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            <identifier scheme="http://www.sec.gov/CIK">0001799448</identifier>
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            <startDate>2025-01-01</startDate>
            <endDate>2025-12-31</endDate>
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    <dei:DocumentType contextRef="P01_01_2025To12_31_2025" id="hidden164657242">DEF 14A</dei:DocumentType>
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    <dei:EntityRegistrantName contextRef="P01_01_2025To12_31_2025" id="ixv-5858">ALIGOS THERAPEUTICS, INC.</dei:EntityRegistrantName>
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    <ecd:AwardTmgMnpiDiscTextBlock contextRef="P01_01_2025To12_31_2025" id="ixv-2860">&lt;div style="margin-top:18pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman;font-weight:bold"&gt;&lt;div style="font-style:italic;display:inline;"&gt;Equity Grant Practices &lt;/div&gt;&lt;/div&gt;&lt;div style="margin-top:6pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman"&gt;We do not have a policy governing the timing of grants of stock options but, generally, we grant options at regularly scheduled compensation committee or board of director meetings. We do not grant equity awards in anticipation of the release of material nonpublic information or time the release of material nonpublic information for the purpose of affecting the value of executive compensation. &lt;/div&gt;&lt;div style="margin-top:12pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman"&gt;During 2025, we did not grant stock options, stock appreciation rights, or similar option-like instruments to our named executive officers during the four business days prior to or the one business day following the filing of our periodic reports or the filing or furnishing of a Form &lt;div style="white-space:nowrap;display:inline;"&gt;8-K&lt;/div&gt; that discloses material nonpublic information. &lt;/div&gt;</ecd:AwardTmgMnpiDiscTextBlock>
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