Currently BlueMix only allows 'Members' of an organisation who have been delegated 'Manager' privileges the ability to add/remove users to the organisation.
Collaborators cannot add/remove users regardless of whether or not they are delegated 'Manager' privileges.
The distinguishing factor between a Member and a Collaborator is that a Collaborator already had a BlueMix account when they were invited to the Org, while a Member created their BlueMix account through an invite to the Org.
I see no reason to control who can add/remove users based on whether or not the Manager did or did not have an account with BlueMix before they were invited to the Org. If the user is delegated Manager privileges, they should be able to add/remove users to the org.
If this isn't resolved, users will need to create new BlueMix accounts for each organisation they want to work with as a manager. As a GBS consultant who works with a range of clients this is extremely frustrating. However I know that this is also an issue for other Non-IBMers who work with a number of different organisations - this will discourage them from recommending BlueMix to their clients or using BlueMix at all.
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