(2)Regulation (EC) No 139/2004 is based on the principle of compulsory notification of concentrations before they are put into effect. Notification has important legal consequences which are favourable to the parties to the proposed concentration. However, failure to comply with the obligation to notify renders the parties liable to fines and may also entail civil law disadvantages for them. It is therefore necessary in the interests of legal certainty to define precisely the subject matter and content of the information to be provided in the notification.