2.16 Intangible assets
Intangible assets comprise rights, licences and software. They are valued at acquisition or production cost less accumulated depreciation and impairment. The acquisition cost of rights, licences and software comprises the purchase price plus directly attributable costs. Rights, licences and software are amortised using the straight-line method over the contractually agreed duration. Software developed in-house is amortised using the straight-line method over a maximum period of three years.