Patek Philippe ref. 3970P Perpetual Calendar Chronograph Platinum Second Series Review

For watch collectors, Patek Philippe is a name that is synonymous with perpetual calendar chronographs. They were the trailblazers of serial production of the complication and created the first serially produced model when they introduced the 1518 in 1941. The follow-up, ref. 2499, was released just ten years later in 1951. Each reference was made in small amounts, with only 281 examples of the 1518 and 349 of the 2499. As a consequence, they are among the most coveted vintage watches ever made. 

But Patek didn’t stop there. In 1986, they introduced the 3970, the first perpetual calendar chronograph that they truly produced at scale. From 1986 to 2004, roughly 4,000 examples of ref. 3970 were produced, the first series of which was the immediate successor to the 2499. The second series was the first to feature a screw down caseback for increased water resistance.

This example, a ref. 3970P Perpetual Calendar Chronograph in platinum, is one of the approximately 650 pieces produced in the second series. Only a small fraction of the second series run of ref. 3970 were produced in a 36mm platinum case, making it one of the rarest iterations.

This particular example of the ref. 3970 is in pristine condition, with its hallmarks crisp and intact on the strong lugs. The pure opaline dial complements the colder tone of the platinum case brilliantly, contrasting tastefully with the deep blue moonphase at the six o’clock position. It’s powered by Patek Philippe’s Caliber CH 27-70Q, a three-subdial split-seconds perpetual calendar chronograph, which is based on the legendary Lemania 2310. 

The ref. 3970 represents a key inflection point in Patek Philippe’s transition from a manufacturer with small outputs to a prolific luxury watchmaking powerhouse. Rare, significant pieces of history like the Patek Philippe 3970 are getting harder and harder to find. This piece, with its elusive and desirable platinum case, serves as testimony to Patek’s unrivaled legacy of complicated movement construction and excellence in fine watchmaking .