<SEC-DOCUMENT>0001144204-13-068796.txt : 20131223
<SEC-HEADER>0001144204-13-068796.hdr.sgml : 20131223
<ACCEPTANCE-DATETIME>20131223174508
ACCESSION NUMBER:		0001144204-13-068796
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20131220
FILED AS OF DATE:		20131223
DATE AS OF CHANGE:		20131223

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			AMBAC FINANCIAL GROUP INC
		CENTRAL INDEX KEY:			0000874501
		STANDARD INDUSTRIAL CLASSIFICATION:	SURETY INSURANCE [6351]
		IRS NUMBER:				133621676
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		ONE STATE ST PLZ
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10004
		BUSINESS PHONE:		2126680340

	MAIL ADDRESS:	
		STREET 1:		ONE STATE ST PLZ
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10004

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	AMBAC INC /DE/
		DATE OF NAME CHANGE:	19930328

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Stein Jeffrey Scott
		CENTRAL INDEX KEY:			0001559518

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-10777
		FILM NUMBER:		131295970

	MAIL ADDRESS:	
		STREET 1:		601 TRAVIS
		STREET 2:		SUITE 1400
		CITY:			HOUSTON
		STATE:			TX
		ZIP:			77002
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>v363822_4.xml
<DESCRIPTION>OWNERSHIP DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2013-12-20</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000874501</issuerCik>
        <issuerName>AMBAC FINANCIAL GROUP INC</issuerName>
        <issuerTradingSymbol>AMBC</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001559518</rptOwnerCik>
            <rptOwnerName>Stein Jeffrey Scott</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>AMBAC FINANCIAL GROUP, INC.</rptOwnerStreet1>
            <rptOwnerStreet2>ONE STATE STREET PLAZA</rptOwnerStreet2>
            <rptOwnerCity>NEW YORK</rptOwnerCity>
            <rptOwnerState>NY</rptOwnerState>
            <rptOwnerZipCode>10004</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle></officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Restricted Stock Units</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <footnoteId id="F1"/>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2013-12-20</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness></transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>18179</value>
                </transactionShares>
                <transactionPricePerShare>
                    <footnoteId id="F3"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F2"/>
            </exerciseDate>
            <expirationDate>
                <footnoteId id="F2"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>18179</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>18179</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
        <derivativeTransaction>
            <securityTitle>
                <value>Stock Option (Right to Buy)</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>20.63</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2013-12-20</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness></transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>16667</value>
                </transactionShares>
                <transactionPricePerShare>
                    <footnoteId id="F3"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <value>2014-04-30</value>
            </exerciseDate>
            <expirationDate>
                <value>2020-12-20</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>16667</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>16667</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">Each restricted stock unit (&quot;RSU&quot;) represents a contingent right to receive one share of the common stock of Ambac Financial Group, Inc. (the&quot; Company&quot;).</footnote>
        <footnote id="F2">The RSUs shall vest on April 30, 2014.  RSUs that have become vested shall settle and convert into shares of common stock upon the date that the reporting person resigns from, or otherwise ceases to be a member of, the Board of Directors of the Company.</footnote>
        <footnote id="F3">The RSUs and stock options were received as an award under the Company's Incentive Compensation Plan.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>Stephen M. Ksenak, attorney-in-fact</signatureName>
        <signatureDate>2013-12-23</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
