First introduced in 1972, the Royal Oak was Audemars Piguet’s inaugural stainless steel time-only sports watch, boasting an incredibly modern and sporty aesthetic, fitted with an integrated bracelet. An unusual release during the peak of the Quartz Revolution, this robust design became the blueprint that set the boom of luxury sports models in motion.

Just twelve years after its conception, the ref. 25554 was unveiled in 1984 as the "OG” Royal Oak Perpetual Calendar wristwatch. Striving to fuse form with function, the firm incorporated the compact yet commanding caliber 2120/2800 into the thin Royal Oak case, making the ref. 25554 one of the world’s thinnest self-winding perpetual calendars at the time. The model was subsequently delivered in yellow gold, platinum and stainless steel, with an estimated 279 examples made throughout its 8-year production run, across all metals.

While the Royal Oak ref. 25554 laid the groundwork, it was the present model, ref. 25654, that cemented the success of the Royal Oak Perpetual Calendar. Between 1987 and 1999, a total of 851 examples left the Le Brassus workshops: 38 in platinum, 68 two-tone examples with stainless steel and white gold, 315 pieces in stainless steel and 430 pieces in yellow gold. While the two models are aesthetically quite similar, the ref. 25654 is cased in a slightly thicker case of 8.25mm rather than the preceding 7.50mm, which subsequently improved its water resistance capabilities.

The present Audemars Piguet Royal Oak Perpetual Calendar ref. 25654BA is a beautifully preserved example, boasting a highly collectible MK I dial. The layout of the dial includes all the fundamental indications of a perpetual calendar, but also features stick hands, which are rarely found in Royal Oak watches. The sub-dials are slightly sunken, adding depth and texture to the otherwise-flat champagne dial. Further defined by its small signature under the moon phase, along with its three gold pearled indexes at 3, 9 and 12 o’clock, the present lot possesses all the desirable traits collectors seek on the earlier examples of the reference 25654. In addition, the MK I dial does not include a leap year indication as this function was only added nine years later, following the upgrade of the movement to the caliber 2120/2802 in 1993.

Moving on to the case, the polished screws, bezel and case bevels provide a sharp contrast against the brushed surfaces of the case and bracelet. The watch retains its original unsigned crown, white gold clasp and clasp cover with the correct "AP" signature.

Having aged gracefully through the ravages of time, this well-preserved vintage gem is blessed with an attractive layer of patina on the case and will most certainly appeal to both novice collectors and discerning connoisseurs of the Royal Oak.