Escalated to be one of the most collectible perpetual calendar chronograph amongst collectors’ circle in recent years, the now neo-vintage Patek Philippe reference 3970 inherited its classic stepped lug case from its elder sibling ref. 2499. Sized down to 36mm in diameter, it was a great step forward for the maison into the modern era. Still celebrating the design of pump chronograph pushers, Patek Philippe introduced a new dial configuration in a more legible manner with the “American Typewriter” typeface in 1986. A design debut within the reference, the ref. 3970 was introduced alongside with the ref. 3971, a snap on sapphire caseback version that displays its Lemania calibre in full glory.

With growing scholarship for the model, the ref. 3970 can now be divided into 4 series with the first series estimated with less than 100 examples (including ref. 3971) defined as the rarest one of all. In production from 1986 until 1988 in only yellow gold, the movement serial began with 875’000. Notably an example numbered 874’004 achieved the most recent world record of $416,000 USD sold at Phillips TOKI auction in 2024. An extremely rare find, within the said 100 examples of the first series combined, only a handful of 3971J have appeared in the market.

First series (1986 – 1988) – Features a solid snap back case for ref. 3970 and snap on sapphire caseback for ref. 3971, feuille hands and rectangular indexes. Only produced in yellow gold with an estimated 100 examples produced. (The present example)

Second series (1987 – 1990) – Features a solid screw back case “E – Etanche”, feuille hands and baton indexes. Hallmarks on the side of the lugs. Produced in all four case materials with an estimated 650 examples produced across all metals.

Third series (1989 – 1995) – Features a solid screw back case “E – Etanche” and an additional sapphire caseback, baton hands and lapidated indexes. Estimated 1,350 examples produced across all metals.

Fourth series (1994 – 2004) – Same configuration as the third series however there is a change in serial number ranges in the movement and case and from 1997 onwards it features deployant clasp. Estimated 2,000 examples produced across all four metals.

Well-preserved and kept in a private collection for 6 years since it has last appeared in the market, the present first series example also features the uber rare Italian calendar through its apertures, it is so far the only known example to have this feature. Confirmed by the Patek Philippe Extract from the archives, this example with a movement 875’078 from the first series batch was born in 1987.