Octave Specialty OSG Institutional Ownership

Updated Oct 11, 2026

Octave Specialty Group Inc (NYSE:OSG) appeared in the 13F filings of 147 institutional investors for the quarter ended June 30, 2026.

• These investors held 66.24% of Octave Specialty's outstanding shares at the end of Q2 2026, down from 71.83% in Q1 2026.
• Total holdings of Octave Specialty shares fell 7.60% from Q1 2026, and the number of holders rose 3.52% from Q2 2025.
• Of these 147 holders, 86 added to their positions, 41 reduced their stakes and 20 left their positions unchanged.
• Altogether, institutional holders owned 30.07Mn OSG shares at the end of Q2 2026, down 2.47Mn from the prior quarter and down 5.32Mn from a year earlier.
• BlackRock, Inc. was the top holder of Octave Specialty as of June 30, 2026, with 4.57Mn shares, or 10.07% of shares outstanding.
• Among holders that already owned Octave Specialty, the biggest buyers in Q2 2026 were BlackRock, Inc. (+654.72K shares), Morgan Stanley (+334.32K shares), Goldman Sachs Group Inc (+214.46K shares), Raymond James Financial Inc (+214.02K shares) and AQR Capital Management LLC (+180.06K shares).
• The biggest cuts to OSG positions during Q2 2026 came from Wolf Hill Capital Management, LP (-990.15K shares), Jeffrey L. Gendell (-919.12K shares), Dimensional Fund Advisors LP (-593.18K shares), Jane Street Group, LLC (-485.65K shares) and Marshall Wace, LLP (-463.54K shares).
• According to Business Quant data, the leading holders of OSG for Q2 2026 were BlackRock, Inc. (4.57Mn shares), Western Standard LLC (2.25Mn shares), Vanguard Capital Management LLC (1.97Mn shares), Prescott Group Capital Management, L.L.C. (1.65Mn shares), Third Avenue Management LLC (1.34Mn shares), Bain Capital Credit, LP (1.11Mn shares), Geode Capital Management, LLC (1.11Mn shares), State Street Corp (898.67K shares), Dimensional Fund Advisors LP (716.95K shares) and Jacobs Levy Equity Management, Inc (649.53K shares).