Of the thousands of watches released each year, there are very few that could genuinely be called “design classics”.

Audemars Piguet’s Royal Oak is one of them.

With its octagonal case and exposed screw-heads, it was highly unusual when it come out in in 1972. It looked weird. Weirder still was its positioning. It was a sports watch, sold as a luxury item… but made of steel.

It cost about £1,600, an extortionate amount back then. At the time an 18kt gold Rolex Submariner would have set you back £360.

“At a price like this, why don’t they conceal the bolts?” asked one of AP’s own provocative advertisements.

It was seen as a huge risk when it was created by the eminent watch designer Gérald Genta. History shows it turned out to be one of the smartest moves a watch company ever made – today the Royal Oak is said to account for well over half of AP’s annual sales, in the tens of millions.

audemars piguet
Audemars Piguet

Over five decades its desirability has seldom waned. As recently as last year it was being heralded as ‘Hollywood’s Favourite Watch’, seen on the wrists of a new era of zeitgeist-y celebs including Travis Scott, Drake and Steph Curry.

This year the Royal Oak turns 50. Marketing departments at watch companies scarcely need much encouragement to celebrate anniversaries of any kind – it’s always the 45th birthday of some model or other, or 30 years since the first X could do Y.

But this one is genuinely worth celebrating.

While Audemars Piguet is busy with a full year’s worth of new limited-edition Royal Oaks, all of which have so far sold-out within hours, the model’s back catalogue has also been doing brisk business.

Next month the auction house Phillips hosts a sale dedicated to Royal Oaks of special historical interest.

The Royal Oak 50th will be held in Geneva and feature 88 of “the finest, rarest and best-preserved Royal Oaks known to exist”. Phillips says “to the best of our knowledge, we have never seen or heard of so many historically important, rare and, in some cases, unique Royal Oaks gathered in one place or shown to the public”.

A quick glimpse at the catalogue makes it hard to disagree.

Included in the auction is a model of the earliest reference 5402, carrying the number A2, meaning it was one of four of the first Royal Oaks to be shown to the press and public at the Basel watch fair in 1972, where reactions ranged from bafflement to outright disgust. That watch has an estimate of CHF 200,000–400,000 (around £162,000-£324,000).

Also on sale is Karl Lagerfeld’s Royal Oak. The late Chanel designer was a fan – often sporting different versions of the watch himself, before handing them out to friends as gifts. This one, also a ref. 5402, is coated in black PVD (a very Lagerfeld touch). Phillips is careful with its wording here, calling it “an icon probably worn by an icon” – photos of Lagerfeld wearing a black PVD Royal Oak certainly exist, though no one’s 100 per cent it’s this one.

If you’re tempted, the estimate is CHF 100,000-200,000 (£81,000-£162,000).

There are also various rare tourbillon and grand complications Royal Oaks up for sale.

Phillips has been on something of a record-breaking roll in recent years, having made global headlines with Paul Newman’s Rolex “Paul Newman” Daytona in 2017, sold for CHF 17,709,894 (about £14m), then the most-expensive wristwatch sold at auction, and getting CHF 11,020,00 (around £9m) for a Patek Philippe ref. 1518 the previous year – then the highest sale for a Patek.

Audemars Piguet has yet to scale those heights. Yet it is enjoying an unprecedented purple patch. According to The New York Times this year it climbed above its rival Patek Philippe in pure revenue terms for the first time in living memory, posting $1.6 billion (£1.2bn) in sales, an increase of about half-a-billion on 2020 estimates.

On the watch auction league table AP’s biggest hitter is also one of its most recent – at Number 16 is the Marvel superhero-themed Royal Oak Concept Black Panther Flying Tourbillon, that sold for $5.2m (£3.9m) in 2021, the same year it was released.

A golden period for a watch celebrating its golden anniversary, then.

In 1972 that £1,600 would have been money well-spent.

The Royal Oak 50th takes place on 6 May. More details here