Artikel 5

1. Each Contracting State shall take such measures as may be necessary to establish its jurisdiction over the offences in the following cases:
(a) when the offence is committed in the territory of that State;
(b) when the offence is committed against or on board an aircraft registered in that State;
(c) when the aircraft on board which the offence is committed lands in its territory with the alleged offender still on board;
(d) when the offence is committed against or on board an aircraft leased without crew to a lessee who has his principal place of business or, if the lessee has no such place of business, his permanent residence, in that State.
2. Each Contracting State shall likewise take such measures as may be necessary to establish its jurisdiction over the offences mentioned in Article 1, paragraph 1 (a), (b) and (c), and in Article 1, paragraph 2, in so far as that paragraph relates to those offences, in the case where the alleged offender is present in its territory and it does not extradite him pursuant to Article 8 to any of the States mentioned in paragraph 1 of this Article.
2 bis. Each Contracting State shall likewise take such measures as may be necessary to establish its jurisdiction over the offences mentioned in Article 1, paragraph 1 bis, and in Article 1, paragraph 2, in so far as that paragraph relates to those offences, in the case where the alleged offender is present in its territory and it does not extradite him pursuant to Article 8 to the State mentioned in paragraph 1 (a) of this Article.
3. This Convention does not exclude any criminal jurisdiction exercised in accordance with national law.