[tptacek]

This is kind of a series of non-sequiturs.

Front running has always been illegal.

Arbitrage is not illegal. Latency arb certainly isn't easy.

"Dark Pools" is a book. It's also a thing, but that's obviously not what I was talking about.

There's nothing especially shady about dark pools. We'd call them "private exchanges" if the exchanges weren't themselves already private companies, I think.

[integrate-this]

Front running has not always been illegal, front-running if you have a fiduciary duty to clients has always been illegal, and many forms of front running are still legal today.

Nowhere did I imply that arbitrage is illegal and latency arbitrage is a big driver of revenue for several hedge funds, especially those which track baskets against their components.

There isn't anything shady about dark pools, except that there is little public information about the trades which take place within them, they are sparsely regulated, and you have even less insight into your counter parties than you do on open exchanges. And my response referencing dark pools was a response to your comment about execution services.

[tptacek]

Front-running has been illegal (under that name) since 1987, long before the full automation of trading. Again: front-running involves an agency relationship; by law, you're not "front running" simply by beating a part of someone's block trade to an exchange.