Abstract: We present a representation of an axis-aligned bounding volume hierarchy (BVH) for ray tracing that removes redundant bounding information from the data structure. The observation that two children of a binary BVH node share at least six planes with their parent node leads to two possible optimizations: (a) the size of the data structure can be optimized by storing six floats instead of 12 for the bounds of the two children, and (b) the box-intersection code can be optimized by avoiding the reintersection with shared planes. These optimizations reduce memory consumption of the hierarchy by 37.5 percent with only a marginal impact on ray-shooting performance.