Shares of Hyzon Motors Inc. /zigman2/quotes/223163959/composite HYZN -1.16% , a supplier of hydrogen-powered commercial vehicles, fell 16% in premarket trading Wednesday, after the company disclosed a regulatory subpoena stemming from a short-selling report. The company said the Securities and Exchange Commission has subpoenaed certain documents and information relating to allegations made by Blue Orca Capital, and said it is cooperating with the request. Blue Orca wrote in September that Hyzon is a "Chinese Lordstown Motors," referring to the electric truck maker /zigman2/quotes/211334938/composite RIDE -3.52% which ran into trouble last year when reports on preorders were found to be inaccurate. "In our opinion, Hyzon's supposed major customers are a fake-looking Chinese shell company incorporated three days before the deal announcement and a tiny New Zealand startup which told us they are not really a customer," the short seller wrote in the report. Hyzon made the disclosure as it offered an update on 2021 deliveries, which totaled 87 fuel cell powered heavy-duty vehicles, ahead of its guidance for 85 vehicles. "The company anticipates the 2021 financial results will reflect both lower average selling price per vehicle due to product mix and multi-year revenue recognition for the majority of sales, which will result in materially lower than forecast revenues and margins," it wrote in the filing. Shares have fallen 41% in the last 12 months, while the S&P 500 [s:" spx] has gained 24%.