소프트웨어 도입대가 소득구분 판단기준에 관한 판례법리의 문제점 분석 및 개선방안 검토 ―2020년 이후 선고된 두 건의 판결을 중심으로―

The OECD Model Tax Convention takes a “narrow interpretation" approach, asserting that the acquisition of software copies, as opposed to acquiring a portion of software copyrights, does not constitute the introduction of know-how. In contrast, South Korea's tax authorities maintain that software acquisitions may still involve the introduction of know-how through the embodiment of such knowledge or its functional substitution. Accordingly, South Korea asserts taxation rights for the source country in such cases. The criteria for classifying software acquisition payments based on the notion that know-how may be introduced through software were established through a series of Supreme Court rulings from the late 1990s to 2000. This set of rulings formed a unique domestic taxation logic in South Korea. While this judicial precedent does not align well with the narrow interpretation adopted by the OECD Model Tax Convention, the authority to interpret domestic laws that establish taxation rights resides exclusively with South Korean courts. Therefore, as long as these judicial criteria are deemed reasonable and valid, they do not necessarily have to conform to international standards. However, a major issue with the South Korean case law is its outdated nature. The rulings were established in the context of software applications and acquisition methods that were prevalent in the 1980s and 1990s. In the digital age, software functionality and acquisition methods have diversified, become more complex, and significantly advanced, rendering the previous criteria less relevant. The software industry is a technology-intensive sector where product life cycles are short, and technological advancements occur rapidly. Today, there are hundreds of thousands of enterprise software products, making the practical application of the existing case law increasingly difficult. Specifically： 1.Due to the increased diversity of software functions and acquisition methods, circumstances previously considered indirect evidence of know-how introduction may now appear even in the case of simple product purchases. 2.The vast increase in the number of software products and acquisition scenarios makes it difficult to apply the current case law, as comprehensive consideration of all circumstances consumes excessive time and costs, hampering the timely resolution of cases. 3. Legal interpretations of key terms in the Corporate Tax Basic Regulations, such as “development," “modification," and payment methods based on “use or reproduction volume," remain ambiguous, often resulting in interpretative disputes. This paper aims to revisit the causes of inconsistencies in the current classification standards and explore potential improvements. The proposed alternatives include：adopting a broad interpretation similar to the UN approach (classifying payments as royalties, Option 1), following the narrow interpretation of the OECD (classifying payments as business income, Option 2), implementing digital taxation to address the allocation of taxing rights (Option 3), and modernizing the Supreme Court’s case law (Option 4). Option 1, which classifies all software acquisition payments as royalties, is impractical as it disregards cases where payments should be classified as business income. It also contradicts international trends and lacks feasibility. Option 3, although a more fundamental solution, does not directly resolve the income classification issue. Additionally, uncertainties remain regarding the adoption of digital taxation, as major economies like the United States remain hesitant. Option 4 proposes a transitional modernization of existing Supreme Court rulings to avoid sudden disruption to the taxation system. However, it still leaves room for subjective judgment by tax authorities, undermining legal certainty and predictability. Given the complexity and diversity of modern software applications, attempting to clearly delineate between business income and royalties in all scenarios is impractical. Therefore, whether implemented gradually through Option 4 or adopted directly, accepting the OECD’s narrow interpretation as outlined in Option 2 is the most reasonable solution. It ensures legal stability and predictability while aligning with international standards, making it the most appropriate path forward for South Korea.