The issue of what a trademark is and what is its legal definition was discussed in the previous parts of this series (You can read it here).
A trademark which constitutes a color is a mark composed of only one color (per se) or a combination of colors without the outlines.
This kind of trademarks shall be represented by a reproduction of color or a combination of colors without marking the outlines, which reproduction shall demonstrate in a uniform and predetermined way their regular arrangement, along with the indication of colors by referring to the generally accepted code of colors ? for example the PANTONE color identification system.
It is also important that an application for registration of a color or a set of colors as a trademark includes a description of the mark indicating the position of colors and their proportions.