Jim Simons retiring from Renaissance Technologies
zerohedge.com
zerohedge.com
http://en.wikipedia.org/wiki/James_Harris_Simons for more info.
Also, he's stupidly fucking rich. Sometimes calling in rich is the right thing to do.
RenTec always made money from superior quant analytics. Like almost everyone else in quant business, they used high volume, low latency trading, so it wasn't a differentiating factor. Hence I doubt SEC would have grounds to go after them on low latency or more specifically on front running orders using low latency capabilities.