<SEC-DOCUMENT>0001415889-25-011967.txt : 20250505
<SEC-HEADER>0001415889-25-011967.hdr.sgml : 20250505
<ACCEPTANCE-DATETIME>20250505163746
ACCESSION NUMBER:		0001415889-25-011967
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20250501
FILED AS OF DATE:		20250505
DATE AS OF CHANGE:		20250505

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			DIORIO CHRIS PH.D.
		CENTRAL INDEX KEY:			0001677721
		ORGANIZATION NAME:           	

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-37824
		FILM NUMBER:		25913553

	MAIL ADDRESS:	
		STREET 1:		400 FAIRVIEW AVENUE NORTH
		STREET 2:		SUITE 1200
		CITY:			SEATTLE
		STATE:			WA
		ZIP:			98109

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			IMPINJ INC
		CENTRAL INDEX KEY:			0001114995
		STANDARD INDUSTRIAL CLASSIFICATION:	ELECTRONIC COMPONENTS, NEC [3679]
		ORGANIZATION NAME:           	04 Manufacturing
		EIN:				912041398
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		400 FAIRVIEW AVENUE NORTH
		STREET 2:		SUITE 1200
		CITY:			SEATTLE
		STATE:			WA
		ZIP:			98109
		BUSINESS PHONE:		206-517-5300

	MAIL ADDRESS:	
		STREET 1:		400 FAIRVIEW AVENUE NORTH
		STREET 2:		SUITE 1200
		CITY:			SEATTLE
		STATE:			WA
		ZIP:			98109
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>form4-05052025_080542.xml
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0508</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2025-05-01</periodOfReport>

    <issuer>
        <issuerCik>0001114995</issuerCik>
        <issuerName>IMPINJ INC</issuerName>
        <issuerTradingSymbol>PI</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001677721</rptOwnerCik>
            <rptOwnerName>DIORIO CHRIS PH.D.</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>400 FAIRVIEW AVENUE NORTH</rptOwnerStreet1>
            <rptOwnerStreet2>SUITE 1200</rptOwnerStreet2>
            <rptOwnerCity>SEATTLE</rptOwnerCity>
            <rptOwnerState>WA</rptOwnerState>
            <rptOwnerZipCode>98109</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>true</isDirector>
            <isOfficer>true</isOfficer>
            <isTenPercentOwner>false</isTenPercentOwner>
            <isOther>false</isOther>
            <officerTitle>CHIEF EXECUTIVE OFFICER</officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <aff10b5One>0</aff10b5One>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2025-05-01</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>J</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F1"/>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>288132</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>199362</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>by DFT L.L.C.</value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>362694</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">Distribution of shares of Common Stock held in a trust managed by an independent trustee for the benefit of the reporting person's descendants by DFT L.L.C. for no consideration. Following the transaction, the reporting person is no longer the beneficial owner of the shares of Common Stock.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ Yukio Morikubo, Attorney in fact for Chris Diorio</signatureName>
        <signatureDate>2025-05-05</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
