(a) does not make use of the authorisation within 12 months, expressly renounces the authorisation or has ceased the activity covered by this Directive for the preceding 6 months, unless the Member State concerned has provided for authorisation to lapse in such cases;
(b) obtained the authorisation by making false statements or by any other irregular means;
(c) no longer meets the conditions under which authorisation was granted;
(e) has seriously or systematically infringed the provisions adopted pursuant to this Directive; or
(f) falls within any of the cases where national law, in respect of matters outside the scope of this Directive, provides for withdrawal.