Simon Property Group, Inc. is a Delaware corporation that operates as a self-administered and self-managed real estate investment trust, or REIT, under the Internal Revenue Code of 1986, as amended, or the Internal Revenue Code. REITs will generally not be liable for U.S. federal corporate income taxes as long as they distribute not less than 100% of their REIT taxable income. Simon Property Group, L.P. is our majority-owned Delaware partnership subsidiary that owns all of our real estate properties and other assets. Unless stated otherwise or the context otherwise requires, references to "Simon" mean Simon Property Group, Inc. and references to the "Operating Partnership" mean Simon Property Group, L.P. References to "we," "us" and "our" mean collectively Simon, the Operating Partnership and those entities/subsidiaries owned or controlled by Simon and/or the Operating Partnership. According to the Operating Partnership's partnership agreement, the Operating Partnership is required to pay all expenses of Simon.
We own, develop and manage premier shopping, dining, entertainment and mixed-use destinations, which consist primarily of malls, Premium Outlets®, and The Mills®. As of December 31, 2018, we owned or held an interest in 206 income‑producing properties in the United States, which consisted of 107 malls, 69 Premium Outlets, 14 Mills, four lifestyle centers, and 12 other retail properties in 37 states and Puerto Rico. In addition, we have redevelopment and expansion projects, including the addition of anchors, big box tenants, and restaurants, underway at several properties in the United States, Canada, Europe and Asia. Internationally, as of December 31, 2018, we had ownership interests in nine Premium Outlets in Japan, four Premium Outlets in South Korea, three Premium Outlets in Canada, two Premium Outlets in Malaysia, and one Premium Outlet in Mexico. We also own an interest in eight Designer Outlet properties in Europe, of which six properties are consolidated, and one Designer Outlet property in Canada. Of the eight properties in Europe, two are located in Italy, two are located in the Netherlands and one each is located in Austria, Germany, France and the United Kingdom. We also have three international outlet properties under development. As of December 31, 2018, we also owned a 21.3% equity stake in Klépierre SA, or Klépierre, a publicly traded, Paris‑based real estate company, which owns, or has an interest in, shopping centers located in 16 countries in Europe.
For a description of our operational strategies and developments in our business during 2018, see Item 7, “Management’s Discussion and Analysis of Financial Condition and Results of Operations” of this Form 10‑K.