Article 53
1. Without prejudice to the limits laid down in Article 56, Member States may raise the limits laid down in Article 52 to a maximum of 20 % for investment in shares or debt securities issued by the same body when, according to the fund rules or instruments of incorporation, the aim of the UCITS' investment policy is to replicate the composition of a certain stock or debt securities index which is recognised by the competent authorities, on the following basis:
(a) its composition is sufficiently diversified;
(b) the index represents an adequate benchmark for the market to which it refers; and
(c) it is published in an appropriate manner.
2. Member States may raise the limit laid down in paragraph 1 to a maximum of 35 % where that proves to be justified by exceptional market conditions in particular in regulated markets where certain transferable securities or money market instruments are highly dominant. The investment up to that limit shall be permitted only for a single issuer.