A fake Audemars Piguet Royal Oak Offshore 25721ST is a watch that copies the 42 mm steel Offshore case and Mega Tapisserie dial but was not built by Audemars Piguet. The reference dates to 1993, when AP launched the Offshore as a heavier, sportier version of the Royal Oak. Because the genuine watch trades for large sums, copies of the 25721ST are common. The tells sit in four places: the dial grid, the bezel screws, the crown and pusher hardware, and the movement visible through the back.

Reference Facts to Compare Against

Learn the baseline before you look at any listing.

  • Case: 42 mm stainless steel, roughly 14.5 mm thick, with rubber coated crown and pushers on early production.
  • Dial: black Mega Tapisserie grid pattern with applied white gold markers and hands.
  • Bezel: eight hexagonal screws with slots cut to line up around the ring.
  • Movement: AP calibre 2126 on the first series, later 2326, both built on Jaeger-LeCoultre bases.
  • Caseback: reference and serial numbers engraved with even depth and consistent font.

Steps to Check a Suspected Fake

  1. Measure the case across the bezel from 3 to 9 o'clock, not including the crown. The number should read 42 mm.
  2. Measure the case thickness at the edge of the caseback. The figure should land near 14.5 mm.
  3. Turn the watch over and study the caseback engraving. Look at font weight, letter spacing, and cut depth.
  4. Examine each bezel screw under a loupe. The slot on every screw should sit flush and align with the case ring.
  5. Inspect the dial grid with a loupe. The raised squares should have sharp edges and repeat at an even pitch.
  6. Work the crown and both pushers. Travel should be smooth with no grit and no wobble in the guards.
  7. Check the date window and its magnifier. The aperture should sit square to the dial print and show the same magnification across the glass.
  8. View the movement through the display back if the watch has one. Rotor text, bridges, and perlage should read crisp under magnification.
  9. Weigh the watch against a documented figure for a steel 25721ST on its full bracelet. Copies frequently miss the mark because of hollow links and a thinner case.

Where Copies Usually Fail

  • Tapisserie squares that look stamped rather than cut, with soft corners.
  • Bezel screws that sit proud of the bezel or have slots pointing in random directions.
  • Crown and pushers made of plain steel instead of the rubber coated finish used on early examples.
  • Bracelet links with sharp inner edges and gaps that vary from link to link.
  • Movement finishing that shows brushed surfaces where the genuine calibre is decorated.
  • Dial print that bleeds at the edges of the AP logo and the depth rating text.

Verification Before You Buy

  1. Ask the seller for close, straight-on photos of the dial, caseback, and movement.
  2. Request the serial number and compare the engraving style against known genuine examples.
  3. Ask for any service records or an extract from the archives.
  4. Have an independent watchmaker open the case and confirm the calibre number and finishing.
  5. Walk away if the price sits far below the current market for a steel 25721ST, since that gap is the strongest single signal of a copy.

The 25721ST is a well documented reference, so authentication rarely depends on one detail. It depends on a set of details that all have to agree. When the dial, the screws, the hardware, and the movement line up with the reference facts, the watch is worth a closer look.