They're not in violation, it's high frequency trading using...

They're not in violation, it's high frequency trading using algorythms.

From what I understand is Institutional traders have setup servers right next to the exchange for lightning speed executions and as they're HFT trades they can trade with very low volume such as 1 share only.

I think it's dodgy and unethical but it's not illegal. Reporting it will fall on deaf ears and there's unlikely going to be a response at all so it's a waste of time.

Retail investors can also adjust their order size but they certainly cannot do it with the lightning speed precision of institutions employing these methods.

I've been watching this for well over a decade and nothing has changed since I first noticed it and it happens every single day on every stock they are trading.