Patek Philippe Perpetual Calendar ref. 3940R-011 — 18K Rose Gold, Caliber 240 Q (micro-rotor), circa 2001

Few modern references embody Patek Philippe’s renaissance in complicated watchmaking as clearly as the 3940. Introduced in 1985, in the wake of the Quartz Crisis, it marked a bold reaffirmation of mechanical mastery. Alongside the 3970, the 3940 reintroduced serially produced perpetual calendars to the catalog, combining an ultra-slim automatic micro-rotor movement with a newly engineered calendar module. The first 25 examples were delivered to Chronometrie Beyer for its 225th anniversary.

At its core lies the celebrated caliber 240 Q, a self-winding movement with a gold micro-rotor, perpetual calendar, moon-phase, leap-year, and 24-hour indications. Measuring just 3.88 mm in height, it enabled the elegant, svelte case profile that became the hallmark of the 3940.

The 3940 occupies a pivotal place in Patek’s perpetual calendar lineage. The maison introduced the first perpetual calendar wristwatch in 1925, followed by the first serially produced self-winding perpetual calendar in 1962 with the ref. 3448. The 3940 carried this legacy into the modern era with a wearable 36 mm case, a perfectly balanced dial, and the convenience of automatic winding, features that helped redefine Patek Philippe’s identity around refined, everyday complications.

Among the various metals offered, rose gold is significantly rarer than yellow gold, appearing later in the production run and in notably smaller numbers. This scarcity, combined with its warm tone, makes the 3940R one of the most desirable configurations for collectors today.

The present watch, ref. 3940R-011, features an 18k rose-gold case and is fitted with a leather strap and an 18k rose-gold deployant clasp. Both casebacks are included, an exhibition back and an additional solid back in 18k rose gold, consistent with Patek’s delivery for this generation.

Adding to its significance, this example was sold by Beyer Chronometrie in Zurich, accompanied by its Certificate of Origin dated 18 October 2001. It is offered with its original box and outer box, an additional leather strap with matching 18k rose-gold buckle and a Patek Philippe tie.

A rare rose-gold example of one of Patek Philippe’s most important modern references.