the exemption provided for in Articles 3 and 10 shall also apply to consortia whose share of the trade exceeds the limit laid down in Article 6 but does not, however, exceed 50 % of the direct trade, on condition that the agreements in question are notified to the Commission in accordance with the provisions of Commission Regulation (EEC) No 4260/88 (1), and that the Commission does not oppose such exemption within a period of six months. The period of six months shall run from the date on which notification is received by the Commission. Where, however, the notification is made by registered post, the period shall run from the date shown on the postmark of the place of posting.