Clarus IX was a planet located somewhere in the space of the galaxy's Alpha or Beta Quadrants, the ninth planet in orbit of the Clarus star system.
History and specifics[]
In the year 2376, following his escape from Malic and the Orion Syndicate, Gaila asked Ro Laren and Quark to transport him to Clarus IX, rather than travel with them to Deep Space 9. Ro refused his request. (DS9 - Gateways novel: Demons of Air and Darkness)