Joining a free company?

My friend was trying to invite me to their free company, but it wasn't working. I thought there might have been a level requirement, but I just saw a level 4 in one? Is there some sort of secret something I have to unlock before I can join them? The button is grayed out in my main menu.

did you accept the invite? you may have to right click the FC and select accept invite

i'm having the exact same issue on the ps3. Did you figure it out?

I know you need 3 people to create a FC, but what happens if 2 of them leave? Is your FC dismantled?