Tesla stock's dazzling rally is thanks to CEO Elon Musk's renewed focus on the EV maker, activist investor says

• Tesla's massive share-price rally is thanks to Elon Musk's increased role at the EV maker, activist investor Ross Gerber said Thursday.
• "We just have seen full-fledged how Elon's focus makes such a huge difference," Gerber told Yahoo Finance.

Tesla CEO Elon Musk deserves most of the credit for the stock's dazzling rally over the past month, an activist investor in the company said Thursday.

Ross Gerber – who briefly ran for a board seat at the EV maker in February, promising to reign in the world's richest man – told Yahoo Finance that Musk had addressed his concerns by shifting his focus from Twitter to Tesla.

"I didn't want any change in Tesla's management – I wanted change in Twitter's management, which is what we got by getting Elon back at Tesla," Gerber said.

"Just in the 30 days that Elon's really been refocused on Tesla – signing up the entire world to the Tesla charging infrastructure, having very, very positive meetings in China – we just have seen full-fledged how Elon's focus makes such a huge difference," he added.

On May 12, Musk announced that Linda Yaccarino would replace him as CEO.

Since then, he's embarked on a high-profile tour of China and inked deals that will let Ford and GM customers use the company's sprawling supercharger network.

Musk's renewed focus on Tesla has coincided with its stock embarking on a breakneck rally.

Shares are up 52% since Yaccarino was announced as Musk's replacement, adding around $300 billion to the company's total market capitalization.

"The stock market has responded, and institutional investors have come back into the stock, and now we're back to the valuation that Tesla deserves," Gerber said.

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