Nope. You must have 12 owners to form a league. You can create a private league. All that means is that you have a password to enter the league so only the people with the password can join. All your friends join and then you can make a post in this forum and share the password with whoever you like to fill out the league.
Also, new for 2007, you can allow managers to own multiple teams in a league. So when creating the league, if you make that option yes, certain people can have 2 teams, if you still want it to be just you guys.