[qeternity]

Impossible to really say without splitting RenTech into its different funds (you're probably referring to Medallion) and knowing what the underlying strats are. But at a high level the difference between MMs and quant funds are AUM which means different time horizons. An MM might have a time horizon measured in mics to seconds, and might be focused on micro market analysis like the balance of order book over the next 1,000 microseconds. RenTech (likely) can't deploy all of their capital in these types of strategies so they focus on strats with better liquidity and almost certainly longer time horizons (minutes to hours and days, possibly weeks for more CTA style strats). And at the opposite end of the spectrum, Berkshire can deploy tens of billions in a single trade, but that means an investment horizon of years to decades.