Winchester Bancorp, Inc./MD/ (WSBK) Institutional Ownership

Ownership Summary

According to SEC filings for the period ending September 2025, Winchester Bancorp, Inc./MD/ (NASDAQ:WSBK) is held by 22 institutional firms.

• Winchester Bancorp saw its institutional ownership percentage rose to 8.1% in September 2025 from 6.0% in June 2025.
• The company experienced a 22.47% quarterly change in institutional shares held, alongside an unavailable change in total owners annually.
• During the quarter, 10 institutions bought more Winchester Bancorp shares, 6 sold shares, and 6 of the 22 total investors held their position steady.
• The aggregate institutional position in Winchester Bancorp now stands at 708.26K shares as of September 2025, after investors increased their holdings (up by 129.96K shares quarter on quarter which is down N/A shares year over year).
• As of September 30, 2025, MANGROVE PARTNERS IM, LLC held Winchester Bancorp's largest shareholding position with over 186.95K shares, representing 2.14% of total outstanding shares.
• Among the most significant buyers of Winchester Bancorp during September 2025 were Northstar Financial Companies, Inc. (70.00K), CITADEL ADVISORS LLC (26.44K), M3F, Inc. (23.23K), MANGROVE PARTNERS IM, LLC (17.85K), Steward Partners Investment Advisory, LLC (8.25K).
• Leading sellers of Winchester Bancorp stock in September 2025 included BANK OF AMERICA CORP /DE/ (9.99K), UBS Group AG (5.30K), LYNCH & ASSOCIATES/IN (5.00K), MILLENNIUM MANAGEMENT LLC (4.32K), Benin Management CORP (500).
• The top 10 institutional holders of Winchester Bancorp for the quarter ending September 2025 included MANGROVE PARTNERS IM, LLC (186.95K), M3F, Inc. (82.55K), Northstar Financial Companies, Inc. (70.00K), VANGUARD GROUP INC (69.17K), Integrated Wealth Concepts LLC (55.00K), Oppenheimer & Close, LLC (50.00K), CITADEL ADVISORS LLC (26.44K), Stilwell Value LLC (25.00K), GEODE CAPITAL MANAGEMENT, LLC (23.90K), RAYMOND JAMES FINANCIAL INC (20.00K).