Several US law firms are reportedly investigating the possibility of filing class-action lawsuits against Siemens Energy following the disclosure of wind turbine failures that led to a sharp drop in the company's stock price. In June, Siemens Energy's share price fell by as much as 36% after it reported a significant increase in the failure rates of wind turbine components manufactured by its Siemens Gamesa unit. The announcement came shortly after Siemens Energy took full control of the former Gamesa joint venture in late 2022.

At least six US law firms are now reportedly seeking injured investors and gathering more information about the circumstances surrounding the stock price decline. One of these firms, New York-based Pomerantz LLP, specializing in securities litigation, mentioned in July that its investigation was focused on whether Siemens and certain officers or directors engaged in securities fraud or other unlawful business practices.

Lawyers are particularly interested in the circumstances of Siemens Energy's purchase of the final third of Siemens Gamesa shares not already under its control, which brought the company under full ownership of the group. While no lawsuits have been filed yet, Siemens Energy maintains that it has not received any lawsuits related to the issue.

Siemens Energy has expressed confidence in its position, stating that the share price losses, while significant, do not constitute a legal breach of duty. The company believes that the markets were informed promptly, and only a small portion of its investors could potentially file a claim in the US.

In August, Siemens Energy revealed that ongoing turbine problems had significantly increased its expected annual loss to around $5 billion. It also estimated repair costs for Gamesa's onshore turbines to be approximately €1.6 billion.