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        <entity>
            <identifier scheme="http://www.sec.gov/CIK">0001835579</identifier>
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        <period>
            <startDate>2026-08-04</startDate>
            <endDate>2026-08-04</endDate>
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    <context id="offrl_1">
        <entity>
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            <startDate>2026-08-04</startDate>
            <endDate>2026-08-04</endDate>
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    <unit id="USD">
        <measure>iso4217:USD</measure>
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    <unit id="pure">
        <measure>pure</measure>
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    <unit id="Shares">
        <measure>shares</measure>
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    <ffd:FormTp contextRef="rc" id="ixv-168">S-8</ffd:FormTp>
    <ffd:SubmissnTp contextRef="rc" id="ixv-169">S-8</ffd:SubmissnTp>
    <ffd:FeeExhibitTp contextRef="rc" id="ixv-170">EX-FILING FEES</ffd:FeeExhibitTp>
    <dei:EntityCentralIndexKey contextRef="rc" id="ixv-171">0001835579</dei:EntityCentralIndexKey>
    <dei:EntityRegistrantName contextRef="rc" id="ixv-172">ImageneBio, Inc.</dei:EntityRegistrantName>
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    <dei:EntityRegistrantName contextRef="rc" id="ixv-201">ImageneBio, Inc.</dei:EntityRegistrantName>
    <ffd:OfferingSctyTp contextRef="offrl_1" id="ixv-202">Equity</ffd:OfferingSctyTp>
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      contextRef="offrl_1"
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      unitRef="USD">5.57</ffd:MaxOfferingPricPerScty>
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      contextRef="offrl_1"
      decimals="2"
      id="ixv-207"
      unitRef="USD">4734500.00</ffd:MaxAggtOfferingPric>
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      contextRef="offrl_1"
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      id="ixv-208"
      unitRef="pure">0.0001381</ffd:FeeRate>
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      contextRef="offrl_1"
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      id="ixv-209"
      unitRef="USD">653.83</ffd:FeeAmt>
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    <ffd:TtlOffsetAmt contextRef="rc" decimals="2" id="ixv-212" unitRef="USD">0.00</ffd:TtlOffsetAmt>
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    <ffd:OfferingNote contextRef="offrl_1" id="ixv-214">The amount registered represents additional shares of ImageneBio, Inc.'s (the "Registrant's") common stock, par value $0.001 per share (the "Common Stock"), authorized for issuance under the Registrant's Amended and Restated 2025 Equity Incentive Plan (the "2025 Plan"), which additional shares were approved by the Registrant's stockholders at the Registrant's annual meeting of stockholders held on June 16, 2026. Pursuant to Rule 416(a) under the Securities Act of 1933, as amended (the "Securities Act"), the Registration Statement on Form S-8 to which this exhibit is a part (the "Registration Statement") shall also cover any additional shares of Common Stock that become issuable under the 2025 Plan by reason of any stock dividend, stock split, recapitalization or other similar transaction. The proposed maximum aggregate offering price per unit and proposed maximum aggregate offering price is estimated in accordance with Rule 457(h)(1) and Rule 457(c) of the Securities Act solely for purposes of calculating the registration fee, and are based upon the average of the high and low prices of the Common Stock on July 31, 2026, as reported on the Nasdaq Capital Market. </ffd:OfferingNote>
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