HONG KONG (BLOOMBERG) - Elon Musk offloaded a second batch of Tesla shares in a matter of days and is now three-quarters of the way done selling 10 per cent of his stake in the company.

Tesla's chief executive officer got rid of 934,091 shares for more than US$884 million (S$1.2 billion), according to regulatory filings dated Thursday (Dec 16).

The sales were to pay for taxes on the exercise of 2.2 million options. Mr Musk has been on a selling spree since he asked Twitter users on Nov 6 whether he should offload part of his stake in the electric-car maker.

The world's richest person had said he would exercise options towards the end of the year and had set up a stock-trading plan prior to the poll.

Mr Musk has now sold 12.9 million shares for US$13.6 billion. He will need to dispose of about 17 million shares to offload 10 per cent of his stake, assuming his pledge excludes exercisable options.

Tesla shares fell 1.7 per cent as of 5.30am New York time Friday, before the start of regular trading. The stock has dropped 25 per cent from its peak on Nov 4. Mr Musk, 50, remains the world's richest person with a $243 billion fortune, according to the Bloomberg Billionaires Index.