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            <identifier scheme="http://www.sec.gov/CIK">0001855747</identifier>
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            <startDate>2025-01-01</startDate>
            <endDate>2025-12-31</endDate>
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    <dei:DocumentType contextRef="c-1" id="f-2">DEF 14A</dei:DocumentType>
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    <dei:EntityRegistrantName contextRef="c-1" id="f-1">BLEND LABS, INC.</dei:EntityRegistrantName>
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    <ecd:AwardTmgMnpiDiscTextBlock contextRef="c-1" id="f-7">&lt;div style="margin-top:12pt;text-align:justify"&gt;&lt;span style="background-color:#ffffff;color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%"&gt;We do not grant equity awards on a predetermined schedule, but typically approve equity awards at regularly scheduled meetings of our Compensation Committee during an open trading window. We have not granted, nor do we intend to grant, stock options in anticipation of the release of material, nonpublic information that is likely to result in changes to the price of our common stock, such as a significant positive or negative earnings announcement, and, we have not taken, nor do we intend to take, material nonpublic information into account when determining the timing or terms of stock options.  Similarly, we have not timed, nor do we intend to time, the release of material, nonpublic information for the purpose of affecting the value of executive compensation or for any other purpose.&lt;/span&gt;&lt;/div&gt;</ecd:AwardTmgMnpiDiscTextBlock>
    <ecd:AwardTmgMethodTextBlock contextRef="c-1" id="f-6">We do not grant equity awards on a predetermined schedule, but typically approve equity awards at regularly scheduled meetings of our Compensation Committee during an open trading window.</ecd:AwardTmgMethodTextBlock>
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