Last month, when General Motors announced a $300 million investment in the factory that builds the Chevy Bolt EV, it also left a mystery about what else it might build at the plant.

Now a new trademark filing, first revealed by GM Authority gives a hint.

General Motors said it would use the factory investment to build a new electric car to sell alongside the Bolt. Based on previous GM presentations, that vehicle was likely to be a small electric SUV, although GM hasn't confirmed that those plans are still on. 

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On April 9, GM filed for a trademark on the name "Bolt EUV," with the U.S. Patent and Trademark Office, for use on "motor and land vehicles, namely automobiles."

The trademark filing does not indicate what the acronym might stand for, but if the "Bolt EV" stands for "electric vehicle," and "SUV" stands for "sport utility vehicle," it stands to reason that "EUV" might refer to an "electric utility vehicle," giving a little more affirmation to the rumors that the Bolt's new sibling could be an electric SUV or crossover vehicle. 

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GM has confirmed that the new car at the Bolt's Orion assembly plant will be built on that car's BEV2 electric-car underpinnings, rather than the company's upcoming BEV3 platform, which is expected to debut in its first luxury electric model, a Cadillac SUV, in 2022.

Meanwhile, it's looking quite likely that the company might pave the way with an electric SUV from Chevrolet.