Interpretation and Application of Double Tax Treaties - A Comparative View on the Theory and Application of the Principle of Common Interpretation and the 'new' interpretation of Art. 23 A/B OECD-MC Exemplified by the Problems of Qualifying Income and Per

对双重征税条约的不同解释和适用，特别是在收入分类和常设机构的存在方面，可能经常导致双重（非）征税。这一结果违背了缔约双方的明确意图。即使它导致双重不征税，它也会与国际公认的税收原则发生冲突，并通过避税计划扭曲竞争，这可能对福利产生负面影响。确实存在许多方法来解决这种资格冲突，其中包括共同解释原则和遵循源状态分类的方法（“新方法”）。然而，在实践中，由于担心失去主权，这些方法的复杂性和方法的不确定性，这些方法在许多国家面临保留意见。到目前为止，学者们只是从理论、案例或国家的角度来看待这些方法。本研究项目旨在从比较的角度探讨共同解释原则以及OECD-MC第23条A/B项新解释的创立原则、适用和适宜性，以防止资格冲突。这项比较研究可能会产生更多的解决办法，应当利用这些办法进一步发展现有的方法，以便提高它们的国际接受度和避免冲突的适用性。因此，将比较地说明和分析各国对遵循这些方法的义务的立场以及它们对减少资格冲突的实际意义以及各国对条约解释的看法。明确采用或拒绝这些方法的国家将成为该研究的重点。与此相一致，我们进行了比较分析，以确定贸易和资本收益收入的分类和处理差异，以及多个司法管辖区不同的常设机构概念，同时各国减少资格冲突的方法。该分析旨在探讨各国标准能够在多大程度上协调一致，并可能导致统一的条约解释。研究项目第二部分的重点是双重的，一方面是贸易收入资格，另一方面是机构常设机构的资格。这两个问题都与私募股权和风险投资基金的商业模式相关，并以其为例。

The diverging interpretation and application of double tax treaties with special regard to the classification of income and the existence of a permanent establishment may frequently lead to double (non-)taxation. This result is contrary to the explicit intent of the contracting parties. Even if it leads to double non-taxation, it causes conflicts with internationally accepted principles of taxation and enables the distortion of competition through tax shelter schemes, which may have negative effects on welfare.A number of methods do exist for solving such conflicts of qualification among others the principle of common interpretation and the approach to follow the classification of the source state ("new approach"). However, in practice these methods face reservations in many states, motivated by the fear to lose sovereignty, their complexity and methodological uncertainties. So far scholars only have looked at the methods from a theoretical, case-based or national perspective. The research project aims to explore the founding principles, the application and the suitability of the principle of common interpretation as well as of the new interpretation of Art. 23 A/B OECD-MC to prevent qualification conflicts from a comparative perspective. This comparative study may lead to an enhanced pool of solutions that should be utilized to further develop existing methods in order to improve their international acceptance and their suitability to avoid conflicts.Therefore national positions on the obligation to follow these methods and thus their practical relevance for reducing conflicts of qualification as well as national viewpoints on treaty interpretation will be illustrated and analysed comparatively. States that apply or decline those methods explicitly will form the focus of that study. Aligned with that we conduct a comparative analysis to identify differences in the categorisation and treatment of income from trade and capital gains as well as the different permanent establishment conceptions in multiple jurisdictions and simultaneously the approaches of countries to reduce conflicts of qualification. The analysis aims to explore how far national criteria are able to be harmonised and may lead to a unified treaty interpretation. The focus of the second part of the research project is twofold with income qualification of trade on the one hand and the qualification of agency permanent establishments on the other hand. Both questions are relevant to and exemplified by business models of private equity and venture capital funds.