Editorial
The 15500 is the current-production steel Royal Oak in 41mm, powered by Audemars Piguet's fully in-house 4302 caliber. It replaced the 15400 in 2019 and is the reference most buyers mean when they say they want a Royal Oak. Blue, grey, and black sunburst dials give collectors a range of options, though blue remains the most sought after.
AP introduced the 15500 at SIHH 2019 as the direct successor to the 15400, which itself carried the Royal Oak line from 2012. The key upgrade was the 4302 movement: fully in-house developed and manufactured, with a 70-hour power reserve and improved finishing compared to the 3120 that powered the 15400. The 3120 sourced some components externally; the 4302 does not.
Three dial options launched at release: blue (ref. 15500ST.OO.1220ST.01), grey (ref. 15500ST.OO.1220ST.02), and black (ref. 15500ST.OO.1220ST.03). Production continues today, making it a current catalog reference.
Verify the movement serial matches AP records, particularly on grey-market pieces that may have traveled through multiple hands. The 4302 movement has a distinctive quick-set date pusher at 10 o'clock; if it is missing or shows wear inconsistent with the case, ask questions. Dial condition is critical: the sunburst finish shows scratches and cleaning attempts badly, and a re-polished or repainted dial will kill resale value.
Check the bracelet for excessive stretch and replaced links, since original AP bracelets wear predictably and a sudden dead link mid-bracelet suggests amateur repair. Confirm the inner bezel screws are intact and undamaged, as stripped screws are a common sign of amateur opening.
