Undeniably the keystone of Audemars Piguet's serially produced watches, the Royal Oak is why the landscape of the luxury sports watch market is the way it is. After Gerald Genta was brought in to assist Audemars Piguet in 1972, he famously was only given 24 hours to design 'a steel sports watch that has never been done before. Something totally new and waterproof.' The outcome was one of the most significant watches created and the catalyst that transitioned steel into the luxury sphere. During the post-1972 years, other watch brands began to follow suit and shift attention to steel, culminating in where the industry is today, with steel typically being more desirable than precious metals.

But Audemars Piguet is far more than a time-only watchmaker, and it wasn't long before the demand for a more complicated Royal Oak increased, providing the opportunity to remind the world of its technical proficiency. Encouraged by strong market demand, in 1983, the Royal Oak Day Date 5572 debuted a twin register Royal Oak encased in their newly launched 36mm case diameter from the same year. Capable of offering not just the current time but also the date and month, the success of this Royal Oak underpinned its unconventional platform. Produced in steel, yellow gold, white gold, and two-tone, the 5572 was renamed the 25572 between '84-85 and remained in the lineup until the late 1990s. The production numbers for each metal were even during its lifespan, excluding the white gold realizations, which account for less than 1%. Thanks to the 5572, another significant Royal Oak was produced featuring a moonphase, the 5594, the brand's longest standard reference.