I would think they keep the fund private, and return profits annually, to keep the size of the fund limited. The strategies they employ probably cannot work as

I would think they keep the fund private, and return profits annually, to keep the size of the fund limited. The strategies they employ probably cannot work as well at larger scale. Here's a rare interview with Jim Simons: http://ritholtz.com/2016/07/jim-simons-mathematician-cracked-wall-street-2/ http://ritholtz.com/2016/07/jim-simons-mathematician-cracked...