New York (CNN) Larry Ellison's first year on the Tesla board has been very, very profitable.

Ellison, the co-founder of Oracle Corporation and one of the world's richest men, joined the Tesla board on Dec. 27, 2018. Before he did, though, he purchased 3 million shares of electric carmaker's stock, the company said late last year.

The closing value of those shares the day he joined the board was about $948 million, a stake representing 1.7% of Tesla shares. That makes him the second largest shareholder on the board after CEO Elon Musk.

Tesla TSLA For the first six months, Ellison's investment looked like a bad bet.shares tumbled 43% before hitting a 52-week low of $179.61 a share on June 3.

But since then the stock has been on a tear. On Monday Tesla stock crossed $500 a share for the first time in the company's history, and it kept climbing Tuesday as a variety of stock analysts raised their target price for shares. Even with a slight decline in shares on Wednesday, the stock price has nearly tripled in value since the June low and is up 68% since the day Ellison joined the board.

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