STOCK TITAN

NB Bancorp (NBBK) CEO adds to stake with open-market share buys

Filing Impact
(Neutral)
Filing Sentiment
(Positive)
Form Type
4

Rhea-AI Filing Summary

NB Bancorp, Inc. President, CEO and Chairman Joseph P. Campanelli reported multiple open-market purchases of the company’s Common Stock on May 15, 2026. He bought a total of 3,000 shares at prices around $19.17–$19.21 per share. After these purchases, he directly owns 375,290 shares of NB Bancorp common stock. He also reports indirect holdings of 3,677 shares through an ESOP, 50,470 shares through a 401(k), 47,000 shares in an IRA, and 3,000 shares as trustee for a trust. Some of the reported direct holdings include restricted stock that vests gradually beginning in 2026 and 2027.

Positive

  • None.

Negative

  • None.
Insider CAMPANELLI JOSEPH P
Role President & CEO
Bought 3,000 shs ($58K)
Type Security Shares Price Value
Purchase Common Stock 500 $19.16 $10K
Purchase Common Stock 133 $19.17 $3K
Purchase Common Stock 400 $19.175 $8K
Purchase Common Stock 100 $19.1796 $2K
Purchase Common Stock 767 $19.18 $15K
Purchase Common Stock 500 $19.19 $10K
Purchase Common Stock 253 $19.20 $5K
Purchase Common Stock 100 $19.205 $2K
Purchase Common Stock 247 $19.21 $5K
holding Common Stock -- -- --
holding Common Stock -- -- --
holding Common Stock -- -- --
holding Common Stock -- -- --
Holdings After Transaction: Common Stock — 375,290 shares (Direct, null); Common Stock — 47,000 shares (Indirect, By IRA)
Footnotes (1)
  1. Includes shares of restricted stock which vest at a rate of 20% per year commencing on April 24, 2026. Includes shares of restricted stock which vest at a rate of 33 1/3% per year commencing on February 25, 2027.
Shares bought 3,000 shares Open-market purchases on May 15, 2026
Example purchase price $19.2100/share Common Stock open-market buy on May 15, 2026
Direct holdings after trades 375,290 shares Common Stock directly owned following May 15, 2026 transactions
ESOP indirect holdings 3,677 shares Common Stock held indirectly via ESOP
401(k) indirect holdings 50,470 shares Common Stock held indirectly via 401(k)
IRA indirect holdings 47,000 shares Common Stock held indirectly via IRA
Trust indirect holdings 3,000 shares Common Stock held as trustee for trust
restricted stock financial
"Includes shares of restricted stock which vest at a rate of 20% per year"
Shares granted to an individual that carry limits on transfer or sale until certain conditions are met, such as staying with the company for a set time or hitting performance targets. Think of them as a locked gift that gradually opens; for investors they matter because they affect how many shares may enter the market later, signal management incentives and potential dilution, and reveal confidence in future company performance.
ESOP financial
"total_shares_following_transaction: 3677.0000, nature_of_ownership: By ESOP"
An Employee Stock Ownership Plan (ESOP) is a program that gives employees ownership shares in their company, often as part of their benefits package. It acts like a company-sponsored savings plan, allowing workers to have a stake in the company's success, which can boost motivation and loyalty. For investors, ESOPs can influence company decisions and stock value, making them an important aspect of corporate ownership and governance.
401(k) financial
"total_shares_following_transaction: 50470.0000, nature_of_ownership: By 401(k)"
A 401(k) is a type of retirement savings plan offered by employers that allows workers to set aside a portion of their paycheck before taxes are taken out. The money saved in a 401(k) can grow over time through investments, helping individuals build funds for their future retirement. It matters to investors because it provides a tax-advantaged way to save and invest for long-term financial security.
IRA financial
"total_shares_following_transaction: 47000.0000, nature_of_ownership: By IRA"
An individual retirement account (IRA) is a savings account designed to help people put aside money for their retirement, often with tax advantages that encourage long-term savings. It matters to investors because it can grow over time, providing financial security later in life, and offers benefits that can reduce current taxes or allow investments to compound more effectively.
open-market purchase financial
"transaction_action: open-market purchase"
An open-market purchase is when an investor or a company buys shares on a public stock exchange at the going market price, rather than through a private deal. It matters to investors because these purchases change how many shares are available, can push the stock price up or signal confidence from large buyers, and often affect per-share metrics like earnings—think of it like someone buying lots of apples off a grocery shelf, reducing supply and potentially raising the price.
SEC Form 4
FORM 4UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934
or Section 30(h) of the Investment Company Act of 1940
OMB APPROVAL
OMB Number:3235-0287
Estimated average burden
hours per response:0.5
Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).
Check this box to indicate that a transaction was made pursuant to a contract, instruction or written plan for the purchase or sale of equity securities of the issuer that is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c). See Instruction 10.
1. Name and Address of Reporting Person*
CAMPANELLI JOSEPH P

(Last)(First)(Middle)
1063 GREAT PLAIN AVE

(Street)
NEEDHAM MASSACHUSETTS 02492

(City)(State)(Zip)

UNITED STATES

(Country)
2. Issuer Name and Ticker or Trading Symbol
NB Bancorp, Inc. [ NBBK ]
5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
XDirector10% Owner
XOfficer (give title below)XOther (specify below)
President & CEOChairman of the Board
2a. Foreign Trading Symbol
3. Date of Earliest Transaction (Month/Day/Year)
05/15/2026
6. Individual or Joint/Group Filing (Check Applicable Line)
XForm filed by One Reporting Person
Form filed by More than One Reporting Person
4. If Amendment, Date of Original Filed (Month/Day/Year)

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1. Title of Security (Instr. 3) 2. Transaction Date (Month/Day/Year)2A. Deemed Execution Date, if any (Month/Day/Year)3. Transaction Code (Instr. 8) 4. Securities Acquired (A) or Disposed Of (D) (Instr. 3, 4 and 5) 5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4) 6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4) 7. Nature of Indirect Beneficial Ownership (Instr. 4)
CodeVAmount(A) or (D)Price
Common Stock05/15/2026P500A$19.16375,290(1)(2)D
Common Stock05/15/2026P133A$19.17375,423(1)(2)D
Common Stock05/15/2026P400A$19.175375,823(1)(2)D
Common Stock05/15/2026P100A$19.1796375,923(1)(2)D
Common Stock05/15/2026P767A$19.18376,690(1)(2)D
Common Stock05/15/2026P500A$19.19377,190(1)(2)D
Common Stock05/15/2026P253A$19.2377,443(1)(2)D
Common Stock05/15/2026P100A$19.205377,543(1)(2)D
Common Stock05/15/2026P247A$19.21377,790(1)(2)D
Common Stock47,000IBy IRA
Common Stock3,000IAs trustee for trust
Common Stock50,470IBy 401(k)
Common Stock3,677IBy ESOP
Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned
(e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 3) 2. Conversion or Exercise Price of Derivative Security 3. Transaction Date (Month/Day/Year)3A. Deemed Execution Date, if any (Month/Day/Year)4. Transaction Code (Instr. 8) 5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5) 6. Date Exercisable and Expiration Date (Month/Day/Year)7. Title and Amount of Securities Underlying Derivative Security (Instr. 3 and 4) 8. Price of Derivative Security (Instr. 5) 9. Number of derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4) 10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4) 11. Nature of Indirect Beneficial Ownership (Instr. 4)
CodeV(A)(D)Date ExercisableExpiration DateTitleAmount or Number of Shares
Explanation of Responses:
1. Includes shares of restricted stock which vest at a rate of 20% per year commencing on April 24, 2026.
2. Includes shares of restricted stock which vest at a rate of 33 1/3% per year commencing on February 25, 2027.
/s/ Steven Lanter, pursuant to power of attorney05/18/2026
** Signature of Reporting PersonDate
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
* If the form is filed by more than one reporting person, see Instruction 4 (b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.
Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB Number.
* Form 4: SEC 1474 (03-26)

FAQ

What insider activity did NB Bancorp (NBBK) report for Joseph P. Campanelli?

NB Bancorp reported that President and CEO Joseph P. Campanelli made multiple open-market purchases totaling 3,000 shares of Common Stock on May 15, 2026. These transactions were executed at prices just above $19 per share.

At what prices did NB Bancorp (NBBK) CEO purchase shares in the latest Form 4?

The CEO’s open-market purchases occurred at prices ranging from $19.1600 to $19.2100 per share. Each trade involved relatively small blocks, reflecting a series of individual executions rather than a single large transaction on May 15, 2026.

How many NB Bancorp (NBBK) shares does the CEO directly hold after these transactions?

Following the reported May 15, 2026 purchases, Joseph P. Campanelli directly holds 375,290 shares of NB Bancorp Common Stock. This direct position includes restricted stock awards that are scheduled to vest over several years beginning in 2026 and 2027.

What indirect NB Bancorp (NBBK) share holdings are reported for the CEO?

The filing shows indirect ownership of 3,677 shares through an ESOP, 50,470 shares via a 401(k), 47,000 shares in an IRA, and 3,000 shares as trustee for a trust. These positions supplement his reported direct holdings of NB Bancorp stock.

Does the NB Bancorp (NBBK) Form 4 mention restricted stock for the CEO?

Yes. Footnotes state that his reported direct holdings include restricted stock that vests 20% per year starting April 24, 2026, and other restricted shares vesting 33 1/3% per year beginning February 25, 2027, providing a scheduled vesting profile.