Even if they wipe it in recovery mode the phone will still be bound to the owners iCloud account. Once they get to the activation screen the phone will contact Apple and then display a prompt to enter the iCloud password to proceed with the setup.
The phone will either need to be released by the iCloud owner or they will need to contact Apple support and provide a proof of purchase receipt.
lastemperor86 t1_j6cf0t2 wrote
Reply to Can someone erase my iPhone completely if it’s stolen? by findthemistke
Even if they wipe it in recovery mode the phone will still be bound to the owners iCloud account. Once they get to the activation screen the phone will contact Apple and then display a prompt to enter the iCloud password to proceed with the setup. The phone will either need to be released by the iCloud owner or they will need to contact Apple support and provide a proof of purchase receipt.