Hi Nick,
Thank you for reaching out. You can refer to
this support document to read about the requirements for using Customer Match. For additional information on requirements, you can also take a look at
this blog post.
As for your second question, yes, it is possible to build an audience based on an offline conversion event. As mentioned in
this documentation, you can have a
basic_user_list that targets a specific conversion type. For more details, you can refer to
this guide.
Regards,
Danica, Google Ads API Team

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