短线交易制度是维护证券市场秩序的重要制度，该制度具有客观责任、自动适用的特点，主体构成要件是短线交易行为认定中的重点。现行《证券法》将法定内部人的配偶、父母、子女及利用他人账户持股的情形纳入监管范围，但实践中如何认定短线交易主体标准仍不统一，有必要对短线交易主体认定标准予以细化。 本文结合域外国家的立法经验、我国短线交易执法实践以及法经济学理论，对短线交易主体要件及其认定标准进行研究。对短线交易的主体认定应当划分为三个层次，分别为短线交易制度直接适用的主体范围，短线交易制度推定适用的主体范围以及利用他人账户持股交易的情形。第一个层次为直接适用的主体范围，凡属于该主体范围内，短线交易制度即自动适用，无豁免性规定，包括持股达到一定比例的大股东及上市公司董监高，其中大股东的持股比例门槛不应由百分之五提升至百分之十。我国股权集中程度高，且主要集中于单一大股东，提高短线交易制度中大股东的持股比例要求会将大量股东排除在监管范围之外，将该制度适用范围限制在第一大股东及董监高范围内。第二个层次为推定适用的主体范围，此类主体不属于法定内部人，但因其与内部人的特殊关系而常被内部人借用账户以逃避监管。短线交易制度推定适用的主体应当包括法定内部人的配偶、父母与子女，但应允许内部人提出证据反证。法定内部人的关联方及法人股东的董监高不应被纳入短线交易推定适用的主体范围。第三个层次探索如何认定“利用他人账户”，以及该情形下如何适用《证券法》第四十四条与第五十八条。应以证券账户决策权为判断依据，结合身份关系、资金来源、利益归属等方面对“利用他人账户”作出补充规定，提升短线交易制度的可操作性。在“利用他人账户”进行短线交易时，应同时适用短线交易制度与“借用他人证券账户”的禁止性规定，对“利用他人账户”进行短线交易行为予以处罚。此外，短线交易主体身份的动态认定探讨法定内部人在短线交易行为两端不同时具备身份要件时是否应当被纳入监管范围。应根据不同主体对内部信息的了解能力，对董监高与持股百分之五以上的股东进行区分，采取“折中说”的标准。对于获取公司内部信息能力较强的董监高，采取在交易一端具备法定身份即符合主体要件的标准；对于获取公司内部信息能力较弱的股东，采取在交易两端均具备法定身份才符合主体要件的标准。

The short-swing trading system is an important system for maintaining the order of the securities market. The system features objective responsibility and automatic application. Therefore, the subject constituent element is a key point in the identification of the short-swing trading. The current Securities Law includes the shareholding held by legal insiders' spouse, parents, and children and making use of others’ account into the supervision scope, but the standards for identifying entities engaging in short-term trading are not unified in practice, so it is necessary to detail the standards for identifying entities engaging in short-term trading.This paper studies the subject constituent element of short-term trading and the identification standards for short-term trading on the basis of the legislative experience of other countries, the law enforcement practice and the economics of law. The identification of the subject of the short-swing trading system shall be divided into three levels, namely the scope of the subject to which the short-swing trading system directly applies, the scope of the subject to which the short-swing trading system is presumed to apply, and the circumstances of trading shares by holding others’ accounts.The first level is the scope of subjects that are directly applicable to the system. The short-swing trading system shall apply automatically to any subject that is within the scope of such subject without any exemption, including major shareholders holding a certain percentage of shares and directors, supervisors and senior management of listed companies. The shareholding percentage of a major shareholder shall not be raised from 5% to 10%. Given the high degree of concentration of equity in China, which is mainly concentrated in single major shareholders, raising the shareholding percentage of a major shareholder under the short-term trading system may exclude a large number of shareholders from the regulatory scope, thereby substantially limiting the system to the largest shareholder, directors, supervisors and senior management personnel.The second level is the scope of subjects applicable to presumption, which is not the insiders, but the insiders often use their accounts to escape the supervision because of their special relationship with insiders. The subjects to which the short-swing trading system is presumed to be applicable shall include the spouses, parents and children of insiders, but insiders shall be allowed to provide evidence to prove the contrary. The related parties of legal insiders and directors, supervisors and senior executives of corporate shareholders shall not be included in the scope of subjects to which the short-swing trading system is presumed to be applicable.The third level is to explore how to identify "using other’s accounts" and how to apply Articles 44 and 58 of the Securities Law under such circumstance. Supplementary provisions on "using others' accounts" shall be made on the basis of decision-making rights for securities accounts and in light of the identity relationship, source of funds, attribution of interests, etc., so as to enhance the operability of the short-swing trading system of the Securities Law. Both the short-swing trading system and the prohibitive provisions on "borrowing others' securities account" shall be applied to impose punishments on the behavior of using others’ accounts for short-swing trading.In addition, the dynamic identification of short-term trading subjects discusses whether the insiders should be included in the scope of regulation when they do not meet the identity requirement at the two ends of short-term trading. Directors, supervisors and senior management personnel shall be differentiated from shareholders holding more than 5% of the equity on the basis of different entities' ability to acquire internal information. A "compromise" standard shall be applied. For directors, supervisors or senior management personnel who have strong ability to access the company's internal information, having an insider identity at one end of the transaction satisfies the subject standards; for shareholder with weak ability to access the company's internal information, having an insider identity at both ends of the transaction satisfies the subject standards.