-----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,
 Rrpw1FuT820H1+8Jy8P5IdpDpva3Cjye2z1ydG3GxhaD6daAg+hzq/eyKvtmLhs2
 JrBKBGlxywRYqiPLLd+sqw==

<SEC-DOCUMENT>0001061444-08-000001.txt : 20080306
<SEC-HEADER>0001061444-08-000001.hdr.sgml : 20080306
<ACCEPTANCE-DATETIME>20080306151901
ACCESSION NUMBER:		0001061444-08-000001
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20080304
FILED AS OF DATE:		20080306
DATE AS OF CHANGE:		20080306

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			MALONEY EUGENE F
		CENTRAL INDEX KEY:			0001061444

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-14818
		FILM NUMBER:		08670783

	BUSINESS ADDRESS:	
		BUSINESS PHONE:		1-800-341-7400

	MAIL ADDRESS:	
		STREET 1:		FEDERATED INVESTORS TOWER
		STREET 2:		1001 LIBERTY AVENUE
		CITY:			PITTSBURGH
		STATE:			PA
		ZIP:			15222-3779

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			FEDERATED INVESTORS INC /PA/
		CENTRAL INDEX KEY:			0001056288
		STANDARD INDUSTRIAL CLASSIFICATION:	INVESTMENT ADVICE [6282]
		IRS NUMBER:				251111467
		STATE OF INCORPORATION:			PA
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		FEDERATED INVESTORS TOWER
		STREET 2:		5800 CORPORATE DR
		CITY:			PITTSBURGH
		STATE:			PA
		ZIP:			15222
		BUSINESS PHONE:		4122888141

	MAIL ADDRESS:	
		STREET 1:		FEDERATED INVESTORS TOWER
		CITY:			PITTSBURGH
		STATE:			PA
		ZIP:			15222
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>primary_doc.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2008-03-04</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001056288</issuerCik>
        <issuerName>FEDERATED INVESTORS INC /PA/</issuerName>
        <issuerTradingSymbol>FII</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001061444</rptOwnerCik>
            <rptOwnerName>MALONEY EUGENE F</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>FEDERATED INVESTORS TOWER</rptOwnerStreet1>
            <rptOwnerStreet2>1001 LIBERTY AVENUE</rptOwnerStreet2>
            <rptOwnerCity>PITTSBURGH</rptOwnerCity>
            <rptOwnerState>PA</rptOwnerState>
            <rptOwnerZipCode>15222-3779</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Vice President</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Class B Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2008-03-04</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>8146</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>33393</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <remarks>The Power of Attorney dated July 25, 2006 is incorporated by reference.</remarks>

    <ownerSignature>
        <signatureName>/s/ Gail C. Jones (Attorney-in-Fact)</signatureName>
        <signatureDate>2008-03-06</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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