Verification on emissions data intends to ensure the consistency of information, and to identify any potential errors in the aeroplane operator’s annual Emissions Report.

CORSIA foresees a three-step verification pathway:

· At Step 1, a voluntary internal pre-verification by an aeroplane operator is recommended. This means that the aeroplane operator conducts a verification of its data before submitting it to a third-party verification body. The internal pre-verification is likely to increase the quality of the Emissions Report, but it does not replace the requirement for third-party verification.

· At Step 2, a third-party verification is performed by an independent thirdparty verification body, before the operator reports to the State Authority. The requirements for the third-party verification will be based on existing Standards from the International Organization for Standardization (ISO), as well as on CORSIA-specific requirements from Annex 16, Volume IV. A third-party verification body is contracted by an aeroplane operator.

· At Step 3, the State Authority conducts an order of magnitude review. This is the check performed by a State to verify the data against different sources of information that the State has access to.