(1) The competition authority shall, acting ex officio or upon application, institute proceedings. If so requested, the competition authority may ex officio institute proceedings for the protection of a complainant. Unless otherwise provided for by the specific provisions of this Act, the general provisions of the German laws relating to administrative procedures shall apply to the proceedings.
(2) Parties to the proceedings before the competition authority shall be:
1. those who have applied for the proceedings to be initiated;
2. cartels, undertakings, business and trade associations or professional organisations against which the proceedings are directed;
3. persons and associations of persons whose interests will be substantially affected by the decision and who, upon their application, have been admitted to the proceedings by the competition authority; the interests of consumer advice centres and other consumer associations supported by public funds are substantially affected also in cases in which the decision affects a large number of consumers and in which therefore the interests of consumers in general are substantially affected;
4. in the cases of Section 37(1) nos 1 or 3, also the seller.
(3) The Bundeskartellamt shall also be a party to proceedings before the supreme Land authorities.
(4) In addition to natural and legal persons, associations of persons without legal capacity shall also have the capacity to participate in proceedings before the competition authority.