The first Patek Philippe Perpetual Calendar Chronograph ref. 3970, originally sold in 1987, is set to be auctioned by Sotheby's in Geneva. This watch marks the end of the ref. 2499's production and the beginning of a new era for Patek Philippe chronographs, featuring the lowest-numbered Lemania-based movement used by the brand. It represents a significant piece in the transition of Patek Philippe's complicated wristwatches from niche items to staples in their Grand Complications collection.
- First numbered ref. 3970
- Sold January 14, 1987
- Movement no. 875’000
- Estimate: CHF 1 – 3 million (~US$1.2 – 3.6 million)
This ref. 3970 represents the transition from the Valjoux 72-based cal. 13-130 Q to the smaller, Lemania-based cal. CH 27-70 Q.
The movement features Patek Philippe's own coupling solution for the chronograph, pivoting the clutch lever around the chronograph driving wheel axis.
Decoration on early Lemania-era movements, like this one, shows inconsistency in bevelling and a variable number of sharp inner angles.
The dial is made of solid 18k gold with a grained, silver finish and distinctive lettering, though the minutes totaliser shows some oxidation.
Hallmarks on the case back suggest the watch has been polished, but the case lines remain sharp.
The watch comes with its original box and certificate of origin, which are considered important given its historical nature.
This example has previously sold at auction in 2005 and 2015.