Higher country taxes on noxious manufacturing emissions lead to substantial increases in firms’ R&D spending. The R&D response is entirely driven by those high-pollution firms most affected by emissions taxes. Pollution taxes increase the marginal value of R&D spending in polluting firms, even when this spending does not lead to new innovation. Pollution taxes have the strongest effect on R&D investment in sectors in which new invention is difficult to appropriate and outside knowledge is easier to acquire, suggesting an important reason dirty firms invest in R&D is to expand their capacity to absorb external knowledge and technical know-how.

Sweden was one of the first countries to introduce a carbon tax back in 1991. We assemble a unique data set tracking CO2 emissions from Swedish manufacturing firms over 26 years to estimate the impact of carbon pricing on firm-level emission intensities. We estimate an emission-to-pricing elasticity of around two, with substantial heterogeneity across subsectors and firms, where higher abatement costs and tighter financial constraints are associated with lower elasticities. A simple calibration suggests that 2015 CO2 emissions from Swedish manufacturing would have been roughly 30% higher without carbon pricing.