There is a minimum number (six, I think), but there's also a two-year waiver if you temporarily drop below. I think the idea is something like WSU and OSU play each other for a "pac 2" championship for a year or so, and play a mostly MWC slate of non-conference games. Then, after the MWC media deal expires in 2025 that whole league's membership would join the Pac. In the meantime, OSU and WSU would make their budget by splitting the existing Pac's NCAA tourney and CFP payouts two ways. It's a genius plan, really. Still, after 2026 I don't know what media payout the new Pac 14 would be worth, or whether they could maintain a full CFP payout; I doubt the latter part especially. Personally I'd let them do it, let them keep the money for now, and just treat them in future CFP arrangements as the MWC is treated now (including going down from 6 spots for conference champions to 5). Changing the arrangements right now requires unanimous agreement, but when the contract is renewed after 2026 it's all going to be made from scratch. They'll sign on to what they're offered because they have no choice.