This licence gives a monopoly to perform investigations, exploration drilling and recovery of petroleum deposits within the geographical area stated in the licence. The licensees become owners of the petroleum that is produced. A production licence may cover one or more blocks or parts of blocks and regulates the rights and obligations of the participant companies with respect to the Government. The document supplements the provisions of the Petroleum Act and states detailed terms for the individual licences. Exploration period: At the outset, the production licence is awarded for an initial period (exploration period) that may last up to 10 years. In this period, the licensees are obliged to carry out specific tasks, such as seismic surveying and/or exploration drilling. If these mandatory tasks are fulfilled within the exploration period, the licensees may, in principle, demand to retain up to half the area covered by the award for up to 30 years.