<SEC-DOCUMENT>0000874501-17-000066.txt : 20170516
<SEC-HEADER>0000874501-17-000066.hdr.sgml : 20170516
<ACCEPTANCE-DATETIME>20170516165944
ACCESSION NUMBER:		0000874501-17-000066
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		2
CONFORMED PERIOD OF REPORT:	20170512
FILED AS OF DATE:		20170516
DATE AS OF CHANGE:		20170516

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:			Eisman Robert Bryan
		CENTRAL INDEX KEY:			0001477761

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-10777
		FILM NUMBER:		17849370

	MAIL ADDRESS:	
		STREET 1:		AMBAC FINANCIAL GROUP INC.
		STREET 2:		ONE STATE STREET PLAZA
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10004
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>wf-form4_149496836945155.xml
<DESCRIPTION>FORM 4
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2017-05-12</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

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

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001477761</rptOwnerCik>
            <rptOwnerName>Eisman Robert Bryan</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>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Sr. MD &amp; CAO</officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2017-05-12</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>2979</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                    <footnoteId id="F1"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>8668</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2017-05-12</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>F</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>1399</value>
                    <footnoteId id="F2"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>17.18</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>7269</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">The reporting person acquired 2,979 shares of common stock of Ambac Financial Group, Inc. (the &quot;Company&quot;) upon the simultaneous vesting and settlement of the reporting person's 2014 Long Term Incentive Plan award, which had a three year performance period and vested on May 12, 2017.</footnote>
        <footnote id="F2">As part of this vesting and settlement, 1,399 shares of common stock were withheld by the Company to satisfy certain tax withholding obligations.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>William J. White, attorney-in-fact</signatureName>
        <signatureDate>2017-05-16</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
<DOCUMENT>
<TYPE>EX-24
<SEQUENCE>2
<FILENAME>poa-robertbeismanforedgari.htm
<DESCRIPTION>POWER OF ATTORNEY
<TEXT>
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<pre>

                                                 POWER OF ATTORNEY



            I, ROBERT B. EISMAN, do hereby nominate, constitute and appoint each of William White, Stephen M. Ksenak and Yolanda Ortiz, as my true and lawful agent and attorney-in-fact, with full power and authority to act hereunder, in his or her discretion, in my name and on my behalf as fully as I could if I were present and acting in person, to make any and all required or voluntary filings under Section 16(a) of the Securities Exchange Act of 1934, as amended (the "Exchange Act"), and the applicable rules and regulations thereunder, with the Securities and Exchange Commission, the New York Stock Exchange, Ambac Financial Group, Inc., a Delaware corporation (the "Company"), and any other person or entity to which such filings may be required under Section 16(a) of the Exchange Act as a result of my service as an officer of the Company or beneficial ownership (within the meaning of Section 16(a) of the Exchange Act) of more than ten percent of any class of equity securities of the Company.

            I hereby consent to, ratify and confirm all that each said attorney-in-fact shall do or cause to be done by virtue of this Power of Attorney.  I hereby acknowledge that each attorney-in-fact, in serving in such capacity at my request, is not assuming, nor is the Company assuming, any of my responsibilities to comply with Section 16 of the Exchange Act.

            This Power of Attorney shall remain in full force and effect from this date forward for so long as I am an officer or director of the Company and for such time thereafter as may be necessary to make any such filings or until revoked or modified by me.  I hereby revoke all prior powers of attorney relating to the foregoing acts.

            IN WITNESS WHEREOF, I have hereunto signed my name this 17th day of December, 2013.




                            __ /s/ Robert B. Eisman___







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</SEC-DOCUMENT>
