-----BEGIN PRIVACY-ENHANCED MESSAGE-----
Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
Originator-Key-Asymmetric:
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 TWSM7vrzLADbmYQaionwg5sDW3P6oaM5D3tdezXMm7z1T+B+twIDAQAB
MIC-Info: RSA-MD5,RSA,
 CRnpxQOrMbm0hcO5T1bDAe5rheHlQyek2fBwlPMivp7NgU4ZZetX4gDnSFfq+5nm
 4qX1o7DZN5yLdYTTuLaenw==

<SEC-DOCUMENT>0001031833-08-000050.txt : 20080501
<SEC-HEADER>0001031833-08-000050.hdr.sgml : 20080501
<ACCEPTANCE-DATETIME>20080501185506
ACCESSION NUMBER:		0001031833-08-000050
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20080501
FILED AS OF DATE:		20080501
DATE AS OF CHANGE:		20080501

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			SPACEDEV, INC.
		CENTRAL INDEX KEY:			0001031833
		STANDARD INDUSTRIAL CLASSIFICATION:	GUIDED MISSILES & SPACE VEHICLES & PARTS [3760]
		IRS NUMBER:				841374613
		STATE OF INCORPORATION:			CO
		FISCAL YEAR END:			1109

	BUSINESS ADDRESS:	
		STREET 1:		13855 STOWE DRIVE
		STREET 2:		PO BOX 2121
		CITY:			POWAY
		STATE:			CA
		ZIP:			92064
		BUSINESS PHONE:		8583752000

	MAIL ADDRESS:	
		STREET 1:		13855 STOWE DRIVE
		CITY:			POWAY
		STATE:			CA
		ZIP:			92064

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	SPACEDEV INC
		DATE OF NAME CHANGE:	19991118

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	PEGASUS DEVELOPMENT GROUP INC
		DATE OF NAME CHANGE:	19980605

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			ESTES HOWELL M
		CENTRAL INDEX KEY:			0001138355

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-28947
		FILM NUMBER:		08796174

	BUSINESS ADDRESS:	
		BUSINESS PHONE:		858-375-2000

	MAIL ADDRESS:	
		STREET 1:		13855 STOWE DR.
		CITY:			POWAY
		STATE:			CA
		ZIP:			92604
</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>2008-05-01</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001031833</issuerCik>
        <issuerName>SPACEDEV, INC.</issuerName>
        <issuerTradingSymbol>SPDV</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001138355</rptOwnerCik>
            <rptOwnerName>ESTES HOWELL M</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>13855 STOWE DR.</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>POWAY</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>92604</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>COMMON STOCK</value>
            </securityTitle>
            <transactionDate>
                <value>2008-05-01</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>M</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>1177</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0.52</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>67844</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>NON STATUTORY STOCK OPTION</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>0.52</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2008-05-01</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>M</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>5000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0.52</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <value>2004-05-06</value>
            </exerciseDate>
            <expirationDate>
                <value>2008-05-06</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>COMMON STOCK</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>5000</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>95500</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <ownerSignature>
        <signatureName>HOWELL M. ESTES, III</signatureName>
        <signatureDate>2008-05-01</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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