I was once co-head of a tech company that had an "i" in the title. Like a bajillion other companies our logo was basically just the company's name in a particu

I was once co-head of a tech company that had an "i" in the title. Like a bajillion other companies our logo was basically just the company's name in a particular font and we turned the dot above the "i" into a little circle in a different colour. So far so not very surprising. A few months in we got a cease-and-desist from a company who claimed (and I'm not making this up) to have a trademark on the idea of making the dot of an "i" into a little circle in a different colour, and said that the trade dress of our logo was infringing because their logo was just their company name in a (different) font with the dot on the "i" being a circle in a different colour. I wrote back and asked them to clarify that it was their contention that that was a trademark and making it very clear I would fight it and we had no intention of changing anything. They disappeared. It's really important not to feed this nonsense by caving to the trolls.