3M’s legal battle to keep price gougers from profiting on sales of its N95 face masks during the coronavirus pandemic grew on new fronts.

The Star Tribune reports that on Monday, 3M targeted a third-party seller on Amazon.com for using its trademark to sell $350,000 worth of masks at up to 20 times list prices.

KM Brothers Inc., a California company trading under several different business names, “claimed to be reselling authentic N95 respirators, while actually selling damaged and fake goods at highly inflated prices,” 3M said.

After customer complaints, Amazon pulled the KM Brothers ads from its online shopping forum.

3M’s federal court lawsuit against Mao Yu, the owner and operator of KM Brothers, explains a strategy that uses multiple business names to carry on selling if a single business gets taken down.

3M said that on Feb. 20, various business under KM Brothers control began selling “what were purported to be 3M-branded N95 respirators across three connected accounts on Amazon.com.”

The company also “maintained at least 45 different Amazon Standard Identification Numbers.”

The new lawsuits offer a glimpse into the depth and breadth of attempts to profit from a national shortage of N95 masks, said to be among the most effective in blocking airborne COVID-19 molecules.

The new legal actions bring to 14 the number of suits 3M has filed since January to try to control price gouging for its product by what the company calls “pandemic profiteers.”

3M said it “has won five temporary restraining orders and three preliminary injunction orders from courts across the country that put a stop to other defendants’ unlawful and unethical profiteering from the pandemic.”

It has shut down more than 3,000 websites and 4,000 social media posts that try to expropriate the 3M brand for profit, the company explained.

3M asks the court to shut down KM Brothers’ mask-selling operations and to force the company to repay any profits derived from by claiming the resale of 3M masks when it was instead “selling counterfeit, damaged, deficient, or otherwise altered masks.”

The seller charged Amazon customers up to $23.21 for a single mask that normally listed for prices ranging from 60 cents to $3.40 each. Customer complaints tipped off Amazon.