TOKYO (BLOOMBERG) - SoftBank Group Corp is preparing to take at least six more of its portfolio companies public this year, building on a 2020 turnaround that pushed the value of Masayoshi Son's technology conglomerate to the highest since the dot-com boom. Among the start-ups heading for initial public offerings are South Korean e-commerce pioneer Coupang Corp, Indonesian online mall operator PT Tokopedia and China's ride-hailing giant Didi Chuxing, according to people familiar with the matter, asking not to be named because the matter is private. The IPOs could give Son another round of enormous gains after successful offerings from DoorDash and KE Holdings in 2020. Mr Son started last year under a cloud after the meltdown at WeWork, then saw his shares plunge with the coronavirus pandemic and a loss of almost US$18 billion at SoftBank's Vision Fund. But the Japanese billionaire, long reluctant to cash out of investments like Alibaba Group Holding, embarked on an uncharacteristic sales blitz, raising more than US$50 billion by shedding stakes in Alibaba, T-Mobile US and its domestic wireless affiliate, SoftBank Corp. He used the cash to buy back his own shares, pushing SoftBank G...