<SUBMISSION>
<ACCESSION-NUMBER>0001039160-05-000025
<TYPE>4
<PUBLIC-DOCUMENT-COUNT>1
<PERIOD>20050328
<FILING-DATE>20050328
<DATE-OF-FILING-DATE-CHANGE>20050328
<ISSUER>
<COMPANY-DATA>
<CONFORMED-NAME>AEROGEN INC
<CIK>0001039160
<ASSIGNED-SIC>3841
<IRS-NUMBER>330488580
<STATE-OF-INCORPORATION>DE
<FISCAL-YEAR-END>1231
</COMPANY-DATA>
<BUSINESS-ADDRESS>
<STREET1>2071 STIERLIN COURT
<CITY>MOUNTAIN VIEW
<STATE>CA
<ZIP>94043
<PHONE>650 864-7300
</BUSINESS-ADDRESS>
<MAIL-ADDRESS>
<STREET1>2071 STIERLIN COURT
<CITY>MOUNTAIN VIEW
<STATE>CA
<ZIP>94043
</MAIL-ADDRESS>
</ISSUER>
<REPORTING-OWNER>
<OWNER-DATA>
<CONFORMED-NAME>SHAW JANE E
<CIK>0001188931
</OWNER-DATA>
<FILING-VALUES>
<FORM-TYPE>4
<ACT>34
<FILE-NUMBER>000-31913
<FILM-NUMBER>05707698
</FILING-VALUES>
<BUSINESS-ADDRESS>
<STREET1>2200 MISSION COLLEGE BLVD
<CITY>SANTA CLARA
<STATE>CA
<ZIP>95052
<PHONE>6508647300
</BUSINESS-ADDRESS>
<MAIL-ADDRESS>
<STREET1>2071 STIERLIN COURT
<CITY>MOUNTAIN VIEW
<STATE>CA
<ZIP>94043
</MAIL-ADDRESS>
</REPORTING-OWNER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>edgardoc.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
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    <periodOfReport>2005-03-28</periodOfReport>

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        <issuerName>AEROGEN INC</issuerName>
        <issuerTradingSymbol>AEGN</issuerTradingSymbol>
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            <rptOwnerName>SHAW JANE E</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>2071 STIERLIN COURT, SUITE 100</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>MT. VIEW</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>94043</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Chairman and CEO</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

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        <nonDerivativeHolding>
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                <value>Common Stock</value>
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                </sharesOwnedFollowingTransaction>
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            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>by Trust</value>
                    <footnoteId id="F2"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">Purchase pursuant to rule10b5-1(c)(1) under the Securities Exchange Act of 1934, as amended</footnote>
        <footnote id="F2">Includes 2,962 shares held in the name of Peter F. Carpenter and Jane Elizabeth Carpenter, Trustees of the Carpenter 1983 Family Trust and 9,523 shares held by the Carpenter 1983 Irrevocable Trust.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>Jane E. Shaw</signatureName>
        <signatureDate>2005-03-28</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SUBMISSION>
