<SEC-DOCUMENT>0001228924-17-000005.txt : 20170221
<SEC-HEADER>0001228924-17-000005.hdr.sgml : 20170221
<ACCEPTANCE-DATETIME>20170221192419
ACCESSION NUMBER:		0001228924-17-000005
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20170217
FILED AS OF DATE:		20170221
DATE AS OF CHANGE:		20170221

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			MESA LABORATORIES INC /CO
		CENTRAL INDEX KEY:			0000724004
		STANDARD INDUSTRIAL CLASSIFICATION:	INDUSTRIAL INSTRUMENTS FOR MEASUREMENT, DISPLAY, AND CONTROL [3823]
		IRS NUMBER:				840872291
		STATE OF INCORPORATION:			CO
		FISCAL YEAR END:			0331

	BUSINESS ADDRESS:	
		STREET 1:		12100 W 6TH AVE
		CITY:			LAKEWOOD
		STATE:			CO
		ZIP:			80228
		BUSINESS PHONE:		3039878000

	MAIL ADDRESS:	
		STREET 1:		12100 W 6TH AVE
		CITY:			LAKEWOOD
		STATE:			CO
		ZIP:			80228

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	MESA MEDICAL INC
		DATE OF NAME CHANGE:	19921123

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Sullivan John James
		CENTRAL INDEX KEY:			0001305784

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-11740
		FILM NUMBER:		17626675

	MAIL ADDRESS:	
		STREET 1:		12100 W. 6TH AVENUE
		CITY:			LAKEWOOD
		STATE:			CO
		ZIP:			80228

	FORMER NAME:	
		FORMER CONFORMED NAME:	Sullivan John J
		DATE OF NAME CHANGE:	20041013
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
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<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
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        <issuerName>MESA LABORATORIES INC /CO</issuerName>
        <issuerTradingSymbol>MLAB</issuerTradingSymbol>
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            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>LAKEWOOD</rptOwnerCity>
            <rptOwnerState>CO</rptOwnerState>
            <rptOwnerZipCode>80228</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
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        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>President and CEO</officerTitle>
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        </nonDerivativeTransaction>
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    <derivativeTable>
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            </securityTitle>
            <conversionOrExercisePrice>
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            <transactionDate>
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            <expirationDate>
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    <ownerSignature>
        <signatureName>John J Sullivan</signatureName>
        <signatureDate>2017-02-21</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
