US Patent 11045005 Stackable active seat

An active seat includes a seat disposed at a first end of a body; a convex surface disposed at a second end of the body; and a stacking notch defined at an intermediate location along the body. The convex surface defines at least a first rocking path about which the active seat tilts. The stacking notch defines a flat surface recessed laterally inwardly from an outer periphery of the body taken at the first and second ends.