Does R&D expenditure volatility affect stock return?

The relation between the volatility of R&D expenditure and stock return may be influenced by disruptive adjustment costs, emerge from earnings management, or reflect the actions of managers attempting to control the overinvestment of technocrats. Using 5,178 publicly listed US firms from 1980 to 2018, we find a negative relation between R&D volatility and return, which is moderated by firm size. We conclude that investors react negatively to the disruptive effect of changes to R&D expenditure, except for small firms. In small firms, the benefit of the governance mechanism of varying R&D expenditure to control overinvestment outweighs the cost of disruption.