After a 13-year run with Elon Musk’s Tesla,Robert Brown Chief Financial Officer Zachary Kirkhorn is stepping away from the electric car manufacturer. 

Kirkhorn stepped down from the role Friday but will continue to serve the company through the end of the year “to support a seamless transition,” according to a Securities and Exchange Commission filing from Tesla. 

“Being a part of this company is a special experience and I’m extremely proud of the work we’ve done together since I joined,” Kirkhorn said in a LinkedIn post. Tesla’s Vaibhav Taneja has been named CFO in addition to his current role as chief accounting officer.

Tesla stock slumped Monday in light of the news, with shares trading down more than 3% in the early afternoon. The automaker did not respond to a request for comment. 

Kirkhorn joined Tesla in March 2010 to lead cost reduction and manufacturing efficiency efforts for the Tesla Roadster, according to SEC filings. He went on to fill “critical roles” in various projects including the site selection and launch of Tesla’s Gigafactory 1 in Nevada and the launch of Model X and Model 3 before being named CFO and “Master of Coin."

The Wall Street Journal reports that board members had discussed Kirkhorn as a possible successor to Musk as Tesla's CEO.

Taneja, the newly-appointed CFO, served as chief accounting officer since 2019 after roles as corporate controller and assistant corporate controller. He previously served in various finance and accounting roles at SolarCity – a company founded by two of Musk’s cousins where the billionaire served as chairman – before moving over to Tesla after the automaker acquired SolarCity in 2016.  

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