(Yicai) Sept. 18 -- Shares of Tesla’s Chinese suppliers such as Tuopu Group and Sanhua Intelligent Controls retreated from intraday highs after the firms said they had no knowledge of factory inspections in China tied to the US firm’s Optimus humanoid robot, following a report that a Tesla team arrived in Ningbo this week to assess suppliers ahead of mass production.

After climbing by almost 7 percent in Shanghai this morning, Tuopu [SHA: 601689] closed up 2.8 percent at CNY45 (USD6.71) per share. Sanhua [SHE: 002050] retreated from an earlier gain of 4.3 percent to finish 1.9 percent higher at CNY35.31 (USD5.27).

Tuopu has not received any notification about a facility inspection by Tesla, a representative for the Ningbo-based company told Yicai. The pair have collaborated on linear and rotary actuators as well as dexterous hand actuators, the person said, adding that the production base for these components is ready.

A Sanhua representative said the Shaoxing-based manufacturer was not aware of Tesla's new round of facility inspections, but did confirm that it is working with a major client on developing robot joint actuators.

According to a report published yesterday by 21st Century Business Herald, a Tesla inspection team arrived in Ningbo on Sept. 16 to check the facilities of potential suppliers as the Austin-based company prepares to begin mass production of its Optimus robot. Tesla has already issued orders to various suppliers, the report said.

“Tesla's R&D personnel are typically present at the factory in Ningbo, which handles both auto and robotics businesses,” the Tuopu representative pointed out.

Previous reports had said that Tesla launched a round of robotics facility inspections in China last September, involving some of its already established automotive supply chain partners, such as Tuopu, Sanhua, Xinquan Automotive Trim, and Joyson Electronics.

A Joyson representative declined to comment on the matter today, citing client confidentiality. After gaining by as much as 5.6 percent in morning trading, Joyson’s stock price [SHA: 600699] ended 1.4 percent higher at CNY20.14 (USD3).

Editor: Tom Litting