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SIM "cloning" is not possible because the key stored in the SIM card cannot be read. Instead, forensic investigators use a technique called "SIM spoofing" to make a blank SIM card appear as if it's the original one, but it can't register on the network or make calls. The article suggests that the only realistic way to achieve multiple devices with the same number is to have separate accounts for each device. One possible workaround is using Google Voice and Fi carrier service, but this requires a primary SIM card and a data-only SIM card, which may not be available from all carriers.