Builders FirstSource, Inc.
MX ˙ BMV ˙ US12008R1077
SecurityMX:BLDR / Builders FirstSource, Inc.
InstitutionM&t Bank Corp
Latest Disclosed Ownership16,327 shares
Latest Disclosed Value $ 1,344,203
M&t Bank Corp ownership in BLDR / Builders FirstSource, Inc.

On May 12, 2026 - M&t Bank Corp filed a 13F-HR form disclosing ownership of 16,327 shares of Builders FirstSource, Inc. (MX:BLDR) valued at $1,344,203 USD as of March 31, 2026. The entity filed a previous 13F-HR/A on January 30, 2026 disclosing 16,113 shares of Builders FirstSource, Inc.. This represents a change in shares of 1.33% during the quarter.

M&t Bank Corp has a history of taking positions in derivatives of the underlying security (BLDR) in the form of stock options. The firm currently holds call options representing 0 of underlying shares valued at $0 USD .

Note: prior versions of this page mistakenly stated that the share values represented the number of options, not the number of underlying shares. For more information on the data backing these reports, please see the SEC document Frequently Asked Questions About Form 13F.

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.

Upgrade to unlock premium data and export to Excel .

Institutional Put/Call Ratios
(Premium Subscription Required)

In addition to reporting standard equity and debt issues, institutions with more than 100MM assets under management must also disclose their put and call option holdings. Since put options generally indicate negative sentiment, and call options indicate positive sentiment, we can get a sense of the overall institutional sentiment by plotting the ratio of puts to calls. The chart to the right plots the historical put/call ratio for this instrument.

Using Put/Call Ratio as an indicator of investor sentiment overcomes one of the key deficiencies of using total institutional ownership, which is that a significant amount of assets under management are invested passively to track indices. Passively-managed funds do not typically buy options, so the put/call ratio indicator more closely tracks the sentiment of actively-managed funds.

MX:BLDR / Builders FirstSource, Inc. Historical Put/Call Ratio
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)
2026-05-12 2026-03-31 13F BUILDERS FIRSTSOURCE COM 12008R107 16,327 214 1.33 1,344 -18.89 0.0011
2026-01-30 2025-12-31 13F/A-1 BUILDERS FIRSTSOURCE COM 12008R107 16,113 4,293 36.32 1,658 15.63 0.0053
2026-01-28 2025-12-31 13F BUILDERS FIRSTSOURCE COM 12008R107 13,671 1,851 896 0.0005
2025-11-14 2025-09-30 13F BUILDERS FIRSTSOURCE COM 12008R107 11,820 612 5.46 1,433 9.56 0.0048
2025-08-13 2025-06-30 13F BUILDERS FIRSTSOURCE COM 12008R107 11,208 6,967 164.28 1,309 147.26 0.0045
2025-04-30 2025-03-31 13F BUILDERS FIRSTSOURCE COM 12008R107 4,241 -1,152 -21.36 529 -31.30 0.0019
2025-02-06 2024-12-31 13F BUILDERS FIRSTSOURCE COM 12008R107 5,393 -1,650 -23.43 771 -43.59 0.0026
2024-11-19 2024-09-30 13F/A-1 BUILDERS FIRSTSOURCE COM 12008R107 7,043 1,032 17.17 1,366 64.26 0.0045
2024-11-15 2024-09-30 13F BUILDERS FIRSTSOURCE COM 12008R107 7,043 1,032 1,366 0.0008
2024-07-31 2024-06-30 13F BUILDERS FIRSTSOURCE COM 12008R107 6,011 -2,636 -30.48 832 -53.91 0.0028
2024-05-07 2024-03-31 13F BUILDERS FIRSTSOURCE COM 12008R107 8,647 -215 -2.43 1,803 21.91 0.0063
2024-02-06 2023-12-31 13F BUILDERS FIRSTSOURCE COM 12008R107 8,862 -1,288 -12.69 1,480 17.10 0.0054
2023-11-02 2023-09-30 13F BUILDERS FIRSTSOURCE COM 12008R107 10,150 -1,047 -9.35 1,264 -17.07 0.0050
2023-08-09 2023-06-30 13F BUILDERS FIRSTSOURCE COM 12008R107 11,197 -1,694 -13.14 1,523 33.13 0.0057
2023-05-11 2023-03-31 13F BUILDERS FIRSTSOURCE COM 12008R107 12,891 -635 -4.69 1,144 30.59 0.0044
2023-02-13 2022-12-31 13F/A-1 BUILDERS FIRSTSOURCE COM 12008R107 13,526 1,253 10.21 877 20.99 0.0035
2023-02-13 2022-12-31 13F BRUNSWICK COM 12008R107 20,563 8,290 1,384 0.0056
2022-11-17 2022-09-30 13F/A-1 BUILDERS FIRSTSOURCE COM 12008R107 12,273 4,370 55.30 724 83.76 0.0032
2022-11-14 2022-09-30 13F BUILDERS FIRSTSOURCE COM 12008R107 12,273 4,370 697 0.0006
2022-08-05 2022-06-30 13F BUILDERS FIRSTSOURCE COM 12008R107 7,903 81 1.04 394 -21.83 0.0019
2022-05-09 2022-03-31 13F BUILDERS FIRSTSOURCE COM 12008R107 7,822 -3,675 -31.96 504 -48.88 0.0022
2022-02-07 2021-12-31 13F BUILDERS FIRSTSOURCE COM 12008R107 11,497 6,138 114.54 986 257.25 0.0041
2021-10-28 2021-09-30 13F BUILDERS FIRSTSOURCE COM 12008R107 5,359 63 1.19 276 22.67 0.0012
2021-08-13 2021-06-30 13F BUILDERS FIRSTSOURCE COM 12008R107 5,296 5,296 225 0.0010
Disclosed Call Options
File
Date
Effective
Date
Form Security Class ID Opt Avg Share
Price
Shares ΔShares
(%)
Value
(x1000)
ΔValue
(%)
Prior Allocation
(%)
Allocation
(%)
ΔAllocation
(%)
Cost Basis
(x1000)
Profit
(x1000)
Return
(%)
2023-08-09 2023-06-30 13F BUILDERS FIRSTSOURCE COM Call 0 -100.00 0 -100.00 n/a n/a n/a
2023-05-11 2023-03-31 13F BUILDERS FIRSTSOURCE COM Call 10 3 n/a n/a n/a
2023-02-13 2022-12-31 13F/A BUILDERS FIRSTSOURCE COM Call 0 -100.00 0 n/a n/a n/a
2023-02-13 2022-12-31 13F BUILDERS FIRSTSOURCE COM Call 0 0 n/a n/a n/a
2022-11-17 2022-09-30 13F/A BUILDERS FIRSTSOURCE COM Call 10 0.00 0 n/a n/a n/a
2022-11-14 2022-09-30 13F BUILDERS FIRSTSOURCE COM Call 10 1 n/a n/a n/a
2022-08-05 2022-06-30 13F BUILDERS FIRSTSOURCE COM Call 10 0.00 0 -100.00 n/a n/a n/a
2022-05-09 2022-03-31 13F BUILDERS FIRSTSOURCE COM Call 10 4 n/a n/a n/a
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.