Ark Invest CEO Cathie Wood increased her purchase of Tesla shares even though there are growing concerns about Elon Musk's ability to run the business. Following this, Tesla rose 2.4% at the US premarket on Wednesday.

Shares also rose after Musk confirmed that he would step down as head of Twitter as soon as a replacement was found. It eased investor fears that the CEO was spending too much time on the social media company.

However, the overall trend for the stock remains bearish.

Ark Invest bought over 445,000 Tesla shares since October 3, when they began their latest buying spree. Last quarter, the amount that the company bought was about $88 million.

But despite this, Tesla's weight in the firm's flagship fund fell to third place from pole position, primarily due to the 61% drop in its share price this year.

Musk has been in the spotlight due to growing criticism of his involvement with Twitter, as well as growing concern from investors who have openly said there needs to be a change in Tesla's management.

Wood's flagship Ark Innovation ETF is down 66% for the year, much lower than the 32% drop in the Nasdaq 100, which was caused by the historic tightening of the Fed and fears of global recession.