New York CNN  —  Federal prosecutors in California on Friday charged prominent investor Andrew Left with multiple counts of securities fraud involving “a long-running market manipulation scheme” yielding at least $16 million in profit. The Department of Justice said Left, the founder of Citron Research, “exploited his ability to move stock prices” using social media to amplify and exaggerate market reactions. Left’s investing style is known as short-selling, a high-risk strategy that allows investors to bet against stocks they see as overvalued. Short-sellers, including Left, often present themselves as researchers sniffing out misleading or fraudulent businesses through independently published reports on their targets. Citron had a notable win in 2015, when it bet against Canadian pharmaceutical giant Valeant, accusing it of creating fraudulent invoices and comparing it to Enron. The company was later investigated by the Securities and Exchange Commission, leading its stock to plummet 90% from its peak. Left, 54, was charged with one count of engaging in a securities fraud scheme, 17 counts of securities fraud, and one count of making false statements to federal investigators. Each securities fraud count carries a maximum prison sentence of 20 years. Separately, the SEC on Friday accused Left and his firm of running a $20 million scheme to defraud his social media followers by publishing false and misleading reports. Citron did not immediately respond to CNN’s request for comment. On its website, the firm says its goal “has always been to provide truthful information in an entertaining format to the investing public.” “It is obvious that the vast preponderance of companies (but not all – so who’s perfect?) covered in the archived reports performed poorly as investments,” Citron says on its website. “Readers are welcome to compile their own track records and draw their own conclusions.”