INSURANCE

Equitable Officially Goes Public: Equitable Life Assurance Society of the United States officially became a public company when its new parent, Equitable Cos., completed a $450-million common stock offering on the New York Stock Exchange. Up to now, the huge insurer has operated as a mutual company owned by its policyholders. Equitable’s 50 million shares of common stock, offered at $9 a share July 15, lost 25 cents Wednesday to trade at $9.25 in NYSE trading. The stock began trading July 16.