networks that allow them to create a “closed system” ie AD can sell to end users or other ADs admitted to the network only. If the AD sells to a grey dealer that is not authorized by the brand (without an individual buyer acting as a conduit) this is a breach of contract, likely triggering a penalty clause. A seasoned collector knows full well that this is the case and as a result knowingly takes advantage of the contract breach. In certain jurisdictions, at least in the EU, this may make the grey dealer AND the ultimate buyer liable as a consequence. I would be curious to see what happens if a brand brings a case against a buyer on this basis.