Patek Philippe

Part of the iconic and hugely important perpetual calendar chronograph lineage of Patek Philippe, reference 3970 was launched in 1986 as the replacement for the iconic reference 2499 and occupies a position of enormous importance within the history of modern complicated Patek Philippe wristwatches. It is widely regarded as the reference that launched the modern era of the brand’s grand complications. While maintaining the signature aesthetic established by references 1518 and 2499, the reference 3970 utilized a Lemania-based ébauche rather than the earlier Valjoux movement and introduced both leap year and 24-hour indications for the first time.

The reference was produced in yellow gold, pink gold, white gold, and platinum across a total of four series, with production spanning approximately 19 years, and can be broken down as such:

First series (1986–1988): Snap-back case, feuille hands, and rectangular hour indexes. Produced only in yellow gold, with approximately 100 examples made.

Second series (1987–1990): Solid screw-back case (“E – Étanche”), feuille hands, and baton indexes. Produced across all four metals, with roughly 450 examples in total.

Third series (1989–1995): Solid screw-back case (“E – Étanche”) with an additional sapphire display back, baton hands, and faceted (lapidated) hour markers. Approximately 1,350 examples produced across all metals.

Fourth series (1994–2004): Maintains the configuration of the third series, though the movement and case serial ranges changed. From 1997 onward, a deployant clasp was introduced. Approximately 2,000 examples are believed to have been produced.

Today, the ref. 3970 is increasingly appreciated not only for its technical significance, but also for representing the last generation of classically proportioned perpetual calendar chronographs before the modern era of larger complicated wristwatches. Indeed, succeeding references have all been north of 40mm in diameter. The present example belongs to the coveted second series, featuring baton indexes and leaf-shaped hands. The reference is designated “3970E” on the Extract from the Archives, the “E” standing for étanche, French for waterproof. This represented an upgrade over the first series, which featured snap-on case backs, with the second series introducing screw-down backs for improved water resistance. Some examples, such as the present watch, were furthermore delivered with an additional sapphire crystal display back. The current watch is accompanied by its box and is presented in excellent condition, retaining crisp oversized hallmarks to the side of the lugs and on the pin buckle.