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<!-- Generated by Broadridge Transform (tm) - http://www.broadridge.com -->
<!-- Created: Fri Jun 26 21:16:20 UTC 2026 -->
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  <definitionLink xlink:role="http://xbrl.sec.gov/vip/role/PortfolioCompanyOnly" xlink:type="extended">
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    <loc xlink:type="locator" xlink:label="cik0001048606_PutnamVTUSResearchFundClassIBMember" xlink:href="cik0001048606-20260626.xsd#cik0001048606_PutnamVTUSResearchFundClassIBMember"/>
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