These are the relevant references from the Books where Possession is mentioned.
I make no pronouncements on these matters, but report them as I find them.
Arrive at your own conclusions.
I wish you well,
"I was her master," I said. "It has been a long time. By now she may have fallen to another. Lapses have occurred. Who knows what collar is now on her neck. She may be a camp slave, a paga girl, a field slave, a caged brothel slut. Others may now have as much claim on her as I." Possession, particularly after a lengthy interval, is often regarded as decisive, by praetors, archons, magistrates, scribes of the law, and such. What is of most importance to the law is not so much that a particular individual owns a slave as that she is owned by someone, that she is absolutely and perfectly owned. It is the same with a kaiila, a verr, a tarsk, and such.
For all practical purposes, there is no escape for the Gorean slave girl. There is nowhere to run. Society wants them in their collars, and will see to it that they stay in them. If, as might happen in some hundreds of times, she might manage to elude one master, she would soon fall into the possession of another, and, as a runaway, would be subjected to a far more onerous bondage than that from which she fled. And, interestingly, they find their true self in the collar. They have an identity and fulfillment denied to the free woman. To know that they are slaves and will remain slaves unless freed, is for them a reassurance and comfort. It is said that all women are slaves, only that some are fortunate enough to be in collars and others not.