SoftBank Group said it bought American semiconductor design company Ampere Computing Holdings for $6.5 billion, completing a deal the Japanese conglomerate first announced in March.

Santa Clara, California-based Ampere, which was founded in 2017 by former Intel veteran Renée J. James, has become a wholly owned subsidiary of the Japanese company, according to an announcement on Wednesday. Shares of SoftBank closed 5.1% higher, after rising as much as 8% during Tokyo trading hours. The company is still reviewing the transaction’s impact on its financial results.

The group’s founder Masayoshi Son , who is Japan’s richest person with a net worth of $51.8 billion, has viewed the Ampere deal as an integral part of his vision to drive innovation in AI and computing. Ampere is expected to have a “strategic alignment” with other SoftBank group companies and investees, according to the March announcement. Ampere uses technologies developed by Arm Holdings, a British semiconductor design firm majority owned by SoftBank. “Ampere’s expertise in developing and taping out ARM-based chips can be integrated, complementing design strengths of Arm Holdings,” SoftBank said in its March statement.

Son has been revamping the group’s AI-related bets. In November, SoftBank announced that it had offloaded the company’s entire stake in chipmaker Nvidia for $5.8 billion. The proceeds from the divestment comes handy as the Japanese conglomerate seeks additional financing for its massive investment in ChatGPT owner OpenAI. SoftBank has committed to invest $30 billion in the firm, and has announced a web of deals that include investing in OpenAI’s Stargate AI mega infrastructure project in the U.S.

But Son’s ambition hasn’t been entirely smooth sailing, especially as the ChatGPT creator now faces steep competition from the likes of Google. The latter’s new Gemini 3 AI model is deemed to be more advanced than OpenAI’s platform, with Salesforce’s billionaire cofounder Marc Benioff saying he won’t go back to ChatGPT after using Gemini 3, which has an “insane” leap in reasoning capabilities. Concerns around OpenAI’s future have hurt SoftBank, causing its shares to slump nearly 11% on Tuesday before recovering today.