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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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<SEC-DOCUMENT>0001140361-11-004093.txt : 20110125
<SEC-HEADER>0001140361-11-004093.hdr.sgml : 20110125
<ACCEPTANCE-DATETIME>20110125161849
ACCESSION NUMBER:		0001140361-11-004093
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20110121
FILED AS OF DATE:		20110125
DATE AS OF CHANGE:		20110125

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Bender Ulf
		CENTRAL INDEX KEY:			0001494262

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-04217
		FILM NUMBER:		11546705

	MAIL ADDRESS:	
		STREET 1:		FRIED-EBERT-STRASSE 14A
		CITY:			WILLICH-NEERSEN
		STATE:			2M
		ZIP:			47877

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			ACETO CORP
		CENTRAL INDEX KEY:			0000002034
		STANDARD INDUSTRIAL CLASSIFICATION:	WHOLESALE-CHEMICALS & ALLIED PRODUCTS [5160]
		IRS NUMBER:				111720520
		STATE OF INCORPORATION:			NY
		FISCAL YEAR END:			0630

	BUSINESS ADDRESS:	
		STREET 1:		ONE HOLLOW LANE
		CITY:			LAKE SUCCESS
		STATE:			NY
		ZIP:			11042
		BUSINESS PHONE:		5166276000

	MAIL ADDRESS:	
		STREET 1:		ONE HOLLOW LANE
		CITY:			LAKE SUCCESS
		STATE:			NY
		ZIP:			11042

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	ACETO CHEMICAL CO INC
		DATE OF NAME CHANGE:	19851203
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>doc1.xml
<DESCRIPTION>FORM 4
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0303</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2011-01-21</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000002034</issuerCik>
        <issuerName>ACETO CORP</issuerName>
        <issuerTradingSymbol>ACET</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001494262</rptOwnerCik>
            <rptOwnerName>Bender Ulf</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>ONE HOLLOW LANE</rptOwnerStreet1>
            <rptOwnerStreet2>SUITE 201</rptOwnerStreet2>
            <rptOwnerCity>LAKE SUCCESS</rptOwnerCity>
            <rptOwnerState>NY</rptOwnerState>
            <rptOwnerZipCode>11042</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Managing Dir. Pharma Waldhof</officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable></nonDerivativeTable>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Restricted Stock Units</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <footnoteId id="F1"/>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2011-01-21</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>16</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F1"/>
            </exerciseDate>
            <expirationDate>
                <footnoteId id="F1"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>16</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>723</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">Dividend equivalents accrued as a result of a cash dividend paid on January 21, 2011. 2,000 Restricted Stock Units (&quot;RSU's&quot;) were granted on December 4, 2008 and vest one-third each year beginning on December 6, 2009. Each RSU represents the contingent right to receive one share of common stock upon vesting. Each RSU also accrues dividend equivalents on each date that Aceto pays a cash dividend to holders of common stock generally. RSU's attributable to such dividend equivalents are subject to the same terms and conditions as the RSU's to which such dividend equivalents relate.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Ulf Bender</signatureName>
        <signatureDate>2011-01-25</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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