The deduction for patent income applies since the tax year 2008.

Are taken into consideration: the patents or supplementary protection certificates registered by the company itself and that have been developed, wholly or partially, in the R&D centres of the company, as well as the patents, supplementary pro­tection certificates or licences acquired by the company provided they had been improved in the R&D centres of the company.“Patent income” means as well the income stricto sensu notably derived from the granting of licences, as the income which would have been received from a third party by the company having exploited patents on its own behalf. The income must be assessed on the basis of the remuneration which would have been agreed be­tween independent companies.The qualifying income must be included in the taxable income and the following expenses must be deducted:• amortisation charge for the taxable period, on the investment value or cost price of the patents, provided it is deducted from the basic amount which is taxable in Belgium;• compensation owed to third parties pertaining to these patents, deducted from the taxable result in Belgium.The thus determined income enjoys an 80% exemption. In case of insufficiency of profit, the balance of the deduction for patent income cannot be carried over to the next taxable periods.