Quick answer: IW9380601 is written in IWC's reference format, and a fake IW9380601 is any watch sold under that number that never came out of Schaffhausen. The number on its own proves nothing in either direction. What matters is whether the reference exists in IWC's records, and whether the watch in front of you matches the configuration that reference is supposed to have.
What the IW format tells you, and what it does not
IWC stamps references as IW plus digits, and the leading block groups the watch into a family. That part is useful: it sorts a watch into a model line, a movement generation, and a rough production era. The trailing digits point to case metal, dial variant, and whether a bracelet or strap was fitted. Two watches can share a case and differ only in the last digit.
What the format cannot do is authenticate anything. A reference is a label. Anyone with an engraving tool can put one on a caseback, and the more obscure the number, the less likely a buyer is to have seen a real one for comparison.
Why listings for uncommon numbers look strange
When a code is rare or discontinued, search results thin out. One listing can dominate the page, sometimes copied and reposted across several sites with the same photos and a rotating set of prices. That is exactly the environment a counterfeit hides in, because there is no crowd of real examples to argue with it.
Checkpoints I go through, in order
- Caseback engraving. Real engraving has uniform depth and sharp terminals. Fakes show shallow, rounded letters and uneven spacing between the reference and the serial.
- Dial printing. Look at the logo and the minute track with a loupe. Weak kerning and slightly thick indices are common tells.
- Movement. Open the back or ask for movement photos. Check the beat rate, the rotor engraving, and the finishing on the bridges.
- Crown, pushers, and date change. A date that flips lazily or a crown with gritty threads does not match the price being asked.
- Papers, box, and card. A warranty card whose serial does not match the case is a bigger problem than a missing box.
- Price. If the number is far below every comparable listing, assume someone is hoping you will not ask why.
Verifying a reference without guessing
IWC's service department can confirm whether a reference was produced and how it left the factory. A watchmaker with an IWC parts account can open the case and read the movement number. Ask the seller for a photo of the caseback and the movement, then compare fonts and layout against owner photos of the same reference. If a seller refuses either photo, that is your answer.
If you are shopping replicas
Replica sellers use real IW codes because that is what buyers search for. IW9380601 on a replica listing is a style label, not a claim of provenance, and no honest listing should suggest otherwise. Buy a replica knowing it is a replica, and treat any seller who calls one genuine as someone to avoid.
Bottom line
The reference is a starting point for research, not a certificate. Confirm the number exists, confirm the configuration matches, and confirm the movement and serial line up. Do those three things and the question of fake or not answers itself.