Abstract: This paper believes that the insiders selling behavior in listing corporations has its intrinsicmechanism. The insiders selling behavior is somewhat out of increasing their liquidity, some reallocation of assets, and some obtaining excess returns using the information advantage. No matter for what purpose or what kind of motivation, starting from the rational economic mans point of view, insiders are trying to maximize their own utility and interests. The research literatures of insider trading have been too numerous to enumerate, which are covering wide scope and perspective of the numerous different, so this paper is committed to summarize the existed literatures to find intrinsic logic of the existing research. This paper studies the intrinsic mechanism from four aspects of insiders liquidity constraints, market effect of insiders trading, motivation of insiders selling behavior and legal effect of the insiders selling behavior.Furthermore, this paper extended to the Chinas special environment of capital market to make a full map of the insiders behavior, hoping to provide some theoretical contributions for future research.

Key words: reduction of insiders-holding , liquidity constraints , downward sloping of demand curve , timing selection

摘要： 本文认为上市公司的内部人减持行为具有其内在机制，上市公司内部人的减持行为有的是出于增加自身流动性的考虑，有的是对资产重新配置，有些则是利用信息优势获取超额收益，无论减持出于何种目的，源于何种动机，都是从理性经济人的角度出发最优化自身现状达到利益最大化。有关上市公司内部人交易的研究文献不胜枚举，研究的范围和角度也纷繁迥异，因此本文致力于对已有文献做一个总结归纳，找到已有研究的内在逻辑。本文从内部人持有股票的流动性限制、内部人减持的行为动机、内部人减持的外部效应以及法律监管效应这四个角度探寻了内部人减持交易存在的内在机制，同时，对中国特殊的资本市场环境下所存在的内部人减持行为的研究作了全面的梳理，希望为今后的理论研究提供一定的参考和借鉴。

关键词: 内部人减持 , 流动性限制 , 向下倾斜的需求曲线 , 时机选择