-----BEGIN PRIVACY-ENHANCED MESSAGE-----
Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
Originator-Key-Asymmetric:
 MFgwCgYEVQgBAQICAf8DSgAwRwJAW2sNKK9AVtBzYZmr6aGjlWyK3XmZv3dTINen
 TWSM7vrzLADbmYQaionwg5sDW3P6oaM5D3tdezXMm7z1T+B+twIDAQAB
MIC-Info: RSA-MD5,RSA,
 WR64h0+PvMOz7aAMjK/4oQtJkoEn56DhjRFl88pdFO8wiwWbjMXAugzhF80eV6DS
 kZMCwjFWvqNu8OgGWMrtaA==

<SEC-DOCUMENT>0001187615-09-000002.txt : 20091223
<SEC-HEADER>0001187615-09-000002.hdr.sgml : 20091223
<ACCEPTANCE-DATETIME>20091223093838
ACCESSION NUMBER:		0001187615-09-000002
CONFORMED SUBMISSION TYPE:	3
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20091216
FILED AS OF DATE:		20091223
DATE AS OF CHANGE:		20091223

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			BRENNER KAREN
		CENTRAL INDEX KEY:			0001187615

	FILING VALUES:
		FORM TYPE:		3
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-09371
		FILM NUMBER:		091256788

	MAIL ADDRESS:	
		STREET 1:		50 GAST 77 ST
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10021

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			ALLEGHANY CORP /DE
		CENTRAL INDEX KEY:			0000775368
		STANDARD INDUSTRIAL CLASSIFICATION:	FIRE, MARINE & CASUALTY INSURANCE [6331]
		IRS NUMBER:				510283071
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		375 PARK AVENUE
		STREET 2:		SUITE 3201
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10152
		BUSINESS PHONE:		2127521356

	MAIL ADDRESS:	
		STREET 1:		375 PARK AVENUE
		STREET 2:		SUITE 3201
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10152

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	ALLEGHANY FINANCIAL CORP
		DATE OF NAME CHANGE:	19870115
</SEC-HEADER>
<DOCUMENT>
<TYPE>3
<SEQUENCE>1
<FILENAME>primary_doc.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0203</schemaVersion>

    <documentType>3</documentType>

    <periodOfReport>2009-12-16</periodOfReport>

    <noSecuritiesOwned>1</noSecuritiesOwned>

    <issuer>
        <issuerCik>0000775368</issuerCik>
        <issuerName>ALLEGHANY CORP /DE</issuerName>
        <issuerTradingSymbol>Y</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001187615</rptOwnerCik>
            <rptOwnerName>BRENNER KAREN</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O ALLEGHANY CORPORATION</rptOwnerStreet1>
            <rptOwnerStreet2>7 TIMES SQUARE TOWER,17TH FLOOR</rptOwnerStreet2>
            <rptOwnerCity>NEW YORK</rptOwnerCity>
            <rptOwnerState>NY</rptOwnerState>
            <rptOwnerZipCode>10036</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <ownerSignature>
        <signatureName>Karen Brenner</signatureName>
        <signatureDate>2009-12-16</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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