Pre-Upheaval independent organization controlling a planetary surveillance network that predates the faction structure. Acquisition Teams recover archived material. The Seat has never been photographed.
Halcyon predates the factions. The surveillance network they maintain was built before the Upheaval, for purposes that remain undocumented. The Seat — three to five individuals who have never been photographed together — directs Acquisition Teams to recover pre-Upheaval material on contract.
The Brokers are the public face: information traders operating in neutral cities. The Keepers are rumored analysts. The network itself is older than any active faction and has survived every attempt to map it. CHORUS_ZERO is a Halcyon data core. The Null Chorus doesn't know that yet.