Richmond and Baltimore are suing dozens of chemical companies and individuals who, they allege, conspired for years to drive up the price of aluminum sulfate, which is commonly used to treat municipal water.
The cities filed antitrust lawsuits in federal courts Monday over what they say was a price-fixing and bid-rigging scheme that went on from 1997 until at least 2011. Federal investigators have been looking into collusion in the industry for years, and Richmond and Baltimore are joining other cities across the country in suing.
Some defendants in the suits have pleaded guilty. Others have been indicted.
The complaints allege the companies intentionally submitted losing bids, withdrew winning bids and unlawfully discussed their quotes.
The complaints say the defendants' actions caused municipalities across the U.S. to overpay by millions.