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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link="#0563C1" vlink="#954F72"><div class=WordSection1><p class=MsoNormal><span style='font-size:12.0pt;color:black'>Patrice-Emmanuel Schmitz referred me to this thought-provoking link:<o:p></o:p></span></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal style='margin-left:.5in'><a href="https://joinup.ec.europa.eu/community/eupl/news/meaning-%E2%80%9Ccopyleft%E2%80%9D-eupl">https://joinup.ec.europa.eu/community/eupl/news/meaning-%E2%80%9Ccopyleft%E2%80%9D-eupl</a><o:p></o:p></p><p class=MsoNormal><span style='font-size:12.0pt;color:black'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:12.0pt;color:black'>Can anyone here precisely identify the language in the GPL licenses that makes it "strong" rather than "weak" copyleft? And can anyone here identify anything in copyright law or cases that allow this distinction in the meaning of "derivative work"?<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:12.0pt;color:black'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:12.0pt;color:black'>/Larry<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:12.0pt;color:black'><o:p> </o:p></span></p></div></body></html>