I've read a bunch on KCG today and no mention of who wrote the software. I am wondering if they possibly have an in house group that develops these algorithms. Seems many use their execution software. It will come out soon enough.
I can tell you one thing. I don't short too many stocks, but I am taking pleasure in shorting KCG. I look forward to their demise and will love to kick them while they are down. NITE are the biggest criminal scumbags in the whole business. They have naked shorted every penny stock around. I love shorting KCG it feels so right !