Octave Specialty Group, Inc.
MX ˙ BMV ˙ US0231398845
SecurityMX:OSG / Octave Specialty Group, Inc.
InstitutionQuadrant Capital Group Llc
Latest Disclosed Ownership1,572 shares
Latest Disclosed Value $ 7,310
Quadrant Capital Group Llc reports 16.29% decrease in ownership of OSG / Octave Specialty Group, Inc.

On May 13, 2026 - Quadrant Capital Group Llc filed a 13F-HR/A form disclosing ownership of 1,572 shares of Octave Specialty Group, Inc. (MX:OSG) valued at $7,310 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 12, 2026 disclosing 1,878 shares of Octave Specialty Group, Inc.. This represents a change in shares of -16.29% during the quarter.

Institutional Ownership: 13F and NPORT Filings

The Security and Class in the table below are shown exactly as filed by the investor. We do our best to track continuity of investments through acquisitions, and this will be reflected in the table as changes in names. In addition to descriptive data, performance of the investment is shown over time. To calculate quarterly performance, we first calculate cost basis of the shares purchased during the quarter, then use that to calculate gross profit. Quarterly return is Gross Profit / Starting Portfolio value.

Note that cost basis is calculated and stored in thousands, so small quarterly changes in shares frequently result in a cost basis of zero.

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Disclosed Equity Positions (from 13F/NPORT Filings)
File
Date
Effective
Date
Form Security Class ID Avg Price
Paid (Est)
Reported
Shares
ΔShares ΔShares
(%)
Reported
Value
(x1000)
ΔValue
(%)
Alloc
(%)
ΔAlloc ΔAlloc (%) Cost Basis
(x1000)
Unrealized
Gain/Loss
(x1000)
2026-05-13 2026-03-31 13F/A-1 OCTAVE SPECIALTY GROUP COM NEW 023139884 1,572 -306 -16.29 7 -50.00 0.0002
2026-05-11 2026-03-31 13F OCTAVE SPECIALTY GROUP COM NEW 023139884 1,572 -306 49 0.0369
2026-02-12 2025-12-31 13F OCTAVE SPECIALTY GROUP COM NEW 023139884 1,878 -605 -24.37 15 -30.00 0.0004
2025-11-13 2025-09-30 13F AMBAC FINL GROUP COM NEW 023139884 2,483 2,483 21 0.0007
2025-08-13 2025-06-30 13F AMBAC FINL GROUP COM NEW 023139884 0 -46 -100.00 0 0.0000
2025-05-13 2025-03-31 13F AMBAC FINL GROUP COM NEW 023139884 46 -101 -68.71 0 -100.00 0.0000
2025-02-13 2024-12-31 13F AMBAC FINL GROUP COM NEW 023139884 147 46 45.54 2 0.00 0.0001
2024-11-12 2024-09-30 13F AMBAC FINL GROUP COM NEW 023139884 101 -1,439 -93.44 1 -94.74 0.0001
2024-08-12 2024-06-30 13F AMBAC FINL GROUP COM NEW 023139884 1,540 1,347 697.93 20 533.33 0.0015
2024-05-15 2024-03-31 13F AMBAC FINL GROUP COM NEW 023139884 193 -129 -40.06 3 -40.00 0.0002
2024-02-08 2023-12-31 13F AMBAC FINL GROUP COM NEW 023139884 322 44 15.83 5 66.67 0.0005
2023-11-14 2023-09-30 13F AMBAC FINL GROUP COM NEW 023139884 278 143 105.93 3 200.00 0.0003
2023-08-10 2023-06-30 13F AMBAC FINL GROUP COM NEW 023139884 135 0 0.00 2 -50.00 0.0002
2023-05-11 2023-03-31 13F AMBAC FINL GROUP COM NEW 023139884 135 0 0.00 2 0.00 0.0002
2023-02-13 2022-12-31 13F AMBAC FINL GROUP COM NEW 023139884 135 -55 -28.95 2 0.00 0.0003
2022-11-10 2022-09-30 13F AMBAC FINL GROUP COM NEW 023139884 190 0 0.00 2 0.00 0.0003
2022-08-09 2022-06-30 13F AMBAC FINL GROUP COM NEW 023139884 190 121 175.36 2 100.00 0.0003
2022-05-06 2022-03-31 13F AMBAC FINL GROUP COM NEW 023139884 69 -32 -31.68 1 -50.00 0.0001
2022-02-01 2021-12-31 13F AMBAC FINL GROUP COM NEW 023139884 101 0 0.00 2 100.00 0.0002
2021-11-12 2021-09-30 13F AMBAC FINL GROUP COM NEW 023139884 101 101 1 0.0001
2021-02-16 2020-12-31 13F AMBAC FINL GROUP COM NEW 023139884 0 -11 -100.00 0 0.0000
2020-11-13 2020-09-30 13F AMBAC FINL GROUP COM NEW 023139884 11 -73 -86.90 0 -100.00
2020-08-13 2020-06-30 13F AMBAC FINL GROUP COM NEW 023139884 84 84 1 0.0002
2019-07-24 2019-06-30 13F Ambac Financial Group COM 023139884 0 -44 -100.00 0 0.0000
2019-04-29 2019-03-31 13F Ambac Financial Group COM 023139884 44 0 0.00 0 0.0000
2019-01-17 2018-12-31 13F Ambac Financial Group COM 023139884 44 44 0 0.0000
Legend
Shares
The total number of shares held by the institution at the end of the reporting period (the effective date). This is provided in the filing.
Value
The total value of the shares as of the effective date. This is provided in the filing.
Avg. Share Price
The weighted average share price of the shares held by the institution. We use FIFO accounting to determine this price
Class
This is the security class as indicated by the filer. There are a variety of values for this field. Common values include "EC" = equity common, "EP" - equity preferred
Allocation (%)
The percent of the institution's portfolio that this position represents. This is provided in NPORT filings. For 13F filings, we calculate it.
Change in Allocation
The change in allocation from the prior reporting period. This is calculated as current allocation - prior allocation.
Change in Allocation (%)
The percent change in allocation from the prior reporting period. This is calculated as (current allocation - prior allocation) / prior allocation.
Cost Basis
The total cost of the shares held. This is calculated as reported shares * avg. share price
Unrealized Gain/Loss
This is the market value of the position as of the effective date minus the cost basis.