Company · Ownership research

MasterBrand, Inc. MBC

CIK 0001941365 · CUSIP 57638P104

Insider trading Initial holdings Institutional holders

Quarter-end disclosures, not live holdings.

Several CUSIPs are reported for this company; this page shows CUSIP 57638P104 (MBC), not CUSIP 57638P904 (MBC), CUSIP 57638P954 (MBC), and does not merge CUSIPs.

This page lists the top 20 of 336 rows by value; the complete set is available through the API.

Top 20 institutions

Weight means this stock's share of the manager's own portfolio.

By reported value

#	Manager	Value	Manager weight	Change vs prior	Source
01	BlackRock, Inc. CIK 2012383 · View history	$160.82M 19,352,651 shares	0.00%	-9.45K(0.00%)Reduced	SEC filing ↗ May 13, 2026	▾
02	Coliseum Capital Management, LLC CIK 1409751 · View history	$105.49M 12,694,710 shares	8.65%	+1.92M(+17.80%)Added	SEC filing ↗ May 15, 2026	▾
03	Gates Capital Management, Inc. CIK 1312908 · View history	$85.98M 10,346,864 shares	2.97%	+1.12M(+12.20%)Added	SEC filing ↗ May 15, 2026	▾
04	DIMENSIONAL FUND ADVISORS LP CIK 354204 · View history	$58.26M 7,010,428 shares	0.01%	+447.35K(+6.80%)Added	SEC filing ↗ May 7, 2026	▾
05	Boston Partners CIK 1386060 · View history	$55.90M 6,727,552 shares	0.06%	-1.97M(-22.60%)Reduced	SEC filing ↗ May 11, 2026	▾
06	VANGUARD CAPITAL MANAGEMENT LLC CIK 2100119 · Amended · View history	$47.58M 5,725,492 shares	0.00%	—	SEC filing ↗ May 15, 2026	▾
07	Pertento Partners LLP CIK 1894571 · View history	$41.26M 4,964,821 shares	4.38%	+1.08M(+28.00%)Added	SEC filing ↗ May 14, 2026	▾
08	Sixth Street Partners Management Company, L.P. CIK 1812095 · View history	$40.76M 4,905,383 shares	5.74%	0(0.00%)Unchanged	SEC filing ↗ May 15, 2026	▾
09	STATE STREET CORP CIK 93751 · View history	$40.64M 4,891,066 shares	0.00%	-66.11K(-1.30%)Reduced	SEC filing ↗ May 15, 2026	▾
10	FMR LLC CIK 315066 · View history	$36.07M 4,340,250 shares	0.00%	+619.73K(+16.70%)Added	SEC filing ↗ May 15, 2026	▾
11	PZENA INVESTMENT MANAGEMENT LLC CIK 1027796 · View history	$31.69M 3,814,014 shares	0.10%	+28.09K(+0.70%)Added	SEC filing ↗ Apr 24, 2026	▾
12	ACK Asset Management LLC CIK 1510940 · View history	$30.75M 3,700,000 shares	3.84%	+1.40M(+60.90%)Added	SEC filing ↗ May 15, 2026	▾
13	COOKE & BIELER LP CIK 24386 · View history	$29.87M 3,594,545 shares	0.34%	+763.51K(+27.00%)Added	SEC filing ↗ May 4, 2026	▾
14	UBS AM, a distinct business unit of UBS ASSET MANAGEMENT AMERICAS LLC CIK 861177 · View history	$26.05M 3,134,245 shares	0.01%	+9.85K(+0.30%)Added	SEC filing ↗ May 13, 2026	▾
15	GEODE CAPITAL MANAGEMENT, LLC CIK 1214717 · View history	$25.75M 3,098,501 shares	0.00%	+88.07K(+2.90%)Added	SEC filing ↗ May 15, 2026	▾
16	GOLDMAN SACHS GROUP INC CIK 886982 · View history	$25.45M 3,062,879 shares	0.00%	+446.22K(+17.10%)Added	SEC filing ↗ May 15, 2026	▾
17	Apollo Management Holdings, L.P. CIK 1449434 · View history	$21.92M 2,638,219 shares	0.37%	+2.64MNew	SEC filing ↗ May 15, 2026	▾
18	CHARLES SCHWAB INVESTMENT MANAGEMENT INC CIK 884546 · View history	$21.13M 2,542,961 shares	0.00%	+31.11K(+1.20%)Added	SEC filing ↗ May 15, 2026	▾
19	VANGUARD PORTFOLIO MANAGEMENT LLC CIK 2100121 · Amended · View history	$20.42M 2,457,785 shares	0.00%	—	SEC filing ↗ May 8, 2026	▾
20	Monarch Alternative Capital LP CIK 1281084 · View history	$16.62M 2,000,000 shares	2.83%	+2.00MNew	SEC filing ↗ May 15, 2026	▾

Showing 20 / 336 institutions. The complete set is available through the API.

Coverage & totals by quarter

Reporting institutions

336

Cancelled or null records excluded

Disclosed shares

154,912,406

Not deduplicated across managers

Disclosed value

$1.29B

Not market cap or free float

Reporting institutions by quarter

Counts also change with data coverage and reporting entities; they do not measure net buying. Distinct managers with a live stock row in this CUSIP; totals may include overlapping filings and are not a share of the company.

MasterBrand, Inc. · Q1 2026

Explore all 336 reporting institutions.

This page includes 20 of 336 reporting institutions. Log in to look up the full history beyond 3 years, use advanced screening & filtering, download CSV, and get the complete set through the Akkru API.

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Figures are as reported to the SEC and merged with later amendments where Akkru could match them. Preview limits apply to what is listed, not to the totals, which come from the complete reported data. Nothing is zero-filled: a missing quarter or month is shown as missing.