Prior to the approval of the Spanish transfer pricing law, Law 36/2006, effective from 1 December 2006, taxpayers were not subject to general documentation requirements for transfer pricing purposes. Therefore, there will be no specific court cases concerning transfer pricing documentation obligations. However, a few cases can be anticipated with regard to the valuation of transactions between related parties. Following the approval of Law 36/2006, it is expected that court cases dealing with transfer pricing documentation obligations will certainly arise.