> Therefore if a person doesn't want to be prospected, all she needs to do is erase her data from these public data sources. That seems to transfer the burden

> Therefore if a person doesn't want to be prospected, all she needs to do is erase her data from these public data sources. That seems to transfer the burden on to the recipient - basically, it seems to exploit an externality. Can you think of a better approach that more actively incorporates recipients’ preferences?