Special Restriction on Unique ship?

[SnakThree]

AFAIK those ships are unique, that is there is only 1 of each of them in existence.

The Persephone belongs to a player/modeller still active here.

The Emperor of Kusari owns the Satsuma - don't know if it has been destroyed leading to 4.86.

The Necrosis belonged to a terrorist who I think is dead in-rp, and the player gone.

I saw necrosis month ago or so in New York.

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