Tesla's third-quarter operating income fell 56 percent to $718m on flat revenue of $28.0bn as operating expenses rose 39 percent

$718m. That was Tesla's third-quarter operating income, down from $1,624m a year earlier, according to the quarterly update the company filed with the SEC on Wednesday afternoon. Revenue barely moved, at $28,046m against $28,095m.

The gap is in the cost line. Operating expenses rose 39 percent to $4,776m, which the company tied to its Super Intelligence and other research projects, stock-based compensation including the 2025 award to its chief executive, and administrative costs. Net income attributable to shareholders fell to $787m, or $0.22 a share, from $1,373m, or $0.39. On the company's adjusted measure it earned $0.48, against $0.50.

Energy storage revenue fell 16 percent to $2,881m, and Tesla said tariff-related refunds to customers were part of the reason. Vehicle deliveries slipped 2 percent to 486,532.

Capital spending more than doubled to $4,732m, leaving free cash flow of $1,531m against $3,990m a year earlier. Cash and investments ended the quarter at $45.4bn. Tesla also reported that Cybercab rides began in Austin on September 3 and that its Texas Megapack plant has started production.