1. Member States shall require any natural or legal person or such persons acting in concert (the proposed acquirer) who have taken a decision either to acquire, directly or indirectly, a qualifying holding in an insurance or reinsurance undertaking or to further increase, directly or indirectly, such a qualifying holding in an insurance or reinsurance undertaking as a result of which the proportion of the voting rights or of the capital held would reach or exceed 20 %, 30 % or 50 % or so that the insurance or reinsurance undertaking would become its subsidiary (the proposed acquisition), first to notify in writing the supervisory authorities of the insurance or reinsurance undertaking in which they are seeking to acquire or increase a qualifying holding, indicating the size of the intended holding and relevant information, as referred to in Article 59(4). Member States need not apply the 30 % threshold where, in accordance with Article 9(3)(a) of Directive 2004/109/EC, they apply a threshold of one third.