14.3 Complying with Community Law 455The EC Merger Regulation contains two main rules on the assessment of con-
centrations.
First, a concentration which would not significantly impede effective competi-
tion in the common market or in a substantial part of it must be declared compati-
ble with the common market.^48 This may be, for example, where the market share
of the undertakings concerned does not exceed 25% either in the common market
or in a substantial part of it.^49
Second, a concentration which would significantly impede effective competi-
tion in the common market or in a substantial part of it must be declared incom-
patible with the common market.^50 This is especially the case where the signifi-
cant impediment to effective competition is a result of the creation or
strengthening of a dominant position. On the other hand, the notion of “significant
impediment to effective competition” extends beyond the concept of dominance.
For example, many oligopolistic markets exhibit a healthy degree of competition.
In such markets, the notion of “significant impediment to effective competition”
can cover, say, the anti-competitive effects of a concentration resulting from the
non-coordinated behaviour of undertakings which would not have a dominant po-
sition.^51
In addition to those two main rules, the EC Merger Regulation sets out what the
Commission must take into account when establishing whether or not a concentra-
tion is compatible with the common market.^52 For example, the Commission may
take account of any substantiated and likely efficiencies that counteract the effects
on competition, and the potential harm to consumers.^53
The EC Merger Regulation also sets out how the Commission must decide:
Where the Commission concludes that the concentration notified does not fall
within the scope of the Regulation, it must record that finding by means of a deci-
sion.^54 Where the Commission finds that the concentration notified, although fal-
ling within the scope of this Regulation, does not raise serious doubts as to its
compatibility with the common market, the Commission must declare that it is
compatible with the common market.^55 Where the Commission finds that the con-
centration notified falls within the scope of this Regulation and raises serious
doubts as to its compatibility with the common market, it must decide to initiate
proceedings.^56
If the Commission has initiated proceedings, it may decide to: (1) declare the
concentration compatible with the common market;^57 (2) declare the concentration
compatible with the common market following modification by the undertakings
(^48) Article 2(2) of Regulation 139/2004 (EC Merger Regulation).
(^49) Recital 32 of Regulation 139/2004 (EC Merger Regulation).
(^50) Recital 2(3) of Regulation 139/2004 (EC Merger Regulation).
(^51) Recital 25 of Regulation 139/2004 (EC Merger Regulation).
(^52) Article 2(1) of Regulation 139/2004 (EC Merger Regulation).
(^53) Recital 29 of Regulation 139/2004 (EC Merger Regulation).
(^54) Article 6(1)(a) of Regulation 139/2004 (EC Merger Regulation).
(^55) Article 6(1)(b) of Regulation 139/2004 (EC Merger Regulation).
(^56) Article 6(1)(c) of Regulation 139/2004 (EC Merger Regulation).
(^57) Article 8(1) of Regulation 139/2004 (EC Merger Regulation).