Globally, there are more than 76 stock markets that are undergoing drastic enough growth to be considered emerging. These markets possess characteristics very distinct from those which may be characterised as mature. This paper compares interim reporting regimes in two markets with these different characteristics. The regulatory environment within the USA represent a mature market, and the Finnish regulatory environment depicts an emerging market. First, historical developments are detailed for both of these contexts. Similarities and differences in the regulation are systematically pointed out. Second, the potential consequences of some differences in regulatory schemes are discussed. Special emphasis is placed on the influences these variations have on both legislators and the producers of interim reports. This paper should offer valuable insights for the regulation of  a large number of emerging markets.