A T-shirt vendor on etsy.com recently received a cease and desist from a trademark owner, who had received a UK trademark for BITCOIN. The trademark BITCOIN covers a huge list of clothing and other goods, and has been registered since April 2018. The Bitcoin community is up in arms over this shameless attempt to monopolize a very common word, and get a head start on brand recognition. However, this is not the first time this has happened in a derivative field, especially in t-shirts, and the trademark may be enforceable against certain T-shirt vendors.
First of all, it should be noted that the trademark holder cannot stop BITCOIN from being used for digital cryptocurrency. This would be descriptive, and this BITCOIN is not trademarked as such. However, it is possible to repurpose words to be used in a new way, like on clothing and other articles that are not related to cryptocurrency and the buying and selling of cryptocurrency, which is why the UK trademark office registered the name for T-shirts and other clothing.
It is highly likely that BITCOIN appeared on shirts long before the trademark owner filed for the mark, so the BITCOIN registered mark could potentially be invalidated by these users. In any event, the subsequent registration cannot prevent the earlier users from using the mark, however. in the US, they might be limited in region to where they had sold previously.
Several years ago, a similar situation occurred in the area of T-shirts, wherein a person trademarked the symbol PI for use on T-shirts in the US. There were some lawyer’s letters sent back and forth, but I don’t recall if a case was ever filed. In any event, it appears the trademark owner was unsuccessful because the PI T-shirts continue to be sold in numerous location in the US. The owner in that case was not the first and would not be able to prevent an earlier user.