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 164 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	$61.52M 3,103,770 shares	0.00%	+281.64K(+10.00%)Added	SEC filing ↗ Feb 12, 2026	▾
02	Pertento Partners LLP CIK 1894571 · View history	$46.45M 2,343,776 shares	5.10%	+229.44K(+10.90%)Added	SEC filing ↗ Feb 17, 2026	▾
03	VANGUARD GROUP INC CIK 102909 · View history	$45.61M 2,301,034 shares	0.00%	+350.90K(+18.00%)Added	SEC filing ↗ Jan 29, 2026	▾
04	WELLINGTON MANAGEMENT GROUP LLP CIK 902219 · View history	$29.16M 1,471,189 shares	0.01%	-355.75K(-19.50%)Reduced	SEC filing ↗ Feb 17, 2026	▾
05	STATE STREET CORP CIK 93751 · View history	$22.09M 1,114,379 shares	0.00%	-82.54K(-6.90%)Reduced	SEC filing ↗ Feb 13, 2026	▾
06	GEODE CAPITAL MANAGEMENT, LLC CIK 1214717 · View history	$19.16M 966,662 shares	0.00%	+90.01K(+10.30%)Added	SEC filing ↗ Feb 9, 2026	▾
07	HOTCHKIS & WILEY CAPITAL MANAGEMENT LLC CIK 1164833 · View history	$13.91M 701,992 shares	0.04%	+7.01K(+1.00%)Added	SEC filing ↗ Feb 17, 2026	▾
08	AltraVue Capital, LLC CIK 1740837 · View history	$13.74M 693,000 shares	1.13%	+693.00KNew	SEC filing ↗ Feb 11, 2026	▾
09	GOLDMAN SACHS GROUP INC CIK 886982 · Amended · View history	$11.77M 593,888 shares	0.00%	+68.99K(+13.10%)Added	SEC filing ↗ Mar 25, 2026	▾
10	Tieton Capital Management, LLC CIK 1381954 · View history	$10.40M 524,935 shares	3.56%	+524.93KNew	SEC filing ↗ Feb 10, 2026	▾
11	FMR LLC CIK 315066 · View history	$7.60M 383,212 shares	0.00%	+58.53K(+18.00%)Added	SEC filing ↗ Feb 17, 2026	▾
12	Nuveen, LLC CIK 1871926 · View history	$6.87M 346,779 shares	0.00%	+238.03K(+218.90%)Added	SEC filing ↗ Feb 12, 2026	▾
13	CHARLES SCHWAB INVESTMENT MANAGEMENT INC CIK 884546 · View history	$6.53M 329,398 shares	0.00%	+41.94K(+14.60%)Added	SEC filing ↗ Feb 13, 2026	▾
14	NORTHERN TRUST CORP CIK 73124 · View history	$6.43M 324,313 shares	0.00%	+14.61K(+4.70%)Added	SEC filing ↗ Feb 17, 2026	▾
15	DIMENSIONAL FUND ADVISORS LP CIK 354204 · View history	$5.71M 288,028 shares	0.00%	+288.03KNew	SEC filing ↗ Feb 12, 2026	▾
16	ALLIANCEBERNSTEIN L.P. CIK 1109448 · View history	$5.04M 254,219 shares	0.00%	+213.49K(+524.20%)Added	SEC filing ↗ Feb 17, 2026	▾
17	TWO SIGMA INVESTMENTS, LP CIK 1179392 · View history	$5.01M 252,845 shares	0.01%	+46.98K(+22.80%)Added	SEC filing ↗ Feb 17, 2026	▾
18	MARSHALL WACE, LLP CIK 1318757 · View history	$4.98M 251,512 shares	0.00%	-25.59K(-9.20%)Reduced	SEC filing ↗ Feb 13, 2026	▾
19	RENAISSANCE TECHNOLOGIES LLC CIK 1037389 · View history	$4.98M 251,274 shares	0.01%	+140.37K(+126.60%)Added	SEC filing ↗ Feb 12, 2026	▾
20	MORGAN STANLEY CIK 895421 · Amended · View history	$4.80M 242,132 shares	0.00%	+120.06K(+98.40%)Added	SEC filing ↗ May 27, 2026	▾

Showing 20 / 164 institutions. The complete set is available through the API.

Coverage & totals by quarter

Reporting institutions

164

Cancelled or null records excluded

Disclosed shares

22,274,768

Not deduplicated across managers

Disclosed value

$441.33M

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. · Q4 2025

Explore all 164 reporting institutions.

This page includes 20 of 164 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.