I am doing a report about famous quant companies such as Renaissance Technologies. Where can I find information such as ranking of these companies and their fund's rate of return.
Most RIAs have to file a Form ADV, through which some information is publicly available via SEC's website.
Further, large RIAs are sometimes involved in high profile civil lawsuits through which information, e.g. revealed by current or former employees in the discovery process, becomes accessible in the form of public court filings. This would be available through the PACER system.