MasterBrand, Inc.
US ˙ NYSE

SecurityMBC / MasterBrand, Inc.
InstitutionSei Investments Co
Latest Disclosed Ownership314,603 shares
Latest Disclosed Value $ 3,473,219
Sei Investments Co reports 35.76% increase in ownership of MBC / MasterBrand, Inc.

On February 13, 2026 - Sei Investments Co filed a 13F-HR form disclosing ownership of 314,603 shares of MasterBrand, Inc. (US:MBC) valued at $3,473,217 USD as of December 31, 2025. The entity filed a previous 13F-HR on November 13, 2025 disclosing 231,742 shares of MasterBrand, Inc.. This represents a change in shares of 35.76% during the quarter. The current value of the position is $2,617,497 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)
2026-02-13 2025-12-31 13F MASTERBRAND COMMON STOCK 57638P104 314,603 82,861 35.76 3,473 13.79 0.0034
2025-11-13 2025-09-30 13F MASTERBRAND COMMON STOCK 57638P104 231,742 196,229 552.56 3,052 686.60 0.0033
2025-08-14 2025-06-30 13F MASTERBRAND COMMON STOCK 57638P104 35,513 -4,475 -11.19 388 -25.67 0.0004
2025-05-14 2025-03-31 13F/A-1 MASTERBRAND COMMON STOCK 57638P104 39,988 6,054 17.84 522 5.45 0.0007
2025-05-13 2025-03-31 13F MASTERBRAND COMMON STOCK 57638P104 33,895 -39 489 0.0005
2025-02-11 2024-12-31 13F MASTERBRAND COMMON STOCK 57638P104 33,934 -2,688 -7.34 496 -26.99 0.0006
2024-11-12 2024-09-30 13F MASTERBRAND COMMON STOCK 57638P104 36,622 -54,816 -59.95 679 -49.48 0.0009
2024-08-13 2024-06-30 13F MASTERBRAND COMMON STOCK 57638P104 91,438 57,143 166.62 1,342 109.03 0.0019
2024-05-07 2024-03-31 13F MASTERBRAND COMMON STOCK 57638P104 34,295 34,295 643 0.0009
2024-02-14 2023-12-31 13F MASTERBRAND COMMON STOCK 57638P104 0 -31,850 -100.00 0 -100.00
2023-11-14 2023-09-30 13F MASTERBRAND COMMON STOCK 57638P104 31,850 -11,341 -26.26 387 -22.91 0.0007
2023-08-11 2023-06-30 13F MASTERBRAND COMMON STOCK 57638P104 43,191 -4,081 -8.63 502 32.45 0.0009
2023-05-12 2023-03-31 13F MASTERBRAND COMMON STOCK 57638P104 47,272 -14,699 -23.72 380 -19.02 0.0007
2023-02-10 2022-12-31 13F MASTERBRAND COMMON STOCK 57638P104 61,971 61,971 468 0.0010
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.