1. The national regulatory authority must ensure that the prohibitions set out in Articles 3 and 5 and the obligation set out in Article 4 are applied.

The national regulatory authority must exercise its investigatory and enforcement powers in a proportionate manner.

Those powers may be exercised:

(a) directly;

(b) in collaboration with other authorities; or

(c) by application to the competent judicial authorities.

Where appropriate, the national regulatory authority may exercise its investigatory powers in collaboration with organised markets, trade-matching systems or other persons professionally arranging transactions as referred to in point (d) of Article 8(4).

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