Technically the .ttf file could be copyright as a specific means to reproduce the typeface, but someone could just run it through something to copy the shapes and then there’s nothing to be licensed.
Japanese law doesn’t consider font itself or the style to be copyrighted, but font files are considered “program” (it is very broad in jurisdictional sense, roughly translates to “digital data that produce products through computational process”, and displaying letters on monitor is applicable) and thus fall under under copyright protection.
What is this even licensing? You can’t copyright a typeface in Japan or the US: https://en.wikipedia.org/wiki/Intellectual_property_protection_of_typefaces#Japan
Technically the .ttf file could be copyright as a specific means to reproduce the typeface, but someone could just run it through something to copy the shapes and then there’s nothing to be licensed.
Japanese law doesn’t consider font itself or the style to be copyrighted, but font files are considered “program” (it is very broad in jurisdictional sense, roughly translates to “digital data that produce products through computational process”, and displaying letters on monitor is applicable) and thus fall under under copyright protection.