A fake IW328073 usually fails in four places: the caseback engraving, the dial print under magnification, the movement finish, and the price. Genuine IWC engraving is crisp and even in depth, dial text sits sharp with no ink bleed, and the movement matches the calibre IWC lists for that reference. If any one of those four checks fails, stop and walk away.

What you need before you start

  • A 10x jeweller's loupe
  • A bright desk lamp and a phone torch
  • Full-resolution photos from the seller, not compressed listing images
  • The box, warranty card and any service paperwork, if they exist

Confirm the reference exists

  1. Look up the full reference in IWC's own model archive or an authorised dealer's catalogue. A reference that returns nothing anywhere is a warning sign in itself.
  2. Compare case size, dial colour and strap options listed by IWC against the watch in front of you.
  3. Match the serial number on the caseback to the number on the warranty document and the box label. All three should agree.
  4. Ask for the original invoice. A watch that cannot be traced to a documented sale carries more risk than one that can.

Inspect the case and caseback

  1. Hold the loupe over the caseback engraving. Genuine engraving has uniform depth, sharp edges, and no blurring at the corners of letters.
  2. Run a fingernail across the engraving. Copies often feel raised or rough because the marking sits on a plated surface.
  3. Check the lug brushing. It should run in one direction and stop at a clean line where the polished flank starts.
  4. Look at the crown. It should seat flush against the case, turn with light resistance, and show sharp relief on the IWC probus mark.

Read the dial and hands

  1. Magnify the dial text. The brand name and city line should be sharp, level and evenly spaced.
  2. Check marker alignment. Applied indices should sit parallel to the rehaut with equal gaps around the dial.
  3. Inspect the date window. The disc should be flat and matte, and the numerals should match the font used on the reference you verified.
  4. Charge the lume with a phone torch for 30 seconds. Genuine lume glows even and fades over hours. Cheap copies glow patchy and fade in minutes.
  5. Look at the hands under raking light. Genuine hands are polished on the bevels and flat on top, with no tool marks.

Check the movement

  1. Ask for a clear photo of the movement through the caseback, or have a watchmaker open it in front of you.
  2. Compare rotor engraving, jewel count and surface finishing against the calibre IWC specifies for that reference.
  3. Put the watch on a timegrapher. A beat rate that does not match the stated frequency points to a substituted movement.

Test the price and the seller

  1. Compare the asking price with completed sales on established secondary-market platforms. A discount of more than 25 to 30 percent below that range needs a documented reason.
  2. Ask where and when the watch was bought, and request the receipt from that purchase.
  3. Pay with a method that offers a chargeback. Bank transfer and crypto remove your recourse.
  4. Meet at an authorised dealer or a watchmaker for handover when the value justifies the trip.

If you already bought one

  1. Stop wearing the watch and photograph every angle, including the caseback and any paperwork.
  2. Get a written opinion from an independent watchmaker who does not sell watches.
  3. Contact the seller in writing, state the problem, and keep every message.
  4. Report the sale to the platform and, in the US, to the FTC and your state attorney general.