Short answer
Most fake Blancpain 5050-1130-52A watches give themselves away before you ever open the case. Check the bezel insert, the caseback engraving, the dial print under a loupe, and the feel of the crown. If the seller will not send clear, straight-on photos of those four things, walk away.
Start with the reference itself
Blancpain reference numbers are structured, not random. The digits split into case family, case material or finish, and the strap or bracelet code at the end. That means a 5050-1130-52A has to match on every block, and sellers who list a watch as this reference while showing paperwork for another one are usually working from a stock photo set. Ask for a photo of the caseback with the full number legible, then compare it to what is printed on the certificate. A mismatch there is enough to end the deal.
What fakes of this reference get wrong
- Bezel insert. Modern Blancpain dive bezels use a sapphire insert with the markings applied beneath the glass. It reads with a slight depth and catches light along the edge. Replicas print on top of the sapphire, or use a coated ring, so the numbers look flat and the surface scratches like plastic.
- Caseback engraving. Laser etching looks shallow and slightly frosted. Genuine engraving is cut, with defined walls and consistent stroke width across the reference, serial, and Swiss Made line.
- Dial print. Under a loupe, real printing has clean borders. Copies show ink spread, uneven gap between the logo and the twelve, and markers that sit a hair off center.
- Movement. If there is a display back, you have the answer in front of you. In-house Blancpain movements show beveled bridges, circular graining, and a solid gold rotor with deep engraving. Clones hide a base movement under a decorative plate, and the lettering on that plate is usually burned rather than cut.
- Case proportions. Lug width, crown guard shape, and caseback thickness are the hardest things to copy cheaply. Run your thumb along the lug edges. A real case is polished through the transition; a fake has a crisp, unfinished ridge.
The seller side of the check
Paperwork is not proof on its own, but the absence of it changes the price. Ask for the original certificate, the service history, and whether the watch has ever been opened by a non-authorized watchmaker. A seller who refuses a video call with the watch running, or who insists on a bank transfer with no escrow, is telling you what you need to know.
Price reality
Secondary market pricing for a genuine example of this reference sits in a range that no honest seller will undercut by half. When a listing is priced at a fraction of the going rate, the explanation is almost never a motivated seller. Budget for an authentication service or a service estimate from an authorized Blancpain center. That cost is small compared to the loss on a counterfeit, and it is the only check that covers the movement properly.
If you already own a suspect watch
Stop wearing it in water and stop winding it hard. Have a watchmaker with Blancpain experience open the back and photograph the movement, the caseback inner stamping, and the dial feet. Dial feet are one of the quiet tells: genuine dials are located with feet in positions that match the movement, and swaps rarely line up. Get the report in writing before you contact the seller, and keep the listing screenshots.