Make sure to see http://www.bloombergview.com/articles/2015-10-21/regulators-... for some reasons to doubt the charges here.
"He isn't trying to push the price with his big orders so much as get a certain type of participant to join his level whose behavior he can exploit. He's exploiting two things about market-makers. 1. They look at book imbalance to decide where to bid and offer. By balancing out the book or skewing it one way, he incites them to join and can sweep them. 2. Once they trade contracts on one side of the market, their risk management logic creates price impact or is predictable."
http://www.bloombergview.com/articles/2015-10-21/regulators-...