23.9. Best possible use of available data sources. In the absence of customs records, the use of national registers for ships and aircraft is the established practice in many countries. Countries need to review the contents and completeness of their national registers (including their law of the flag etc.) and they might use available international registers and special surveys of ship and aircraft operators to identify economic ownership and change of economic ownerships for ships and aircraft. Relevant information could also be available from accounts of companies and from the review of leasing contracts or management contracts (for vessels). However, it appears that countries are not availing themselves at this time of the option of reviewing leasing contracts or agreements on the management and operation of ships and aircraft to determine economic ownership.
23.10. Need for reliable criteria to identify change of ownership. Countries should establish reliable criteria for the identification of change of economic ownership of ships and aircraft and provide information in this regard in their metadata. On the national level, such criteria should be established in cooperation with national accounts and balance-of-payment compilers. However, an international approach and agreement on such criteria are required in order that uniform treatment of transactions and international comparability of data may be achieved. For example, reliable criteria could be established in the form of a list of different types of leasing contracts and agreements on the operations of the ships and aircraft, to be analysed in respect of whether they entail a transfer of risks and rewards, as required for change of economic ownership. For aircraft, leasing plays a predominant role, while for vessels, different kinds of agreements concerning their operation and management are relevant.
23.11. An international approach regarding the identification of change of ownership and the recording of trade in ships and aircraft. International cooperation and the development of a common approach and common criteria for the identification and recording of change of ownership offer possibilities for improving the statistical recording of trade in ships and aircraft. For example, as a first practical step, countries could pool and compare their information on major transactions using universal ship or aircraft identification or production numbers. However, countries might not have sufficient access to such information on national level or it might be preferable for other reasons to follow the existing national approach.
23.12. Conclusions. The task of compilers of merchandise trade statistics is to identify non-reported transactions and to verify reported transactions. The development of a more comprehensive set of case studies, as currently conducted by Eurostat, can assist countries in performing this task.
 In the case of ships, the flag administrations (national registers) establish a regular and standardized electronic data exchange procedure with HIS Fairplay on a fleet basis which includes data not only on the company/registered owner but also on the ships. The information is made available toIMO members on the Global Integrated Shipping Information System (GISIS).
 Eurostat, “Methodological questions from member States relating to the trade in ships and aircraft”, internal document, 28 November 2011.