NB Bancorp, Inc. (NBBK) Institutional Ownership

Ownership Summary

NB Bancorp, Inc. (NASDAQ:NBBK) currently has 39 active institutional owners and shareholders as of today (December 2025), that have filed 13F forms with the Securities Exchange Commission (SEC).

• The percentage of NB Bancorp owned by institutions changed from 51.1% in September 2025 to 8.7% in December 2025, marking a slight down trend.
• On a quarter-over-quarter basis, institutional holdings shifted by 7.03%, with a year-over-year a decrease of 66.09% in the count of filers.
• Of these 39 institutional investors, 21 increased their holdings in NB Bancorp, while 8 of them reduced positions, and 10 investors maintained their exposure.
• The total number of shares held by institutions in NB Bancorp increased to 3.26Mn as of December 2025, a net change of up by 213.87K shares quarter on quarter, and down 14.95Mn shares year over year.
• As of December 31, 2025, VANGUARD GROUP INC held NB Bancorp's largest shareholding position with over 2.30Mn shares, representing 6.13% of total outstanding shares.
• Among the most significant buyers of NB Bancorp during December 2025 were VANGUARD GROUP INC (350.90K), Four Tree Island Advisory LLC (21.46K), PRINCIPAL FINANCIAL GROUP INC (20.38K), NewEdge Wealth, LLC (18.42K), Round Rock Advisors LLC (17.94K).
• Leading sellers of NB Bancorp stock in December 2025 included UBS Group AG (232.26K), GREAT OAK CAPITAL PARTNERS, LLC (20.29K), Stilwell Value LLC (15.00K), FLAGSHIP HARBOR ADVISORS, LLC (5.48K), HENNESSY ADVISORS INC (4.00K).
• The top 10 institutional holders of NB Bancorp for the quarter ending December 2025 included VANGUARD GROUP INC (2.30Mn), HENNESSY ADVISORS INC (181.00K), UBS Group AG (146.09K), INTERNATIONAL ASSETS INVESTMENT MANAGEMENT, LLC (86.90K), Stilwell Value LLC (65.00K), PRINCIPAL FINANCIAL GROUP INC (64.47K), LYNCH & ASSOCIATES/IN (54.33K), Round Rock Advisors LLC (51.91K), NORTHEAST INVESTMENT MANAGEMENT (23.00K), Modera Wealth Management, LLC (22.01K).