Tesla Boosts Stock Offering

Tesla Motors Inc. on Friday boosted the size of its stock offering, unveiled just a day earlier, by more than $140 million.

Shares of Tesla, which rose on Thursday after the stock sale was announced, added another 1% to $244.75 a share in premarket trading.

The electric-car maker said it now plans to sell about 2.69 million shares, up from the 2.1 million shares it said it would sell on Thursday. At the offering price of $242 a share, the sale would raise about $652 million.

That figure excludes an option for the offering's underwriters to purchase shares. If the underwriters purchase those shares, the offering would total $750 million.

The new round of fundraising that suggests the cost of disrupting the global auto industry with its pricey electric vehicles is more expensive than Chief Executive Elon Musk initially thought.

The stock sale comes on top of more than $4 billion Tesla has raised since the beginning of 2013. The auto maker has sold convertible notes and obtained lines of credit during that period to fund its ambitious bid to move from niche luxury-vehicle maker to a sizable force in the car business.

While the Palo Alto, Calif., auto maker consistently has expanded revenue during that two-year period, its net losses have deepened. And the company continues to burn large sums of cash on capacity expansions and new products.

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