本文分析不同交易動機的內部人在不同市場關注程度公司裡進行股票買賣的獲利表現。內部人交易在未來一年可帶來正報酬。當所處的公司為市場低關注者，內部人買進後三天超額報酬為1.73%，一年後達到16.69%，顯著高於受市場高關注的公司。本文進一步依照內部人交易動機，將內部人分成機會交易者與非機會交易者。結果顯示，機會交易者在關注低公司買進股票後三天超額報酬為1.79%，一年後的超額報酬則達到17.75%。機會主義的內部人在關注低的公司中，更有空間獲取更多內部資訊，並藉由內部交易來獲取更高的報酬。

We analyze the profitability of insider trade in the low-attention and high-attention firms. Insider buy trade can make positive profits and the profits last for one year. In the low-attention firms, the insider buy trades receive 1.73% in the 3-day period and 16.69% excess return for one year. The profits are significantly higher than insider buys in the high-attention firms. We further distinguish insiders into opportunists or non-opportunists by their trading incentives. The results show that opportunistic insiders in the low-attention firms make 1.79% in the 3-day period and 17.75% excess return for one year. We provide an insight for the authority and the investors. Opportunistic traders in the low-attention firms where allow them to have more space to do the opportunistic trades obtain higher levels of inside information from the companies and return from the trades.

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