The Obatta Cluster was a region of space in the Gamma Quadrant, located near the Teplan system and the Jenkata Nebula. The cluster laid on a regular Jem'Hadar patrol route which also includes the Kendi system. (DS9: "The Quickening")
According to the Star Trek: Star Charts (pg. 75), the Obatta Cluster was located in non-aligned space, in the Gamma Quadrant.