Nuclear Corporation of America, Inc. was first listed on the American Stock Exchange in 1955 and subsequently reincorporated in Delaware, adopting the name Nuclear Corporation of America in 1958.  In 1972, Nuclear Corporation of America reclassified its stock, changed its name to Nucor Corporation, and listed its stock on the New York Stock Exchange. The stock reclassification involved a one-for-four reverse stock split. Since the stock price was low at the time and the NYSE required a higher price to be listed, shareholders received one share of Nucor stock for every four shares they held in Nuclear Corporation.  Nucor kept the NUE ticker symbol under which Nuclear Corporation had traded for many years.

The name change to Nucor in 1972 was proposed by Sam Siegel, who was Vice President of Finance, Treasurer and Secretary at the time.  Nucor had been a registered trademark of the Nuclear Instruments division since 1959 and already appeared on stock certificates. The management team believed that the new name more accurately reflected the nature of the company since the nuclear business had fallen to less than 5% of sales.

In July 1972, Ken Iverson, Sam Siegel, outside counsel Ernest DeLaney and others visited the floor of the NYSE to witness the initial trading of NUE shares on the Big Board. Over the years, Nucor has been invited to ring the opening and closing bell of the NYSE, celebrating such milestones as listing anniversaries, dividend records and retirements.