Some aspects of the news’ impact on stock assessment of issuers

The study discusses the impact of information on the investor behavior as well as the quotes of individual shares traded on the Moscow Exchange. The authors give a definition of an efficient market and hypothesize when the market may be inefficient in relation to the shares of Gazprom PJSC. The study of the influence of several corporate events shows that the dynamics of stocks of the selected issuer is affected by the decision of the annual general meeting of shareholders as well as the conclusion of the important contracts. At the same time, other types of corporate events like the publication of the annual reports weakly affect the dynamics of Gazprom PJSC share price. Each financial instrument has a unique set of information factors affecting its price dynamics.