Audemars Piguet Royal Oak Selfwinding Ref. 15400ST

Why the Royal Oak grew

Gérald Genta's Royal Oak of 1972 was nicknamed the 'Jumbo' because 39mm was considered oversized at the time. The everyday Royal Oak later settled at 36mm, and for decades that was the size most buyers knew.

Then the industry's taste changed, and Audemars Piguet's own archive gives part of the credit to its Royal Oak Offshore of 1993, a 42mm chronograph that dealers first called a sacrilege. In the brand's account, the Offshore led the watch industry into oversized watches, and the core Royal Oak followed: the 36mm Model 14790 gave way to the 39mm Model 15300 in 2003, and the 15300 was surpassed in 2012 by the 41mm Model 15400. One independent review dates the 15300 to 2005 instead, so the exact year of that earlier step is disputed.

The 15300 had been, in one writer's words, the Royal Oak 'the average consumer' bought: the same 39mm diameter as the ultra-thin Jumbo, a little thicker, with a seconds hand and Audemars Piguet's in-house Calibre 3120. At SIHH 2012 the brand replaced it with two references at once: the 41mm 15400 as the standard Royal Oak and a new 37mm 15450. The 39mm size was now reserved for the Jumbo and the skeleton models.

January 2012: a 40th birthday in Geneva

The 15400 arrived in the same week as the revised Jumbo 15202, both part of the brand's reworking of the Royal Oak collection for its 40th anniversary. A January 24, 2012 report laid out the choice for buyers: the Jumbo was the purist's watch, ultra-thin and without a seconds hand, while the new 41mm and 37mm models were the Royal Oaks 'that, in most cases, one will be buying,' built for daily wear.

Prices made the difference plain. The steel 15400 cost $16,900 in 2012, against $22,500 for the steel Jumbo. In pink gold the 15400 was $33,800 on a leather strap and $64,800 on a gold bracelet, and the 37mm 15450 started at $16,300 in steel. A review the following year gave the steel 15400's price as $16,700.

The changes from the 15300 were meant to be small. 'The Royal Oak is sacred to AP,' the same report said, 'so when revamping it, they had to be careful.' The most visible change was at 12 o'clock: the 15300 had its 'AP' logo there, while the 15400 moved the logo just below and restored the double baton hour marker that the first Royal Oak of 1972 had worn. The 'Grande Tapisserie' dials were now made in-house, rather than by an outside dial maker.

How to recognize one

The steel 15400ST measures 41mm across and 9.8mm thick, against 9.4mm for the 39mm 15300 by one account. The octagonal bezel is held by eight screws, the sapphire display back by eight more, and the crown screws down. The bracelet is the integrated steel Royal Oak bracelet with a folding clasp. Water resistance is 50 meters.

The dial is covered edge to edge in the 'Grande Tapisserie' pattern, with applied white gold hour markers, luminous Royal Oak hands, a center seconds hand, the applied 'AP' below 12 o'clock and the word 'Automatic' above 6. The giveaway is at 3 o'clock. The 15400 kept the 15300's movement, Calibre 3120, which is only 26.6mm across. In a 41mm case that pushed the date window well in toward the center, and Audemars Piguet filled the gap with a short extra hour marker beside it. Some collectors complained that the movement also looked too small through the caseback.

Calibre 3120 is self-winding, with 280 parts, 40 jewels, a 60-hour power reserve and a beat of 21,600 vibrations per hour, and it measures 4.26mm thick. It winds in both directions through an engraved 22-karat gold rotor running on ceramic ball bearings, and its balance uses variable inertia blocks. The bridges carry Geneva stripes, and the seconds hand stops when the crown is pulled to set the time.

The last two digits of the full reference give the dial: .01 black, .02 silver, .03 blue and .04 gray. The blue .03 is sold today as a 'Boutique Edition,' and one auction catalog notes that among 15400s the blue dial is especially sought after. A two-tone steel and pink gold 15400SR with a cream-colored dial followed at SIHH 2015, priced at $25,600.

Retirement and the market since

At SIHH in January 2019 Audemars Piguet retired the 15400 and introduced the ref. 15500, with the new Calibre 4302. At 32mm across, the new movement let the date window move back out to the edge of the dial, and the short marker beside it disappeared. The new movement beat faster, at 28,800 vibrations per hour, ran 70 hours instead of 60, and made the case thicker, 10.4mm against 9.8mm. The 15500 also dropped the word 'Automatic' and moved the minute track to a plain ring outside the tapestry pattern. At discontinuation the steel 15400 cost CHF 17,900; the 15500 started at CHF 19,300, or $19,200 in the US.

Not everyone welcomed the change. Readers of one launch report argued that the 15400 had the better dial proportions and narrower markers, and one predicted that the old model would become more desirable once it was gone. One reviewer called the 15500 'objectively better' but expected it to have its detractors and supporters, 'just like the 15400 did before.'

Auction results trace the rise. In December 2016 a circa-2012 black-dial example, sold new in the United States, made $13,750 in an online sale, above its $8,000 to $12,000 estimate. A blue-dial example from about 2015 sold for HKD 302,400 in Hong Kong in November 2022. In 2024 a circa-2013 silver-dial watch with its papers made $30,240 in an online sale based in Dubai, and a circa-2012 black-dial example with its original sales tag sold for $32,760. In May 2026 a black-dial 15400ST sold for HKD 279,400 in Hong Kong. In early October 2026, listings asked about $32,750 for a 2014 watch and $47,500 or more for blue-dial examples.

The Royal Oak most people bought

The 15400 was the standard Royal Oak for seven years, the reference that put the 41mm size at the center of the collection. The 15500 and its successor the 15510 kept the 41mm size it established.

Its two peculiarities, a date set in from the edge with a short marker beside it and a movement that looked small for its case, were the very things its successor fixed. They are also the quickest way to tell a 15400 from any later 41mm Royal Oak.

The numbers

Reference

15400ST.OO.1220ST (.01 black, .02 silver, .03 blue, .04 gray)

Caliber

Audemars Piguet 3120, self-winding, hours, minutes, center seconds and date; 280 parts, 40 jewels, 21,600 vph, 60-hour power reserve

Movement size

26.6mm by 4.26mm

Case

41mm stainless steel, 9.8mm thick, sapphire crystal and caseback, screw-locked crown, 50m

Dial

'Grande Tapisserie' pattern, applied white gold markers, double baton at 12, extra short marker beside the date

Production

2012 to 2019

Successor

Ref. 15500ST (2019), 41mm, Calibre 4302

Timeline

1. 1972

   Gérald Genta's 39mm Royal Oak is launched and nicknamed the 'Jumbo.'

2. 1993

   The 42mm Royal Oak Offshore is unveiled at the Basel fair.

3. 2003

   In the brand's account, the 36mm Model 14790 gives way to the 39mm 15300 with Calibre 3120.

4. Jan 2012

   At SIHH the 41mm 15400 and 37mm 15450 replace the 15300; the steel 15400 costs $16,900.

5. Mar 2013

   A review gives the steel 15400ST's price as $16,700.

6. Jan 2015

   A two-tone steel and pink gold 15400SR is shown at SIHH, priced at $25,600.

7. Dec 7, 2016

   A circa-2012 black-dial 15400ST sells for $13,750 in an online sale.

8. Jan 2019

   The ref. 15500 with Calibre 4302 replaces the 15400, last priced at CHF 17,900.

9. Nov 27, 2022

   A blue-dial 15400ST from about 2015 sells for HKD 302,400 in Hong Kong.

10. Apr 30, 2024

    A circa-2013 silver-dial 15400ST sells for $30,240 in an online sale based in Dubai.

11. Jun 10, 2024

    A circa-2012 black-dial 15400ST with its sales tag sells for $32,760.

12. May 28, 2026

    A black-dial 15400ST sells for HKD 279,400 in Hong Kong.

The world in 2012

• Jul 2012

  Scientists at CERN announce the discovery of the Higgs boson.

• Jul 27, 2012

  The Summer Olympics open in London.

• Aug 6, 2012

  NASA's Curiosity rover lands on Mars.

• Nov 6, 2012

  Barack Obama is reelected president of the United States.

• Jan 3, 2019

  China's Chang'e 4 becomes the first spacecraft to land on the far side of the Moon.

• Apr 10, 2019

  The Event Horizon Telescope team releases the first image of a black hole.

• Apr 15, 2019

  Fire destroys the spire and roof of Notre-Dame de Paris.

Price record

A realized auction price is what a buyer actually paid on the date shown, including the buyer's premium where the sale reported it. It is the strongest kind of reference price, and it is a record of one sale of one object on one day, not a promise of what the next example will bring.

By reference price, Audemars Piguet Royal Oak Selfwinding Ref. 15400ST is number 52 of 100 in the watches entries of the FLOAT 100. 54 of those 100 rest on a realized sale; the rest carry an asking price or a guide value, and each page says which. Rank within the FLOAT 100 itself (44 here) is editorial: how much an object defines its field, not price alone.

Did you know

• The short extra hour marker beside the 15400's date exists only because its movement was too small to put the date near the edge.
• The Royal Oak's growth from 36mm to 41mm is traced by the brand itself to the Offshore, a watch its own dealers first called a sacrilege.
• With the 15400, Audemars Piguet began making its 'Tapisserie' dials in-house rather than buying them from an outside dial maker.
• The 15400 has 'Automatic' printed above 6 o'clock; its successor, the 15500, dropped the word.
• In 2016 a 15400ST sold at auction for $13,750, less than its 2012 retail price of $16,900.