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    <periodOfReport>2026-10-06</periodOfReport>

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    <issuer>
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        <issuerName>BIOLIFE SOLUTIONS INC</issuerName>
        <issuerTradingSymbol>BLFS</issuerTradingSymbol>
        <issuerForeignTradingSymbol></issuerForeignTradingSymbol>
    </issuer>

    <reportingOwner>
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            <rptOwnerName>Berard Todd</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerNonUSAddressFlag>false</rptOwnerNonUSAddressFlag>
            <rptOwnerStreet1>3303 MONTE VILLA PARKWAY</rptOwnerStreet1>
            <rptOwnerStreet2>SUITE 310</rptOwnerStreet2>
            <rptOwnerCity>BOTHELL</rptOwnerCity>
            <rptOwnerState>WA</rptOwnerState>
            <rptOwnerZipCode>98021</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
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            <isDirector>false</isDirector>
            <isOfficer>true</isOfficer>
            <isTenPercentOwner>false</isTenPercentOwner>
            <isOther>false</isOther>
            <officerTitle>Chief Marketing Officer</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <aff10b5One>false</aff10b5One>

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    <footnotes>
        <footnote id="F1">Reflects the disposition of shares of common stock (&quot;Common Stock&quot;) of BioLife Solutions, Inc. (the &quot;Registrant&quot;) in connection with the consummation on October 6, 2026 of the merger of Bravo Merger Sub I, Inc., a Delaware corporation (&quot;Merger Sub 1&quot;) with and into the Registrant (the &quot;First Merger&quot;), pursuant to the Agreement and Plan of Merger, dated as of July 21, 2026 (the &quot;Merger Agreement&quot;), by and among the Registrant, Repligen Corporation, a Delaware corporation (&quot;Repligen&quot;), Merger Sub 1 and Bravo Merger Sub II, LLC, a Delaware limited liability company. At the effective time of the First Merger (the &quot;First Merger Effective Time&quot;), each outstanding share of Common Stock was converted into the right to receive $11.25 in cash and 0.1442 shares of Repligen common stock, in each case subject to the terms and conditions of the Merger Agreement.</footnote>
        <footnote id="F2">The restricted stock was granted pursuant to the BioLife Solutions 2023 Omnibus Performance Incentive Plan (the &quot;2023 Plan&quot;). In accordance with the terms of the grant and the Merger Agreement, the restricted stock vested immediately prior to the First Merger Effective Time as to approximately 200% of the number of shares granted based on the Registrant's total shareholder return during the period beginning on January 1, 2025 through October 2, 2026 as compared to the total shareholder return of certain of the Registrant's peers (such peers have been determined by the Registrant's compensation committee with assistance of an outside consultant immediately prior to the grant date).</footnote>
        <footnote id="F3">The restricted stock was granted pursuant to the 2023 Plan. In accordance with the terms of the grant and the Merger Agreement, the restricted stock vested immediately prior to the First Merger Effective Time as to approximately 200% of the number of shares granted based on the Registrant's total shareholder return during the period beginning on January 1, 2026 through October 2, 2026 as compared to the total shareholder return of certain of the Registrant's peers (such peers have been determined by the Registrant's compensation committee with assistance of an outside consultant immediately prior to the grant date).</footnote>
        <footnote id="F4">Represents shares withheld to cover tax withholding obligations in connection with the vesting of the market-based restricted stock award.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ Todd Berard</signatureName>
        <signatureDate>2026-10-08</signatureDate>
    </ownerSignature>
</ownershipDocument>
