<SEC-DOCUMENT>0001415889-25-022639.txt : 20250821
<SEC-HEADER>0001415889-25-022639.hdr.sgml : 20250821
<ACCEPTANCE-DATETIME>20250821174441
ACCESSION NUMBER:		0001415889-25-022639
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20250820
FILED AS OF DATE:		20250821
DATE AS OF CHANGE:		20250821

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:		251241806

	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>form4-08212025_090833.xml
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0508</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2025-08-20</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></nonDerivativeTable>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Restricted Stock Units</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>0</value>
                <footnoteId id="F1"/>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2025-08-20</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>15015</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F2"/>
            </exerciseDate>
            <expirationDate>
                <footnoteId id="F2"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>15015</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>15015</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">Each RSU represents a contingent right to receive one share of Impinj common stock.</footnote>
        <footnote id="F2">One-fourth of the shares subject to the grant shall vest on August 20, 2026, and 1/16th of the shares subject to the grant shall vest each quarter thereafter, subject to the reporting person's continued service to the Issuer through such date.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ Yukio Morikubo, Attorney in fact for Chris Diorio</signatureName>
        <signatureDate>2025-08-21</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
