NB Bancorp, Inc. (NBBK) Institutional Ownership

Ownership Summary

NB Bancorp, Inc. (NASDAQ:NBBK) currently has 155 active institutional owners and shareholders as of today (December 2025), that have filed 13F forms with the Securities Exchange Commission (SEC).

• These investors collectively held 61.5% of the company's total shares outstanding in December 2025, up from 53.7% in September 2025.
• The company experienced a 18.33% quarterly change in institutional shares held, alongside an increase of 34.78% in total owners annually.
• Of these 155 institutional investors, 104 increased their holdings in NB Bancorp, while 36 of them reduced positions, and 15 investors maintained their exposure.
• The total number of shares held by institutions in NB Bancorp increased to 21.99Mn as of December 2025, a net change of up by 3.41Mn shares quarter on quarter, and up 3.79Mn shares year over year.
• With 3.10Mn shares, BlackRock, Inc. commands the largest institutional position in NB Bancorp as of December 31, 2025, equating to 8.69% of the company.
• Among the most significant buyers of NB Bancorp during December 2025 were AltraVue Capital, LLC (693.00K), Tieton Capital Management, LLC (524.93K), VANGUARD GROUP INC (350.90K), DIMENSIONAL FUND ADVISORS LP (288.03K), BlackRock, Inc. (281.64K).
• Leading sellers of NB Bancorp stock in December 2025 included MILLENNIUM MANAGEMENT LLC (488.42K), WELLINGTON MANAGEMENT GROUP LLP (355.75K), UBS Group AG (232.26K), STATE STREET CORP (82.54K), Qube Research & Technologies Ltd (69.52K).
• The top 10 institutional holders of NB Bancorp for the quarter ending December 2025 included BlackRock, Inc. (3.10Mn), Pertento Partners LLP (2.34Mn), VANGUARD GROUP INC (2.30Mn), WELLINGTON MANAGEMENT GROUP LLP (1.47Mn), STATE STREET CORP (1.11Mn), GEODE CAPITAL MANAGEMENT, LLC (966.66K), HOTCHKIS & WILEY CAPITAL MANAGEMENT LLC (701.99K), AltraVue Capital, LLC (693.00K), GOLDMAN SACHS GROUP INC (593.89K), Tieton Capital Management, LLC (524.93K).