O2 Holdings Ltd v Hutchison 3G UK Ltd Case C-533/06 [2008] All ER (D) 155 (Jun)
Article 5 of Council Directive 89/104/EEC (trade marks) and Art 3a(1) of Council Directive 84/450/ EEC (misleading and comparative advertising) (the Directive) must be interpreted to the effect that the proprietor of a registered trade mark is not entitled to prevent the use by a third party, in a comparative advertisement, of a sign similar to that mark in relation to goods or services identical with, or similar to, those for which that mark was registered where such use does not give rise to a likelihood of confusion on the part of the public. That is so irrespective of whether or not the comparative advertisement satisfies all the conditions laid down in Art 3a of the Directive.