The pick here is the genuine watch, and the criteria that decide the question are the movement architecture, the dial printing and hand geometry, the case dimensions and weight, and the paperwork. Reference numbers in the IW3717xx block sit inside IWC's Portugieser Chronograph family, and IWC's reference blocks shift over time, so confirm the exact specification against the brand's own published collection data before you accept any seller's description. A counterfeit usually reveals itself in the first three checks and always reveals itself in the fourth.
Genuine IW371761: what the money actually buys
A genuine Portugieser Chronograph is a documented object. The reference, the serial, the service history and the case metal can all be traced, and the chronograph movement inside is a heavily reworked unit rather than a stock one. That matters because the parts exist, a qualified watchmaker can service it, and the case finishing holds up under a loupe.
- A movement that can be regulated, serviced and repaired with factory parts.
- Engraving, dial printing and hand finishing that survive close inspection.
- Paperwork that matches the case, which is what the secondary market pays for.
- Water resistance that means what the specification says.
- Price. This is the whole reason counterfeits exist.
- Boutique availability can be tight on limited references.
- Servicing costs real money every several years.
Use case: buy genuine if you intend to wear the watch for years, resell it, or hand it down. The paperwork is a large part of the value and it is the part a counterfeit can never supply.
Counterfeit IW371761: what the low price actually buys
The honest list is short. A counterfeit costs less up front, and that is the only item in the pro column. Everything else is a liability.
- Lower upfront cost.
- The movement is typically a stock chronograph or a low-grade module, not the reworked calibre the real watch uses. Subdial behaviour and hand reset give this away.
- Case thickness runs heavy, because the case has to hide a movement that does not fit the original proportions.
- Caseback engraving is shallow, and the font weight and letter spacing are usually wrong.
- Water resistance is unverifiable. Swimming with it is a gamble on a gasket nobody inspected.
- IWC will not service it, and many independent watchmakers will not open it.
- Resale value is effectively zero.
Use case: there is no scenario where a counterfeit IW371761 is the sensible purchase. If you want the look at a low price, buy a legitimately branded chronograph that copies no trademarks and states its own movement honestly.
How to inspect a suspected fake IW371761
- Verify the reference first. Ask the seller for the reference, serial and the original card. If the reference on the card does not match the caseback, stop there.
- Look at the subdials. Portugieser chronographs place their subdials at 12 and 6. Check the spacing, the depth and whether the hands sit flush. Fakes often show uneven spacing or a subdial hand that overhangs its track.
- Read the dial print under magnification. Check the wordmark letterforms, the thickness of the minute track, and whether the applied numerals sit level. Print that smears at the edges is a strong signal.
- Feel the pushers and crown. Genuine chronograph pushers have a defined, clean travel. Mushy or grinding pushers point to a cheap movement behind the dial.
- Weigh it and measure it. Compare the thickness and lug-to-lug figure against published specifications. Replicas run thick more often than they run thin.
- Inspect the caseback engraving. Depth, font and alignment should be crisp and consistent. Laser-etched lettering with no depth is a common replica tell.
- Check the crystal. Genuine sapphire with anti-reflective treatment almost disappears at an angle. Coated mineral glass shows a purple or green cast.
Legal exposure in the United States
Counterfeit watches are not a grey area in U.S. law. Importing merchandise that carries an infringing trademark is prohibited, and U.S. Customs and Border Protection can seize and destroy shipments. Civil liability runs to the seller, and buyers who resell a counterfeit can face claims under the Lanham Act as well. Beyond the legal side, buyers of counterfeits routinely lose money to sellers who take payment and disappear, since there is no recourse through the brand and no warranty to enforce.
Which choice fits your situation
If you want a genuine Portugieser Chronograph and the budget is not there yet, buy a pre-owned example from a dealer who provides the original card, or wait. If you want the aesthetic only, a well-made chronograph from an established mid-market brand gives you a comparable dial layout and a movement that can be serviced. If someone offers you an IW371761 far below market with no card, the correct move is to walk away, because the price gap is the cost of the paperwork you are not getting.