SoftBank Group Corp. has issued bonds totaling US$4.2 billion (approximately IDR 68.23 trillion) in both U.S. dollars and euros on Wednesday, marking a strategic move by the tech investment giant to tap into global debt markets and accelerate its push into the field of artificial intelligence (AI).

The Japanese conglomerate’s holding company sold US$2.2 billion worth of U.S. dollar-denominated bonds categorized as 'junk bonds' across four tranches. Additionally, it issued €1.7 billion (equivalent to US$2 billion) in euro-denominated bonds in three parts, according to a source familiar with the matter who wished to remain anonymous.

The bond deal attracted investor demand exceeding US$17.3 billion.

As part of SoftBank’s massive AI investment ambitions, its billionaire founder Masayoshi Son has pledged up to US$500 billion for a major initiative known as “Stargate.” Earlier this year, he also announced a planned investment of US$30 billion in OpenAI Inc.

Nonetheless, highlighting the regulatory hurdles Son faces in his rapid global expansion, the U.S. Federal Trade Commission (FTC) has reportedly launched an in-depth antitrust investigation into SoftBank’s US$6.5 billion acquisition of semiconductor designer Ampere Computing, according to Bloomberg this week.

At SoftBank’s annual shareholders meeting in June, Son vowed to transform the company into a leading platform for artificial intelligence within the next decade.

SoftBank has already raised more than ¥600 billion (approximately US$4.2 billion) through yen-denominated bond issuances this year—marking the largest issuance by a single corporate borrower in Japan’s debt market, according to data compiled by Bloomberg.

“Japanese investor exposure to SoftBank has grown significantly,” said Taketoshi Tsuchiya, Chief Executive Officer of Tsuchiya Asset Management Co. “In such market conditions, tapping into foreign demand makes perfect sense.”

U.S. dollar bond issuance has gained momentum this year due to improving investor sentiment and declining funding costs.

On Monday, SoftBank Corp.—the mobile network subsidiary listed under SoftBank Group—also priced US$1 billion in dollar-denominated bonds, marking its first high-grade bond sale in the U.S. market.