GS 12 was a starship that was registered for Federation travel in the late 24th century. In 2370, the captain of this ship was H. Ellison. The starship's point of departure was Organia. The starship arrived at Deep Space 9 on stardate 47557.1. The GS 12 was listed on the space station's arrival roster. (DS9: "Whispers", production art)
This starship was only mentioned in writing.