world's largest securities firm, based in Tokyo; originated with money-changing operation of Tokushichi Nomura in 1872; expanded into stock trading in 1890s; set up financial research department 1906; first Japanese financial newsletter started 1906; entered bond trading and underwriting; incorporated with present name in 1925, emphasizing bond sales; operated investment trust business by early 1940s; company subsidiary became a member of N.Y. Stock Exchange in 1981; branch offices around the world; stock market crash of 1987 led to some retrenchment.