From what I recall, their approach is mostly what you might call "special situations." That is, their analysis looks for significantly incorrectly priced items, and purchases/shorts them.
The Medallion Fund is kept fairly small so it can capture these items without changing their prices substantially. That is, the fund owners have to take their 40% return each year out of the fund.
>That is, the fund owners have to take their 40% return each year out of the fund.
The Medallion is for the employees money. That reminds about salary payment schema in Russian banks in 199x (don't know for today) - employees got to open very special, employees only, accounts paying extremely high, many times beyond the market, interest. The bank account interest got beneficial taxation for the employees, and the bank didn't have to pay various taxes, like social security, etc., which an employer would normally pay on salary. Of course how much an employee could put into such an account had a limit specific for a given employee, and thus the employee did have to regularly take the money out of the account.
The Medallion Fund is kept fairly small so it can capture these items without changing their prices substantially. That is, the fund owners have to take their 40% return each year out of the fund.