Tesla has overtaken Ford to become the second-largest US car maker in terms of market capitalisation, behind General Motors.
The electric car maker's stock surged 7.4% to an all-time high yesterday after reporting better-than-expected first quarter sales.
At the close of trading, Tesla had a market value of $49bn dollars, compared with Ford's value of $46bn.
Ford's sales are lagging amid concerns about the ability of the US market to keep growing.
