The decommissioning, preparation (by the unit operator) and approval (by the unit`s operating committee) of the dismantling work programme and budget remain largely unchanged. Decommissioning is an area in which the provisions of AIPN-UUOA 2020 may not be useful under a single specific scheme. The decommissioning rules in an UUOA should normally be linked to the obligations of the dismantling of the groups in their underlying contracts – which may be different. Once the initial wing holdings are calculated, the interest of each party is determined by the multiplication of the percentage of the party under its licence by the initial participation in the wing for that licence. AIPN UUOA 2006 looked at preliminary unit expenditures by giving contract groups the opportunity to reallocate the costs borne by each group prior to the transaction, so that the costs are shared by the groups based on their respective shares in the unit. AIPN-UUOA 2020 expands pre-unit rules to take into account the redistribution of production from the unit prior to the introduction. It is rare for production to start from one unit area prior to the introduction, but the situation can occur when a group begins to produce hydrocarbons from its contract territory without knowing that the reservoir is overflowing to another contracted area. The concept of unity comes from the United States. At the beginning of the 20th century, the concept of unity did not exist, but the concept of “capture rule” was applied.
An agreement of agreement contains provisions on when a redefinition should take place, including limiting the number of new provisions that can take place. However, certain unitation agreements (including some UKCS unification agreements) applicable to much smaller discoveries will determine market participation and equity interest, so that they are not subject to redefinition, since the cost of redefinition would amount to devaluing all the merits of redefining market participation. Given the importance of the new provisions and in order to ensure the integrity of the process, letters of commitment to the expert may provide a guarantee that the expert has not conducted a study on the relevant area for one of the parties to the single agreement before a certain period of time and that the expert has no conflict of interest with the parties. The share/unit interest of each party determines each party`s expenditure commitment on unit costs, the right to hydrocarbons and voting rights for matters governing the unit. To combat this situation, the concept of unity was developed in the United States and then adopted by the IOCs in a number of other jurisdictions, including the United Kingdom. The participation of each contract group (i.e. its share of the unit` share) determines the group`s right to benefit from hydrocarbons produced from the unit and its share of unit costs.