SoftBank Group Corp. has picked banks including Nomura Holdings Inc., Goldman Sachs Group Inc. and Deutsche Bank AG as lead underwriters for the IPO of its telecom unit SoftBank Corp., Bloomberg News reported Oct 12, citing sources.

The banks, which also include Mizuho Financial Group Inc. and Sumitomo Mitsui Financial Group Inc., will help the company sell about ¥3 trillion of shares, which would make this the largest IPO ever, topping e-commerce giant Alibaba Group Holding Ltd.'s $25 billion offering in September 2014.

The Japanese mobile operator intends to commence the sale process in November and list the shares on the Tokyo Stock Exchange on Dec. 19, the sources said, adding that the timing could still change.

As of Oct. 11, US$1 was equivalent to ¥112.21.