The super-deduction of research and development (R&D) expenses is at the core of the policy to stimulate enterprise innovation in China. This paper identifies whether firms are supported by the super-deduction policies for R&D expenses and uses the difference-in-differences method to investigate the impact of the policies on R&D investment. The results show that changes in policy in 2013 significantly increased the R&D investment of firms engaging in key state-supported technologies. Policy changes in 2016 significantly increased the R&D investment of firms engaging in non-key-state-supported technologies. Enterprises not only invested all their tax incentives in R&D activities but also increased their investment in self-raised funds. The super-deduction policy had different impacts on different industries, firms with different boards, and firms with different ownership. The policy significantly affected the manufacturing and construction industries, the Small and Medium Enterprise Board, and non-state-owned enterprises. Through a mechanism analysis, we found that the policy significantly reduced the user cost of R&D and increased the net cash flow of enterprises, which could raise a firm's R&D investment. It is necessary to increase policy support, expand the scope of super-deductible expenses, and increase the super-deduction rate based on industry classification according to the sensitivity of different industries to the policy.

中文翻译：

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研发费用加计扣除能否拉动研发投入？

研究开发费用加计扣除是我国激励企业创新政策的核心。本文识别了企业是否受到研发费用加计扣除政策的支持，并利用双重差分法考察了政策对研发投入的影响。结果表明，2013年政策的变化显着增加了国家重点支持技术企业的研发投入。2016年政策变化明显加大了国家非重点支持技术企业的研发投入。企业不仅将税收优惠全部投入到研发活动中，还加大了自筹资金的投入。加计扣除政策对不同行业影响不同，拥有不同董事会的公司和拥有不同所有权的公司。该政策对制造业和建筑业、中小企业板和非国有企业影响较大。通过机制分析，我们发现该政策显着降低了研发的使用者成本，增加了企业的净现金流，从而提高了企业的研发投入。要加大政策支持力度，扩大加计扣除范围，根据不同行业对政策的敏感程度，按行业分类提高加计扣除比例。通过机制分析，我们发现该政策显着降低了研发的使用者成本，增加了企业的净现金流，从而提高了企业的研发投入。要加大政策支持力度，扩大加计扣除范围，根据不同行业对政策的敏感程度，按行业分类提高加计扣除比例。通过机制分析，我们发现该政策显着降低了研发的使用者成本，增加了企业的净现金流，从而提高了企业的研发投入。要加大政策支持力度，扩大加计扣除范围，根据不同行业对政策的敏感程度，按行业分类提高加计扣除比例。