Ranked by reported Q2 2026 13F market value
Share of total reported institutional value in OSG held by the largest 10 / 25 filers.
| # | Institution | Shares Held | Market Value | QoQ Change | Ownership % | % of Fund |
|---|---|---|---|---|---|---|
| 1 | BlackRock, Inc. | 4.6M | $28.5M | +16.7% | 10.150% | 0.00% |
| 2 | Western Standard LLC | 2.2M | $14.0M | 0.0% | 4.989% | 4.75% |
| 3 | VANGUARD CAPITAL MANAGEMENT LLC | 2.0M | $12.3M | +1.4% | 4.379% | 0.00% |
| 4 | PRESCOTT GROUP CAPITAL MANAGEMENT, L.L.C. | 1.6M | $10.3M | +3.5% | 3.658% | 0.89% |
| 5 | THIRD AVENUE MANAGEMENT LLC | 1.3M | $8.4M | +0.1% | 2.979% | 1.34% |
| 6 | Bain Capital Credit, LP | 1.1M | $6.9M | 0.0% | 2.459% | 1.88% |
| 7 | GEODE CAPITAL MANAGEMENT, LLC | 1.1M | $6.9M | +8.2% | 2.456% | 0.00% |
| 8 | SUSQUEHANNA INTERNATIONAL GROUP, LLP | 1.1M | $6.8M | +36.9% | 2.411% | 0.00% |
| 9 | Caption Management, LLC | 901K | $5.6M | -12.3% | 2.001% | 0.03% |
| 10 | STATE STREET CORP | 899K | $5.6M | -4.5% | 1.995% | 0.00% |
| 11 | DIMENSIONAL FUND ADVISORS LP | 717K | $4.5M | -45.3% | 1.591% | 0.00% |
| 12 | JACOBS LEVY EQUITY MANAGEMENT, INC | 650K | $4.1M | -26.6% | 1.442% | 0.01% |
| 13 | MARSHALL WACE, LLP | 602K | $3.8M | -43.5% | 1.336% | 0.00% |
| 14 | ZACKS INVESTMENT MANAGEMENT | 590K | $3.7M | β | 1.310% | 0.03% |
| 15 | Bracebridge Capital, LLC | 579K | $3.6M | 0.0% | 1.286% | 0.07% |
| 16 | MORGAN STANLEY | 570K | $3.6M | +142.1% | 1.264% | 0.00% |
| 17 | GOLDMAN SACHS GROUP INC | 561K | $3.5M | +61.9% | 1.245% | 0.00% |
| 18 | RIHO Partners, LLC | 555K | $3.5M | +1.5% | 1.232% | 1.95% |
| 19 | ESSEX INVESTMENT MANAGEMENT CO LLC | 539K | $3.4M | +28.9% | 1.197% | 0.44% |
| 20 | CITADEL ADVISORS LLC | 530K | $3.3M | -1.9% | 1.177% | 0.00% |
| 21 | GENDELL JEFFREY L | 494K | $3.1M | -65.0% | 1.097% | 0.03% |
| 22 | Wolf Hill Capital Management, LP | 480K | $3.0M | -67.3% | 1.066% | 0.25% |
| 23 | Nuveen, LLC | 428K | $2.7M | -46.5% | 0.950% | 0.00% |
| 24 | VANGUARD PORTFOLIO MANAGEMENT LLC | 392K | $2.4M | +32.6% | 0.871% | 0.00% |
| 25 | CHARLES SCHWAB INVESTMENT MANAGEMENT INC | 378K | $2.4M | +27.9% | 0.839% | 0.00% |
denotes a marquee investor (Buffett, Burry, ARK, Tiger Global, Pershing Square, Baupost and other widely-followed managers). β% of Fundβ shows how much of that investorβs total 13F portfolio is invested in OSG β a direct measure of their conviction.
Filings activity in OSG during Q2 2026, grouped by how each filer changed its position.
Institutions that opened a new OSG position in Q2 2026
Institutions that fully closed their OSG position in Q2 2026
8 quarters of 13F filings Β· Ξ columns show change vs prior quarter
| Quarter | Inst. Holders | Ξ Holders | Ownership % | Ξ Ownership | Total 13F Value | Ξ Value |
|---|---|---|---|---|---|---|
| Q2 2026 | 148 | +1.4% | β | β | $196M | +27% |
| Q1 2026 | 146 | +0.0% | β | β | $155M | 48% |
| Q4 2025 | 146 | +14% | β | β | $299M | 49% |
| Q3 2025 | 128 | 12% | β | β | $584M | +86% |
| Q2 2025 | 145 | 15% | β | β | $313M | 13% |
| Q1 2025 | 171 | 5.0% | β | β | $361M | 86% |
| Q4 2024 | 180 | +2.3% | β | β | $2.56B | +468% |
| Q3 2024 | 176 | β | β | β | $450M | β |
Source: SEC 13F institutional filings. Ownership % requires market cap data and will show once linked. Ξ columns compare to the immediately prior filed quarter.
Quick answers to the most common questions about buying OSG stock.
Based on Q2 2026 13F filings, institutional ownership of Octave Specialty Group, Inc. stands at not currently reported, held across 148 reporting institutions.
BlackRock, Inc. is the largest reported institutional holder of OSG, with approximately 4,572,516 shares worth $0.03B as of Q2 2026.
Yes β 2 widely-followed marquee investors appear among the top 25 institutional holders of OSG, including SUSQUEHANNA INTERNATIONAL GROUP, LLP, CITADEL ADVISORS LLC.
Our composite Smart Money Score for OSG is 56 out of 100 (Neutral). It combines net institutional buying activity, ownership shift, marquee investor presence, and holder-count growth.
37 institutions opened new positions in OSG during Q2 2026, while 34 fully exited. 79 added to existing positions and 28 trimmed.
Quarter-over-quarter ownership change for OSG is not yet available β at least two quarters of 13F data are required.
The top 10 institutions account for 53.7% of all reported 13F value in OSG, and the top 25 account for 79.3%.
All data is sourced from SEC Form 13F filings, which institutional investment managers with at least $100M in assets are required to file each quarter. We process every 13F filing from EDGAR and recompute the aggregates after each cycle. Insider transactions are sourced from Form 4 filings.
Octave Specialty Group, Inc. (OSG) Institutional Ownership