Their evaluations aren’t company based. There are girls on the show from the same company, even from the same idol groups, who are part of separate evaluations
For example, Ahn Jungmin & Guinn Myah are both under TOP Media, yet performed seperate songs. Same with Kim Dayeon & Sakamoto Shihona who are both under Jellyfish, and more
A lot of them come from top companies, but those companies don’t be specified. It’ll go to show they’ll need more than company relevancy to make it far enough
