Tesla Motors Inc. on Wednesday indicated the company has yet to complete a so-called “alpha” engineering prototype of its forthcoming Model 3 electric car, which is due in 2017.

The disclosure, coming in its annual proxy filing with the Securities and Exchange Commissions, offers a rare glimpse into the status of one of the company’s most anticipated projects. The Silicon Valley electric car maker’s past disclosures indicate there is still plenty of time to complete the prototype and still launch on target.

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