Rumor has it, they had been trying to get more, and failing. No audited records of that kind of thing, of course, so could be untrue. But Altman and others had publicly said that they were attempting to get Microsoft to invest more, and he was courting sovereign wealth funds for an AI (though non-OpenAI) chip related venture, and ChatGPT had a one-day partial outage due to "capacity" constraints, which is odd if your biggest backer is a cloud company. It all sounds like they are running short on money, long before they get to profitability. Which would have been fine up until about a year ago, because someone with Altman's profile could easily get new funding for a buzz-heavy project like ChatGPT. But times are different, now...