Really all you have to do is look up either Viacom or CBS in a search engine. Both articles will tell you how Paramount was divided between them when the two companies went their separate ways in 2006 and who got what.I wish people claiming that CBS owns something would cite a source supporting their assertion.
But you'll also find that essentially everything Trek after 2006 is either solely or partially copyrighted by CBS. Even this website has to acknowledge CBS as owning the copyright to Star Trek at the very bottom of the page.