[fractionalhare]

It's true Buffett had an average annual return of 20.5% between 1965 and 2018. Soros had an average annual return of 32% over about the same time period.

Both of them have been underperforming in the last decade or so. Medallion is still radically outperforming, however.

[njarboe]

Medallion has about $6.4 billion in assets and they have kept it about that size for quite a time for a reason. It would be much harder to get those high returns when trying to invest $100 billion like Buffet tries to do.

[fractionalhare]

They're actually hard capped at $10B, up from ~$5B a decade or so ago. But you're right, they are thoroughly capacity constrained. Pretty typical for quant strategies in general.

Based on what I see from quant prop trader friends of mine in the Chicago area, if Medallion was an order of magnitude smaller they could probably juice their returns up to 150-300% pretty reliably.