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

13F Institutional Holders and Ownership History from Q1 2014 to Q4 2025

Type / Class
Equity / Common Stock, $0.01 par value per share
Symbol
OSG on NYSE
Shares outstanding
46,241,273
Price per share
$7.78
All holders as of 30 Sep 2025
Q3 2025
Total 13F shares
36,420,468
Total reported value
$303,620,015
% of total 13F portfolios
0%
Share change
+233,587
Value change
+$5,517,660
Number of holders
125
Price from insider filings
$7.78
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 (OSG) based on Schedule 13D/G filings

Filer Ownership Change % Holdings Value Net Change Nb Shares Change % Reporting Name Report Period
BlackRock, Inc. 7.6% -12% $29,497,691 -$3,891,879 3,535,664 -12% BlackRock, Inc. 30 Sep 2025
VANGUARD GROUP INC 5.8% -15% $20,621,836 -$4,302,536 2,660,882 -17% The Vanguard Group 31 Mar 2025
DIMENSIONAL FUND ADVISORS LP 4.6% $17,855,690 2,141,047 Dimensional Fund Advisors LP 30 Sep 2025
SUSQUEHANNA SECURITIES, LLC 2.2% -58% $8,484,349 -$11,354,702 1,017,308 -57% G1 Execution Services, LLC 30 Sep 2025

As of 30 Sep 2025, 125 institutional investors reported holding 36,420,468 shares of OCTAVE SPECIALTY GROUP INC - Common Stock, $0.01 par value per share (OSG). This represents 79% of the company’s total 46,241,273 outstanding shares.

Top 25 Institutional Shareholders

The largest institutional shareholders of OCTAVE SPECIALTY GROUP INC - Common Stock, $0.01 par value per share (OSG) together control 67% of the company’s outstanding shares — a level of ownership often associated with strong institutional conviction and long‑term capital commitment.

Institution Ownership % Shares Held Share Change % Portfolio % Holdings Value
BlackRock, Inc. 9.7% 4,493,331 -2.1% 0% $37,474,381
Western Standard LLC 5.7% 2,641,351 12% $22,028,867
VANGUARD GROUP INC 5.5% 2,555,181 -0.52% 0% $21,310,209
DIMENSIONAL FUND ADVISORS LP 4.6% 2,141,047 -11% 0% $17,860,855
CONTINENTAL GENERAL INSURANCE CO 4.5% 2,068,349 +70% 3.3% $17,250,031
GENDELL JEFFREY L 4% 1,864,512 +56% 0.29% $15,550,030
FMR LLC 3.3% 1,525,423 -0.47% 0% $12,722,027
Wolf Hill Capital Management, LP 2.5% 1,158,197 +67% 0.92% $9,659,363
Caption Management, LLC 2.4% 1,121,179 +537% 0.54% $9,350,633
Bain Capital Credit, LP 2.4% 1,108,012 0% 2.9% $9,240,820
Nuveen, LLC 2.3% 1,079,328 +131% 0% $9,001,596
GEODE CAPITAL MANAGEMENT, LLC 2.3% 1,060,594 -5.5% 0% $8,847,450
STATE STREET CORP 2.1% 967,188 +0.87% 0% $8,066,348
Prescott Group Capital Management, L.L.C. 1.9% 895,977 +2.3% 0.79% $7,472,448
JANE STREET GROUP, LLC 1.8% 849,182 +66% 0.01% $7,082,177
MILLENNIUM MANAGEMENT LLC 1.5% 700,895 -30% 0% $5,845,464
BARCLAYS PLC 1.4% 669,513 +47% 0% $5,583,740
THIRD AVENUE MANAGEMENT LLC 1.3% 603,391 0% 0.92% $4,905,569
Bracebridge Capital, LLC 1.3% 579,234 0% 2% $4,830,812
Schonfeld Strategic Advisors LLC 1.2% 548,442 +92% 0.03% $4,574,006
DEUTSCHE BANK AG\ 1.2% 532,138 -18% 0% $4,438,031
GOLDMAN SACHS GROUP INC 1.1% 524,890 +9.5% 0% $4,377,583
MARSHALL WACE, LLP 0.98% 455,074 -30% 0% $3,795,318
CHARLES SCHWAB INVESTMENT MANAGEMENT INC 0.83% 382,572 -1.4% 0% $3,190,650
NORTHERN TRUST CORP 0.78% 362,021 -6.9% 0% $3,019,255

Institutional Holders of OCTAVE SPECIALTY GROUP INC - Common Stock, $0.01 par value per share (OSG) across Reporting Periods

Period Reported Shares, Excl. Options Value, Excl. Options Value Change Price (Median) Investors
2025 Q4 407,994 $3,174,212 +$2,452,706 $7.78 8
2025 Q3 36,420,468 $303,620,015 +$5,517,660 $8.34 125
2025 Q2 36,967,187 $262,451,287 -$6,275,007 $7.10 145
2025 Q1 37,285,182 $325,247,075 -$39,529,091 $8.75 170
2024 Q4 41,463,461 $522,340,751 +$15,664,277 $12.65 179
2024 Q3 40,273,968 $449,624,914 +$10,695,609 $11.21 179
2024 Q2 38,733,238 $496,535,322 +$10,201,544 $12.82 182
2024 Q1 37,851,350 $591,468,537 -$4,976,804 $15.63 172
2023 Q4 38,145,550 $628,407,255 +$31,651,145 $16.48 174
2023 Q3 36,343,104 $438,745,752 -$11,313,309 $12.06 166
2023 Q2 37,227,104 $529,566,033 -$22,316,812 $14.24 159
2023 Q1 38,580,360 $596,164,176 +$63,723,924 $15.48 156
2022 Q4 34,499,926 $600,947,413 +$62,491,641 $17.44 165
2022 Q3 31,445,947 $401,072,377 -$34,274,712 $12.75 148
2022 Q2 36,839,151 $417,676,977 -$31,197,327 $11.35 137
2022 Q1 37,774,546 $392,130,695 -$17,253,058 $10.40 140
2021 Q4 37,338,742 $598,873,108 +$13,548,357 $16.05 129
2021 Q3 36,051,024 $516,212,696 -$1,311,166 $14.32 126
2021 Q2 36,096,104 $565,003,596 -$9,221,478 $15.66 122
2021 Q1 36,524,284 $611,655,331 -$28,313,721 $16.74 135
2020 Q4 37,401,411 $575,050,561 -$4,694,044 $15.38 134
2020 Q3 36,718,299 $468,543,199 -$11,638,357 $12.77 127
2020 Q2 37,390,881 $535,312,958 +$19,443,291 $14.32 133
2020 Q1 35,974,950 $443,933,094 -$8,960,245 $12.34 120
2019 Q4 36,664,639 $790,583,535 +$9,354,161 $21.57 130
2019 Q3 36,012,222 $703,986,865 -$23,174,466 $19.55 124
2019 Q2 37,365,566 $629,594,318 +$17,090,478 $16.85 129
2019 Q1 36,429,892 $660,092,503 -$23,814,953 $18.12 151
2018 Q4 38,125,046 $657,191,596 +$41,689,872 $17.24 142
2018 Q3 35,349,709 $721,784,264 -$25,492,986 $20.42 153
2018 Q2 36,584,891 $726,245,584 +$52,129,757 $19.85 143
2018 Q1 34,322,029 $538,042,869 +$6,516,697 $15.68 111
2017 Q4 34,019,895 $543,583,390 +$14,236,661 $15.98 113
2017 Q3 31,755,643 $548,132,061 -$23,887,203 $17.26 117
2017 Q2 33,154,459 $575,188,561 -$6,751,505 $17.35 125
2017 Q1 33,360,004 $629,149,540 +$44,338,708 $18.86 142
2016 Q4 32,791,759 $737,764,333 -$6,130,280 $22.50 148
2016 Q3 32,064,545 $589,656,481 -$8,127,283 $18.39 118
2016 Q2 32,596,504 $536,526,933 +$9,337,208 $16.46 124
2016 Q1 32,173,912 $508,240,305 -$24,875,093 $15.80 114
2015 Q4 34,137,929 $480,990,372 -$6,432,182 $14.09 126
2015 Q3 34,642,114 $501,121,270 -$6,297,784 $14.47 124
2015 Q2 34,791,281 $578,734,495 -$43,337,961 $16.64 124
2015 Q1 34,121,176 $825,674,265 -$16,973,261 $24.20 121
2014 Q4 32,996,996 $808,275,251 -$51,659,995 $24.50 121
2014 Q3 34,685,451 $765,847,490 -$49,754,474 $22.10 116
2014 Q2 36,183,801 $987,478,921 +$8,599,045 $27.31 124
2014 Q1 35,791,791 $1,109,815,486 +$86,633,202 $31.03 134