David Hirschhorn announced yesterday that he would retire June 30 as chairman of American Trading and Production Corp.
Mr. Hirschhorn, 74, will continue as a director of the Baltimore-based oil conglomerate.
He had been president and chief executive officer, and became chairman when Morton K. Blaustein died late last year.
"I've reached the time of life when I should retire," Mr. Hirschhorn said yesterday.
"Other people will carry on" the business of American Trading, which also has interests in office products, real estate developments and electronics companies, Mr. Hirschhorn said.
The company said yesterday that Louis B. Thalheimer had been elected chairman. He became president and chief executive after Mr. Blaustein's death.
Hans Fristedt, who joined the company in November, was elected president and chief operating officer.
The company also said Sanford V. Schmidt had assumed the new position of vice president and chief administrative officer.