SoftBank to raise $4.1B in record retail bond sale to back Arm deal and $30 billion OpenAI bet

SoftBank Group is planning to raise 600 billion yen ($4.10 billion) by issuing bonds aimed at retail investors, according to a filing made Monday.

This marks the company’s biggest bond sale to date. The funds will go toward redeeming existing bonds and covering part of the payment for shares of chip designer Arm, which SoftBank bought back from its own Vision Fund last August.

“It is SoftBank’s largest ever bond issuance and the proceeds will be used to redeem existing bonds and to cover a portion of the outstanding payment on the acquisition of shares of chip designer Arm from its Vision Fund investment vehicle in August 2023,” Reuters reported, citing a SoftBank spokesperson.

The timing is no coincidence. In March, SoftBank announced plans to acquire Ampere Computing, a startup building Arm-based server chips, in a $6.5 billion deal. It’s clear SoftBank is betting heavily on the future of chip design and infrastructure.

Founder Masayoshi Son has never been shy about using debt to fund bold investments. Last week, SoftBank led a staggering $40 billion funding round for OpenAI—committing $30 billion of that total.

The new bonds will mature in May 2030 and offer yields between 3% and 3.6%, with the final rate to be locked in on April 18.

SoftBank currently holds around 7 trillion yen ($47.83 billion) in outstanding bonds, based on LSEG data. The company says it’s keeping an eye on its debt load, targeting a loan-to-asset ratio below 25%. As of December 2024, that figure was 12.9%.

SoftBank has been doubling down on AI lately. Alongside its OpenAI investment, it’s part of Stargate—a $500 billion private AI infrastructure push tied to former U.S. President Donald Trump. The company is also working with OpenAI on enterprise-focused AI products.

This bond sale signals SoftBank’s continued push to reposition itself as a central player in the future of AI and semiconductor tech, and it’s putting real money behind that vision.