No single detail proves a ref 16402 is fake. Counterfeiters nail the octagonal bezel and then lose the fight somewhere else. I check three things first: the case flanks, the dial texture, and the movement. Do it with a loupe or a macro photo, not from across a counter.
The Fast Test
- Run your eye along the bezel screws. On a genuine watch they sit in a line around the octagon and the slots align. On most fakes they drift.
- Turn the watch edge-on. Genuine Royal Oak case flanks have a sharp bevel between brushed and polished surfaces. Fakes round it off.
- Ask for a movement photo through the caseback. No photo, no deal.
What the Reference Number Tells You
Reference numbers in the 16402 range get attached to Royal Oak listings, and sellers borrow adjacent numbers freely. Plenty of listings use a reference that does not match the dial layout, the case size, or the movement in the pictures. Before you argue about authenticity, confirm the reference exists and matches what you are looking at. Audemars Piguet publishes reference data, and a boutique can check a serial against their records.
Case and Bezel Finishing
This is where fakes give themselves up. Genuine Royal Oak cases are machined, then hand finished in stages: brushed top surfaces, polished bevels, crisp transitions. Under magnification the bevel lines are straight and even. On a fake they wobble, the polished edges are too soft, and the brushing runs the wrong direction on at least one surface. Look at the bezel screws too. Genuine screws are functional and sit flush; fakes often sit proud or have slots cut too wide.
Dial and Tapisserie
The grid pattern on the dial is one of the harder things to copy. Genuine tapisserie is cut, not stamped, and the peaks catch light in a regular rhythm as you tilt the watch. Fake dials tend to look flat or muddy, with squares that are the wrong depth or spacing. Check the printing as well. Applied logos and printed text should be sharp at 10x magnification. If the lettering looks fuzzy or the indices sit crooked, stop there.
Bracelet and Clasp
Look at the link edges and the gaps between links. Genuine bracelets are tight but not stiff, and the end links meet the case with no step. Fakes show uneven gaps, a rattly feel on the wrist, and a clasp that closes with a hollow click. Engraving inside the clasp is another giveaway. It is shallow and uneven on most counterfeits, and the font is close but not identical.
Movement and Caseback
If the watch has a display back, the movement is the hardest part to fake well. Genuine finishing includes Geneva stripes, chamfered bridges, and polished screw heads. Copies use plated bridges, rough edges, and generic rotors with the wrong font. Engraving on the caseback should be crisp and centered. Reference and serial numbers should be consistent with the paperwork and with each other. If a seller refuses a clear movement photo, treat that as an answer.
Weight, Sound, and Feel
Fakes are often lighter and their rotor makes a cheap scraping sound when you shake them. That is not proof on its own, since some copies use heavy steel or real gold. Use it to decide what else to check, not to reach a verdict.
Paperwork and History
Ask for the original invoice, service records, and box. Call the boutique and ask them to confirm the serial. Audemars Piguet will not service or authenticate a counterfeit, and that refusal is useful information. A seller who has a friend at the boutique but no documents is a seller to walk away from.
What If You Already Bought One
Selling a counterfeit watch is trademark infringement, and it can bring civil liability and, in the US, criminal exposure. Owning one is a different question, but you cannot resell it as genuine and you should not try. If you bought a fake online and paid with a card, dispute the charge. Keep the listing, the messages, and the photos.