MS in domain name

Just bought a top domain regarding the new kin phone. Now it has MS in the domain name.

Shouldi start to save up some cash like you have to do when you have apple in your domain?

Well if it has a MS trademark in it, then there isn't much you can do. It's the price you pay when you decide to register trademarked domains. So either monitise it best that you can until the ask for you to hand it over or let the registration lapse.