What happened

Shares of Rivian Automotive (RIVN -2.27%) hit their lowest level in more than four months today. The stock was trading at the lows of the day, down 11.9% at 1 p.m. ET. That comes ahead of Rivian's third-quarter earnings report coming after the bell today. 

So what 

Investors are looking for the company to report a loss of about $1.80 per share on sales of $550 million. But that's not really what they will be focused on. Rivian is still in its early stages of growth, and the top- and bottom-line results likely won't move the stock. It could be demand that is the focus, and the shares may be getting hit today after fellow EV start-up Lucid Group reported a drop in its reservations last night.

Rivian electric trucks driving off-road at dusk.

Image source: Rivian Automotive.

Now what

Rivian has already announced that it produced 7,363 vehicles -- and delivered 6,584 -- in the third quarter. Revenue estimates are based on that data, but investors probably won't react even if the realized price per vehicle fluctuates one way or the other. What they want to know is how the company has been managing costs, how demand looks, and whether Rivian is making progress ramping up its production rate. 

Rivian produces electric adventure pickup trucks, SUVs, and electric delivery vehicles, so it's not a direct competitor with luxury EV maker Lucid. But Lucid reported a more than 8% drop in reservations over the last three months. That could be due to factors that won't affect Rivian, but some investors today might be trying to guess that Rivian will also report a drop. 

If so, that's not a smart way to invest. It is worth watching how the company's R1 platform preorders have changed since it last reported they were nearing 100,000 as of June 30. Rivian has said it expects to produce 25,000 vehicles this year, including its commercial vans.

It could also have lost reservations, as customers may not want to wait extended periods for delivery, especially with more electric options from competition entering the market. But it will be more critical to hear what Rivian says about its production rate and any insight into costs.