Simpson Manufacturing Co., Inc.
US ˙ NYSE ˙ US8290731053

SecuritySSD / Simpson Manufacturing Co., Inc.
InstitutionWhittier Trust Co
Latest Disclosed Ownership97,529 shares
Latest Disclosed Value $ 16,346,836
Whittier Trust Co reports 10.01% increase in ownership of SSD / Simpson Manufacturing Co., Inc.

On April 28, 2026 - Whittier Trust Co filed a 13F-HR form disclosing ownership of 97,529 shares of Simpson Manufacturing Co., Inc. (US:SSD) valued at $16,737,927 USD as of March 31, 2026. The entity filed a previous 13F-HR on January 26, 2026 disclosing 88,652 shares of Simpson Manufacturing Co., Inc.. This represents a change in shares of 10.01% during the quarter. The current value of the position is $18,219,392 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)
2026-04-28 2026-03-31 13F SIMPSON MANUFACTUR common 829073105 97,529 8,877 10.01 16,347 8.33 0.1845
2026-01-26 2025-12-31 13F SIMPSON MANUFACTUR common 829073105 88,652 -112 -0.13 15,089 -0.72 0.1634
2025-10-31 2025-09-30 13F SIMPSON MFG common 829073105 88,764 1,427 1.63 15,198 12.05 0.1730
2025-07-30 2025-06-30 13F SIMPSON MANUFACTURING CO INCCOM US SMALL-CAP EQUITIES 829073105 87,337 1,979 2.32 13,564 1.17 0.1636
2025-05-02 2025-03-31 13F SIMPSON MANUFACTURING CO INCCOM US SMALL-CAP EQUITIES 829073105 85,358 1,678 2.01 13,408 -3.38 0.1868
2025-02-11 2024-12-31 13F SIMPSON MANUFACTURING CO INCCOM US SMALL-CAP EQUITIES 829073105 83,680 2,819 3.49 13,876 -10.28 0.1828
2024-10-21 2024-09-30 13F SIMPSON MANUFACTURING CO INCCOM US SMALL-CAP EQUITIES 829073105 80,861 3,283 4.23 15,466 18.30 0.2070
2024-07-29 2024-06-30 13F SIMPSON MANUFACTURING CO INCCOM US SMALL-CAP EQUITIES 829073105 77,578 -11,281 -12.70 13,074 -28.29 0.1855
2024-05-02 2024-03-31 13F SIMPSON MANUFACTURING CO INCCOM US SMALL-CAP EQUITIES 829073105 88,859 3,352 3.92 18,232 7.70 0.2658
2024-01-11 2023-12-31 13F SIMPSON MANUFACTURING CO INCCOM US SMALL-CAP EQUITIES 829073105 85,507 2,219 2.66 16,929 35.67 0.2744
2023-10-27 2023-09-30 13F SIMPSON MANUFACTURING CO INCCOM US SMALL-CAP EQUITIES 829073105 83,288 2,535 3.14 12,477 11.56 0.2217
2023-07-24 2023-06-30 13F SIMPSON MANUFACTURING CO INCCOM US SMALL-CAP EQUITIES 829073105 80,753 4,005 5.22 11,184 32.92 0.1944
2023-04-21 2023-03-31 13F SIMPSON MANUFACTURING CO INCCOM US SMALL-CAP EQUITIES 829073105 76,748 730 0.96 8,415 24.87 0.1532
2023-01-25 2022-12-31 13F SIMPSON MANUFACTURING CO INCCOM US SMALL-CAP EQUITIES 829073105 76,018 -16,657 -17.97 6,739 -7.27 0.1311
2022-10-21 2022-09-30 13F SIMPSON MANUFACTURING CO INCCOM US SMALL-CAP EQUITIES 829073105 92,675 3,358 3.76 7,266 -19.14 0.1523
2022-07-28 2022-06-30 13F SIMPSON MANUFACTURING CO INCCOM US SMALL-CAP EQUITIES 829073105 89,317 336 0.38 8,986 -7.38 0.1815
2022-04-29 2022-03-31 13F SIMPSON MANUFACTURING CO INCCOM US SMALL-CAP EQUITIES 829073105 88,981 3,666 4.30 9,702 -18.22 0.1636
2022-01-19 2021-12-31 13F SIMPSON MANUFACTURING CO INCCOM US SMALL-CAP EQUITIES 829073105 85,315 2,207 2.66 11,864 33.45 0.1928
2021-11-01 2021-09-30 13F SIMPSON MANUFACTURING CO INCCOM US SMALL-CAP EQUITIES 829073105 83,108 3,497 4.39 8,890 1.11 0.1619
2021-07-29 2021-06-30 13F SIMPSON MANUFACTURING CO INCCOM US SMALL-CAP EQUITIES 829073105 79,611 4,428 5.89 8,792 12.73 0.1566
2021-04-26 2021-03-31 13F SIMPSON MANUFACTURING CO INCCOM US SMALL-CAP EQUITIES 829073105 75,183 5,466 7.84 7,799 19.71 0.1515
2021-01-29 2020-12-31 13F SIMPSON MANUFACTURING CO INCCOM US SMALL-CAP EQUITIES 829073105 69,717 2,833 4.24 6,515 0.26 0.1392
2020-10-30 2020-09-30 13F SIMPSON MANUFACTURING CO INCCOM US SMALL-CAP EQUITIES 829073105 66,884 1,654 2.54 6,498 18.08 0.1547
2020-07-10 2020-06-30 13F SIMPSON MANUFACTURING CO INCCOM US SMALL-CAP EQUITIES 829073105 65,230 -715 -1.08 5,503 34.68 0.1528
2020-04-27 2020-03-31 13F SIMPSON MANUFACTURING CO INCCOM US SMALL-CAP EQUITIES 829073105 65,945 2,714 4.29 4,086 -19.44 0.1334
2020-01-31 2019-12-31 13F SIMPSON MANUFACTURING CO INCCOM US SMALL-CAP EQUITIES 829073105 63,231 1,063 1.71 5,072 17.63 0.1331
2019-10-18 2019-09-30 13F SIMPSON MANUFACTURING CO INCCOM US SMALL-CAP EQUITIES 829073105 62,168 485 0.79 4,312 5.20 0.1234
2019-07-23 2019-06-30 13F SIMPSON MANUFACTURING CO INCCOM US SMALL-CAP EQUITIES 829073105 61,683 1,923 3.22 4,099 15.73 0.1204
2019-04-29 2019-03-31 13F SIMPSON MANUFACTURING CO INCCOM US SMALL-CAP EQUITIES 829073105 59,760 1,899 3.28 3,542 13.09 0.1083
2019-02-07 2018-12-31 13F SIMPSON MANUFACTURING CO INCCOM US SMALL-CAP EQUITIES 829073105 57,861 19,269 49.93 3,132 12.02 0.1078
2018-10-23 2018-09-30 13F SIMPSON MANUFACTURING CO INCCOM US SMALL-CAP EQUITIES 829073105 38,592 162 0.42 2,796 16.99 0.0872
2018-07-27 2018-06-30 13F/A-1 SIMPSON MANUFACTURING CO INCCOM US SMALL-CAP EQUITIES 829073105 38,430 1,710 4.66 2,390 13.00 0.0790
2018-07-20 2018-06-30 13F SIMPSON MANUFACTURING CO INCCOM US SMALL AND MID-CAP EQUITIES 829073105 31,726 -4,994 1,154
2018-05-01 2018-03-31 13F SIMPSON MANUFACTURING CO INCCOM US SMALL-CAP EQUITIES 829073105 36,720 327 0.90 2,115 1.24 0.0711
2018-02-07 2017-12-31 13F SIMPSON MANUFACTURING CO INCCOM US SMALL-CAP EQUITIES 829073105 36,393 765 2.15 2,089 19.58 0.0729
2017-10-23 2017-09-30 13F SIMPSON MANUFACTURING CO INCCOM US SMALL-CAP EQUITIES 829073105 35,628 505 1.44 1,747 13.81 0.0637
2017-07-20 2017-06-30 13F SIMPSON MANUFACTURING CO INCCOM US SMALL-CAP EQUITIES 829073105 35,123 868 2.53 1,535 4.00 0.0593
2017-04-26 2017-03-31 13F SIMPSON MANUFACTURING US SMALL AND MID-CAP EQUITIES 829073105 34,255 1,556 4.76 1,476 3.14 0.0595
2017-01-18 2016-12-31 13F SIMPSON MANUFACTURING CO INCCOM US SMALL AND MID-CAP EQUITIES 829073105 32,699 181 0.56 1,431 0.14 0.0609
2016-11-10 2016-09-30 13F SIMPSON MANUFACTURING CO INCCOM US SMALL AND MID-CAP EQUITIES 829073105 32,518 66 0.20 1,429 10.18 0.0622
2016-07-28 2016-06-30 13F SIMPSON MANUFACTURING CO INCCOM US SMALL AND MID-CAP EQUITIES 829073105 32,452 392 1.22 1,297 6.05 0.0571
2016-04-28 2016-03-31 13F SIMPSON MANUFACTURING CO INCCOM US SMALL AND MID-CAP EQUITIES 829073105 32,060 0 0.00 1,223 11.69 0.0541
2016-02-10 2015-12-31 13F SIMPSON MANUFACTURING CO INCCOM US SMALL AND MID-CAP EQUITIES 829073105 32,060 334 1.05 1,095 3.11 0.0497
2015-11-12 2015-09-30 13F SIMPSON MANUFACTURING CO INCCOM US SMALL AND MID-CAP EQUITIES 829073105 31,726 0 0.00 1,062 -1.58 0.0517
2015-08-13 2015-06-30 13F SIMPSON MANUFACTURING CO INCCOM US SMALL AND MID-CAP EQUITIES 829073105 31,726 0 0.00 1,079 -8.95 0.0479
2015-05-05 2015-03-31 13F SIMPSON MANUFACTURING CO INCCOM US SMALL AND MID-CAP EQUITIES 829073105 31,726 31,726 0.00 1,185 0.0543
2015-02-04 2014-12-31 13F SIMPSON MANUFACTURING CO INCCOM US SMALL AND MID-CAP EQUITIES 829073105 0 -31,726 -100.00 0 -100.00
2014-11-07 2014-09-30 13F SIMPSON MANUFACTURING CO INCCOM US SMALL AND MID-CAP EQUITIES 829073105 31,726 0 0.00 924 -19.93 0.0450
2014-08-04 2014-06-30 13F SIMPSON MANUFACTURING CO INCCOM US SMALL AND MID-CAP EQUITIES 829073105 31,726 0 0.00 1,154 2.94 0.0569
2014-05-01 2014-03-31 13F SIMPSON MANUFACTURING CO INCCOM US SMALL AND MID-CAP EQUITIES 829073105 31,726 0 0.00 1,121 -3.78 0.0574
2014-02-05 2013-12-31 13F SIMPSON MANUFACTURING CO INCCOM US SMALL AND MID-CAP EQUITIES 829073105 31,726 -10,000 -23.97 1,165 -14.28 0.0597
2013-11-18 2013-09-30 13F SIMPSON MANUFACTURING COM 829073105 41,726 0 0.00 1,359 10.76 0.0735
2013-08-14 2013-06-30 13F SIMPSON MANUFACTURING COM 829073105 41,726 41,726 1,227 0.0688
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.