NB Bancorp
NBBK
163 hedge funds and large institutions have $441M invested in NB Bancorp in 2025 Q4 according to their latest regulatory filings, with 34 funds opening new positions, 78 increasing their positions, 35 reducing their positions, and 14 closing their positions.
949% more call options, than puts
Call options by funds: $5.7M | Put options by funds: $543K
143% more first-time investments, than exits
New positions opened: 34 | Existing positions closed: 14
123% more repeat investments, than reductions
Existing positions increased: 78 | Existing positions reduced: 35
30% more capital invested
Capital invested by funds: $339M → $441M (+$102M)
12% more funds holding
Funds holding: 146 → 163 (+17)
7.71% more ownership
Funds ownership: 48.19% → 55.91% (+7.7%)
Top Buyers
| Rank | Fund | Capital Flow |
|---|---|---|
| 1 |
AC
AltraVue Capital
Bellevue,
Washington
|
+$13.2M |
| 2 |
TCM
Tieton Capital Management
Yakima,
Washington
|
+$9.99M |
| 3 |
Vanguard Group
Malvern,
Pennsylvania
|
+$6.68M |
| 4 |
Dimensional Fund Advisors
Austin,
Texas
|
+$5.48M |
| 5 |
BlackRock
New York
|
+$5.36M |
Top Sellers
| Rank | Fund | Capital Flow |
|---|---|---|
| 1 |
Millennium Management
New York
|
-$9.29M |
| 2 |
Wellington Management Group
Boston,
Massachusetts
|
-$6.77M |
| 3 |
UBS Group
Zurich,
Switzerland
|
-$4.42M |
| 4 |
PP
Prospector Partners
Guilford,
Connecticut
|
-$2.66M |
| 5 |
State Street
Boston,
Massachusetts
|
-$1.57M |
NBBK Hedge Fund Activity: Q4 2025 in Review
163 of the 8,267 institutional investors tracked by Wall St. Rank reported a position in NB Bancorp (NBBK) for Q4 2025, worth a combined $441M — up 30% from $339M a quarter earlier.
Buyers outnumbered sellers: 34 funds opened new NBBK positions and 14 closed out — a net gain of 20 holders — while 78 added to existing stakes and 35 trimmed.
The largest buyer was AltraVue Capital, opening a new position worth an estimated $13.2M. The largest seller was Millennium Management, cutting an estimated $9.29M.
- 163 institutional investors held NB Bancorp (NBBK) as of Q4 2025, up from 146 in Q3 2025.
- Funds reported $441M of NB Bancorp stock for Q4 2025, up 30% quarter-over-quarter.
- 34 funds opened new NB Bancorp positions in Q4 2025 and 14 closed out, a net change of +20 holders.
- The largest NB Bancorp buyer in Q4 2025 was AltraVue Capital, an estimated $13.2M added.
- The largest NB Bancorp seller in Q4 2025 was Millennium Management, an estimated $9.29M sold.
Based on aggregated 13F filings for Q4 2025.