In a matter of minutes, about $2 billion of Tesla Motors' (NASDAQ:TSLA) market capitalization was slashed this evening. The stock fell as much as 10% in after-market trading hours after the company posted its third-quarter letter to shareholders [link opens in PDF].

Tesla reported non-GAAP EPS of $0.12 and non-GAAP revenue of $603 million, up 9% sequentially. Tesla beat EPS and revenue estimates, with a consensus for $0.11 and about $535 million for EPS and revenue, respectively.

Vehicle sales were basically in line with Tesla's guidance: just over 5,500. Tesla had guided for "slightly over" 5,000 Model S deliveries in Q3. The company reached a weekly vehicle production rate of 550.

Tesla's automotive non-GAAP gross profit margin (excluding zero-emission vehicle, aka ZEV, credits) continues to improve rapidly, up to 21% from 14% last quarter. Management says they remain confident Tesla will reach its target automotive gross margin of 25% by Q4. Even more, management now says that Tesla may see further progress beyond 25%.

Going forward, Tesla expects to deliver "slightly under 6,000 Model S vehicles in Q4." That brings Tesla's expectations for full-year deliveries to 21,500 -- boosting the company's full year guidance by 500 vehicles.

Tesla says research and development costs should accelerate by about 25% in Q4 as Tesla accelerates "product development efforts on Model X and Model S enhancements."

To get more details on Tesla's third-quarter results, tune in live to Tesla's third-quarter earnings call, or if you miss it listen to a replay here here.

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