The U.S.-listed shares of Ballard Power Systems Inc. /zigman2/quotes/205070617/composite BLDP -0.33% lost 0.7% in premarket trading Wednesday, after the Canada-based fuel cell products company reported second-quarter results that missed expectations as gross margin that turned negative, and said it expects pressure on gross margin to continue for the rest of the year. Net losses widened to $55.8 million, or 19 cents a share, from $21.9 million, or 7 cents a share, in the year-ago period. The FactSet consensus for per-share losses was 12 cents. Revenue dropped 16.4% to $20.9 million, below the FactSet consensus of $24.6 million. Gross margin swung to negative 11% from positive 15%, due to a shift to lower overall product margin and service revenue mix, including impacts of pricing strategy, higher fixed and overhead costs, higher warranty provisions, higher supply costs and inventory adjustments. For 2022, the company cut its guidance range for capex to $30 million to $50 million from $40 million to $60 million, citing a "challenging macroeconomic outlook." The stock has soared 26.3% over the past three months through Tuesday, while the S&P 500 /zigman2/quotes/210599714/realtime SPX -1.51% has gained 3.0%.