In the 25th century, a member of any species can be duplicated Some may be routinely copied: artificials are regularly built to spec, and within fine tolerances they are effectively clones of each other, be that simple copies of their runtime program for bodiless AIs, or everything except the serial number for automata. Fabricant lines may be replicated by AGIS if they are particularly effective. For the ultra rich, clonehood with Recap technology offers a route to immortality. And, whilst it has never been formally observed in the wild, rumours circulate on the shadow net about the existence of cloned mutants; a "never event" haunting corporate liability lawmakers across the system.
In order to ensure compliance with various ARC and UBC ordinance, all legal clones (with the exception of artificials) are required to have kill switches in a similar manner to fabricants: typically they are tiny explosive charges near the base of the skull, and able to be activated by a senior management member of the corporate cloning entity. Whenever a kill switch is used, a formal report must be written and a formal autopsy by a recognised coroner must be carried out.
Creating and maintaining a human clone is difficult in practice, requiring advanced technology that only the vast resources of a megacorporation can supply. In some instances, some intrepid, back-street scientists claim to have made clones in an extralegal capacity. These clones do not have kill switches, but if detected through DNA population sampling or routine checks, local and remote security forces are obligated to terminate the illegal clone with immediate effect. Harbouring a known illegal clone is a serious crime.
A legal clone can become illegal by "going rogue" - effectively, stealing themselves from their owner. Though the majority of these are terminated immediately via the kill switch mechanism, some have slipped through the net, having their kill switches deactivated or removed by dubious means. Assuming they survive the deactivation process, these clones forge their own identities, living in the shadows, or hiding in plain sight, forever captive to the knowledge their very existence is against solar law.