Duplicate goods on subdomains of sellers, how to overcome?

Question

Electronic commerce

A service is planned where sellers can create their own website (subdomain) and post products. But I would not want these products to be duplicated with products on our main domain.
What solution methods exist?
So far, only by the name of the product, if you display a notice ...

Answer 1

What do you mean? The product must have information to which seller/domain it belongs, so filter by this info.