A classification system for trading in securities, which replaced the alpha, beta, gamma, and delta classification used on the London Stock Exchange in January 1991. The old system had developed in a way that, contrary to the original intention, had made it a measure of corporate virility. NMS is the minimum size of the package of shares in a company traded in normal-sized market transactions; there are 12 categories. The main purpose of the system is to fix the size of transactions in which market makers are obliged to deal, and to set a basis on which the bargains should be published.
Subjects: Financial Institutions and Services.