“Cognomen” data-wafer is the official Administratum designation in the Imperium for a citizen’s identity card. In a hive, it is one of the only viable means of tracking, taxing and identifying the citizenry. Cognomen are usually blank iron-grey, punched-metal squares (about the size and shape of a Imperial tarot card) and designed to be read by data-slates and cogitator systems. The only feature on the face of a Cognomen is the symbol of the issuing habitat, guild or Adepta whom the citizen serves. In some ways, ownership of a cognomen is frighteningly important: it represents the only legal proof of identity, a right to work and even to be fed and housed for the average citizen. Its loss might genuinely mean starvation, abandonment, arrest or even being cast down into the fringes in the blind face of Imperial bureaucracy. There is, of course, a thriving trade in the theft and falsification of cognomen, the price for a “face” varies on the identity fabricated or stolen, and can range from a few eaglesto thousands
Lost Cognomen may reapplied from Administratum, but if one does not have substantial funds for bribes or authority of an Imperial charter gaining the new Cognomen may take longer than citizens lifetime.
All children born to Imperial citizens in worlds under Imperial rule receive their Cognomen only after they are checked for mutations, have admitted a gene-print and have provided a negative psychic screening results at the age of 10. The age which is considered to be mature enough for a Imperial military conscription.
If neither of child’s parents are registered as an Imperial citizen child does not get Cognomen automatically and it must be applied from the Administratum, but if one does not have substantial funds for bribes or backing of a person of Imperial authority gaining the new Cognomen may take longer than citizens lifetime.
In the feudal Imperial societies only upper caste of the planet have a cognomen. In those planets a majority of population is classified as serfs, who do not have privileges of an Imperial citizen.
In the hive cities the lowest caste of the population, known as Dalits in high gothic or hive-scum in low gothic, constitutes from people and lineages, who have lost their Cognomens and cannot afford to apply new ones.