<SEC-DOCUMENT>0001127602-25-008126.txt : 20250304
<SEC-HEADER>0001127602-25-008126.hdr.sgml : 20250304
<ACCEPTANCE-DATETIME>20250304210013
ACCESSION NUMBER:		0001127602-25-008126
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20250301
FILED AS OF DATE:		20250304
DATE AS OF CHANGE:		20250304

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Thomas Toby L.
		CENTRAL INDEX KEY:			0002002091
		ORGANIZATION NAME:           	

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	333-21011
		FILM NUMBER:		25708313

	MAIL ADDRESS:	
		STREET 1:		76 S. MAIN ST
		CITY:			AKRON
		STATE:			OH
		ZIP:			44308

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			FIRSTENERGY CORP
		CENTRAL INDEX KEY:			0001031296
		STANDARD INDUSTRIAL CLASSIFICATION:	ELECTRIC SERVICES [4911]
		ORGANIZATION NAME:           	01 Energy & Transportation
		IRS NUMBER:				341843785
		STATE OF INCORPORATION:			OH
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		76 SOUTH MAIN ST
		CITY:			AKRON
		STATE:			OH
		ZIP:			44308-1890
		BUSINESS PHONE:		330-761-7837

	MAIL ADDRESS:	
		STREET 1:		76 SOUTH MAIN ST
		CITY:			AKRON
		STATE:			OH
		ZIP:			44308-1890
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>form4.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
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    <schemaVersion>X0508</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2025-03-01</periodOfReport>

    <issuer>
        <issuerCik>0001031296</issuerCik>
        <issuerName>FIRSTENERGY CORP</issuerName>
        <issuerTradingSymbol>FE</issuerTradingSymbol>
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        <reportingOwnerId>
            <rptOwnerCik>0002002091</rptOwnerCik>
            <rptOwnerName>Thomas Toby L.</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>76 S. MAIN ST</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>AKRON</rptOwnerCity>
            <rptOwnerState>OH</rptOwnerState>
            <rptOwnerZipCode>44308</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isOfficer>1</isOfficer>
            <officerTitle>Chief Operating Officer</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <aff10b5One>0</aff10b5One>

    <nonDerivativeTable>
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                <value>Common Stock</value>
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                <transactionFormType>4</transactionFormType>
                <transactionCode>M</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
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            <transactionTimeliness></transactionTimeliness>
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                    <value>12622</value>
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                    <value>24792.562</value>
                </sharesOwnedFollowingTransaction>
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                    <value>D</value>
                </directOrIndirectOwnership>
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            <securityTitle>
                <value>Common Stock</value>
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        <nonDerivativeHolding>
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                <value>Common Stock</value>
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            <ownershipNature>
                <directOrIndirectOwnership>
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                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By Savings Plan</value>
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        </nonDerivativeHolding>
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                <transactionShares>
                    <value>12622</value>
                </transactionShares>
                <transactionPricePerShare>
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            <expirationDate>
                <footnoteId id="F1"/>
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                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
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                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
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        </derivativeTransaction>
        <derivativeTransaction>
            <securityTitle>
                <value>Phantom 3/25D</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <footnoteId id="F7"/>
            </conversionOrExercisePrice>
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                <value>2025-03-01</value>
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                <transactionFormType>4</transactionFormType>
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            <transactionAmounts>
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                    <value>10728</value>
                </transactionShares>
                <transactionPricePerShare>
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                    <value>Common Stock</value>
                </underlyingSecurityTitle>
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                    <value>10728</value>
                </underlyingSecurityShares>
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                <sharesOwnedFollowingTransaction>
                    <value>10728</value>
                </sharesOwnedFollowingTransaction>
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                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
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        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">Represents the vesting of performance-adjusted restricted stock units (&quot;RSUs&quot;), each of which previously represented a contingent right to receive an RSU award payable in shares of common stock of FirstEnergy Corp. (the &quot;Company&quot;) (&quot;Share-Based RSUs&quot;) following the vesting date. The satisfaction of the performance goals for the RSUs were certified by the Company's Board of Directors on February 5, 2025, as previously reported on a Form 4 filed on February 7, 2025, and the RSUs, which had remained subject to a continued service requirement, vested on March 1, 2025.</footnote>
        <footnote id="F2">The RSUs converted into shares of the Company's common stock on a one-for-one basis under the FirstEnergy Corp. 2020 Incentive Compensation Plan.</footnote>
        <footnote id="F3">Represents shares withheld to cover tax obligations associated with the vesting of the 20PSUS21 award.</footnote>
        <footnote id="F4">In connection with the vesting of the Share-Settled RSUs on March 1, 2025, the reporting person's receipt of 10,728 shares of the Company's common stock was deferred, resulting in the reporting person receiving instead 10,728 shares of phantom stock pursuant to the Company's deferred compensation plan. The reporting person is therefore reporting the disposition of 10,728 shares of common stock in exchange for an equal number of shares of phantom stock.</footnote>
        <footnote id="F5">The Company's 401(k) Savings Plan includes a unitized fund invested in shares of common stock of the Company, in which the reporting person may invest, and includes dividend reinvestment and company match features. The number of shares reported as indirectly held in the 401(K) Savings Plan in this row is an estimate of the number of shares of the Company's common stock held in the unitized stock fund since the reporting person's last filed Form 4 and as allocated to the reporting person's account as of February 28, 2025.</footnote>
        <footnote id="F6">Share-Based RSUs convert into the Company's common stock on a one-for-one basis.</footnote>
        <footnote id="F7">Each share of phantom stock represents a right to receive one share of the Company's common stock.</footnote>
        <footnote id="F8">The phantom stock becomes payable upon the reporting person's death, disability or termination of employment with the Company.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ Mary M. Swann, attorney-in-fact</signatureName>
        <signatureDate>2025-03-04</signatureDate>
    </ownerSignature>
</ownershipDocument>
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</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
