The Patek Philippe reference 5140 is one of the most elegant perpetual calendar wristwatches in the manufacture's modern collection, combining timeless dress-watch proportions with one of Patek Philippe's most celebrated complications. Introduced in 2006 as the successor to the reference 3940, the 5140 is powered by the ultra-thin automatic Calibre 240 Q, renowned for its micro-rotor construction, exceptional finishing and long-standing reliability. Its beautifully balanced dial features the classic perpetual calendar layout, displaying the day, date, month, leap year indication, 24-hour display and moon phase, offering remarkable mechanical complexity within a refined and highly legible design. Produced in yellow gold, white gold, rose gold and platinum, the 5140 has become one of the defining perpetual calendar references of the modern era, admired for its understated elegance, technical excellence and faithful continuation of Patek Philippe's tradition of classical haute horlogerie.