You don't have the ability to back out after your quote is accepted. But you have the ability to back out on a majority of your quotes, if you submit so many t

You don't have the ability to back out after your quote is accepted. But you have the ability to back out on a majority of your quotes, if you submit so many that they couldn't possibly be fulfilled in the time before you cancel them. Despite the fact that they are cancelled, they still have their effect. http://www.zerohedge.com/article/how-hft-quote-stuffing-caused-market-crash-may-6-and-threatens-destroy-entire-market-any-mom http://www.zerohedge.com/article/how-hft-quote-stuffing-caus... Also, if you are a broker, the exchange imposes similar requirements on fill rates Then why aren't these algorithms being banned?