Shares of Chinese humanoid robot maker Ubtech Robotics Corp Ltd (9880.HK) tumbled 31.6% Monday after its CEO dissolved concert party agreements with some of its shareholders.

Ubtech previously announced that Zhou Jian, Ubtech's chairman of the board, executive director and chief executive officer, entered into a termination agreement with each of the company's five shareholders to terminate the concert party agreement respectively, effective Dec. 29, 2024.

This change is expected to streamline the decision-making process at board meetings and shareholders' meetings.

Upon termination of the agreements, Zhou and the other shareholders will each have less than 30% of the voting rights and will no longer be controlling shareholders of the company.

Ubtech's board of directors said the change will not have a material adverse effect on the company's operations and will update relevant information in due course.

Meanwhile, Ubtech disclosed Sunday evening that as of Dec. 29, 2024, Zhou is the legal and beneficial owner of 70,400,000 Hong Kong-listed shares in the company.

Zhou promised that within 12 months from Dec. 29, 2024, he will not reduce his holdings of the Hong Kong-listed shares in any way, according to an announcement.

In response to the share price plunge, Ubtech said Monday, "The company respects that its shareholders have different plans for the disposal of the Pre-IPO shares on the basis of long-term optimism for the company."

"The company's management has very sufficient confidence in the company's various operating businesses and the landing of the humanoid robotics industry, while the management also disclosed to the public about the long-term lock-up announcement of the shares."

Ubtech was listed on the Hong Kong Stock Exchange in December 2023, raising net proceeds of HK$931 million. After the listing, it conducted two placements to raise more than HK$1 billion.