SoftBank Group Corp. (TSE:9984) is selling about one-third of its stake in Uber Technologies, Inc. (NYSE:UBER)., in part to cover losses on its investment in Chinese ride-hailing company Didi, two people familiar with the matter told CNBC. Its planning to sell 45 million shares, which will have a 30-day lockup. Uber shares fell 5% in extended trading following the report. SoftBank has lost about $4 billion on its Didi position in total, CNBCs Deirdre Bosa reported. Its also suffered from a decline in valuation of Alibaba, the botched Ant Group IPO, and paused plans for a ByteDance listing. In addition, Softbanks Masayoshi Son has increasingly been playing in public markets with its SB Northstar unit.