If two joint account holders do not agree on a disclosure option for an account, and the account has no disclosure option set, can the account holders still share data from that account, by both approving the authorisation to share?
The existing rules do not allow any joint account data to be shared unless all joint account holders agree to apply a disclosure option (i.e. 'opt-in'). An authorisation cannot be 'co-approved' where no disclosure option has been applied.
You may be aware that the joint accounts model is being revisited in a joint Treasury/DSB consultation. This outcome of this revision may have some bearing on this question.