빌더스 FirstSource, Inc.
MX ˙ BMV ˙ US12008R1077
SecurityMX:BLDR / Builders FirstSource, Inc.
InstitutionAmalgamated Bank
Latest Disclosed Ownership20,047 shares
Latest Disclosed Value $ 1,650
Amalgamated Bank reports 12.24% decrease in ownership of BLDR / Builders FirstSource, Inc.

On May 8, 2026 - Amalgamated Bank filed a 13F-HR form disclosing ownership of 20,047 shares of Builders FirstSource, Inc. (MX:BLDR) valued at $1,650 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 5, 2026 disclosing 22,844 shares of Builders FirstSource, Inc.. This represents a change in shares of -12.24% during the quarter.

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)
2026-05-08 2026-03-31 13F BUILDERS FIRSTSOURCE INC COM COM 12008R107 20,047 -2,797 -12.24 2 -50.00 0.0126
2026-02-05 2025-12-31 13F BUILDERS FIRSTSOURCE INC COM COM 12008R107 22,844 2,171 10.50 2 0.00 0.0170
2025-10-29 2025-09-30 13F BUILDERS FIRSTSOURCE INC COM COM 12008R107 20,673 -795 -3.70 3 0.00 0.0179
2025-08-04 2025-06-30 13F BUILDERS FIRSTSOURCE INC COM COM 12008R107 21,468 -1,003 -4.46 3 0.00 0.0193
2025-04-25 2025-03-31 13F BUILDERS FIRSTSOURCE INC COM COM 12008R107 22,471 38 0.17 3 -33.33 0.0240
2025-02-04 2024-12-31 13F BUILDERS FIRSTSOURCE INC COM COM 12008R107 22,433 -795 -3.42 3 -25.00 0.0263
2024-10-30 2024-09-30 13F BUILDERS FIRSTSOURCE INC COM COM 12008R107 23,228 -11,886 -33.85 5 0.00 0.0371
2024-08-12 2024-06-30 13F BUILDERS FIRSTSOURCE INC COM COM 12008R107 35,114 -7,615 -17.82 5 -50.00 0.0414
2024-04-23 2024-03-31 13F BUILDERS FIRSTSOURCE INC COM COM 12008R107 42,729 -10,960 -20.41 9 0.00 0.0762
2024-02-06 2023-12-31 13F BUILDERS FIRSTSOURCE INC COM COM 12008R107 53,689 -43,433 -44.72 9 -33.33 0.0715
2023-11-08 2023-09-30 13F BUILDERS FIRSTSOURCE INC COM COM 12008R107 97,122 11,721 13.72 12 9.09 0.1029
2023-08-11 2023-06-30 13F BUILDERS FIRSTSOURCE INC COM COM 12008R107 85,401 -15,465 -15.33 12 37.50 0.0940
2023-05-02 2023-03-31 13F BUILDERS FIRSTSOURCE INC COM COM 12008R107 100,866 -32,633 -24.44 9 0.00 0.0763
2023-02-10 2022-12-31 13F BUILDERS FIRSTSOURCE INC COM COM 12008R107 133,499 19,510 17.12 9 -99.88 0.0772
2022-11-09 2022-09-30 13F BUILDERS FIRSTSOURCE INC COM COM 12008R107 113,989 -30,245 -20.97 6,716 -13.29 0.0648
2022-08-15 2022-06-30 13F BUILDERS FIRSTSOURCE INC COM COM 12008R107 144,234 11,965 9.05 7,745 -9.28 0.0722
2022-08-25 2022-03-31 13F/A-1 BUILDERS FIRSTSOURCE INC COM COM 12008R107 132,269 -5,069 -3.69 8,537 -27.47 0.0663
2022-06-30 2022-03-31 13F BUILDERS FIRSTSOURCE INC COM COM 12008R107 132,269 -5,069 8,537 0.0678
2022-02-15 2021-12-31 13F/A-1 BUILDERS FIRSTSOURCE INC COM COM 12008R107 137,338 -37,213 -21.32 11,771 30.34 0.0869
2022-02-15 2021-12-31 13F BUILDERS FIRSTSOURCE INC COM COM 12008R107 137,338 -37,213 11,771 0.0869
2021-10-29 2021-09-30 13F BUILDERS FIRSTSOURCE COM 12008R107 174,551 -14,911 -7.87 9,031 11.74 0.0763
2021-08-16 2021-06-30 13F BUILDERS FIRSTSOURCE COM 12008R107 189,462 164,763 667.08 8,082 605.85 0.0648
2021-05-13 2021-03-31 13F BUILDERS FIRSTSOURCE COM 12008R107 24,699 6,353 34.63 1,145 52.87 0.0429
2021-02-12 2020-12-31 13F BUILDERS FIRSTSOURCE COM 12008R107 18,346 162 0.89 749 26.31 0.0284
2020-10-30 2020-09-30 13F BUILDERS FIRSTSOURCE COM 12008R107 18,184 459 2.59 593 61.58 0.0258
2020-08-10 2020-06-30 13F BUILDERS FIRSTSOURCE COM 12008R107 17,725 -2,665 -13.07 367 47.39 0.0170
2020-05-13 2020-03-31 13F BUILDERS FIRSTSOURCE COM 12008R107 20,390 -941 -4.41 249 -54.06 0.0061
2020-02-13 2019-12-31 13F BUILDERS FIRSTSOURCE COM 12008R107 21,331 1,375 6.89 542 31.87 0.0100
2019-11-13 2019-09-30 13F BUILDERS FIRSTSOURCE COM 12008R107 19,956 -255 -1.26 411 20.53 0.0086
2019-08-14 2019-06-30 13F BUILDERS FIRSTSOURCE COM 12008R107 20,211 3,088 18.03 341 49.56 0.0080
2019-05-15 2019-03-31 13F BUILDERS FIRSTSOURCE COM 12008R107 17,123 415 2.48 228 25.27 0.0055
2019-02-15 2018-12-31 13F BUILDERS FIRSTSOURCE COM 12008R107 16,708 16,708 182 0.0052
2018-11-14 2018-09-30 13F BUILDERS FIRSTSOURCE COM 12008R107 0 -17,260 -100.00 0 -100.00
2018-07-18 2018-06-30 13F BUILDERS FIRSTSOURCE COM 12008R107 17,260 2,501 16.95 316 7.85 0.0077
2018-05-22 2018-03-31 13F BUILDERS FIRSTSOURCE COM 12008R107 14,759 -262 -1.74 293 -10.40 0.0078
2018-02-13 2017-12-31 13F BUILDERS FIRSTSOURCE COM 12008R107 15,021 2,729 22.20 327 47.96 0.0088
2017-11-09 2017-09-30 13F BUILDERS FIRSTSOURCE COM 12008R107 12,292 -158 -1.27 221 15.71 0.0069
2017-08-10 2017-06-30 13F BUILDERS FIRSTSOURCE COM 12008R107 12,450 2,178 21.20 191 24.84 0.0063
2017-05-12 2017-03-31 13F BUILDERS FIRSTSOURCE COM 12008R107 10,272 -17 -0.17 153 35.40 0.0076
2017-02-14 2016-12-31 13F BUILDERS FIRSTSOURCE COM 12008R107 10,289 10,289 113 0.0051
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.