Ambac Financial Group, Inc.
Ambac Financial Group, Inc. (AMBC) Stock Ownership
Institutional vs insider vs public ownership from 13F and float data — top holders, activity, and insider trades below.
SEC 13F · FMP · AMBC · as of Sep 30, 2025
Ownership Breakdown
148
Institutional Holders
▼ 12 vs Q2
$539.38M
Total Inst. Value
▲ $276.93M vs Q2
47.93M
Shares Outstanding
freeFloat 79.80%
37.64M
13F Shares Held
▲ 676,718 vs Q2
Institutional ownership = 13F shares ÷ total outstanding. Insider % = 100 − free float. Public % = free float − institution %. Data: FMP /symbol-positions-summary + /shares-float + SEC EDGAR.
Top Institutional Holders
AMBC largest shareholders · institutional ownership
Q3 2025 · SEC 13F
Showing top 10 holders
| Holder | Shares | % Owned | Weight | Value | Reported | Change |
|---|---|---|---|---|---|---|
BLACKROCK, INC. surety insurance | 4.49M | 9.34% | 9.34% | $37.47B | Nov 12, 2025 | ▼ 94.7K |
WESTERN STANDARD LLC surety insurance | 2.64M | 5.49% | 5.49% | $22.03B | Nov 12, 2025 | ▲ 2.64M |
VANGUARD GROUP INC surety insurance | 2.56M | 5.31% | 5.31% | $21.31B | Nov 7, 2025 | ▼ 13.3K |
DIMENSIONAL FUND ADVISORS LP surety insurance | 2.14M | 4.45% | 4.45% | $17.86B | Nov 12, 2025 | ▼ 254.7K |
CONTINENTAL GENERAL INSURANCE CO surety insurance | 2.07M | 4.30% | 4.30% | $17.25B | Nov 13, 2025 | ▲ 850.0K |
GENDELL JEFFREY L surety insurance | 1.86M | 3.88% | 3.88% | $15.55B | Nov 14, 2025 | ▲ 666.1K |
FMR LLC surety insurance | 1.53M | 3.17% | 3.17% | $12.72B | Nov 13, 2025 | ▼ 7.2K |
MANUFACTURERS LIFE INSURANCE COMPANY, THE surety insurance | 1.21M | 2.51% | 2.51% | $232.01B | Nov 14, 2025 | ▲ 1.19M |
WOLF HILL CAPITAL MANAGEMENT, LP surety insurance | 1.16M | 2.41% | 2.41% | $9.66B | Nov 14, 2025 | ▲ 464.8K |
CAPTION MANAGEMENT, LLC surety insurance | 1.12M | 2.33% | 2.33% | $9.35B | Nov 14, 2025 | ▲ 945.1K |
Data from SEC Form 13F filings. Ownership bar normalised to largest holder. Change flags: isNew / isSoldOut / changeInSharesNumber (FMP extract-analytics/holder).
Institutional Activity
Q3 2025 vs prior quarter
Q3 2025
21
Increased
+11.14M shares1
New Positions
first time holders24
Decreased
−5.87M shares0
Sold Out
fully exitedNet shares change (top 50)
+5.27M
+11.14M / −5.87M
Net new holders
-2
1 new / 0 exited
Based on top 50 institutional holders by position size. Fields: isNew, isSoldOut, changeInSharesNumber (FMP extract-analytics/holder, limit=50).
Insider Buying vs Selling
AMBC insider trading · insider activity
Source: SEC Form 4
18
Buy transactions
1
Sell transactions
18.00
Buy/Sell ratio
$0M
Total disposed
Recent Insider Transactions
Showing 10 most recent · Common Stock only
No recent insider transactions reported.
Source: /insider-trading/search (FMP stable). Buy/Sell direction: acquisitionOrDisposition A=Buy, D=Sell. RSU vesting (M-Exempt) excluded from sentiment bar. All data from SEC EDGAR public filings.
About institutional & insider ownership
Ambac Financial Group, Inc. (AMBC) is primarily owned by institutional investors, who hold approximately 78.5% of total shares outstanding. Company insiders own approximately 20.20%, while retail and public investors account for the remaining 1.26%.
The largest institutional shareholder of Ambac Financial Group, Inc. is BLACKROCK, INC., holding approximately 4.49 million shares — equal to 9.34% of outstanding shares — as of September 30, 2025.
A total of 148 institutional investors currently hold AMBC stock, with a combined institutional value of approximately $539,381,717 as of the most recent 13F filing period.
Frequently asked questions
AMBC ownershipAmbac Financial Group, Inc. (AMBC) is primarily owned by institutional investors, who hold approximately 78.5% of shares. The largest shareholder is BLACKROCK, INC. with a 9.34% stake. Company insiders hold 20.20%. Data sourced from SEC Form 13F as of September 30, 2025.