In the case C-541/18 of the Court concerning a preliminary ruling according to article 267 TFEU a hashtag (#) was subject of a request for a preliminary ruling.
The sign #darferdas? was filed with the German Patent and Trademark Office as a mark for goods in the class 25, namely “clothing, in particular T-shirts; footwear; headgear“. The German Patent and Trademark Office rejected the trademark application due to any distinctive character; this was appealed by the applicant. The German Federal Court of Justice preferred to the Court with a referral.
The Court hold under no. 18 of the judgement that it cannot a priori excluded the design comprising a hashtag is capable of distinguishing the goods and/or services as coming from a particular undertaking. Therefore, a hashtag can satisfy the condition to be distinctive and can serve as a trademark.
Under point 19 of the judgment, however, the Court hold that such signs have to be proven for distinctive character. As in earlier rulings, the Court stated that the assessment of the perception of the average consumer must be carried out in concreto, taking into consideration all the relevant facts and circumstances. In case the sign has not been used in the economic sector, besides to the probable presentation to the average consumer other uses are maybe practically relevant, then such uses have to be examined. By a contrast, possible, but practically not relevant and therefore unlikely uses do not need to be considered in the examination.
Summing up, it follows, that for signs comprising a hashtag, but generally for all marks it can be referred to all possible uses and labels of a sign, if more uses of the signs are possible like in the instant case as a tag or as printing on, for example, a T-shirt.