The relevance of copyrights and internet domain names

Just a hypothetical question. Supposing someone could register a domain name like MacDonald.com.sg, and MacDonald writes a polite letter to ask him not to use it, change it, does he need to comply? This is only a hypothetical situation. It can apply to any domain name.

Or would MacDonald call the owner of such a domain name and negotiate to buy it over as a business transaction? If I am not