NB Bancorp, Inc. (NBBK) — Institutional Holders, Q2 2026

161 institutional investment managers reported a NBBK position on SEC Form 13F-HR for the quarter ended June 30, 2026, with a combined reported value of $474.7M. Every filer is listed below, ranked by position value, 100 per page; this page shows ranks 1 to 100. Put and call option positions are excluded, and a firm filing several lots or share classes is shown once with its total.

← NBBK stock profile

NBBK in Q2 2026: what funds did

Funds that filed a 13F for both Q1 2026 and Q2 2026, by what they did with the common stock. Share counts are adjusted for any split between the two quarters; dollar figures are the change in shares at this quarter’s price.

New positions

Added to

Trimmed

Sold out

Biggest buyers

AltraVue CapitalAdded · +351,028 sh+$7.4M
BlackRockAdded · +247,322 sh+$5.2M
DIMENSIONAL FUND ADVISORSAdded · +230,936 sh+$4.9M
STATE STREETAdded · +178,228 sh+$3.8M
CITADEL ADVISORSAdded · +173,443 sh+$3.7M

Biggest sellers

Pertento Partners LLPTrimmed · -730,896 sh-$15.4M
WELLINGTON MANAGEMENT GROUP LLPSold out · -710,000 sh-$15.0M
SEI INVESTMENTSTrimmed · -159,835 sh-$3.4M
RENAISSANCE TECHNOLOGIESTrimmed · -132,466 sh-$2.8M
GOLDMAN SACHS GROUPTrimmed · -119,714 sh-$2.5M

NBBK 13F holders ranked 1–100 of 161

Institutional investors reporting a position in NB Bancorp, Inc. on SEC Form 13F-HR for Q2 2026, ranked by reported value.
#	Institution	Shares	Value	% of portfolio	QoQShares vs Q1 2026
1	BlackRock#1 · 3,331,544 sh	3,331,544	$70.4M	<0.01%	+8.0%
2	VANGUARD CAPITAL MANAGEMENT#2 · 1,670,835 sh	1,670,835	$35.3M	<0.01%	-1.9%
3	AltraVue Capital#3 · 1,655,108 sh	1,655,108	$35.0M	2.52%	+26.9%
4	Pertento Partners LLP#4 · 1,475,770 sh	1,475,770	$31.2M	1.68%	-33.1%
5	STATE STREET#5 · 1,471,766 sh	1,471,766	$31.1M	<0.01%	+13.8%
6	GEODE CAPITAL MANAGEMENT#6 · 1,153,217 sh	1,153,217	$24.4M	<0.01%	+4.9%
7	DIMENSIONAL FUND ADVISORS#7 · 753,320 sh	753,320	$15.9M	<0.01%	+44.2%
8	GOLDMAN SACHS GROUP#8 · 571,954 sh	571,954	$12.1M	<0.01%	-17.3%
9	Tieton Capital Management#9 · 546,600 sh	546,600	$11.6M	3.32%	-1.3%
10	HOTCHKIS & WILEY CAPITAL MANAGEMENT#10 · 501,172 sh	501,172	$10.6M	0.03%	+11.2%
11	Nuveen#11 · 498,869 sh	498,869	$10.5M	<0.01%	+2.2%
12	FMR#12 · 497,305 sh	497,305	$10.5M	<0.01%	+13.6%
13	VANGUARD PORTFOLIO MANAGEMENT#13 · 397,046 sh	397,046	$8.4M	<0.01%	+2.8%
14	Legato Capital Management#14 · 366,090 sh	366,090	$7.7M	0.64%	+32.6%
15	NORTHERN#15 · 360,492 sh	360,492	$7.6M	<0.01%	+7.5%
16	NEW YORK STATE COMMON RETIREMENT FUND#16 · 346,155 sh	346,155	$7.3M	<0.01%	+32.8%
17	CHARLES SCHWAB INVESTMENT MANAGEMENT#17 · 318,612 sh	318,612	$6.7M	<0.01%	+0.1%
18	CITADEL ADVISORS#18 · 289,814 sh	289,814	$6.1M	<0.01%	+149.0%
19	TWO SIGMA INVESTMENTS#19 · 277,027 sh	277,027	$5.9M	<0.01%	-25.5%
20	AMERICAN CENTURY COMPANIES#20 · 261,866 sh	261,866	$5.5M	<0.01%	-0.7%
21	VANGUARD FIDUCIARY#21 · 253,951 sh	253,951	$5.4M	<0.01%	0.0%
22	MORGAN STANLEY#22 · 229,194 sh	229,194	$4.8M	<0.01%	-18.1%
23	BRIDGEWAY CAPITAL MANAGEMENT#23 · 221,399 sh	221,399	$4.7M	0.08%	+6.2%
24	Empowered Funds#24 · 181,399 sh	181,399	$3.8M	0.02%	+7.7%
25	HENNESSY ADVISORS#25 · 178,000 sh	178,000	$3.8M	0.12%	-1.1%
26	Bank of New York Mellon#26 · 171,541 sh	171,541	$3.6M	<0.01%	+15.9%
27	D. E. Shaw#27 · 149,931 sh	149,931	$3.2M	<0.01%	+113.0%
28	SEI INVESTMENTS#28 · 142,346 sh	142,346	$3.0M	<0.01%	-52.9%
29	FIRST ADVISORS#29 · 142,253 sh	142,253	$3.0M	<0.01%	+1.4%
30	UBS Group AG#30 · 140,405 sh	140,405	$3.0M	<0.01%	+84.5%
31	INTERNATIONAL ASSETS INVESTMENT MANAGEMENT#31 · 131,013 sh	131,013	$2.8M	0.17%	0.0%
32	RENAISSANCE TECHNOLOGIES#32 · 131,440 sh	131,440	$2.8M	<0.01%	-50.2%
33	ALLIANCEBERNSTEIN L.P.#33 · 130,219 sh	130,219	$2.7M	<0.01%	0.0%
34	PANAGORA ASSET MANAGEMENT#34 · 129,355 sh	129,355	$2.7M	<0.01%	-13.8%
35	Qube Research & Technologies Ltd#35 · 127,236 sh	127,236	$2.7M	<0.01%	-27.3%
36	Financial Engines Advisors L.L.C.#36 · 126,788 sh	126,788	$2.7M	<0.01%	+0.8%
37	MARSHALL WACE, LLP#37 · 123,112 sh	123,112	$2.6M	<0.01%	New
38	AQR CAPITAL MANAGEMENT#38 · 116,349 sh	116,349	$2.5M	<0.01%	-9.7%
39	MANGROVE PARTNERS IM#39 · 111,356 sh	111,356	$2.4M	0.15%	0.0%
40	Invesco Ltd.#40 · 97,941 sh	97,941	$2.1M	<0.01%	-3.3%
41	Oppenheimer & Close#41 · 82,999 sh	82,999	$1.8M	1.11%	0.0%
42	MILLENNIUM MANAGEMENT#42 · 81,447 sh	81,447	$1.7M	<0.01%	-48.5%
43	Integrated Wealth Concepts#43 · 78,691 sh	78,691	$1.7M	<0.01%	+64.2%
44	Swiss National Bank#44 · 77,100 sh	77,100	$1.6M	<0.01%	0.0%
45	CREDIT AGRICOLE S A#45 · 70,000 sh	70,000	$1.5M	<0.01%	0.0%
46	MACKENZIE FINANCIAL#46 · 67,441 sh	67,441	$1.4M	<0.01%	+32.5%
47	Creative Planning#47 · 67,320 sh	67,320	$1.4M	<0.01%	-5.1%
48	Round Rock Advisors#48 · 66,530 sh	66,530	$1.4M	0.18%	+0.1%
49	Focus Partners Wealth#49 · 65,728 sh	65,728	$1.4M	<0.01%	-29.2%
50	BNP PARIBAS FINANCIAL MARKETS#50 · 62,478 sh	62,478	$1.3M	<0.01%	+17.9%
51	PRINCIPAL FINANCIAL GROUP#51 · 59,231 sh	59,231	$1.3M	<0.01%	+7.0%
52	Legal & General Group Plc#52 · 56,718 sh	56,718	$1.2M	<0.01%	+7.0%
53	Y-Intercept (Hong Kong) Ltd#53 · 54,541 sh	54,541	$1.2M	—	New
54	RHUMBLINE ADVISERS#54 · 52,690 sh	52,690	$1.1M	<0.01%	-0.9%
55	LYNCH & ASSOCIATES#55 · 50,334 sh	50,334	$1.1M	—	-5.6%
56	Stilwell Value#56 · 50,000 sh	50,000	$1.1M	0.61%	-23.1%
57	BANK OF AMERICA#57 · 48,905 sh	48,905	$1.0M	<0.01%	-58.8%
58	NIXON PEABODY#58 · 48,516 sh	48,516	$1.0M	—	0.0%
59	AMERIPRISE FINANCIAL#59 · 46,899 sh	46,899	$991.0K	<0.01%	+11.8%
60	CITIGROUP#60 · 46,580 sh	46,580	$984.2K	<0.01%	+39.2%
61	Trexquant Investment#61 · 46,312 sh	46,312	$978.6K	<0.01%	New
62	PRICE T ROWE ASSOCIATES#62 · 46,016 sh	46,016	$973.0K	<0.01%	+12.0%
63	FEDERATED HERMES#63 · 44,967 sh	44,967	$950.2K	<0.01%	+32.6%
64	Quantinno Capital Management#64 · 44,137 sh	44,137	$932.6K	<0.01%	+70.1%
65	WEDGE CAPITAL MANAGEMENT L L P#65 · 43,216 sh	43,216	$913.2K	—	+2.0%
66	Mariner#66 · 42,471 sh	42,471	$897.4K	<0.01%	-14.2%
67	XTX Topco Ltd#67 · 41,912 sh	41,912	$885.6K	0.01%	+5.4%
68	DEUTSCHE BANK AG\#68 · 41,024 sh	41,024	$866.8K	<0.01%	+31.9%
69	EJF Capital#69 · 40,751 sh	40,751	$861.1K	0.58%	-1.7%
70	UBS AM, a distinct business unit of UBS ASSET MANAGEMENT AME#70 · 38,359 sh	38,359	$810.5K	<0.01%	-2.5%
71	Aviance Capital Partners#71 · 38,173 sh	38,173	$806.6K	0.08%	+2.7%
72	STATE OF WISCONSIN INVESTMENT BOARD#72 · 38,169 sh	38,169	$806.5K	<0.01%	+56.5%
73	ARROWSTREET CAPITAL, LIMITED PARTNERSHIP#73 · 35,981 sh	35,981	$760.3K	<0.01%	-10.7%
74	WELLS FARGO & COMPANY#74 · 35,185 sh	35,185	$743.5K	<0.01%	+117.8%
75	Bleakley Financial Group#75 · 34,272 sh	34,272	$724.2K	<0.01%	+152.7%
76	RAFFLES ASSOCIATES#76 · 31,874 sh	31,874	$673.5K	0.61%	+114.3%
77	Allspring Global Investments#77 · 30,429 sh	30,429	$657.9K	<0.01%	+3.2%
78	RAYMOND JAMES FINANCIAL#78 · 29,914 sh	29,914	$632.1K	<0.01%	+200.7%
79	FRANKLIN RESOURCES#79 · 28,370 sh	28,370	$599.5K	<0.01%	+4.0%
80	LPL Financial#80 · 26,409 sh	26,409	$558.0K	<0.01%	+0.2%
81	Rafferty Asset Management#81 · 25,529 sh	25,529	$539.4K	<0.01%	-14.9%
82	NORTHEAST INVESTMENT MANAGEMENT#82 · 25,000 sh	25,000	$528.3K	0.02%	0.0%
83	Vanguard Global Advisers#83 · 24,444 sh	24,444	$516.5K	<0.01%	+4.0%
84	MetLife Investment Management#84 · 24,072 sh	24,072	$508.6K	<0.01%	+5.6%
85	BARCLAYS PLC#85 · 23,951 sh	23,951	$506.1K	<0.01%	+3.7%
86	VANGUARD ASSET MANAGEMENT, Ltd#86 · 23,484 sh	23,484	$496.2K	<0.01%	0.0%
87	Russell Investments Group, Ltd.#87 · 21,332 sh	21,332	$450.7K	<0.01%	+391.1%
88	MIRABELLA FINANCIAL SERVICES LLP#88 · 20,227 sh	20,227	$427.4K	0.04%	New
89	Investment Advisory Group#89 · 20,000 sh	20,000	$422.6K	0.09%	0.0%
90	WILEY BROS.-AINTREE CAPITAL#90 · 19,730 sh	19,730	$416.9K	<0.01%	0.0%
91	JPMORGAN CHASE#91 · 19,283 sh	19,283	$408.6K	0.00%	-46.6%
92	COMMONWEALTH EQUITY SERVICES#92 · 19,285 sh	19,285	$407.5K	<0.01%	-14.3%
93	MIRAE ASSET GLOBAL ETFS Ltd.#93 · 18,740 sh	18,740	$396.0K	<0.01%	+0.3%
94	Harbor Advisors#94 · 17,500 sh	17,500	$369.8K	0.05%	+75.0%
95	MERCER GLOBAL ADVISORS#95 · 16,992 sh	16,992	$359.0K	<0.01%	+45.2%
96	Zurcher Kantonalbank (Zurich Cantonalbank)#96 · 16,976 sh	16,976	$358.7K	<0.01%	0.0%
97	KESTRA PRIVATE WEALTH SERVICES#97 · 16,766 sh	16,766	$354.3K	<0.01%	-5.4%
98	ROCKLAND#98 · 15,969 sh	15,969	$337.4K	—	0.0%
99	Cerity Partners#99 · 15,558 sh	15,558	$328.7K	<0.01%	-10.5%
100	ExodusPoint Capital Management#100 · 15,487 sh	15,487	$327.2K	<0.01%	+7.3%

Funds that sold out of NBBK in Q2 2026 (26)

Held NBBK at the end of Q1 2026 and filed a Q2 2026 13F without it. Not in the list above, because they no longer hold it. Largest prior position first.

Institutions that held NBBK in Q1 2026 and reported no position in Q2 2026.
Institution	Shares sold	Value in Q1 2026
WELLINGTON MANAGEMENT GROUP LLP710,000 sh	710,000	$15.0M
JANE STREET GROUP60,669 sh	60,669	$1.3M
OP Asset Management Ltd58,392 sh	58,392	$1.2M
LAZARD ASSET MANAGEMENT57,302 sh	57,302	$1.2M
SUSQUEHANNA INTERNATIONAL GROUP, LLP51,593 sh	51,593	$1.1M
Integrated Quantitative Investments37,075 sh	37,075	$781.2K
Connor, Clark & Lunn Investment Management Ltd.32,249 sh	32,249	$679.5K
SUSQUEHANNA FUNDAMENTAL INVESTMENTS27,840 sh	27,840	$586.6K
LOS ANGELES CAPITAL MANAGEMENT25,375 sh	25,375	$534.7K
Four Tree Island Advisory25,011 sh	25,011	$527.0K
MARTINGALE ASSET MANAGEMENT L P23,900 sh	23,900	$503.6K
Polymer Capital Management (US)17,866 sh	17,866	$376.4K
Universal- Beteiligungs- und Servicegesellschaft mbH16,846 sh	16,846	$354.9K
Diversified13,194 sh	13,194	$278.0K
Brevan Howard Capital Management10,703 sh	10,703	$225.5K
Quantbot Technologies10,536 sh	10,536	$222.0K
INTECH INVESTMENT MANAGEMENT9,892 sh	9,892	$208.4K
ACADIAN ASSET MANAGEMENT9,040 sh	9,040	$190.0K
GLOBEFLEX CAPITAL L P6,791 sh	6,791	$143.1K
QUADRANT CAPITAL GROUP114 sh	114	$50.2K
RESOURCES MANAGEMENT /CT1,500 sh	1,500	$32.0K
NORTHWESTERN MUTUAL WEALTH MANAGEMENT232 sh	232	$4.9K
MAI Capital Management105 sh	105	$2.2K
Root Financial Partners59 sh	59	$1.2K
Versant Capital Management15 sh	15	$316.00
Hughes Financial Services1 sh	1	$21.00

Source: Form 13F-HR filings on SEC EDGAR, Q2 2026. Values are as reported by each manager at quarter end. “% of portfolio” is the position’s share of the manager’s total reported 13F value for the same quarter. “New” means the manager filed a 13F for Q1 2026 without this position; a dash means no comparison is available. Where a manager’s own filing is internally inconsistent its value is withheld and it is listed last. 13F data shows reported holdings, not recommendations.