Builders FirstSource, Inc.
US ˙ NYSE ˙ US12008R1077

SecurityBLDR / Builders FirstSource, Inc.
InstitutionDiametric Capital, LP
Latest Disclosed Ownership4,441 shares
Latest Disclosed Value $ 365,627
Diametric Capital, LP reports 103.44% increase in ownership of BLDR / Builders FirstSource, Inc.

On May 15, 2026 - Diametric Capital, LP filed a 13F-HR form disclosing ownership of 4,441 shares of Builders FirstSource, Inc. (US:BLDR) valued at $365,628 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 13, 2026 disclosing 2,183 shares of Builders FirstSource, Inc.. This represents a change in shares of 103.44% during the quarter. The current value of the position is $329,789 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 BUILDERS FIRSTSOURCE COM 12008R107 4,441 2,258 103.44 366 62.95 0.0950
2026-02-13 2025-12-31 13F BUILDERS FIRSTSOURCE COM 12008R107 2,183 -1,242 -36.26 225 -46.02 0.0602
2025-11-13 2025-09-30 13F BUILDERS FIRSTSOURCE COM 12008R107 3,425 789 29.93 415 35.18 0.1540
2025-08-13 2025-06-30 13F BUILDERS FIRSTSOURCE COM 12008R107 2,636 2,636 308 0.1641
2025-02-12 2024-12-31 13F BUILDERS FIRSTSOURCE COM 12008R107 0 -1,169 -100.00 0 -100.00
2024-11-13 2024-09-30 13F BUILDERS FIRSTSOURCE COM 12008R107 1,169 1,169 227 0.1120
2024-08-13 2024-06-30 13F BUILDERS FIRSTSOURCE COM 12008R107 0 -1,294 -100.00 0 -100.00
2024-05-15 2024-03-31 13F BUILDERS FIRSTSOURCE COM 12008R107 1,294 1,294 270 0.1499
2023-05-11 2023-03-31 13F Builders FirstSource COM 12008R107 0 -4,896 -100.00 0 -100.00
2023-03-29 2022-12-31 13F Builders FirstSource COM 12008R107 4,896 670 15.85 318 27.31 0.1529
2022-11-14 2022-09-30 13F BUILDERS FIRSTSOURCE COM 12008R107 4,226 4,226 249 0.1255
2022-08-15 2022-06-30 13F Builders FirstSource COM 12008R107 0 -23,474 -100.00 0 -100.00
2022-05-16 2022-03-31 13F Builders FirstSource COM 12008R107 23,474 -34,716 -59.66 1,515 -69.62 0.8362
2022-02-14 2021-12-31 13F Builders FirstSource COM 12008R107 58,190 43,256 289.65 4,987 545.15 3.8182
2021-11-15 2021-09-30 13F Builders FirstSource COM 12008R107 14,934 14,934 773 0.6096
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.