「競爭」是一種狀態,它是一種動態的過程。從公平交易法的觀點出發,「相關市場」係指事業提供商品或服務並從事競爭的範圍,包含相關產品市場及相關地理市場兩個構面。數位匯流對於現有「相關市場」定義產生巨大的衝擊。隨著科技快速發展,將使商品或服務的相互替性能力提高,過去說文解字的「相關市場」,其邊界已日益模糊。 縱使「相關市場」之界定,雖有其個案認定之色彩,但基於適用法律之明確並且為求法之可預見性,管見建議在傳統的相關產品界定之外,尚應充分考慮「時間因子」以期符合電信事業之特性。此外,關於相關地理市場之界定,管見以為傳統的「運輸測試法」於適用電信服務恐有其疑義,是以管見以為嘗試從「空間替代性」進一步討論之。
Competition is a status, further, a dynamic process. Based on the theme of Fair Competition Law, "Relevant Market” was defined as “the business competitive market” where enterprises render or sell no matter products or services and could be understood from two dimensions, which are relevant product market and relevant geographical market. Inevitably, digital convergence creates huge impact on current definition of relevant market. Rapid technological evolution has increased the mutual substitution between physical products and intangible services, thus the literal definition and the boundaries of two are getting vaguer and vaguer. Due to the certainty and predictability of legal frame, the author suggests that elements of timescale need to be considered when the relevant product (even should be defined case-by-case) is referring to the telecommunication industries. The author also recommends that the Test of Spatial Substitutability to demonstrate the bound of geographical market rather than the traditional Shipment Test to telecommunication practices is more capable to avoid problematic applications.