Complex sentence: Except on the railways CIÉ is not a complete monopoly, as a number of other operators exist, but under the Transport Act 1932 they cannot compete directly with CIÉ on route for which it has a licence.
Split into simpler sentences: Except on the railways, CIÉ is not a complete monopoly, as a number of other operators exist. However, under the Transport Act 1932, such other operators cannot compete directly with CIÉ on route for which it has a licence.