SoftBank Group (TYO:9984) will invest a further $30 billion in OpenAI Group PBC through SoftBank Vision Fund 2, lifting its cumulative commitment to $64.6 billion and giving it an ownership stake of about 13%, according to a Monday filing on the Tokyo Stock Exchange.

The investment will be made in three $10 billion tranches scheduled for April, July and October. The securities are preferred shares that will automatically convert into common stock upon an initial public offering or related listing.

SoftBank has invested $34.6 billion in OpenAI since September 2024. The latest funding values the U.S.-based company at a pre-money valuation of $730 billion.

The investment will initially be financed through bridge loans and other arrangements with major financial institutions, with longer-term funding to be arranged later.