MSY Founder is a blanket term used to refer to one of the roughly 24 girls who formed the original MSY. As such, they would have been a member of one of the 6 Magical Girl Teams that signed the original MSY Charter. In order of signing, the six teams are listed below, along with known members:
- Mitakihara Four
The core founding team, this team contains all the living magical girl members of the original cast, plus Chitose Yuma from Oriko Magica. Miki Sayaka was a member of this team, but died before the founding. Unlike the other team names, "Mitakihara Four" is still in common usage by the time of the Contact War, and it is the only team with a complete member list.
- University Area Group
This team was apparently located in the vicinity of Mitakihara University, and may have contained students of the school. They collectively ran a food stand to garner extra funds.
- Northern Group
- Financial District Group
This team once had a member captured and killed by Oriko of the Southern Group.
- Factory Area Group
- West Kazamino Three