So today in class, I actually learned that the Japanese game company "Sega"'s name is actually written in Katakana, not Hiragana. I learned the same also applies to some other notable companies, such as Toyota and Honda. But it seems there are also companies that don't have katakana names, such as Mitsubishi.
Is there any way to tell right off the bat whether or not a Japanese company's name is in hiragana or katakana? When I asked my teacher, she mentioned it might have something to do with how famous or popular the company may have been.