Always a difficult moment for a trademark holder who introduces its trademark in foreign countries: when do you apply for your trademark abroad? Especially when you do not know whether it will be a success or which countries will apply, spending money on trademark protection sounds not very appealing. On the other hand, you do not want to be too late.
Pinterest , the digital pin-up board with nice pictures about anything and everything , was obviously too late : the company Premium Interest filed the trademark PINTEREST in the European Union, 2 months before Pinterest filed its US trademark.
This appication by Premium Interest was done in good faith, so Pinterest could only base the opposition (which it filed against this application) on the basis of unregistered trademark rights. But you have to proof that such rights exist in local trademark law. In the Netherlands/Benelux, for example, the trademark law does not provide this ground. Bottom line in this case is that this ground was only attested for the UK and not for the other countries.
A second difficulty is that you must be able to prove that there is a right of more than local significance. This evidence had to be dated before early 2012 in this case. This is always a difficult task even in case of a rather well known trademark as Pinterest. Since the OHIM systematically rejected all the evidence as the evidence concerned the use of the mark in the US and not in the UK, Pinterest lost the opposition.
So, the lesson is you better be safe than sorry!