Short answer
A fake IWC Ingenieur sold as IW3220 fails three checks. The reference number is incomplete, the case measures wrong, and the movement is not an IWC calibre. Run those checks before money changes hands and most counterfeits fall out.
What IW3220 means
IWC builds reference numbers from a prefix plus digits. IW3220 is a prefix. A full number reads IW3220xx, for example IW322701. The 2005 Ingenieur Automatic IW322701 has a 42.5 mm steel case and IWC calibre 80110 with Pellaton winding. A listing that shows only IW3220 is a signal. Ask for a close photo of the caseback engraving. Counterfeit sellers copy the prefix because it reads correct at a glance. The digits after the prefix are where numbers stop matching.
Case and crystal
- Measure with calipers. Case diameter and thickness change between references in this family.
- Count the bezel screws. The 2005 Ingenieur Automatic has five. Heads sit flush with the bezel surface. Copies show raised heads and uneven gaps.
- Inspect the crown. IWC crowns carry the logo in relief and turn with clear detents. Copies use generic crowns with no mark.
- Check the crystal. Sapphire with coating on both faces keeps the dial readable at an angle. Haze or grey tint points to mineral glass.
Movement
Genuine watches in this line use IWC calibres. Counterfeits use ETA 2892, Sellita SW300, or unmarked Chinese movements. On models with a display back, look at the rotor, the engraving depth, and the bridge finish. On solid-back models, have a watchmaker open the case and read the calibre number. The fee is small against the price gap between a fake and a real watch.
Weight, bracelet, and clasp
Weigh the watch. Steel cases with integrated bracelets land in a narrow range. Copies use thin steel or plated brass and read light on a kitchen scale. Run a finger along the bracelet edges. IWC links are chamfered and consistent. Copies show tool marks and loose end links.
Papers and serials
Ask for the serial on the caseback and the matching number on the card. IWC does not run a public serial lookup. Confirm with IWC service or an authorized dealer. A price far under the market for the reference is the oldest signal. So is a seller who ships from a warehouse and blocks returns.
Service and resale
IWC service centers do not repair counterfeit watches. They return the watch. Resale value for a counterfeit sits near zero. If the seller calls the watch a replica, treat the listing as a replica and price it on that basis.