-----BEGIN PRIVACY-ENHANCED MESSAGE-----
Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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MIC-Info: RSA-MD5,RSA,
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 p5lQsZLcjl+Eag0AzGPKFg==

<SEC-DOCUMENT>0001318148-10-000533.txt : 20100308
<SEC-HEADER>0001318148-10-000533.hdr.sgml : 20100308
<ACCEPTANCE-DATETIME>20100308162132
ACCESSION NUMBER:		0001318148-10-000533
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20100304
FILED AS OF DATE:		20100308
DATE AS OF CHANGE:		20100308

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:		10663997

	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>X0303</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2010-03-04</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>Executive VP</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Class B Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2010-03-04</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>5257</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>25.5912</value>
                    <footnoteId id="F2"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>32174</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">Represents a sale of shares to satisfy tax obligations arising from the vesting of restricted shares of stock.</footnote>
        <footnote id="F2">The price reported in Column 4 is a weighted average price.  These shares were sold in two transactions at prices ranging from $25.59 to $25.5915, inclusive.  The reporting person undertakes to provide to Federated Investors, Inc., any security holder of Federated Investors, Inc. or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote.</footnote>
    </footnotes>

    <remarks>The Power of Attorney dated July 17, 2009 is incorporated by reference.</remarks>

    <ownerSignature>
        <signatureName>/s/ Gail C. Jones  (Attorney-in-Fact)</signatureName>
        <signatureDate>2010-03-08</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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