Historically, market manipulation has always been illegal... The phrase was not even defined in SEC/NASD Regulations... Because even the INTENT to manipulate prices was and is still illegal. But there is zero enforcement... Standard Algo strategies like "spoofing" and "quote stuffing"... Are flat out deliberate, premeditated market manipulation... And the SEC has done nothing. Consequently, even your average investor knows the markets are corrupt... At retail people now avoid buying individual stocks that are manipulated... And stick with "safer" ETFs. So volumes for most stocks are drying up... And because ETFs buy stocks almost indiscriminately to match indices... US markets are a joke compared to 15 years ago.