Article 159 bis 1 mandates that any small enterprise claiming special tax status must proactively provide documentation to the Tax Authority. This includes data and information required to verify that the enterprise actually meets the capital, income, and employee conditions specified in Article 159 bis. These documents must be submitted within the timeframe specified by the Authority. This provision ensures that only legitimate small businesses benefit from the simplified regime and provides the Authority with the evidence needed to prevent larger entities from misrepresenting their status to reduce tax.