Nikola founder Trevor Milton to voluntarily step down as executive chairman

Nikola announced early Monday that founder Trevor Milton is voluntarily stepping down from his roles as executive chairman and a member of its board.

The electric truck company said the board accepted Milton's resignation, adding that Stephen Girsky, former vice chairman of General Motors and a member of Nikola's board, has been appointed chairman of the board, effective immediately.

"Nikola is truly in my blood and always will be, and the focus should be on the Company and its world-changing mission, not me," Milton said in a statement. "So I made the difficult decision to approach the Board and volunteer to step aside as Executive Chairman. Founding Nikola and growing it into a company that will change transportation for the better and help protect our world's climate has been an incredible honor."

The announcement comes after short-selling firm Hindenburg Research accused Nikola of fraud. The company pushed back on the accusations, saying there were "dozens" of inaccurate allegations in the report. The Securities and Exchange Commission and Department of Justice are reportedly investigating claims that the company misled investors.

Hindenburg alleged Milton had made false statements about Nikola's technology in order to grow and secure partnerships with automakers.

In an early Monday tweet, Milton said, "I intend to defend myself against false allegations leveled against me by outside detractors."

GM recently took a 11% stake in the company and said it will produce Nikola's marquee hydrogen fuel cell electric pickup truck the Badger by the end of 2022. Last week, GM CEO Mary Barra said the automaker conducted "appropriate diligence" regarding a $2 billion deal with the electric vehicle start-up.

Nikola has been wildly volatile this year, rising from $13 at the beginning of May to a current 52-week high of $93.99 in June. The Nasdaq-traded shares finished Friday at $34.19.

The company's average volume over the last 10 trading days has come in at 53.2 million shares, though it has only about 361 million shares outstanding.

Nikola CEO Mark Russell said the company remains committed to its objectives and creating value for shareholders.

"Our priorities remain unchanged and, in collaboration with our partners, we are laser-focused on executing on our strategic initiatives and laying the groundwork to become a vertically integrated zero-emissions transportation solutions provider," Russell said in a statement.

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