US Patent 9693604 Article of footwear with inner and outer midsole layers

An article of footwear includes an outsole having a heel region, a midfoot region, and a forefoot region. An outer midsole layer is secured to the outsole and extends only over the heel region and at least some of the midfoot region. An inner midsole layer is supported by the outer midsole layer and the outsole without being fixed thereto, and extends over the heel region, the midfoot region, and the forefoot region. The outer midsole layer is configured to surround a periphery of the inner midsole layer at the heel region. The outsole may include lateral and medial arch portions for traction.