Company · Ownership research

NB Bancorp, Inc. NBBK

CIK 0001979330 · CUSIP 63945M107

Insider trading Initial holdings Institutional holders

Quarter-end disclosures, not live holdings.

Several CUSIPs are reported for this company; this page shows CUSIP 63945M107 (NBBK), not CUSIP 63945M957 (NBBK), CUSIP 63945M907 (NBBK), and does not merge CUSIPs.

This page lists the top 20 of 177 rows by value; the complete set is available through the API.

Some filings reported values in thousands; those figures were scaled ×1,000 to dollars.

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	$64.98M 3,084,222 shares	0.00%	-19.55K(-0.60%)Reduced	SEC filing ↗ May 13, 2026	▾
02	Pertento Partners LLP CIK 1894571 · View history	$46.49M 2,206,666 shares	4.93%	-137.11K(-5.80%)Reduced	SEC filing ↗ May 14, 2026	▾
03	VANGUARD CAPITAL MANAGEMENT LLC CIK 2100119 · Amended · View history	$35.90M 1,703,928 shares	0.00%	—	SEC filing ↗ May 15, 2026	▾
04	AltraVue Capital, LLC CIK 1740837 · View history	$27.48M 1,304,080 shares	2.37%	+611.08K(+88.20%)Added	SEC filing ↗ May 13, 2026	▾
05	STATE STREET CORP CIK 93751 · View history	$27.25M 1,293,538 shares	0.00%	+179.16K(+16.10%)Added	SEC filing ↗ May 15, 2026	▾
06	GEODE CAPITAL MANAGEMENT, LLC CIK 1214717 · View history	$23.16M 1,098,930 shares	0.00%	+132.27K(+13.70%)Added	SEC filing ↗ May 15, 2026	▾
07	WELLINGTON MANAGEMENT GROUP LLP CIK 902219 · View history	$14.96M 710,000 shares	0.00%	-761.19K(-51.70%)Reduced	SEC filing ↗ May 15, 2026	▾
08	GOLDMAN SACHS GROUP INC CIK 886982 · View history	$14.57M 691,668 shares	0.00%	+97.78K(+16.50%)Added	SEC filing ↗ May 15, 2026	▾
09	Tieton Capital Management, LLC CIK 1381954 · View history	$11.66M 553,570 shares	3.91%	+28.64K(+5.50%)Added	SEC filing ↗ May 8, 2026	▾
10	DIMENSIONAL FUND ADVISORS LP CIK 354204 · View history	$11.01M 522,384 shares	0.00%	+234.36K(+81.40%)Added	SEC filing ↗ May 7, 2026	▾
11	Nuveen, LLC CIK 1871926 · View history	$10.28M 488,033 shares	0.00%	+141.25K(+40.70%)Added	SEC filing ↗ Apr 30, 2026	▾
12	HOTCHKIS & WILEY CAPITAL MANAGEMENT LLC CIK 1164833 · View history	$9.50M 450,772 shares	0.03%	-251.22K(-35.80%)Reduced	SEC filing ↗ May 15, 2026	▾
13	FMR LLC CIK 315066 · View history	$9.22M 437,725 shares	0.00%	+54.51K(+14.20%)Added	SEC filing ↗ May 15, 2026	▾
14	VANGUARD PORTFOLIO MANAGEMENT LLC CIK 2100121 · Amended · View history	$8.14M 386,132 shares	0.00%	—	SEC filing ↗ May 8, 2026	▾
15	TWO SIGMA INVESTMENTS, LP CIK 1179392 · View history	$7.83M 371,807 shares	0.01%	+118.96K(+47.00%)Added	SEC filing ↗ May 15, 2026	▾
16	NORTHERN TRUST CORP CIK 73124 · View history	$7.07M 335,360 shares	0.00%	+11.05K(+3.40%)Added	SEC filing ↗ May 14, 2026	▾
17	CHARLES SCHWAB INVESTMENT MANAGEMENT INC CIK 884546 · View history	$6.71M 318,365 shares	0.00%	-11.03K(-3.30%)Reduced	SEC filing ↗ May 15, 2026	▾
18	SEI INVESTMENTS CO CIK 350894 · View history	$6.37M 302,181 shares	0.01%	+158.40K(+110.20%)Added	SEC filing ↗ May 13, 2026	▾
19	MORGAN STANLEY CIK 895421 · View history	$5.90M 279,870 shares	0.00%	+37.74K(+15.60%)Added	SEC filing ↗ May 15, 2026	▾
20	Legato Capital Management LLC CIK 1442641 · View history	$5.82M 276,070 shares	0.53%	+104.71K(+61.10%)Added	SEC filing ↗ May 14, 2026	▾

Showing 20 / 177 institutions. The complete set is available through the API.

Coverage & totals by quarter

Reporting institutions

177

Cancelled or null records excluded

Disclosed shares

23,086,628

Not deduplicated across managers

Disclosed value

$486.31M

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.

NB Bancorp, Inc. · Q1 2026

Explore all 177 reporting institutions.

This page includes 20 of 177 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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Sources, coverage & how to read this data

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.