Along with the Darkvenge, the Keeper served as one of a pair of Lucrehulk-class battleships that comprised the Trade Federation's Special Task Force One.
During 27 BBY, Thrawn annihilated it, along with the majority of the task force.
A mistake occurs in Outbound Flight; specifically, in chapter 16 on page 270 of the hardcover version, Siv Kav erroneously refers to the Keeper as the Seeker.