Another memorable entry in Patek Philippe’s lineup of perpetual calendar watches is the Ref. 3940 from 1985. The watch was famously powered by the caliber 240 & PQ self-winding movement, which is also one of the thinnest movements in the world. This was a truly refined timepiece that obviously came from a truly refined brand.
More than that, however, the Ref. 3940 also marked a defining moment for Patek Philippe. The watch was launched in the midst of the quartz crisis, when few—if any—watches with complications were being produced. Still, Philippe Stern, Father of current CEO Thierry Stern, stood by his vision to develop a complicated mechanical watch with an extra-thin movement. The result of this initiative, the caliber 240, was launched in 1977 for the