Audemars Piguet does not publish a calibre numbered 3399. The brand's perpetual calendar references, such as the Royal Oak 26574, run on calibre 5134. A listing that carries 3399 appears to be a seller code or a mislabel. Treat the number as a catalog tag, not a movement name.
What a real perpetual calendar does
A perpetual calendar tracks month length and leap years. It needs no manual correction until 2100, because 2100 is not a leap year under the Gregorian rule. Calibre 5134 carries a 40-hour power reserve and drives day, date, month, moonphase, and leap year displays. The Royal Oak 26574 case measures 41 mm.
What replica versions do
- Replicas from $80 to $200 use quartz or a basic automatic movement with printed calendar subdials. The date wheel moves once every 24 hours. It has no month logic.
- Replicas from $250 to $600 add a calendar module. These act as annual calendars at best. The owner sets the date after February and after each 30-day month.
- Replicas from $700 to $1,200 copy case finishing, sapphire crystal, and tapisserie dial texture. The moonphase disc is often a printed image, not an engraved disc.
Checks at the point of sale
- Set the watch to February 28 and advance the date. A true perpetual calendar jumps to March 1. A replica lands on February 29 or stalls.
- Find the leap year indicator. If the dial has one, confirm it moves at the correct point in the four-year cycle.
- Inspect the bezel screws. AP sets the eight hexagonal screws in one direction. Replicas show slots at random angles.
- Compare the date font and the window cut against catalog photos. AP uses a set typeface and a specific aperture shape.
- Ask for the movement number. Calibre 5134 is stamped and engraved. A blank or printed rotor is a sign of a generic automatic.
Legal status in the US
Counterfeit watches infringe trademarks under 15 U.S.C. 1114. Import is barred under 19 U.S.C. 1526. US Customs and Border Protection seizes counterfeit goods and can assess civil penalties on the importer. Trafficking in counterfeits carries criminal penalties under 18 U.S.C. 2320. Resale of a fake as genuine also exposes the seller to civil damages.
Cost and repair notes
Replica calendar modules are hard to service. Parts for a cloned module come from the same seller, and many repair shops refuse the work. A genuine calibre 5134 service runs in the hundreds of dollars plus parts. For a replica, the service quote can exceed the purchase price.