publication of the twice-a-year Patek Philippe Magazine in 1996, which is reserved for the watch owners and has received contributions from various prominent writers including Nobel Laureates Gao Xingjian and José Saramago. And in 2009, Philippe Stern's son, Thierry Stern, took over the reins from his father. In 2010, the company produced 40,000 timepieces and, according to Thierry Stern, it produced 58,000 pieces in 2017. In 2018, the number went up to 62,000, and in order to maintain quality and exclusivity, Patek Philippe would only slowly increase the number of timepieces produced each year (by 1-3 percent per year) but with a ceiling. Currently, the company is an active member of the Federation of the Swiss Watch Industry FH. Since 2000s, Patek Philippe timepieces have repeatedly fetched high prices in auctions worldwide. As of 2018, among the world's top ten most expensive watches ever sold at auctions, seven are Patek Philippe watches. Among the top 58 most expensive watches sold at auction (over 2 million US dollars), 46 are Patek Philippe watches. A small part of the demand for auction pieces is driven by Patek Philippe themselves, as they are purchasing in the auction market to add to the collection of the Patek Philippe Museum in Geneva. Motto and slogan One of Patek Philippe's company slogans is "You never actually own a Patek Philippe. You merely look after it for the next generation." The slogan was introduced when the company launched its "Generations" campaign in 1996. Watch manufacturing Patek Philippe manufactures its own watch components. Like other Swiss manufacturers, the company produces mostly mechanical movements with automatic or manual winding mechanism, but has also been producing quartz watches. In fact, Patek Philippe was one of the twenty Swiss watch companies that founded the Centre Electronique Horloger and collaboratively developed the first Swiss quartz movements, such as the Beta 21 movement (1969) which was used by several manufacturers in their watches. In 1950s, the company even produced a prototype for a mechanical digital wristwatch, Ref. 3414. Patek Philippe popularized complications such as perpetual calendar, split-seconds hand, chronograph, and minute repeater in mechanical watches. In 2009, the company announced that all of its future mechanical timepieces would be imprinted with the Patek Philippe Seal which requires a precision of -3/+2 seconds per day for diameters no less than 20 mm and -5/+4 seconds per day for diameters less than 20 mm, surpassing