China has placed the leading research company TechInsights on its Unreliable Entity list, effectively banning the Canadian teardown specialist, known for uncovering the inner workings of Huawei Technologies Co.’s AI chips, from operating in the country.

According to a statement from the Ministry of Commerce on Thursday, TechInsights, along with several other firms including certain drone manufacturers, will be prohibited from conducting business with Chinese organizations or individuals.

Since 2023, the Canadian firm has been instrumental in revealing some of Huawei’s most closely held technological secrets, highlighting the company’s continued dependence on foreign chips despite years of attempts to substitute American components, according to Bloomberg.

Renowned for its meticulous teardowns that map out the internal parts of electronic products, TechInsights was the first to identify several previously undisclosed suppliers and components in Chinese hardware.

In a 2023 Bloomberg investigation conducted with TechInsights, it was revealed that Huawei had developed a domestically made smartphone processor capable of competing with offerings from Qualcomm Inc. and Apple Inc.

TechInsights also verified that Huawei devices contained restricted chips from Taiwan Semiconductor Manufacturing Co., revealing how the Chinese company relied on intermediaries to bypass US sanctions and obtain critical components.

Just last week, the firm further identified key parts from TSMC, Samsung Electronics Co., and SK Hynix Inc. within Huawei’s most advanced AI semiconductors.

“Foreign entities such as Dedrone by Axon and TechInsights and their affiliates have defied China’s strong objections to engage in activities such as so-called military-technical cooperation with Taiwan, made malicious remarks concerning China and assisted foreign governments in suppressing Chinese companies,” the ministry said in a separate statement.

TechInsights did not immediately respond to requests for comment.