OCTAVE SPECIALTY GROUP INC - Common Stock, $0.01 par value per share (AMBC)

Historical Holders from Q1 2014 to Q3 2025

Symbol: AMBC on NYSE
CUSIP: 023139884
Type / Class: Equity / Common Stock, $0.01 par value per share
Shares outstanding: 46.2M
All holders as of September 30, 2025: Q3 2025
Total 13F shares, excl. options: 36.4M
Holdings value: $304M
% of all portfolios: 0.003%
Grand Portfolio weight change: +0%
Number of holders: 124
Number of buys: 61
Number of sells: -80
Average Value change %: +0%
Average buys %: +0.002%
Average sells %: -0.001%

Reported Shares, Excluding Options vs Price

Reported Value, Excluding Options

Total Investors

Significant Owners of OCTAVE SPECIALTY GROUP INC - Common Stock, $0.01 par value per share (AMBC)

Filer	Ownership	Change %	Holdings Value	Net Change	Nb Shares	Change %	Reporting Name	Report Period
BlackRock, Inc.	7.6%	-12.2%	$29.5M	-$3.89M	3.54M	-11.7%	BlackRock, Inc.	Sep 30, 2025
VANGUARD GROUP INC	5.75%	-14.6%	$17.4M	-$3.64M	2.66M	-17.3%	The Vanguard Group	Mar 31, 2025
DIMENSIONAL FUND ADVISORS LP	4.6%		$17.9M		2.14M		Dimensional Fund Advisors LP	Sep 30, 2025
SUSQUEHANNA SECURITIES, LLC	2.2%	-58%	$8.48M	-$11.4M	1.02M	-57.2%	G1 Execution Services, LLC	Sep 30, 2025

Institutional Holders of OCTAVE SPECIALTY GROUP INC - Common Stock, $0.01 par value per share (AMBC)

Period	Reported Shares, Excl. Options	Value, Excl. Options	Change	Puts Notional Value	Calls Notional Value	Price	Investors
2025 Q3	36.4M	$304M	+$5.42M	4.31M	41.8M	$8.34	124
2025 Q2	37M	$262M	-$6.28M	4.38M	69.4M	$7.10	145
2025 Q1	37.3M	$325M	-$39.5M	8.99M	84.6M	$8.75	170
2024 Q4	41.5M	$522M	+$19M	4.73M	56.7M	$12.65	179
2024 Q3	40M	$447M	+$7.16M	5.22M	26.7M	$11.21	179
2024 Q2	38.7M	$497M	+$11.2M	2.37M	7.11M	$12.82	184
2024 Q1	37.8M	$590M	-$4.92M	3.5M	7.35M	$15.63	171
2023 Q4	166K	$2.73M	-$1.23M			$16.48	1
2023 Q3	36.3M	$438M	-$11.5M	1.72M	2.05M	$12.06	164
2023 Q2	37.1M	$528M	-$27.7M	9.82M	1.43M	$14.24	158
2023 Q1	38.6M	$596M	+$64M	3.59M	7.27M	$15.48	156
2022 Q4	34.5M	$600M	+$61.6M	917K	7.55M	$17.44	163
2022 Q3	31.3M	$399M	-$50M	9.22M	17.9M	$12.75	144
2022 Q2	30.2M	$342M	-$36.5M	7M	7.19M	$11.35	134
2022 Q1	31.4M	$325M	-$4.86M	7.88M	6.14M	$10.40	138
2021 Q4	37M	$594M	+$13M	3.64M	10.1M	$16.05	126
2021 Q3	35.9M	$514M	-$1.61M	2.51M	5.71M	$14.32	126
2021 Q2	36M	$563M	-$8.57M	1.3M	4.14M	$15.66	121
2021 Q1	36.4M	$609M	-$26.7M	3.73M	7.35M	$16.74	135
2020 Q4	35.9M	$552M	-$5.6M	2.68M	17M	$15.38	131
2020 Q3	34.5M	$440M	-$16.9M	1.21M	9.12M	$12.77	123
2020 Q2	37.2M	$532M	+$19.5M	1.22M	5.72M	$14.32	132
2020 Q1	35.8M	$441M	-$9.24M	1.25M	3.62M	$12.34	119
2019 Q4	36.7M	$791M	+$9.33M	1.43M	24.3M	$21.57	129
2019 Q3	36M	$703M	-$19.2M	2.17M	22.7M	$19.55	123
2019 Q2	35.7M	$601M	+$22.1M	3.09M	41.3M	$16.85	127
2019 Q1	34.2M	$620M	-$21M	2.03M	20.8M	$18.12	149
2018 Q4	36.1M	$622M	+$43.6M	2.86M	8.7M	$17.24	141
2018 Q3	35.3M	$722M	-$25.5M	14.2M	47.8M	$20.42	150
2018 Q2	36.6M	$726M	+$48.9M	12.3M	27.4M	$19.85	141
2018 Q1	34M	$532M	+$6.93M	4.28M	29.3M	$15.68	110
2017 Q4	32.5M	$519M	-$8.82M	4.16M	28.7M	$15.98	112
2017 Q3	31.8M	$548M	-$23.9M	70.3M	14M	$17.26	117
2017 Q2	33.1M	$575M	-$6.66M	5.63M	11.4M	$17.35	124
2017 Q1	33.4M	$629M	+$44M	5.9M	19.6M	$18.86	141
2016 Q4	32.8M	$738M	-$6.13M	4.89M	17.4M	$22.50	147
2016 Q3	32.1M	$590M	-$10.1M	1.77M	3.39M	$18.39	118
2016 Q2	30.4M	$500M	+$5.1M	1.1M	768K	$16.46	123
2016 Q1	32.1M	$508M	-$25.3M	528K	678K	$15.80	113
2015 Q4	34.1M	$481M	-$4.61M	1.12M	862K	$14.09	126
2015 Q3	34.4M	$497M	-$3.99M	4.09M	9.49M	$14.47	124
2015 Q2	34.3M	$571M	+$5.18M	13M	34.8M	$16.64	123
2015 Q1	33.6M	$813M	+$33.2M	13.7M	22.3M	$24.20	120
2014 Q4	31.4M	$769M	-$48.4M	13.8M	54.5M	$24.50	119
2014 Q3	34.6M	$765M	-$50.1M	18.3M	39.2M	$22.10	113
2014 Q2	36.1M	$986M	+$9.07M	12.4M	16.9M	$27.31	121
2014 Q1	35.7M	$1.11B	+$119M	19.6M	66.3M	$31.03	132