Octave Specialty Group, Inc.
US ˙ NYSE ˙ US0231398845
DIESES SYMBOL IST NICHT MEHR AKTIV

SecurityAMBC / Octave Specialty Group, Inc.
InstitutionState Street Corp
Latest Disclosed Ownership941,404 shares
Latest Disclosed Value $ 4,377,529
State Street Corp reports 0.21% decrease in ownership of AMBC / Octave Specialty Group, Inc.

On May 15, 2026 - State Street Corp filed a 13F-HR form disclosing ownership of 941,404 shares of Octave Specialty Group, Inc. (US:AMBC) valued at $4,377,529 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 13, 2026 disclosing 943,368 shares of Octave Specialty Group, Inc.. This represents a change in shares of -0.21% during the quarter. The current value of the position is $8,500,878 USD.

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 941,404 -1,964 -0.21 4,378 -40.36 0.0002
2026-02-13 2025-12-31 13F OCTAVE SPECIALTY GROUP COM NEW 023139884 943,368 -23,820 -2.46 7,339 -9.01 0.0002
2025-11-14 2025-09-30 13F AMBAC FINL GROUP COM NEW 023139884 967,188 8,333 0.87 8,066 18.50 0.0003
2025-08-14 2025-06-30 13F AMBAC FINL GROUP COM NEW 023139884 958,855 -73,439 -7.11 6,808 -24.63 0.0003
2025-05-15 2025-03-31 13F AMBAC FINL GROUP COM NEW 023139884 1,032,294 -761,748 -42.46 9,033 -60.20 0.0004
2025-02-14 2024-12-31 13F AMBAC FINL GROUP COM NEW 023139884 1,794,042 140,498 8.50 22,695 22.43 0.0009
2024-11-14 2024-09-30 13F AMBAC FINL GROUP COM NEW 023139884 1,653,544 42,504 2.64 18,536 -10.25 0.0008
2024-08-14 2024-06-30 13F AMBAC FINL GROUP COM NEW 023139884 1,611,040 -35,795 -2.17 20,654 -19.76 0.0009
2024-05-15 2024-03-31 13F AMBAC FINL GROUP COM NEW 023139884 1,646,835 20,708 1.27 25,740 -3.95 0.0012
2024-02-14 2023-12-31 13F AMBAC FINL GROUP COM NEW 023139884 1,626,127 16,554 1.03 26,799 38.06 0.0013
2023-11-14 2023-09-30 13F AMBAC FINL GROUP COM NEW 023139884 1,609,573 75,328 4.91 19,411 -11.15 0.0011
2023-08-14 2023-06-30 13F AMBAC FINL GROUP COM NEW 023139884 1,534,245 -220,627 -12.57 21,848 -19.58 0.0011
2023-05-15 2023-03-31 13F AMBAC FINL GROUP COM NEW 023139884 1,754,872 87,376 5.24 27,165 -6.59 0.0015
2023-05-15 2022-12-31 13F/A-99 AMBAC FINL GROUP COM NEW 023139884 1,667,496 48,508 3.00 29,081 40.88 0.0017
2023-05-15 2022-12-31 13F AMBAC FINL GROUP COM NEW 023139884 1,667,496 48,508 29,081 0.0017
2022-11-15 2022-09-30 13F AMBAC FINL GROUP COM NEW 023139884 1,618,988 -22,129 -1.35 20,642 10.82 0.0013
2022-08-15 2022-06-30 13F AMBAC FINL GROUP COM NEW 023139884 1,641,117 21,426 1.32 18,627 10.58 0.0011
2022-05-16 2022-03-31 13F AMBAC FINL GROUP COM NEW 023139884 1,619,691 42,833 2.72 16,845 -33.44 0.0008
2022-02-14 2021-12-31 13F AMBAC FINL GROUP COM NEW 023139884 1,576,858 91,066 6.13 25,309 18.95 0.0012
2021-11-15 2021-09-30 13F AMBAC FINL GROUP COM NEW 023139884 1,485,792 7,682 0.52 21,277 -8.08 0.0011
2021-08-16 2021-06-30 13F AMBAC FINL GROUP COM NEW 023139884 1,478,110 47,472 3.32 23,147 -3.35 0.0012
2021-07-09 2021-03-31 13F/A-1 AMBAC FINL GROUP COM NEW 023139884 1,430,638 21,777 1.55 23,949 10.53 0.0014
2021-05-17 2021-03-31 13F AMBAC FINL GROUP COM NEW 023139884 1,430,638 21,777 23,949 0.0014
2021-02-16 2020-12-31 13F AMBAC FINL GROUP COM NEW 023139884 1,408,861 -39,030 -2.70 21,668 17.19 0.0013
2020-11-10 2020-09-30 13F AMBAC FINL GROUP COM NEW 023139884 1,447,891 -38,104 -2.56 18,490 -13.11 0.0013
2020-08-14 2020-06-30 13F AMBAC FINL GROUP COM NEW 023139884 1,485,995 -10,727 -0.72 21,279 15.21 0.0015
2020-06-19 2020-03-31 13F/A-1 AMBAC FINL GROUP COM NEW 023139884 1,496,722 111,927 8.08 18,470 -38.17 0.0016
2020-05-11 2020-03-31 13F AMBAC FINL GROUP COM NEW 023139884 1,496,722 111,927 18,470 1,622.0379
2020-02-06 2019-12-31 13F AMBAC FINL GROUP COM NEW 023139884 1,384,795 25,449 1.87 29,870 12.40 0.0020
2019-11-14 2019-09-30 13F AMBAC FINL GROUP COM NEW 023139884 1,359,346 15,932 1.19 26,575 17.40 0.0020
2019-08-14 2019-06-30 13F AMBAC FINL GROUP COM NEW 023139884 1,343,414 46,171 3.56 22,637 -3.70 0.0017
2019-05-15 2019-03-31 13F AMBAC FINL GROUP COM NEW 023139884 1,297,243 53,246 4.28 23,506 9.60 0.0018
2019-02-12 2018-12-31 13F AMBAC FINL GROUP COM NEW 023139884 1,243,997 -20,630 -1.63 21,447 -16.94 0.0020
2018-11-09 2018-09-30 13F AMBAC FINANCIAL GROUP Common equity shares 023139884 1,264,627 86,156 7.31 25,822 10.36 0.0020
2018-08-14 2018-06-30 13F AMBAC FINANCIAL GROUP Common equity shares 023139884 1,178,471 235,102 24.92 23,397 58.23 0.0020
2018-05-15 2018-03-31 13F AMBAC FINANCIAL GROUP Common equity shares 023139884 943,369 -3,241 -0.34 14,787 -2.23 0.0013
2018-02-14 2017-12-31 13F AMBAC FINANCIAL GROUP Common equity shares 023139884 946,610 50,238 5.60 15,125 -2.24 0.0012
2017-11-14 2017-09-30 13F AMBAC FINANCIAL GROUP Common equity shares 023139884 896,372 -1,790 -0.20 15,471 -0.72 0.0013
2017-08-14 2017-06-30 13F AMBAC FINANCIAL GROUP Common equity shares 023139884 898,162 29,767 3.43 15,583 -4.87 0.0014
2017-05-15 2017-03-31 13F AMBAC FINANCIAL GROUP Common equity shares 023139884 868,395 6,732 0.78 16,381 -15.52 0.0015
2017-02-09 2016-12-31 13F AMBAC FINANCIAL GROUP Common equity shares 023139884 861,663 54,215 6.71 19,390 30.56 0.0018
2017-01-13 2016-09-30 13F/A-1 AMBAC FINANCIAL GROUP Common equity shares 023139884 807,448 11,861 1.49 14,851 13.41 0.0015
2016-11-14 2016-09-30 13F AMBAC FINANCIAL GROUP Common equity shares 023139884 807,448 14,851
2016-08-12 2016-06-30 13F AMBAC FINANCIAL GROUP Common equity shares 023139884 795,587 2,477 0.31 13,095 4.47 0.0014
2016-05-20 2016-03-31 13F/A-1 AMBAC FINANCIAL GROUP Common equity shares 023139884 793,110 9,419 1.20 12,535 13.59 0.0014
2016-05-12 2016-03-31 13F AMBAC FINANCIAL GROUP Common equity shares 023139884 793,110 12,535
2016-02-16 2015-12-31 13F AMBAC FINANCIAL GROUP Common equity shares 023139884 783,691 18,347 2.40 11,035 -0.38 0.0012
2015-11-16 2015-09-30 13F AMBAC FINANCIAL GROUP Common equity shares 023139884 765,344 -16,328 -2.09 11,077 -14.86 0.0013
2015-08-13 2015-06-30 13F AMBAC FINANCIAL GROUP Common equity shares 023139884 781,672 14,960 1.95 13,010 -29.88 0.0014
2015-05-15 2015-03-31 13F AMBAC FINANCIAL GROUP Common equity shares 023139884 766,712 37,260 5.11 18,555 3.83 0.0019
2015-02-11 2014-12-31 13F AMBAC FINANCIAL GROUP Common equity shares 023139884 729,452 -2,478 -0.34 17,871 10.46 0.0018
2014-11-12 2014-09-30 13F/A-1 AMBAC FINANCIAL GROUP Common equity shares 023139884 731,930 -58,459 -7.40 16,178 -25.05 0.0017
2014-11-10 2014-09-30 13F AMBAC FINANCIAL GROUP Common equity shares 023139884 731,930 16,178
2014-08-12 2014-06-30 13F AMBAC FINANCIAL GROUP Common equity shares 023139884 790,389 27,333 3.58 21,586 -8.84 0.0023
2014-05-15 2014-03-31 13F/A-1 AMBAC FINANCIAL GROUP Common equity shares 023139884 763,056 -5,347 -0.70 23,679 25.46 0.0027
2014-05-13 2014-03-31 13F AMBAC FINANCIAL GROUP Common equity shares 023139884 763,256 23,685
2014-02-06 2013-12-31 13F/A-1 AMBAC FINANCIAL GROUP Common equity shares 023139884 768,403 52,864 7.39 18,874 45.42 0.0021
2013-11-12 2013-09-30 13F AMBAC FINANCIAL GROUP Common equity shares 023139884 715,539 59,739 9.11 12,979 -16.95 0.0016
2013-08-08 2013-06-30 13F AMBAC FINANCIAL GROUP Common equity shares 023139884 655,800 655,800 15,627 0.0020
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.