Zekelman, 41, and his wife Stephanie were recently in the news .
Barry Zekelman and his two brothers, who took over Atlas Tube in 1984 following the death of their father, still held a 45 per cent share in the company following its sale two years ago to Carlyle Group, a U.S. private equity firm, in a deal valued at $1.5 billion.
In this latest transaction, that 45 per cent stake was worth $1.58 billion.
It's expected the sale, which still has to be approved by regulators, will close by the end of the year.
When Carlyle bought Atlas and merged it with its own John Maneely Co., Zekelman remained with Maneely and became chief executive officer.
In 1984, Atlas was a $2-million business with five employees.