Credit rating agencies assigned the company investment-grade ratings last week, signaling confidence in SpaceX's financial  stability  as it moves forward with its costly AI plans.

That definitely perks up my ears for a company that is not generating a profit[0]. Does investment-grade rating mean something different than I assume?

[0] recent datacenter rentals may have pushed it into the green

Presumably the idea here is that by having a significantly higher value (I want to use the word "inflated" but thats perhaps over pejorative in context) they can access better interest rate debt from the bond market because they are now considered near-gilt, "too big to fail" within the lifetime of the bond.

Which in turn is a virtuous circle because for the existing debt size, they reduced cost so reduced the risk of debt overhang by the difference in repayment cost.

It's another example of the advantages of size. It will create a secondary market in the paper.

I'm an AI skeptic, and I don't like Musk. Naturally I think this is a bad bet, I think the inflated value is going to return to normal as the AI bet fails to pay off. The bond holders will in turn discount, and the other virtuous circle of market sentiment will emerge: yields on bonds tell a story.