<SEC-DOCUMENT>0000874501-18-000042.txt : 20180306
<SEC-HEADER>0000874501-18-000042.hdr.sgml : 20180306
<ACCEPTANCE-DATETIME>20180306175745
ACCESSION NUMBER:		0000874501-18-000042
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		2
CONFORMED PERIOD OF REPORT:	20180302
FILED AS OF DATE:		20180306
DATE AS OF CHANGE:		20180306

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			BARRANCO DAVID
		CENTRAL INDEX KEY:			0001562313

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-10777
		FILM NUMBER:		18671191

	MAIL ADDRESS:	
		STREET 1:		C/O AMBAC FINANCIAL GROUP INC
		STREET 2:		ONE STATE STREET PLAZA
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10004

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
</SEC-HEADER>
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<DESCRIPTION>FORM 4
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    <periodOfReport>2018-03-02</periodOfReport>

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    <issuer>
        <issuerCik>0000874501</issuerCik>
        <issuerName>AMBAC FINANCIAL GROUP INC</issuerName>
        <issuerTradingSymbol>AMBC</issuerTradingSymbol>
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        <reportingOwnerId>
            <rptOwnerCik>0001562313</rptOwnerCik>
            <rptOwnerName>BARRANCO DAVID</rptOwnerName>
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        <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>
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        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Senior Managing Director</officerTitle>
            <otherText></otherText>
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                    <value>1589.0</value>
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                    <value>6808</value>
                </sharesOwnedFollowingTransaction>
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                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
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        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">Represents the aggregate amount of Deferred Share Units (&quot;DSUs&quot;) that were converted into shares of common stock of Ambac Financial Group, Inc. (the &quot;Company&quot;) upon settlement of a portion of the reporting person's 2016 and 2017 Short Term Incentive award.</footnote>
        <footnote id="F2">Represents the aggregate amount of DSUs that were converted into shares of common stock and withheld by the Company to satisfy certain tax withholding obligations.</footnote>
        <footnote id="F3">Each restricted stock unit (&quot;RSUs&quot;)represents a contingent right to receive one share of common stock of the Company.</footnote>
        <footnote id="F4">On March 2, 2018 the reporting person received a grant of 6,627 RSUs as part of their 2018 Long Term Incentive Plan award. The RSUs will vest in three equal annual installments on each of March 2, 2019, March 2, 2020, and March 2, 2021.</footnote>
        <footnote id="F5">Each DSU represents a contingent right to receive one share of the Company's common stock.</footnote>
        <footnote id="F6">On March 2, 2018, there were 5,700 DSUs granted as part of the 2018 Short Term Incentive Plan. The DSUs shall vest immediately and shall settle and convert into shares of common stock as follows: 50% of the DSUs shall settle and convert into shares of common stock on March 2, 2019, and the remaining 50% of the DSUs shall settle and convert into shares of common stock on March 2, 2020; provided however, that if the reporting person's employment with the Company is terminated for any reason, all of the DSUs will settle and convert into shares of common stock immediately. Notwithstanding the foregoing, a number of vested DSUs sufficient to satisfy certain tax withholding obligations imposed upon the Company may be converted into shares of common stock and withheld by the Company to satisfy such tax withholding obligations.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>William J. White, attorney-in-fact</signatureName>
        <signatureDate>2018-03-06</signatureDate>
    </ownerSignature>
</ownershipDocument>
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<DOCUMENT>
<TYPE>EX-24
<SEQUENCE>2
<FILENAME>poa-davidbarrancoforedgari.htm
<DESCRIPTION>POWER OF ATTORNEY, EXHIBIT 24
<TEXT>
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                                            POWER OF ATTORNEY



            I, DAVID BARRANCO, 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/ David Barranco___






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