Patek Philippe SA is a Swiss luxury watch and clock manufacturer founded in 1839. Since 1932, it has been owned by the Stern family in Switzerland and remains the last family-owned independent watch manufacturer in Geneva. Patek Philippe is one of the oldest watch manufacturers in the world with an uninterrupted watchmaking history since its founding. It designs and manufactures timepieces as well as movements, including some of the most complicated mechanical watches. The company maintains over 400 retail locations globally and over a dozen distribution centers across Asia, Europe, North America, and Oceania. In 2001, it opened the Patek Philippe Museum in Geneva. Over the years, notable Patek Philippe patrons and timepiece owners include Queen Victoria, Queen Elizabeth II, Princess Diana, Pope Pius IX, Marie Curie, Albert Einstein, John F. Kennedy, Nelson Mandela, Pablo Picasso, Pyotr Tchaikovsky, and Leo Tolstoy.