In late 2010, Covington & Burling dropped 3M Co. as a client. Eight days later, the law firm started work for Minnesota’s attorney general, who then filed an environmental lawsuit against none other than 3M.

Unsurprisingly, the technology company wasn’t happy with the switch, and is now suing its former firm for breach of contract and breach of fiduciary duty.

According to 3M’s complaint, Covington had advised 3M for decades, often on environmental matters. In the 1980s, the law firm helped 3M defend its food packaging products to the Food & Drug Administration (FDA), and it counseled the company again in the 1990s, when the FDA and Environmental Protection Agency investigated the tech giant’s fluorochemical business.

But in December 2010, according to the complaint, Covington partner Seth Safra sought to terminate the firm’s involvement with 3M. At the time Safra allegedly never mentioned his firm’s involvement with the state of Minnesota, despite a contract clause mandating that Covington notify 3M before taking on adverse clients.

Shortly afterwards, Minnesota Attorney General Lori Swanson hired the firm. Swanson filed suit against 3M later that month, alleging that the company’s perfluorochemicals, used to make stain-resistant products such as Scotchgard, polluted the state’s water.

3M is seeking compensatory and consequential damages, the return of all legal fees it paid to Covington over the past two decades and an injunction to keep the firm from “further jeopardizing 3M’s confidential information.”

Read more at Reuters.

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