A powerful Orion and Andorian criminal syndicate that dominated trade in the 32nd century after the Burn.
The Emerald Chain is a crime syndicate formed by Orions and Andorians that seized control of trade and dilithium after the Burn left the Federation weakened. It relies on force and slave labour, and becomes the main rival of the Federation in Discovery's third season.
Its leader Osyraa seizes the USS Discovery in There Is a Tide..., aided by the Chain's scientist Aurellio. Michael Burnham and Cleveland Booker help defeat her, and the syndicate begins to collapse after her death.