This paper studies the role of the tax on mobile capital in labor markets with matching frictions and the effects of such frictions on inefficiency of capital taxation. Firms acquire capital and create vacancies, and workers apply for firms. Due to matching frictions, vacancies may not be filled, and workers may not be employed. Firms’ investment in capital, wages and market tightness are determined in a way that a firm’s profit and a worker’s utility are jointly maximized. In addition, the return to capital net of the tax is equalized across jurisdictions, as capital moves between jurisdictions. An increase in the capital tax of a jurisdiction alters firms’ capital investment, wages and market tightness of the jurisdiction. In particular, it decreases employment and wages of the jurisdiction, providing an explanation for why policymakers of a jurisdiction provide incentives such as tax cuts for mobile capital. More capital increases the wages only when workers are employed and hence have higher incomes, decreasing the benefit of more capital for risk-averse workers and reducing the incentives of a jurisdiction to lower the tax and attract capital. The equilibrium capital tax thus may be too low or too high relative to the efficient level, and capital is taxed even with the head tax.

本文研究了流动资本税在劳动力市场中与匹配摩擦的作用以及这种摩擦对资本税低效率的影响。公司获得资本并创造职位空缺，工人申请公司。由于匹配摩擦，可能无法填补职位空缺，也可能不会雇用工人。企业对资本、工资和市场紧缩的投资以企业利润和工人效用共同最大化的方式确定。此外，随着资本在司法管辖区之间流动，税收后的资本回报在各个司法管辖区是均等的。一个司法管辖区的资本税增加会改变公司的资本投资、工资和该司法管辖区的市场紧缩程度。特别是，它减少了管辖范围内的就业和工资，解释为什么一个司法管辖区的政策制定者会为流动资本提供减税等激励措施。只有当工人被雇用并因此获得更高的收入时，更多的资本才会增加工资，这会降低更多资本对规避风险的工人的好处，并降低司法管辖区降低税收和吸引资本的动机。因此，相对于有效率的水平，均衡资本税可能太低或太高，即使是人头税也要对资本征税。