{"reference": {"slug": "patek-philippe-5951p-001", "brand": "Patek Philippe", "ref": "5951P-001", "model": "Perpetual Calendar Split-Seconds Chronograph", "case_material": "Platinum", "provenance": "extracted_from_auction_comps", "url": "https://mostexpensivewatches.net/reference/patek-philippe-5951p-001", "description": "The Patek Philippe 5951P-001 was introduced in 2010 and remained in production until approximately 2015. This reference is distinguished by its cushion-shaped platinum case and the caliber CHR 27-525 PS Q, which remains the thinnest column-wheel split-seconds chronograph movement with a perpetual calendar ever produced by the manufacture. Collectors prioritize this model for its technical density, as the movement measures only 7.3mm in height despite its 400 components. The dial features a black lacquer finish with red accents and white gold Breguet numerals, a departure from the brand’s traditional aesthetic. On the secondary market, the 5951P-001 typically commands prices in the mid-to-high six-figure range, often between $350,000 and $500,000 depending on provenance. A notable production detail is the single Top Wesselton diamond set into the case at 6 o'clock, signifying its platinum construction. Low production numbers make this reference a rare find at auction."}, "listing_stats": {"count": 1, "median": 57500.0, "low": 57500.0, "high": 57500.0, "brands": 1, "merchants": 1}, "listings": [{"id": "h_7516691431511", "title": "Patek Philippe Patek Philippe Annual Calendar Moonphase", "brand": "Patek Philippe", "model": "Patek Philippe Annual Calendar Moonphase", "reference": "—", "price_usd": 57500.0, "currency": "USD", "condition": "excellent", "box_papers": "full_set", "year": null, "case_material": "Stainless Steel", "case_size_mm": 40.0, "movement": "Automatic", "complications": ["Perpetual Calendar", "Annual Calendar", "Moon Phase"], "merchant_slug": "analog-shift", "merchant_name": "Analog/Shift", "image_url": "https://cdn.shopify.com/s/files/1/0809/1255/files/AS11404_40930858_PATEKPHILIPPE_ANNUALCALENDARWGBLUEDIAL_5205G-013--6.jpg?v=1763910931", "detail_url": "https://mostexpensivewatches.net/listing/h_7516691431511", "buy_url": "https://mostexpensivewatches.net/out/h_7516691431511", "alt_buy_urls": [{"partner": "goldsmiths", "name": "Goldsmiths", "region": "UK", "url": "https://mostexpensivewatches.net/out/h_7516691431511/via/goldsmiths"}, {"partner": "selfridges", "name": "Selfridges", "region": "UK", "url": "https://mostexpensivewatches.net/out/h_7516691431511/via/selfridges"}, {"partner": "farfetch", "name": "Farfetch", "region": "Global", "url": "https://mostexpensivewatches.net/out/h_7516691431511/via/farfetch"}], "available": true}], "auction_lots": [{"slug": "patek-philippe-5951p-001-2023", "brand": "Patek Philippe", "reference": "5951P-001", "model": "Perpetual Calendar Split-Seconds Chronograph", "case_material": "Platinum", "hammer_usd": 355000, "year_sold": 2023, "venue": "Bonhams London", "lot_summary": "An exceptionally rare platinum cushion-form grand complication featuring the ultra-thin caliber CHR 27-525 PS Q, which was the thinnest column-wheel split-seconds chronograph movement at its launch.", "source_url": "https://www.bonhams.com/auctions/28011/lot/100/", "provenance": "ai_generated_grounded", "url": "https://mostexpensivewatches.net/auctions/patek-philippe-5951p-001-2023"}, {"case_material": "Platinum", "recap_slug": "london-fine-watches", "year_sold": 2026, "provenance": "auction_desk_verified", "source_url": "https://www.bonhams.com/auctions/28123/", "model": "Perpetual Calendar Chronograph", "lot_summary": "Verified result from London Fine Watches (Bonhams London), concluded 2026-06-11. Reported by the MostExpensiveWatches auction desk with primary sources on file.", "hammer_usd": 352000, "venue": "Bonhams London", "brand": "Patek Philippe", "reference": "5951P-001", "slug": "patek-philippe-perpetual-calendar-chronograph-5951p-001-2026-bonhams-london", "url": "https://mostexpensivewatches.net/auctions/patek-philippe-perpetual-calendar-chronograph-5951p-001-2026-bonhams-london"}]}