Exchange of Information on Request (EOIR)
Under the EOIR framework, all the double tax treaties (DTT's / DTA's) and tax information exchange agreements (TIEA's) are not working, unless a treaty state takes the initiative to make a request, which is foreseeably relevant to the administration or enforcement of its domestic tax rules, to another treaty state in accordance with the agreed upon procedures.
Under the AEOI framework, a reporting financial institution in state [A] will automatically disclose to its treaty state [B] the information about the bank accounts maintained with the reporting financial institution in state A and held by the tax residents of state B.
Spontaneious exchange of information
The provision of information to another contracting party that is foreseeably relevant to that other party and the information has not been previously requested. Because of its nature, spontaneous exchange of information relies on the active participation and co-operation of local tax officials (e.g. tax auditors, etc). Information provided spontaneously is usually effective since it concerns particulars detected and selected by tax officials of the sending country during or after an audit or other type of tax investigation.
Reference to EOI