Octave Specialty Group, Inc.
MX ˙ BMV ˙ US0231398845
SecurityMX:OSG / Octave Specialty Group, Inc.
InstitutionJacobs Levy Equity Management, Inc
Latest Disclosed Ownership884,272 shares
Latest Disclosed Value $ 4,111,865
Jacobs Levy Equity Management, Inc reports 272.82% increase in ownership of OSG / Octave Specialty Group, Inc.

On May 15, 2026 - Jacobs Levy Equity Management, Inc filed a 13F-HR form disclosing ownership of 884,272 shares of Octave Specialty Group, Inc. (MX:OSG) valued at $4,111,865 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 13, 2026 disclosing 237,185 shares of Octave Specialty Group, Inc.. This represents a change in shares of 272.82% 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)
2026-05-15 2026-03-31 13F OCTAVE SPECIALTY GROUP COM NEW 023139884 884,272 647,087 272.82 4,112 122.82 0.0173
2026-02-13 2025-12-31 13F OCTAVE SPECIALTY GROUP COM NEW 023139884 237,185 237,185 1,845 0.0071
2023-08-14 2023-06-30 13F AMBAC FINL GROUP COM NEW 023139884 0 -275,414 -100.00 0 -100.00
2023-05-15 2023-03-31 13F AMBAC FINL GROUP COM NEW 023139884 275,414 275,414 4,263 0.0261
2017-11-09 2017-06-30 13F/A-1 AMBAC FINL GROUP COM 023139884 0 -127,944 -100.00 0 -100.00
2017-05-12 2017-03-31 13F AMBAC FINL GROUP COM 023139884 127,944 35,210 37.97 2,413 15.62 0.0488
2017-02-14 2016-12-31 13F AMBAC FINL GROUP COM 023139884 92,734 16,880 22.25 2,087 49.61 0.0403
2016-11-14 2016-09-30 13F AMBAC FINL GROUP COM 023139884 75,854 -6,500 -7.89 1,395 2.88 0.0249
2016-08-15 2016-06-30 13F AMBAC FINL GROUP COM 023139884 82,354 -3,200 -3.74 1,356 0.30 0.0281
2016-05-16 2016-03-31 13F AMBAC FINL GROUP COM 023139884 85,554 85,554 0.00 1,352 0.0286
2016-02-16 2015-12-31 13F AMBAC FINL GROUP COM 023139884 0 -22,174 -100.00 0 -100.00
2015-11-16 2015-09-30 13F AMBAC FINL GROUP COM 023139884 22,174 22,174 321 0.0066
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.