I study the impact of competition and taxation on the openness and the intellectual property policies of two-sided digital platforms. I model a market in which two platforms compete for users and developers. First, I find that higher competition shortens the period of exclusivity granted to developers but does not influence the degree of openness of a platform. However, the higher the degree of differentiation in the developers market, the less open the platforms are. Second, I analyze two types of taxes, ad valorem and unit taxes. Ad-valorem taxes have no effect on the length of the exclusivity period. However, they increase the degree of openness of the platform when levied on users. Unit taxes instead limit the degree of openness and increase the period of exclusivity when levied on the developers market. Lastly, I find that multi-homing reduces the exclusivity period, but does not change the qualitative effects of taxation. My findings suggest that the new digital tax proposed by the European Commission, that should come into force in 2020, may reduce openness and innovation levels in the European Union.

中文翻译：

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数字平台的知识产权和税收

我研究了竞争和税收对双边数字平台的开放性和知识产权政策的影响。我模拟了一个市场，其中两个平台争夺用户和开发者。首先，我发现更高的竞争会缩短授予开发人员的独占期，但不会影响平台的开放程度。但是，开发者市场的分化程度越高，平台的开放性就越低。其次，我分析了两种税种，从价税和单位税。从价税对独占期的长短没有影响。然而，当向用户征税时，它们增加了平台的开放程度。相反，单位税限制了开放程度，并增加了对开发商市场征收的排他期。最后，我发现多归属减少了独占期，但不会改变税收的定性影响。我的研究结果表明，欧盟委员会提议的新数字税将于 2020 年生效，可能会降低欧盟的开放和创新水平。