Such MAC’s serve to allocate risks between seller and buyer in case of material adverse changes in the inherent basis of the contract between signing and closing. If during this period – which often may last for several months – severe changes in the inherent basis of the contract occur, MAC’s allow the buyer to disengage from the contract or at least to renegotiate the main contents of the contract, in particular the purchase price. The use of MAC’s is advisable in particular in acquisition contracts which bear a relation to Germany and/or are governed by German law. Even though the German Civil Code contains a provision which offers the buyer possibilities to adjust the contract or to disengage from the  signed contract altogether in case of a change of the inherent basis of the contract” („Wegfall der Geschäftsgrundlage“), this provision is a general clause which can lead to considerable interpretation problems resulting in legal uncertainty when actually applied to a case at hand. The buyer should always try to include a MAC clause in the acquisition contract. The composition of the clause always depends on the case in question though. There are several different ways to structure such a clause. In order to agree on MACs in a useful way, it is important for the buyer that the main circumstances of the signing of the acquisition contract forming the inherent basis of the contract – such as, e.g., expected sales volumes or  profit margins - are clearly defined in the contract. It is also useful to include in the contract a provision as to who is authorised in the case of doubt to determine with binding effect whether the clause is triggered or not. It is therefore recommendable to include arbitration clauses in order to enhance legal certainty.