The topic of Castes would not be complete without also including Clans.
Here are relevant references from the Books where Clans in general are mentioned.
I make no pronouncements on these matters, but report them as I find them.
Arrive at your own conclusions.
I wish you well,
"You must learn," Torm had said matter-of-factly, "the history and legends of Gor, its geography and economics, its social structures and customs, such as the caste system and clan groups, the right of placing the Home Stone, the Places of Sanctuary, when quarter is and is not permitted in war, and so on."
Tarnsman of Gor Book 1 Page 40
The tarn is one of the two most common mounts of a Gorean warrior; the other is the high tharlarion, a species of saddle-lizard, used mostly by clans who have never mastered tarns.
Tarnsman of Gor Book 1 Page 52
"May the Priest-Kings blast your bones," I shouted, as cheerfully as I could, adding, for good measure, "and may you thrive upon the excrement of tharlarions!" The latter recommendation, with its allusion to the loathed riding lizards used by many of the primitive clans of Gor, seemed to please him.
Tarnsman of Gor Book 1 Page 78
I crossed the Cartius on a barge, one of several hired by the merchant of the caravan with which I was then serving. These barges, constructed of layered timbers of Ka-la-na wood, are towed by teams of river tharlarion, domesticated, vast, herbivorous, web-footed lizards raised and driven by the Cartius bargemen, fathers and sons, interrelated clans, claiming the status of a caste for themselves.
Nomads of Gor Book 4 Pages 3 - 4
The Wagon Peoples, as might be expected, have a large and complex oral literature. This is kept by and occasionally, in parts, recited by the Camp Singers. They do not have castes, as Goreans tend to think of them. For example, every male of the Wagon Peoples is expected to be a warrior, to be able to ride, to be able to hunt, to care for the bosk, and so on. When I speak of Year Keepers and Singers it must be understood that these are not, for the Wagon Peoples, castes, but more like roles, subsidiary to their main functions, which are those of the war, herding and the hunt. They do have, however, certain clans, not castes, which specialize in certain matters, for example, the clan of healers, leather workers, salt hunters, and so on. I have already mentioned the clan of torturers. The members of these clans, however, like the Year Keepers and Singers, are all expected, first and foremost, to be, as it is said, of the wagons namely to follow, tend and protect the bosk, to be superb in the saddle, and to be skilled with the weapons of both the hunt and war.
Nomads of Gor Book 4 Page 12
Goreans do not generally favor begging, and some regard it as an insult that there should be such, an insult to them and their city. When charity is in order, as when a man cannot work or a woman is alone, usually such is arranged through the caste organization, but sometimes through the clan, which is not specifically caste oriented but depends on ties of blood through the fifth degree. If one, of course, finds oneself in effect without caste or clan, as was perhaps the ease with the small fool named Hup, and one cannot work, one's life is likely to be miserable and not of great length.
Assassin of Gor Book 5 Pages 11 - 12
The Players are not a caste, nor a clan, but they tend to be a group apart, living their own lives.
Assassin of Gor Book 5 Page 27
It was the next day, at the eleventh Ahn, one Ahn past the Gorean noon, that we arrived at the Oasis of Red Rock.
It was dominated by the kasbah of its pasha, Turem a'Din, commander of the local Tashid clans, on its rim to the northeast.
Tribesmen of Gor Book 10 Page 175
The clan structures are kinship groups. They function, on the whole, given mating practices, within the caste structure, but they are not identical to it. For example, in a given clan there may be, though often are not, individuals of different castes. Many Goreans think of the clan as a kinship group within a caste. For most practical purposes they are correct. At least it seldom does much harm to regard the matter this way. Clans, because of practical limitations on mobility, are usually associated, substantially, with a given city; the caste, on the other hand, is transmunicipal or intermunicipal.
Slave Girl of Gor Book 11 Page 213
The status of being a public slave tends to be an ambiguous one. What is a girl to do, how is she to act, to whom is she to relate? In such a status she is an impersonal property, as of a state, clan or tribe.
Blood Brothers of Gor Book 18 Page 450
"Your name, 'Emily,' is very beautiful," he said. "As you probably know, it is a barbarian corruption of my gens, name. It seems that fate has thrown us together." The gens name is the clan name.
Kajira of Gor Book 19 Page 276
Caste is extremely important to most Goreans, even when they do not all practice the traditional crafts of their caste. It is one of the "nationalities" of the Gorean, so to speak. Other common "nationalities," so to speak, are membership in a kinship organization, such as a clan, or phratry, a group of clans, or a larger grouping yet, a tribe or analogous to a tribe, a group of phratries, and a pledged allegiance to a Home Stone, usually that of a village, town or city.
Dancer of Gor Book 22 Page 293
Too, he was not Gorean. He knew not the ways of Gor. He had no clan, no caste, no Home Stone.
Swordsmen of Gor Book 29 Page 167
Charity, care of the simple, the needy, and such, is handled privately, usually by clan lines, or caste councils.
Conspirators of Gor Book 31 Page 100
Master Grendel, as the Lady Bina apparently was not was well aware of the possible jeopardy in which an unguarded free woman might find herself on Gor. Too, she had no Home Stone, no family, no clan, no caste.
Conspirators of Gor Book 31 Page 232