Does GitHub have to pay a fee to use Git in their name?
> The USPTO initially rejected our application as confusingly similar to the existing trademark on GitHub, which was filed in 2008. While one might imagine where the "Git" in GitHub comes from, by the time we applied to the USPTO, both marks had been widely used in parallel for years. So we worked out an agreement with GitHub which basically says "we are mutually OK with the other trademark existing".