Trading stocks on material nonpublic information constitutes insider trading. The determination of whether a material information remains nonpublic is crucial to the trader's liabilities. The regulations governing the dissemination of material information as promulgated by the Financial Supervising Commission (FSC) are both overinclusive and underinclusive. The courts are divided and inconsistent on the definition of disclosure. This article argues that FSC has to amend relevant regulations to clarify the ambiguities and to close the loopholes. The interests of both the investors and the issuers will be enhanced by such an amendment.