In an efficient market that has reduced systematic risk, the essential requirement of accurate pricing of financial instruments is equal access to the information, namely, disclosure. Insider trading as one of the problems related asymmetric information on financial markets prevents market transparency and beats investors' confidence. For this reason, the transmission of accurate and timely disclosed inside information to investors is intended to prevent monopolization and the use of privileged information that is unknown to everyone is prohibited in many markets around the world. In this study, the historical evaluation of insider trading with important cases beginning from the birth of stock markets is addressed. The regulations of insider trading is sorted in chronological order and referred to prosecuted cases. Moreover, EU regulations on insider trading is mentioned and the approach of new Capital Market Law No. 6362 which came into force on 2012 to insider trading is discussed. It is concluded that, the penal provisions on insider trading that can cause misappropriation must be clearly defined.peer-reviewe
