"17. ... I regret that the ECJ in this case has not addressed the competition aspects of what it calls "riding on the coattails". The trouble with deprecatory metaphorical expressions such as this ("free-riding" is another), containing as they do clear disapproval of the defendants' trade as such, is that they do not provide clear rules by which a trader can know clearly what he can and cannot do.
I do not stand alone. For instance [Darren] Meale and [Joel] Smith wrote this in the Journal of Intellectual Property Law Practice (2010) Vol 5, 96 at 103:
While the ECJ's conclusion largely condemns the practices of the defendants in L'Oréal, it does so without providing clear guidance as to where the line is drawn between unfair and fair advantage. It might be read to suggest that all advantage is unfair. This would render the word 'unfair' in the article redundant, as was Jacob LJ's concern when he reviewed the previous free-riding authorities in the Court of Appeal".