SoftBank shares jump up to 6.3% on report that Elliott Management's pushing for $15 billion in buybacks

SoftBank Group shares rose as much as 6.3% on Wednesday, after a report said that Elliott Management had rebuilt a substantial stake in the Japanese technology conglomerate and was pushing for stock repurchases.

Elliott is lobbying for $15 billion worth of share buybacks, arguing that the buybacks will boost SoftBank's share price and "act as a sign of Son's confidence in his strategy," the Financial Times reported.

SoftBank shares hit a high of 9,572 yen on Wednesday, 6.32% higher than its Tuesday closing price, according to LSEG data. The shares closed 4.6% higher at 9,420 yen on Wednesday.

Elliott's stake was valued at more than $2 billion and the U.S. fund manager had been liaising with SoftBank's senior management in the last two to three months, the report said, citing people familiar with the matter.

Founded by Masayoshi Son, SoftBank has been investing into artificial intelligence segment since declaring last year that the company was going into "offence mode" after building a huge cash pile of over $35 billion during its "defense mode."

SoftBank is betting big on U.K. chip designer Arm, which went public last year. Arm is reportedly planning to launch AI chips by 2025 to capture explosive demand.

The report further said that Elliott was targeting SoftBank for the second time, focusing on the wide gap between the combined value of the company's assets and its market valuation.

Elliott had invested $2.5 billion in SoftBank in 2020 and sought share buybacks worth $20 billion along with governance changes, Financial Times reported that year.

Elliott Management did not immediately respond to CNBC's request for comment. SoftBank Group declined to comment.

Read the full report on Financial Times.