A fake IW3716 gives itself away in three places: the subdial layout, the caseback, and the movement. The real IWC Portugieser Chronograph ref. IW3716 runs the in-house calibre 69355 with a column wheel and vertical clutch, shows that movement through a sapphire caseback, and has no date window at all. If the watch in front of you has a date at 3 or 4:30, a solid steel back, or a rotor with printed text instead of engraved IWC markings, the conversation is over.
What the real IW3716 looks like
The reference covers a family of dials, silver-plated, blue, green, black lacquer, but the chassis stays the same. Stainless steel or gold, 41 mm across, roughly 13.1 mm thick, 30 m water resistance. Two subdials sit at 12 and 6. Chronograph minutes live at 12, small running seconds at 6. No date. Numerals are applied on the modern refs, and the leaf hands look thin enough to bend in photos, which is part of the charm. IWC seals it with a sapphire crystal up front and, on the 3716, another one on the back.
That last detail matters. The older Portugieser Chronograph 3714 used a modified Valjoux 7750 (calibre 79350) and hid it behind a solid caseback. The 3716 moved to the in-house 69355 and opened the back so you can see it. Any watch sold as a 3716 with a closed back is a 3714, or a replica dressed up as one.
The tells, in order of how fast they work
1. The date window
There isn't one. Not at 3, not at 4:30, not hidden under a black disc that ghosts a number at the wrong angle. The moment you spot a date aperture, you are looking at a cheap 7750 build with a printed dial.
2. Subdial spacing and hand height
On the genuine watch the two subdials sit tight to the center and the hands ride close to the dial. On a low-grade fake the subdials drift outward, the chrono hand floats above the markers, and the running seconds hand can sit a hair off center. Tilt it under a light and the gap shows.
3. The caseback
Engraving quality is the giveaway. Real IWC casebacks carry crisp, deep lettering with sharp edges. Replicas etch shallow and soft, and the fine print turns to mush. Reference and serial numbers are stamped cleanly between the lugs at 12 and 6.
4. The movement
Through the sapphire back you want a 69355: column wheel visible, Geneva stripes, blued screws, an open-worked rotor with the IWC engraving. A gold-plated ETA clone with a printed badge and a wobbling rotor is a fake every time. Winding tells you plenty too. The 69355 winds smooth and the pushers snap. A soft pusher with a chrono hand that jumps or stutters at start is missing the vertical clutch, and that is not something a replica can fake.
5. Dial print and lume
The IWC logo and SCHAFFHAUSEN text sit under the crystal with a slight relief. Fakes print flat, or the spacing is off by a millimeter. Plenty of 3716 dials carry no lume at all, so if a listing brags about glowing markers, check the exact reference photo before you believe it.
6. Strap and hardware
Alligator grain on the genuine strap has irregular scale, not a repeating stamp. The buckle engraving is as sharp as the caseback. On replicas the leather feels stiff and the buckle logo looks laser-etched.
Where even the best replicas fall short
Top-tier 1:1 makers now get the case profile, dial color, and hand shape close enough that photos fool people. What they still miss: the AR coating tint on the crystal, since IWC's is nearly colorless and reps flash blue or purple at an angle. The depth of the caseback engraving. The crispness of the applied numerals. The chronograph feel. And weight distribution. A real 3716 sits balanced on the wrist. A fake tends to feel top-heavy because the movement and caseback are not the same mass.
Quick checklist before you buy anything labeled IW3716
- Ask for one in-focus photo of the caseback, straight on.
- Ask for a short video of the chronograph starting, running, and resetting to zero.
- Confirm there is no date window.
- Get the reference number from between the lugs and match it to the dial variant.
- Tilt the crystal and check the coating color.
- Compare the thickness and weight against the published specs for that reference.
One more thing worth knowing. Lots of listings advertise a 3716 when the watch is really a 3714 with a swapped dial and a made-up reference. The 3714 is a good watch in its own right, but it has the solid back and the older movement. If a seller cannot tell you which one they are holding, they do not know the product, and that answers your question for you.