SoftBank Group Corp. quietly sold an additional $2.2 billion of its stake in Alibaba Group Holding Ltd. as part of the Japanese conglomerate’s fund-raising effort to pay down debt and buy back its own shares.

The deal, which includes a collar contract and call spread, is expected to be settled between May 2024 and June 2024. The details were disclosed on page 276 of SoftBank’s year-end financial filing released on June 25, but have not been previously reported. A SoftBank Group spokesman confirmed the details of the sale.

This step is the latest in an unwinding of a relationship between the two companies that spans two decades. SoftBank founder Masayoshi Son was an early backer of Jack Ma’s Alibaba and the Chinese e-commerce giant remains his most successful investment by far. In early 2000, Son invested $20 million into the then-unknown web portal connecting Chinese manufacturers with overseas buyers, a stake that is now worth more than $150 billion. Son and Ma stepped down from each other’s boards last month.

The deal brings the total of Alibaba stock sold by the Tokyo-based company this year to $13.7 billion. SoftBank in May said that it entered into several prepaid forward contracts with banks in April and May using Alibaba shares to procure a total of $11.5 billion. That includes a $1.5 billion forward contract with settlement in April 2024, a $1.5 billion floor contract with settlement in Dec. 2023 and Jan. 2024, and a $8.5 billion collar contract with settlement from Jan. to Sept. 2022.

SoftBank is in the process of offloading 4.5 trillion yen ($42 billion) of assets to bankroll stock buybacks and slash debt to reassure investors after a swoon in its shares earlier this year. In addition to Alibaba, the company is selling a stake in T-Mobile US Inc. for as much as $20 billion and stock in its domestic telecom unit.

SoftBank shares have recovered as the company has sold assets and bought back stock. The stock has climbed about 140% from their low in March and hit the highest level in two decades this month.