Arkansas Republican Senator Tom Cotton has urged US authorities to open a formal investigation into online retailers Shein and Temu, accusing the platforms of extensive intellectual property (IP) violations and counterfeiting. 

In a letter to Attorney General Pam Bondi seen by Reuters, Cotton urged the Department of Justice and the Department of Homeland Security to examine the activities of the two companies, which ship the bulk of their products from China. 

He argued that recent changes to US trade rules warranted closer scrutiny. 

Cotton referred to the recent termination of a customs exemption that had allowed imports worth less than $800 to enter the US without duties.  

According to the letter, this policy shift has “forced Shein and Temu to change their business model.” 

Cotton told Reuters: “These companies now stock massive inventories in US warehouses and distribution centres. Their goods are no longer slipping through ports. They are sitting on American soil under US jurisdiction.” 

The call for a probe adds to ongoing regulatory and political pressure on both marketplaces, which have built large user bases by offering low-priced clothing, accessories and other consumer goods.  

Shein is privately owned, while Temu is operated by PDD Holdings.  

Neither company provided immediate comment on Cotton’s letter. 

Regulators in other jurisdictions have also heightened their focus on the platforms.  

In July 2025, the European Commission said that Temu was infringing European Union rules by not doing enough to curb the sale of counterfeit items.  

Temu responded at the time that it would cooperate fully with the process. 

Shein has previously stated that its suppliers are required to confirm their goods do not breach IP rights and that it takes rapid action against those found to be in violation. 

In a separate development, Texas Attorney General Ken Paxton has launched an inquiry into whether Shein has broken state laws concerning alleged unethical labour practices and the sale of unsafe products. 

French authorities have also moved against the fast-fashion group.  

In November, the French government petitioned a Paris court to order a three-month nationwide suspension of Shein’s operations, after officials reported finding childlike sex dolls and banned weapons listed on its platform.