Article 16 bis mandates that all government entities, public institutions, and state-owned companies (with >40% ownership) must verify a taxpayer's status before contracting or transacting. Taxpayers must provide a valid copy of their tax card, which the government body must stamp and include in the transaction file. If a taxpayer fails to provide the card, the government entity is obligated to notify the Tax Authority, explaining the reasons for non-submission within the timeframe specified by the Executive Regulations. This integrates tax compliance directly into the public procurement and administrative process.