Discount e-commerce platform Temu has filed a lawsuit against China-founded fashion retailer Shein for using illegal practices to interfere with its business in the US.

In a lawsuit filed at the US District of Columbia court, Temu accused its rival of employing "Mafia-style intimidation" to coerce suppliers.

Shein has allegedly infringed on intellectual property (IP) rights and even falsely imprisoned Temu's merchants, among other moves to stop Temu’s growth in the US.

The locations of the merchants were not specified in the filing.

In its filing, Temu stated: “Shein has resorted to even more desperate and coercive measures, including physical detention of merchants who dare to work with Temu, personal threats, and illegal seizures of merchants’ personal devices to obtain access to the merchants’ Temu accounts and Temu’s confidential information and trade secrets. 

“Shein’s illegal scheme to disrupt Temu’s business cannot be separated from its public campaign to manufacture the false image of itself as a law-abiding corporate citizen. In numerous public statements, Shein has gone to great lengths to convince the public that Shein respects intellectual property rights and champions the rights of the merchants who supply products for resale on Shein’s websites.”

The new lawsuit comes after the two retailers had decided to drop previous lawsuits over copyright and antitrust concerns in October 2023.

In July 2023, Temu filed a lawsuit against Shein in a Boston federal court for violating US antitrust law in its dealings with clothing manufacturers.

In November, Shein confidentially filed for an initial public offering in the US, in what could be a $90bn float.

The retailer acquired Missguided, a women’s fast fashion brand, from UK-based retail company Frasers Group in October 2023.