The red sole of Christian Louboutin’s exquisitely crafted heels is a sign of luxury the world over. But recently three European countries ruled it’s not an exclusive one. According to Simon Frankel and Aysha Qureshi of Covington & Burling, the trademark on the red sole has been declared void in Belgium, the Netherlands and Luxembourg by the Brussels District Court.

The trademark is “one of the most litigated intellectual property rights in the fashion industry in recent years,” they say. The company brought a case against a Netherlands-based shoe company for infringing on the sole, but the Brussels court ruled it couldn’t be trademarked under European law. Frankel and Qureshi explain the decision was based on the judge determining it was a shape mark versus a color mark, and under European trademark law, if a shape gives substantial value to goods, it cannot be registered. This prevents “a company monopolizing a technical, functional or aesthetic quality,” they say.