Four men in Southern California have been charged in a scheme that made $70 million in illegal sales of HIV meds, reports CBS San Francisco.

According to the indictment, the men bought HIV meds on the black market and created false documents claiming they had been obtained from legitimate sources. The men then conspired to sell these prescription drugs to retail pharmacies and wholesalers across the United States.

They sold the meds through a company called Mainspring Distribution and, the indictment alleges, laundered proceeds from the sales. During the course of the scam, CBS reports, Mainspring made more than $70 million from these drug sales.

What’s more, Mainspring’s customers had no idea the prescription meds had been acquired illegally.

The four men indicted in the case are Edvin Ovasapyan, Hakob Kojoyan, Lorik Papyan and Stephen Silverman. CBS reports that they are charged with several counts of conspiracy, including conspiracy to commit wire fraud and money laundering and conspiracy to engage in the unlawful wholesale distribution of drugs. Each of the charges comes with its own possible sentence. For example, for money laundering, the men face a maximum of 20 years in prison, a $500,000 fine (or twice the value of the property involved) and compensation for loss.