Obviously they cannot. It's basically subjective, and it looks like Sarao just got too greedy.
The CME does enforce rules about trade executions, that the ratio of orders placed to orders executed does not get too low (like 1/30 or something.) I'm guessing Sarao just placed a small amount of large-size orders to get around this.
The whole thing kind of surprises me as I think it is well known that there are plenty of algos that place orders with the sole intent of enticing/manipulating the market. But as I said, it's not really something you can define objectively.
EDIT: I did a bit of reading, yes, Sarao placed orders for massive size on CME. Big kahoonas for sure.
Obviously they cannot. It's basically subjective, and it looks like Sarao just got too greedy.
The CME does enforce rules about trade executions, that the ratio of orders placed to orders executed does not get too low (like 1/30 or something.) I'm guessing Sarao just placed a small amount of large-size orders to get around this.
The whole thing kind of surprises me as I think it is well known that there are plenty of algos that place orders with the sole intent of enticing/manipulating the market. But as I said, it's not really something you can define objectively.
EDIT: I did a bit of reading, yes, Sarao placed orders for massive size on CME. Big kahoonas for sure.