Tax incentives and firm size : effects on private R&D investment in Spain

The use of fiscal policy instruments to stimulate private R&D is widespread and important in some countries like Spain. In this paper we explore the effectiveness of R&D tax incentives on knowledge capital accumulation in Spanish manufacturing firms using an unbalanced panel and compare the estimates based on claimed and claimable tax reductions. We find that while large firms use the programme more than small ones, the impact of the programme measured by the price elasticity is smaller for large firms than for SMEs. The price elasticities are higher when the ex-ante claimable tax reductions rather than the ex-post actually claimed tax eductions are used to compute the user cost of R&D.