The European Court of Justice ruled in favour of the French luxury brand after it sought to prevent Dutch high street chain Van Haren from selling its own versions of high-heeled shoes with red soles.
Its ruling centred on whether the red soles should be considered to consist exclusively of a "shape" - in which case it would not have been entitled to trademark protection.
Louboutin had brought the case in the Netherlands after Van Haren began selling its red-soled shoes in 2012, and a district court in The Hague referred it to the ECJ.
Judges rejected the official advice of the ECJ's advocate general, who had said the soles should not be trademarked.
They ruled that in this case the mark at issue "does not relate to a specific shape of sole for high-heeled shoes".
The "shape" was simply the outline for showing where the colour was located on the bottom of the shoe, the court found.
Having had this point of law settled, the case now returns to the Dutch court for a final judgment.
Founded in 1991 Louboutin, whose footwear typically retails for more than £500, is a high-end fashion favourite made popular by celebrities including the stars of Sex and the City.
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The company welcomed the judgment, saying in a statement: "The protection of Christian Louboutin's red sole trademark is strengthened by the European Court of Justice."
In 2012 it won a similar case in the US.