5370P, Split Seconds Chronograph, Platinum

The Patek Philippe ref. 5370 Split Seconds Chronograph, launched in 2015, marked the manufacture’s return to the pure split seconds—a complication it had not produced as a stand-alone, non-monopusher model since the mid 20th century. The project began shortly after Patek introduced its first in-house chronograph movement family (cal. CH 29-535) in 2009. Under Thierry Stern’s direction with movement development led by Philip Barat and case/dial design overseen by Sandrine Stern, the goal was to create a flagship rattrapante that combined pre-war Genevan aesthetics with contemporary mechanical rigor. The 5370P-001 debuted in this platinum with a grand feu black enamel dial, Breguet numerals, feuille hands, and sculpted lugs that helped define an instantly recognizable silhouette.

The story of its creation centers on Patek’s desire to demonstrate complete autonomy in chronograph construction. Unlike the split seconds chronographs of the 1990s–2000s, which relied on Nouvelle Lémania ébauches, the 5370 uses the fully in-house rattrapante calibre CHR 29-535 PS. This movement represented a major generational leap, incorporating six patented chronograph innovations—many introduced on the 5170 in 2010—now combined with a split-seconds mechanism that was designed from the ground up rather than grafted onto an existing architecture. Key technical achievements include an optimized rattrapante clamp for reduced drag, improved tooth profiles for smoother engagement, a redesigned column-wheel cap for shock resistance, and a significantly more stable amplitude during split-seconds operation—long a weakness of classic rattrapante architecture.

As with almost all modern high-complication Pateks, the manufacture has never released official production totals. However, based on case-number ranges, retailer data, and auction visibility, collectors generally estimate roughly 50–70 examples of the 5370P-001 (black enamel) produced from 2015–2020 and approximately 30–50 examples of the 5370P-011 (blue enamel) produced from 2020 onward, with total lifetime production likely settling around 80–120 pieces combined (not including the recently announced 5370R). Regardless of the precise number, the 5370 stands as one of the most important modern Patek Philippe complications: a demonstration of technical sovereignty, traditional Genevan finishing at its apex, and a quiet but proud return to the golden age of the pure split seconds.

This 5370P presents in excellent overall condition. Its case bears only very light signs of wear. Hallmarks are deep with sharp lug definition. Its dial shows no faults or signs of damage. The clasp, even, appears hardly worn. Its calibre Calibre CHR 29-535 PS is running well in specification on our timing equipment with all chronograph functions operating properly. Sale includes watch, original strap, deployant clasp, box, papers, and all original accessories.

This example is modelled on an average-sized 7-inch wrist.