A fake IW371499 is a counterfeit of the IWC Portugieser Chronograph, and the quickest way to catch one is to turn it over. Genuine watches in the IW3714 family run a modified Valjoux 7750, IWC caliber 79350, and that movement has a very specific look: a big brass-colored balance, a column of levers under the rotor, and finishing that is brushed in one direction, not mirror-polished everywhere. Replicas almost always use a stock 7750 with a decorated rotor plate glued on, or worse, a cheap chronograph module where the pushers feel mushy and the reset snaps back with a click you can hear across a room.
What the reference actually is
The IW3714 line is the classic Portugieser Chronograph: roughly 40.9mm across, about 12.6mm thick, leaf hands, applied numerals, a 30-minute totalizer at 12 and running seconds at 6. No date window on most of these. The dial is the whole point of the watch, and it is also where fakes fall apart fastest.
Reference numbers in this family are numerous and details shift between production runs. If someone is selling you a specific IW371499, check the number against IWC's own reference records and against photos of that exact variant before you argue about anything else. A seller who cannot show you the caseback engraving clearly is already a problem.
Dial and hands: where I look first
- Printing. Genuine Portugieser dial text is thin, crisp, and slightly raised. Fakes look flat, and the "IWC" letters often sit a hair too close together or too bold.
- Subdial spacing. The two subdials should sit on a clean vertical axis, centered under the 12 and above the 6. Replicas drift a half millimeter off and it reads as sloppy from arm's length.
- Leaf hands. They should be faceted, with a sharp central ridge and clean edges. Fake hands are often stamped, with rounded edges and a dull ridge.
- Applied numerals. Look at the side profile. Real ones are polished on top and the sides catch light. Fake numerals look painted-on-flat or sit in a visible glue bed.
- Crystal. Genuine sapphire has double-sided antireflective coating, so the dial almost disappears at an angle. Cheap fakes show a blue or purple sheen and a visible halo.
Case, crown, and finishing
Run a fingernail along the lug edges. Genuine IWC case work is even, and the transition from brushed flank to polished bevel is a distinct line, not a smeared gradient. On fakes the brushing is often too coarse, the bevel too wide, and the lugs slightly thicker than they should be.
The crown is a good tell too. It should be signed crisply, sit flush, and wind with light resistance. Pushers should have a short, firm travel with a clean start and stop. If the chronograph feels spongy or the pushers wobble sideways, walk away.
Movement and caseback
Ask for a clear photo of the movement through the display back. You want to see the 79350 architecture: the balance in the right place, the correct bridge shapes, and engraving that is cut into the metal rather than printed on a plate. Rotor text on fakes is frequently too large, too shallow, or spells something slightly wrong.
Engraving on the caseback rim should be deep, sharp, and consistent in depth. Reference and serial numbers should be legible under a loupe, not blurry dots.
Paperwork and price reality
Genuine IW3714 references trade well into four figures on the secondary market. A "new in box" example at a third of that price is not a bargain, it is an answer. Boxes, booklets, and warranty cards are widely faked, so treat paperwork as supporting evidence, never as proof.
- Get the movement photo before anything else.
- Compare dial printing against a known-good photo of the same reference.
- Check the caseback engraving depth under magnification.
- Feel the pushers and the crown wind.
- Ask for service history or a recent timing report.
None of these checks takes more than ten minutes. Skipping them is how people end up with a very convincing watch that nobody will service.