So I have 2 ideas, both listed below.
1. I think that in your profile, if your in a clan it should show how long you've been in it.
2. I think if your look at your profile/another profile there should be a new section called "Clan History" this is where you can go and look to see how long you/the person your looking at were in there previous clans. This woul help to be sure the person you are inviting to your clan is loyal or not.




