One of the distinct features of the society of the Clans is that they have their own caste system. There are five castes:

There's also an equivalent of the outcastes - the Dark Caste.

The Warriors are the rulers of the Clan society. There are three subcastes for different types of fighting gear (BattleMechs, aerospace vehicles, Elementals and one hypothetical for protomechs?). There's also a distinct difference between the "trueborns" and "freeborns" (that is, the individuals bred through eugenics and the individuals bred through natural means) - the trueborns are often considered superior to freeborns.

Aside of the fact that the warriors are above others, the rest of the castes are more or less equal. The Laborer caste, responsible for physical work, is the most numerous. Technicians are responsible for care and feeding of war machines and other hardware, Scientists develop technology and oversee eugenics program, and Merchants manufacture and trade everyday goods, materials and tools.

The Warrior caste is also the only one to have surnames; the best of the trueborn warriors have a bloodname. The Scientist caste also has the notion of "labnames", but they are not officially used outside of the caste.