WhatsApp has updated its group chat settings to try and put more control in your hands. Now, when you go to Settings > Account > Privacy > Groups the options you have on who can invite you to a group chat are: “Everyone,” “My Contacts,” or “My Contacts Except.” On the latter you can exclude certain contacts from adding you to groups if you have that one friend who is a bit too new-group-trigger-happy.
Previously the “My Contacts Except” option was simply “Nobody”, but this left little granular control to you. That’s now changed.
In a blog post WhatsApp said that if someone you have added to the exception rule tries to invite you to a group chat, they will get a prompt to send you a private invitation to join, which you can then accept or decline within three days. Without this option, you are simply added to a group chat with no choice as to decline or accept.
This is a minor change, and you may well be fine with just leaving a group chat yourself if you don’t like it, which has always been possible and still is now.