I hope this is the correct community for my question (I am just a humble data scientist, not a designer).
I am building a powerpoint presentatin that should contain a lot of plots, each consisting of 2-4 curves on a white background. I am thinking about using some colors of the Paris undergroud map for my plots because they are bright, work well together and look fine on white background. Unfortunately, I can't find any information whether these colors -- by this I mean the specific set of color codes -- are protected by some kind of copyright.