Comparative Study of Securities issuer's affirmative duty to disclose information in Iranian and American Law

In accordance with Articles 40 and 45 of the Securities Market Act securities issuers are obliged to disclose information on primary and secondary market. These requirements include two aspects: the negative and the affirmative aspect. The negative aspect of These requirements include the issuer's duty to not disclosing false or misleading information, no doubt. But the affirmative aspect of this duty, in general, that means the publisher obligation to disclose all information that may influence investment decisions, is debatable. Especially in American judgmental procedure, issuers’ affirmative obligation to disclose all important information is not accepted. In this article, we will examine comparatively, in Iranian contract law and securities law, If there is a general duty for issuers to disclose all material information. If we accept this duty, what criteria should be used for distinction of information that must be disclosed and when the issuer must disclose these information? These issues will be discussed. In short, it seems to for the necessities of the Iranian capital market, and also according to the Securities Market Act and its guidelines for disclosure of information on primary and secondary markets the issuers are obliged to disclose the information, and this duty is limited to information that significantly affect investment decisions and stock prices.