【摘要】 企业成本加成率是以成本为基础衡量盈利能力的重要指标，是企业竞争力的综合体现。以2009—2020年沪深A股上市公司为研究对象，运用双重差分模型及中介效应模型，分析营改增税制改革对企业成本加成率提升的政策效应及作用路径，研究发现：营改增税制改革对企业成本加成率具有显著促进作用；企业研发投入在营改增税制改革对企业成本加成率的提升作用中发挥了中介效应，即营改增税制改革通过增加企业研发投入能够显著提高企业成本加成率；进一步基于企业异质性研究发现，与国有、大规模和成熟企业相比，非国有、小规模和年轻企业的营改增税制改革通过增加企业研发投入提高企业成本加成率的提升效应更加显著。研究结论为进一步完善增值税抵扣链条，规范税收征管行为，促使不同性质企业及时把握政策红利、提升创新能力、增加企业价值等提供理论依据。更多还原

【Abstract】 Enterprise markup is an important indicator of profitability based on cost, which is a comprehensive reflection of enterprise competitiveness. This paper analyzes the policy effect and the path of effect of tax reform on the increase of enterprise markups by using difference-in-difference model and mediation effect model for the research objects of A-share listed companies in Shanghai and Shenzhen from 2009 to 2020, and finds that: Tax reform have a significant promotion effect on enterprise markups; Enterprise R&D investment plays a mediating role in the increase of enterprise markups by the tax reform, which means that the tax reform can significantly increase the enterprise markups by increasing enterprise R&D investment; Further research based on corporate heterogeneity finds that the positive effect of tax reform on corporate markups through increasing corporate R&D investment is more significant in non-state, small-scale and young corporate groups compared to state-owned, large-scale and mature corporate groups. The findings of the study provide a theoretical basis for further improving the value-added tax deduction chain, standardizing tax collection and management behaviors, and prompting enterprises of different natures to grasp policy dividends in a timely manner, enhance innovation capabilities, and increase corporate value.更多还原