|Spoiler Alert: This page contains spoilers. Read at your own risk.|
It has been indirectly implied that Aoba still has great influence over the Yotsuba Family because he created the Fourth Research Institute, and is still supporting the Yotsuba Family.
The Sponsor is an independent non-governmental group or individual said to have strong power and influence among nations.
The current sponsor created the Fourth Research Institute, and it is rumored that it began operating before AD 2020, meaning the sponsor was established before the 10 Research Institutes were recognized and created.
- The First Mention: The sponsor of the 4th Research Institute was first mentioned during a conversation between Yotsuba Maya and Hayama, as they were discussing about obtaining one of the Parasites for research. Hayama expressed concern that obtaining a parasite may bring discord with the Sponsor (calling them "those creatures"). However Maya replied that obtaining a parasite is necessary for the Yotsuba Clan, and that she doesn't want to bring discord with the sponsors because they are very important. 
- The Second Mention: The sponsor was again mentioned during another conversation between Maya and Hayama, where they were discussing about the sponsor's intention and plans to destroy the Anti-Great Asian Union group.