON SCIENTIFIC COM 101137107 441,132 16,845 3.97 20,411 24.21 0.8494
2022-11-09 2022-09-30 13F BOSTON SCIENTIFIC COM 101137107 424,287 5,468 1.31 16,432 5.27 0.7593
2022-08-10 2022-06-30 13F BOSTON SCIENTIFIC COM 101137107 418,819 692 0.17 15,610 -15.70 0.6834
2022-05-11 2022-03-31 13F BOSTON SCIENTIFIC COM 101137107 418,127 -6,830 -1.61 18,518 2.58 0.7131
2022-02-10 2021-12-31 13F BOSTON SCIENTIFIC COM 101137107 424,957 -5,287 -1.23 18,052 -3.30 0.6619
2021-11-08 2021-09-30 13F BOSTON SCIENTIFIC COM 101137107 430,244 7,555 1.79 18,668 3.29 0.7377
2021-08-11 2021-06-30 13F BOSTON SCIENTIFIC COM 101137107 422,689 -110,389 -20.71 18,074 3.91 0.7151
2021-05-05 2021-03-31 13F BOSTON SCIENTIFIC COM 101137107 533,078 10,840 2.08 17,394 -7.36 1.0813
2021-02-11 2020-12-31 13F BOSTON SCIENTIFIC COM 101137107 522,238 -12,572 -2.35 18,775 -8.12 0.7327
2020-11-12 2020-09-30 13F BOSTON SCIENTIFIC COM 101137107 534,810 -18,933 -3.42 20,435 5.11 0.8791
2020-08-14 2020-06-30 13F BOSTON SCIENTIFIC COM 101137107 553,743 20,665 3.88 19,442 11.77 0.8774
2020-05-14 2020-03-31 13F BOSTON SCIENTIFIC COM 101137107 533,078 40,178 8.15 17,394 -21.96 0.9271
2020-02-12 2019-12-31 13F BOSTON SCIENTIFIC COM 101137107 492,900 6,524 1.34 22,289 12.62 1.1102
2019-11-14 2019-09-30 13F BOSTON SCIENTIFIC COM 101137107 486,376 12,422 2.62 19,791 -2.85 1.0642
2019-08-06 2019-06-30 13F BOSTON SCIENTIFIC COM 101137107 473,954 33,202 7.53 20,371 20.42 1.1167
2019-05-07 2019-03-31 13F BOSTON SCIENTIFIC COM 101137107 440,752 22,107 5.28 16,916 14.34 0.9750
2019-02-13 2018-12-31 13F BOSTON SCIENTIFIC COM 101137107 418,645 -1,935 -0.46 14,795 -8.63 0.9645
2018-11-07 2018-09-30 13F BOSTON SCIENTIFIC COM 101137107 420,580 12,075 2.96 16,192 21.21 0.8982
2018-08-07 2018-06-30 13F BOSTON SCIENTIFIC COM 101137107 408,505 -11,548 -2.75 13,359 16.41 0.7810
2018-05-07 2018-03-31 13F BOSTON SCIENTIFIC COM 101137107 420,053 80,673 23.77 11,476 36.39 0.6527
2018-02-07 2017-12-31 13F BOSTON SCIENTIFIC COM 101137107 339,380 35,163 11.56 8,414 -5.18 0.4538
2017-11-13 2017-09-30 13F BOSTON SCIENTIFIC COM 101137107 304,217 304,217 8,874 0.4895
Legend
Shares
The total number of shares held by the institution at the end of the reporting period (the effective date). This is provided in the filing.
Value
The total value of the shares as of the effective date. This is provided in the filing.
Avg. Share Price
The weighted average share price of the shares held by the institution. We use FIFO accounting to determine this price
Class
This is the security class as indicated by the filer. There are a variety of values for this field. Common values include "EC" = equity common, "EP" - equity preferred
Allocation (%)
The percent of the institution's portfolio that this position represents. This is provided in NPORT filings. For 13F filings, we calculate it.
Change in Allocation
The change in allocation from the prior reporting period. This is calculated as current allocation - prior allocation.
Change in Allocation (%)
The percent change in allocation from the prior reporting period. This is calculated as (current allocation - prior allocation) / prior allocation.
Cost Basis
The total cost of the shares held. This is calculated as reported shares * avg. share price
Unrealized Gain/Loss
This is the market value of the position as of the effective date minus the cost basis.