104 It is sometimes claimed that the registration of an instrument under Article 102 of the United Nations Charter indicates that it is an international treaty. However, this is not a reliable indicator, since the United Nations secretariat, on the one hand, records almost all the documents submitted to it, including unilateral declarations, and that, on the other hand, not all contracts are registered. This is also the view of the ICJ in the case between Qatar and Bahrain: in 1994, when non-registration was not determinative of the character of the document in question (situation 122). 70 In addition, a contract may be modified by the subsequent and uniform practice of all its parties. A well-known example is Article 27, paragraph 3, of the United Nations Charter, which concerns the vote in the UN Security Council. Despite the terminology of a „japtive vote of nine members, including the converging votes of permanent members“, a subsequent practice has developed, whererly the abstention of a permanent member, which must be distinguished from a negative vote (veto), does not prevent the adoption of a resolution. In its legal opinion Legal consequences for states of South Africa`s continued presence in Namibia (South-West Africa), notwithstanding Security Council Resolution 276 (1970) (Advisory Notice) („Legal Consequences of South Africa in Namibia“), the ICJ found that this practice had been generally accepted by UN member states. 88 The ICJ has always complied with the interpretation of the text as the most important, as in the territorial case (Libyan Arab Jamahiriya/Chad), in which it stated: „Interpretation must first and foremost be based on the text of the treaty. As a complementary action, interpretation means such as preparatory work can be used.“ The definition of the ordinary meaning of the concept is done within the framework of the treaty as a whole and in the light of its purpose and purpose (see for example.B. Interpretation of the 1919 Convention on the Employment of Women at Night [Advice Notice] PCIJ Series A/B No. 50).
92 One of the most controversial topics in the interpretation of the treaty is the use of preparatory work (preparatory work). The VCLT sets out very specific conditions in which preparatory work can be used: either to confirm the meaning of the contract or as an interpretive medium, when, after application of art. 31 VCLT, the meaning is opaque or results in a patently absurd or unreasonable result. The ICJ has always used preparatory work in a very restrictive way. However, this approach has led to the view that the ICJ has not always sufficiently defined the necessary common intention of the parties (see the 1995 maritime and territorial boundary issues between Qatar and Bahrain [Qatar/Bahrain] [Vice-President Schwebel`s derogatory notice]); Case between Qatar and Bahrain ). 68 In the VCLT, the concept of „amendment“ refers to treaty changes between all parties, while „amendment“ only concerns changes between certain parties (intersynemes), a distinction that is relevant only in the context of multilateral treaties (s. 39-41; Treaty, amendment and revision). The VCLT does not use the term „revision“ of contracts, based on the ILC`s view that, prior to the Second World War, certain „nuances“ were added to it (comment in Article 35, draft articles of UN ILC on the Law of Comment Contracts“  GAOR 21st Session Supp 9, 20).