(11)To ensure proper implementation of the requirement to determine whether the principal trading venue of a share is located outside the Union, transitional arrangements should be put in place for determining for the first time the list of exempted shares under Article 16 of Regulation (EU) No 236/2012. In addition, although the list of exempted shares is effective for a two year period, it is necessary to provide some flexibility as there are cases where a review of that list might be necessary during the two-year period.