Short answer
A fake Da Vinci copy is a watch built by a third-party factory and sold as an IWC Da Vinci. The real Da Vinci is IWC Schaffhausen's dress line, launched in 1969. Copies sell from about $50 for a quartz model to $400 for an automatic. The gap shows up in the movement, the case metal, and the calendar work.
No known copy reproduces the IWC perpetual calendar module. That module is the hardest part of the watch to build and the first thing to inspect.
What the real watch is
IWC introduced the Da Vinci in 1969 with a Beta 21 quartz movement. In 1985 the line gained a perpetual calendar designed by Kurt Klaus, built on a Valjoux 7750 base with a module on top. Later versions moved to a tonneau case, then back to a round case in 2017. Case metals include stainless steel, 18k rose gold, 18k white gold, and platinum. Dials are silver-plated, slate, or blue, with applied indices.
Points to check
- Movement: IWC lists the caliber for each reference in its catalog. A copy usually holds a stock ETA or Seagull movement with no IWC marking under the rotor.
- Perpetual calendar: the real module tracks day, date, month, moon phase, and leap year, and needs no correction until 2100. Copies show printed windows that drift out of step within weeks. Some have no leap year indicator at all.
- Moon phase: the real disc advances on a geared train. Copies use a printed disc turned by the hour hand.
- Case metal: an 18k gold Da Vinci case has real weight. Gold-plated brass and steel copies feel light and lose plating on the lugs and crown.
- Caseback: IWC engraves the reference number, case number, "Probus Scafusia," and "Swiss Made." Copy engraving is shallow and the fonts are wrong.
- Crown: signed with the IWC mark, correct size, no wobble in the stem.
- Dial print: index alignment at 12, even lume plots, sharp text. Copies show uneven spacing and soft edges.
Numbers that do not add up
A working 18k perpetual calendar chronograph costs more than the gold in it. A $300 listing for the same watch is not gold and does not have the module. Reference numbers on the caseback should match the model in the IWC catalog. If the seller will not send photos of the movement, treat the watch as a copy.
Legal note
US law, 18 U.S.C. 2320, makes trafficking in counterfeit goods a federal crime. US Customs and Border Protection seizes counterfeit watches at entry and destroys them. Buying a copy carries risk of seizure and no warranty or service from IWC.