SoftBank Shares Tumble Amid Tech Sector Sell-Off and AI Investment Concerns

Shares of SoftBank Group fell more than 11% following an overnight sell-off in the U.S. market on the back of wider profit taking in the tech sector.

Other Asian tech giants, including TSMC and Foxconn , also saw their share prices fall.

While the Japanese investment giant recently overtook Toyota Motor as Japan's most valuable company, there are market concerns overSoftBank's high-risk bets on AI, even as its share price has risen about 70% year-to-date on investor enthusiasm over the new technology.

SoftBank CEO Masayoshi Son told CNBC he expects the AI revolution to be 50 times larger than the dot-com revolution of the 2000s.

"Now, if you look at the history, electronics and motorization crashed in 1929, but went up for many, many years, for the next 100 years after that … so there may be some correction, but that will be the best investment opportunity to me," Son said on Monday.

The market appears "to become fixated on short-term momentum, and less interested, or unable, to map out the long-term trajectory with detailed assumptions," according to a recent investor note by Deutsche Bank analyst Peter Milliken.

Over in South Korea, Samsung and SK Hynix saw their shares decline by 1.25% and 2.75% respectively amid some profit taking, after both companies each crossed a market valuation of $1 trillion in May.

Taiwan's TSMC was down 1.65% while Foxconn fell more than 4%.

Overnight in the U.S., chip major Nvidia fell 3.62%, while Alphabet lost 0.79%. Amazon lost 2.5%.

On Wednesday, SoftBank sold a 3.25% stake of Indian eyewear maker Lenskart via its affiliate ​SVF II Lightbulb (Cayman), offloading 56.5 million ⁠shares at 508.55 Indian rupees ​each ($5.32). This sets the transaction value at around 28.73 ​billion rupees.

SoftBank's shares last traded 11.3% lower at 7,377 yen.