Recently, cross-border e-commerce platform Temu filed a complaint with the UK Competition Appeal Tribunal (CAT), accusing global fast-fashion giant SHEIN of abusing its dominant market position by forcing suppliers to sign exclusive agreements to squeeze out competitors, and is seeking damages.

On July 14, 2026, during a case management hearing, Temu’s attorneys argued that SHEIN is an “indispensable” platform for many suppliers and therefore has the ability to force them to accept agreements that restrict competition; SHEIN’s attorneys countered, demanding that Temu fully substantiate its claims using statistical methods such as econometrics. The two sides also have significant disagreements regarding the definition of the relevant geographic market, with Temu arguing for a global market analysis, while SHEIN focuses on the Chinese market where its core suppliers are located.

This case stems from a counterclaim filed by Temu in response to a copyright infringement lawsuit brought by SHEIN. In August 2023, SHEIN sued Temu and its sellers in the United Kingdom for large-scale misappropriation of product images. In February 2024, the High Court of Justice in the United Kingdom ruled in favor of Temu’s motion to dismiss the infringement claims and allowed Temu to pursue its own claims. This ruling directly prompted Temu to file a counterclaim based on antitrust grounds.

In addition to the UK, litigation between the two parties in the United States remains deadlocked. In April 2026, a federal judge in Washington, D.C., consolidated the two parallel lawsuits for joint consideration. SHEIN is accused of suppressing Temu by issuing thousands of improper takedown notices and coercing suppliers, while Temu is charged with aiding in the sale of counterfeit goods, misappropriating trade secrets, and copying product images.

Case Background

In December 2022, SHEIN first sued Temu in the U.S. District Court for the Northern District of Illinois;

On July 14, 2023, Temu filed a lawsuit in the U.S. District Court for the District of Massachusetts, alleging that SHEIN violated U.S. antitrust laws;

In August 2023, SHEIN filed an intellectual property lawsuit against Temu in the High Court of Justice in the United Kingdom, alleging widespread copyright infringement by Temu and its sellers, and seeking an interim injunction from the court;

In September 2023, the British court issued an interim injunction against Temu;

In December 2023, Temu filed another lawsuit in the U.S. District Court for the District of Columbia, alleging that SHEIN forced fashion suppliers to sign exclusive agreements and threatened Temu merchants;

In February 2024, the High Court of England and Wales issued a ruling finding that the “exclusive operating agreements” signed by merchants upon joining the platform were insufficient to prove that SHEIN held copyright to the images. That same month, Temu filed a counterclaim under competition law with the Competition Appeal Tribunal (CAT), alleging that SHEIN had violated the UK Competition Act 1998;

In November 2025, the CAT issued an order requiring SHEIN to disclose a list of approximately 450 core suppliers who had signed “Supplier Certificates.” SHEIN immediately appealed the decision to the UK Court of Appeal;

On March 5, 2026, the UK Court of Appeal dismissed SHEIN’s appeal;

On July 14, 2026, a case management hearing was held at the CAT in the case of Temu v. SHEIN regarding the alleged abuse of a dominant market position.