An astute investor can check insider buying or selling by company directors or their key insiders. Such share transactions-activity must be filed to the SEC regulators, as in Thailand they must and do. While insiders may have many reasons to sell; there is only one reason why they would buy. An insider may have to pay for a wedding, a new car, an education for his/her children, a trip, a new house, etc...but when an insider buys it just about always means they think their stock is presently undervalued. Of course, they can be too early or late or outright wrong, but its a solid additional investor tool to confirm other supporting fundamental analysis -when considering investing in a listed companies's stock. We here follow such activity consistently.