Wait. This is not HFT. There's a huge difference between automated and high frequency trading. What he does is only automated scalping at best (or at the fastest).

Automated trading is more on strategy, while HFT has more to do with volume and speed. With automated trading, you predict price movements. HFT involves being a liquidity provider. You don't use market technical indicators in HFT, you wait for some really huge orders.

HFT firms won't bother him. Those are dealing with an entirely different set of algorithms. He should have contacted brokers instead.