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<p class="MsoNormal">Hi Folks,<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">For PTR records out there that are pointing to domains other than those that you control, I’m looking to understand common practice around their setup. Two questions:<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoListParagraph" style="text-indent:-18.0pt;mso-list:l0 level1 lfo2"><![if !supportLists]><span style="mso-list:Ignore">1.<span style="font:7.0pt "Times New Roman"">
</span></span><![endif]>In general, can I trust PTR records? Is ownership of the target domain validated at setup time by ISPs, and if yes, how is this done?<o:p></o:p></p>
<p class="MsoListParagraph" style="text-indent:-18.0pt;mso-list:l0 level1 lfo2"><![if !supportLists]><span style="mso-list:Ignore">2.<span style="font:7.0pt "Times New Roman"">
</span></span><![endif]>If ownership of PTR targets is not routinely validated, is there a risk that the target domain could be blacklisted by anti-spam providers?<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Thanks,<o:p></o:p></p>
<p class="MsoNormal">Stephen Malone<o:p></o:p></p>
<p class="MsoNormal">Microsoft<o:p></o:p></p>
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