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

SecuritySSD / Simpson Manufacturing Co., Inc.
InstitutionPort Capital LLC
Latest Disclosed Ownership408,069 shares
Latest Disclosed Value $ 70,032,802
Port Capital LLC reports 0.16% decrease in ownership of SSD / Simpson Manufacturing Co., Inc.

On May 15, 2026 - Port Capital LLC filed a 13F-HR form disclosing ownership of 408,069 shares of Simpson Manufacturing Co., Inc. (US:SSD) valued at $70,032,802 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 17, 2026 disclosing 408,705 shares of Simpson Manufacturing Co., Inc.. This represents a change in shares of -0.16% during the quarter. The current value of the position is $76,231,370 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)
2026-05-15 2026-03-31 13F SIMPSON MFG COM 829073105 408,069 -636 -0.16 70,033 6.12 3.1143
2026-02-17 2025-12-31 13F SIMPSON MFG COM 829073105 408,705 2,495 0.61 65,994 -2.99 2.8462
2025-11-14 2025-09-30 13F SIMPSON MFG COM 829073105 406,210 3,825 0.95 68,024 8.85 2.8350
2025-08-14 2025-06-30 13F SIMPSON MFG COM 829073105 402,385 23,620 6.24 62,494 5.04 2.6575
2025-05-15 2025-03-31 13F SIMPSON MFG COM 829073105 378,765 2,885 0.77 59,496 -4.55 2.6975
2025-02-14 2024-12-31 13F SIMPSON MFG COM 829073105 375,880 6,625 1.79 62,332 -11.74 2.8449
2024-11-14 2024-09-30 13F SIMPSON MFG COM 829073105 369,255 975 0.26 70,627 13.79 3.1655
2024-08-14 2024-06-30 13F SIMPSON MFG INC COM COM 829073105 368,280 1,150 0.31 62,066 -17.61 3.1097
2024-05-15 2024-03-31 13F SIMPSON MFG INC COM COM 829073105 367,130 11,005 3.09 75,328 6.84 3.7759
2024-02-15 2023-12-31 13F SIMPSON MFG INC COM COM 829073105 356,125 1,699 0.48 70,506 32.79 3.9333
2023-11-14 2023-09-30 13F SIMPSON MFG INC COM COM 829073105 354,426 -32,100 -8.30 53,097 -0.82 3.3140
2023-08-14 2023-06-30 13F SIMPSON MFG INC COM COM 829073105 386,526 17,275 4.68 53,534 32.23 3.2207
2023-05-15 2023-03-31 13F SIMPSON MFG INC COM COM 829073105 369,251 19,480 5.57 40,485 30.55 2.6310
2023-02-15 2022-12-31 13F SIMPSON MFG INC COM COM 829073105 349,771 22,683 6.93 31,011 20.93 2.2416
2022-11-14 2022-09-30 13F SIMPSON MFG INC COM COM 829073105 327,088 24,625 8.14 25,644 -15.73 2.0821
2022-08-15 2022-06-30 13F SIMPSON MFG INC COM COM 829073105 302,463 -7,185 -2.32 30,431 -9.87 2.3829
2022-05-16 2022-03-31 13F SIMPSON MFG INC COM COM 829073105 309,648 -16,010 -4.92 33,764 -25.45 2.3344
2022-02-14 2021-12-31 13F SIMPSON MFG INC COM COM 829073105 325,658 -249,208 -43.35 45,289 -26.35 2.7853
2021-11-15 2021-09-30 13F SIMPSON MFG INC COM COM 829073105 574,866 37,734 7.03 61,493 3.66 3.1040
2021-08-16 2021-06-30 13F SIMPSON MFG INC COM COM 829073105 537,132 23,080 4.49 59,321 11.25 3.0887
2021-05-17 2021-03-31 13F SIMPSON MFG INC COM COM 829073105 514,052 144,781 39.21 53,323 54.52 3.0189
2021-02-16 2020-12-31 13F SIMPSON MANUFACTURING CO INC C COM 829073105 369,271 160,598 76.96 34,508 70.20 2.3483
2020-11-16 2020-09-30 13F SIMPSON MANUFACTURING CO INC C COM 829073105 208,673 0 0.00 20,275 15.17 1.7468
2020-08-17 2020-06-30 13F/A-1 SIMPSON MANUFACTURING CO INC C COM 829073105 208,673 102,479 96.50 17,604 167.46 1.6965
2020-08-14 2020-06-30 13F SIMPSON MANUFACTURING CO INC C COM 829073105 148,448 42,254 12,523 1,451,529.7104
2020-05-15 2020-03-31 13F SIMPSON MANUFACTURING CO INC C COM 829073105 106,194 60,619 133.01 6,582 80.03 0.9155
2020-02-14 2019-12-31 13F SIMPSON MANUFACTURING CO INC C COM 829073105 45,575 2,775 6.48 3,656 23.14 0.4034
2019-11-14 2019-09-30 13F SIMPSON MANUFACTURING CO INC C COM 829073105 42,800 25,120 142.08 2,969 152.68 0.3388
2019-08-14 2019-06-30 13F SIMPSON MANUFACTURING CO INC C COM 829073105 17,680 17,680 1,175 0.1385
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.