(Reuters) – Hyzon Motors has received a subpoena from the U.S. Securities and Exchange Commission (SEC), the hydrogen fuel-cell truck maker disclosed in a regulatory filing on Wednesday, sending its shares down nearly 13% before the bell.

The SEC has asked the company to produce documents and information regarding allegations made in a report by short-seller Blue Orca Capital.

Blue Orca in September disclosed a short position in Hyzon and alleged that the truck maker’s largest customer Shanghai HongYun was a “fake company” and that it was formed days before announcement of a deal to supply 500 fuel-cell vehicles.

In October, Hyzon rejected the report and its chief executive officer said the company has no record of the short seller meeting with the management requesting “any information or clarification” or seeking “to verify its claims”.

Hyzon said on Wednesday it was cooperating with the SEC in the investigation.

Blue Orca and the SEC were not immediately available for comment.

Hyzon, which is designing a purpose-built hydrogen-powered truck called SuperH2Truck, went public in July 2021 through a merger with a blank check firm.

The company’s shares recovered some losses and were down 9% in premarket trading.

(Reporting by Akash Sriram in Bengaluru; Additional reporting by Eva Mathews; Editing by Sriraj Kalluvila)