Microsoft announces multibillion-dollar investment in OpenAI

Microsoft said on 23 January 2023 that it had agreed the third phase of its partnership with OpenAI, which it described as a multiyear, multibillion dollar investment. Microsoft gave no figure; Semafor and other outlets had reported a proposed investment of roughly $10 billion.

Why it mattered The agreement made Microsoft the principal financial backer and infrastructure supplier of the company that had released ChatGPT eight weeks earlier.

Corrections

2026-09-01 - This entry originally attributed the roughly $10 billion investment figure to “Bloomberg and other outlets.” The cited TechCrunch source attributes that figure to Semafor’s reporting on a proposed deal, and Bloomberg is not mentioned in either cited source; corrected.