In line with the commonly established concept of substantial modification for products regulated by Union harmonisation legislation, where a substantial modification occurs that may affect the compliance of a product with digital elements with this Regulation or when the intended purpose of that product changes, it is appropriate that the compliance of the product with digital elements is verified and that, where applicable, it undergoes a new conformity assessment. Where applicable, if the manufacturer undertakes a conformity assessment involving a third party, a change that might lead to a substantial modification should be notified to the third party.