Monex Group Inc. will merge its brokerage unit, Monex Inc., with Orix Securities Corp., an arm of Orix Corp., around next May, the two companies said Wednesday.

The deal between Monex Group, the industry's third-ranked company in terms of revenue, and seventh-ranked Orix Securities will create Japan's second-largest online brokerage in revenue, after SBI Securities Co.

Their combined revenue after integration will be ¥31.8 billion based on figures from business 2008 that ended in March. The corresponding figure for industry leader SBI is ¥47.5 billion.

Under the deal, Orix Securities will become a wholly owned subsidiary of Monex Group through a stock swap, which will come into force Jan. 17.

Meanwhile, Orix is expected to become the largest shareholder in Monex Group, with a 22.5 percent stake.