Launched in 1982, the Royal Oak Perpetual Calendar combines two of the great icons of Audemars Piguet’s heritage, the Royal Oak model and the perpetual calendar complication. The skeletonized version was introduced in the 1990s to allow the incredible finish of the movement to be visible through both the sapphire crystal case back and the dial and bringing a stunning new aesthetic to the Royal Oak model. Created in a limited edition of 41 examples, the present lot is number 4 of 41 in a platinum case and skeletonized dial with blue outlined subdials. Produced from 1986 to 1996, the present lot is made rarer due to the exclusion of a leap year indicator. The present lot is in the last generation of Audemars Piguet skeletonized perpetual calendars to be sold without the leap year indicator.