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，特别是关于收入分类和常设机构的存在，可能经常导致双重(非)征税。这一结果与缔约方的明确意图背道而驰。即使它导致双重免税，也会导致与国际公认的征税原则相冲突，并通过避税计划扭曲竞争，这可能对福利产生负面影响。确实有一些方法可以解决这种资格冲突，其中包括共同解释原则和遵循来源国分类的办法(“新办法”)。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上的不确定性，这些方法在许多国家面临保留意见。到目前为止，学者们只从理论、案例或国家的角度来看待这些方法。该研究项目旨在从比较的角度探讨共同解释原则的创立原则、适用情况和适用情况，以及第23条A/B、OECD-MC的新解释，以防止资格冲突。这项比较研究可能导致更多的解决办法，这些办法应被用来进一步发展现有的方法，以提高它们在国际上的接受度和适用性，以避免冲突。因此，将比较说明和分析各国关于遵循这些方法的义务的立场，以及它们对减少限定冲突的实际意义以及各国关于条约解释的观点。明确采用或拒绝采用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，以确定在贸易和资本收益的分类和处理方面的差异，以及多个法域不同的常设机构概念，同时确定各国减少资格冲突的方法。这项分析旨在探索各国标准在多大程度上能够协调一致，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，一方面是贸易的收入资格，另一方面是机构常设机构的资格。这两个问题都与私人股本和风险投资基金的商业模式相关，并得到了它们的例证。

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.