1. A concentration with a Community dimension as defined in Article 1, or which is to be examined by the Commission pursuant to Article 4(5), shall not be implemented either before its notification or until it has been declared compatible with the common market pursuant to a decision under Articles 6(1)(b), 8(1) or 8(2), or on the basis of a presumption according to Article 10(6).

2. Paragraph 1 shall not prevent the implementation of a public bid or of a series of transactions in securities including those convertible into other securities admitted to trading on a market such as a stock exchange, by which control within the meaning of Article 3 is acquired from various sellers, provided that:

(a) the concentration is notified to the Commission pursuant to Article 4 without delay; and

(b) the acquirer does not exercise the voting rights attached to the securities in question or does so only to maintain the full value of its investments based on a derogation granted by the Commission under paragraph 3.