I tried to tag a post "Flint's", and I got "flint" and "s" instead. I tried to delete the tags and enter "flints", but Stack Exchange says it's too close to "flint" and won't let me do it.
I guess that after that period, you could create a flints tag, but should you? A tag for a single brand is IMHO much too narrow; I couldn't find a precedent for this (but maybe, as a Dutch person, I don't recognize a brand). This is what the Help Center says about creating tags:
When should I create new tags?
Most common tags already exist on a mature site. You should always favor existing tags; only create new tags when you feel you can make a strong case that your question does cover a new topic that nobody else has asked about before on this site.