Reference 3970 is a collector classic reigning from the legendary Patek Philippe Perpetual Calendar Chronograph family that began with Reference 1518 in 1941. Originally launched in 1986 to replace Reference 2499, the timepiece features a Lemania-based movement rather than the prior Valjoux-based movement. The present lot is crafted from 18k white gold and is housed in a classically sized 36mm case. The timepiece has a silver dial with applied white gold hour markers and hands.

As part of the fourth series of 3970s (1994-2004), the present lot which was purchased in 2003 represents one of the last 3970s before successor Reference 5970 came in production in 2004. Within the fourth series, white gold examples are among the rarest and most desirable by collectors.