<SEC-DOCUMENT>0000886744-18-000045.txt : 20180824
<SEC-HEADER>0000886744-18-000045.hdr.sgml : 20180824
<ACCEPTANCE-DATETIME>20180824213213
ACCESSION NUMBER:		0000886744-18-000045
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20180824
FILED AS OF DATE:		20180824
DATE AS OF CHANGE:		20180824

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			ROSENFIELD STEPHEN
		CENTRAL INDEX KEY:			0001238623

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-20859
		FILM NUMBER:		181038008

	MAIL ADDRESS:	
		STREET 1:		PO BOX 174
		CITY:			SAN FRANCISCO
		STATE:			CA
		ZIP:			94116

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			GERON CORP
		CENTRAL INDEX KEY:			0000886744
		STANDARD INDUSTRIAL CLASSIFICATION:	PHARMACEUTICAL PREPARATIONS [2834]
		IRS NUMBER:				752287752
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1117

	BUSINESS ADDRESS:	
		STREET 1:		149 COMMONWEALTH DRIVE
		STREET 2:		SUITE 2070
		CITY:			MENLO PARK
		STATE:			CA
		ZIP:			94025
		BUSINESS PHONE:		6504737700

	MAIL ADDRESS:	
		STREET 1:		149 COMMONWEALTH DRIVE
		STREET 2:		SUITE 2070
		CITY:			MENLO PARK
		STATE:			CA
		ZIP:			94025

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	GERON CORPORATION
		DATE OF NAME CHANGE:	19960521
</SEC-HEADER>
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                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F5"/>
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            <transactionAmounts>
                <transactionShares>
                    <value>420000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
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                <transactionAcquiredDisposedCode>
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                </transactionAcquiredDisposedCode>
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            <exerciseDate>
                <footnoteId id="F1"/>
            </exerciseDate>
            <expirationDate>
                <value>2023-02-12</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>420000</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
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                <sharesOwnedFollowingTransaction>
                    <value>0</value>
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            <ownershipNature>
                <directOrIndirectOwnership>
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                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
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        </derivativeTransaction>
        <derivativeTransaction>
            <securityTitle>
                <value>Stock Option (Right to Buy)</value>
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            <conversionOrExercisePrice>
                <value>2.54</value>
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            <transactionDate>
                <value>2018-08-24</value>
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                <transactionFormType>4</transactionFormType>
                <transactionCode>M</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F5"/>
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            <transactionAmounts>
                <transactionShares>
                    <value>131250</value>
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                <transactionAcquiredDisposedCode>
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                <footnoteId id="F2"/>
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            <expirationDate>
                <value>2026-02-11</value>
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                </natureOfOwnership>
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        <derivativeTransaction>
            <securityTitle>
                <value>Stock Option (Right to Buy)</value>
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                <transactionFormType>4</transactionFormType>
                <transactionCode>M</transactionCode>
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                <transactionShares>
                    <value>112500</value>
                </transactionShares>
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                    <value>D</value>
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            <exerciseDate>
                <footnoteId id="F3"/>
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            <expirationDate>
                <value>2027-02-09</value>
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                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
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        </derivativeTransaction>
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                    <value>37500</value>
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                    <value>0</value>
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                    <value>D</value>
                </transactionAcquiredDisposedCode>
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            <exerciseDate>
                <footnoteId id="F4"/>
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            <expirationDate>
                <value>2028-01-31</value>
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                <underlyingSecurityTitle>
                    <value>Common Stock</value>
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                <natureOfOwnership>
                    <value></value>
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            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">Option was fully vested.</footnote>
        <footnote id="F2">This option vests in a series of 48 consecutive equal monthly installments commencing February 11, 2016, provided the optionee continues to provide services to the Company.</footnote>
        <footnote id="F3">This option vests in a series of 48 consecutive equal monthly installments commencing February 9, 2017, provided the optionee continues to provide services to the Company.</footnote>
        <footnote id="F4">This option vests in a series of 48 consecutive equal monthly installments commencing January 31, 2018, provided the optionee continues to provide services to the Company.</footnote>
        <footnote id="F5">This transaction was conducted pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on July 13, 2018.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Olivia K. Bloom for Stephen N. Rosenfield</signatureName>
        <signatureDate>2018-08-24</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
