If your design is not registered, you will not have exclusive rights and will be unable to prevent third parties from using it without your consent. If you suffer a financial loss as a result, you will not be able to sue for compensation on the basis of the legal rules on industrial designs. You may, in certain circumstances, be able to have third parties prosecuted for offences such as unfair competition or “reputation parasitism”, provided you can show that their actions directly caused your loss.
In the Principality of Monaco, however, if your industrial design is an original creation protected by artistic or literary copyright, you can take action against third parties who reproduce or represent it without your consent.