I would categorize this as an emphasis word because it could be written in Hiragana but they want to "emphasize" that it is a company name, so they write it in Katakana. Also, I have come across ゲロゲロwhich is an onomatopoeia as seen below:
For the most part, the only unusual Katakana words that did not seem to fit into the three criteria were generally names (i.e. scientific names or company names). The rest of the unusual Katakana words seemed like they were not emphasis or loan words because it is difficult to identify them in Hiragana or a foreign language other than English. I believe Katakana words are used differently depending on who is using them. Now that it is gradually becoming a common practice to use Katakana, that is why there are slightly different criteria for the use of Katakana words.