共同股權對於市場競爭之影響及競爭法上可能之應對

「共同股權」係指同一相關市場水平競爭者之間存在一定比例的共同投資者，而這些投資者的交錯重疊持股恐將導致反競爭的效果。雖然早在1980年代初期，即有學者透過經濟學分析，推論出前述反競爭效果的假設。近年來，不論是經濟模式的推論，或是實證調查的研究皆陸續指出，在「共同股權」投資的情況下，將會造成市場產出（market output）減少以及價格提高的現象，並影響經營者的競爭動機。亦即，特定市場行業利潤最大化的好處會大於個別公司利潤最大化。所以共同股權股東的行為與集中投資者（即只持有該市場其中一間公司股票）不同，他們不會要求公司管理層積極競爭，甚至是以其影響力阻止競爭以提高整體行業利潤。本研究透過經濟學之角度、降低競爭動機之可能性及影響經營者決策之可能性，肯認「共同股權」對於市場之反競爭效果。雖然反對者認為前述「共同股權」的反競爭效果是建立在對於機構投資者角色的錯誤理解、研究數據未真實反映投資市場實況及欠缺因果關係來證明該影響。惟本文認為：（一）反對論點並未區分機構投資者之類型，恐因此忽略機構投資者亦可透過管理資產經理費獲利之情形；（二）MHHI指數係為計算因「共同股權」所生之市場力量，並發現傳統HHI指數無法真實反應市場現況；及（三）對實證研究立下過高門檻，應不足採。於確立「共同股權」對於市場之反競爭效果後，透過參酌相關學者文章及國外相關競爭法案例，本文針對當前市場競爭相關規範對於共同股權可能之應對提出四大思考面向：（一）將MHHI指數納入市場集中度之參考；（二）管制以整體產業獲利為計算基礎的薪酬結構；（三）以公平會為主要之監管機關；及（四）建立當然合法之「共同股權」類型。我國公平交易委員會雖然並未有相關懲處案例，但並未表示未來國內不會發生「共同股權」之爭議。本文之研究重點即在於了解「共同股權」之概念，與其在實務上所產生的問題及法律爭議，並研究我國是否有「共同股權」之情形，聚焦探討其所面臨之競爭法相關議題。希望藉此提出有關法規發展方向上的淺見，以期我國競爭法能在創新與監管中取得平衡。

關鍵字

競爭法；公平交易法；反托拉斯；共同股權；反競爭；機構投資；管制

並列摘要

This study is intended to identify and address the issue of “common ownership” in the field of competition law. The point of controversy of “common ownership” is whether firms have an incentive to reduce market competition, when large investors own shares in several firms within the same horizontal market. In the early 1980s, such anti-competitive theory had been demonstrated through economic analysis, yet prompted little public concern. Until now, the theory has gained traction by the rise of passively managed index and exchange traded funds (hereinafter the “passive investors”). In fact, an increasing number of empirical researches have focused on the issue of “common ownership”. Studies find that the investment of common ownership would lead to decreasing market outputs, raising prices and affected motive of market competitors. The core of the aforementioned phenomenon is quite clear that firms maximize shareholder value, while passive investors as shareholders tend to maximize the profits of the whole industry. This study recognizes the anti-competitive effect of “common ownership” on the basis of economic analysis and the possibilities of decreasing the motive to compete and affecting the decision of company managers. Sceptics hold that the inference is established on biased recognition of institutional investors and research statistics which failed to reveal real invest market, and that the theory is lack of causation. This study nonetheless dissent on three grounds. First, the opposition has not categorized institutional investors, thereby neglecting the fact that institutional investors might benefit from manager fee. Second, MMHI is designed for estimating the market power from “common ownership” and revealing true market status. Third, the opposition has set a threshold too high for empirical analysis. Hence, the study is convinced that the anti-competitive effect of “common ownership” is an inevitable circumstance. This study further suggests four possible response of competition law. First, taking MHHI as the reference of market concentration. Second, regulating the compensation structure based on profits of the whole industry. Third, naming Fair Trade Commission as primary supervisory authority. Forth, establishing a per se legal category of “common ownership.” Fair Trade Commission has yet sanctioned cases related to “common ownership,” and that no authority is well-informed with such issue. Given that “common ownership” might latently undermine market competition, this study focuses on the concept of “common ownership,” the following developments and legal issues. Taking its complexity into consideration, we might not be surprise that “common ownership” is the Gordian Knot in the field of competition law. Future studies, both theoretical and empirical, are essential to establish the applicable law for “common ownership”, which will strike a balance between innovation of the industry and the role of competition law to secure the foundation of a free economy.