Elon Musk, the world's wealthiest person and chief executive of Tesla Motors, declined a philanthropic opportunity with Bill Gates after he accused the Microsoft founder of shorting stocks of the world's biggest electric vehicle manufacturer.
The issue came to light after Mr Musk responded to a question on Twitter on whether or not screenshots shared on the platform by a user named Whole Mars Catalog on Friday were authentic.
The first screenshot appears to show a text from Mr Gates confirming a day and time to meet Mr Musk, with both exchanging pleasantries afterward.
The conversation then turned into some sort of battle of the billionaires. Mr Musk said he responded because he had heard about Mr Gates' position on Tesla during a recent TED conference, but he was not the one who leaked to the media or anywhere else.
“Sorry to say I haven't closed it out,” Mr Gates responded, the screenshots showed, then added, “I would like to discuss philanthropy possibilities.”
That is when Mr Musk – who is not known for restraint on Twitter – wrote: “Sorry, but I cannot take your philanthropy on climate change seriously when you have a massive short position against Tesla, the company doing the most to solve climate change.”
In the stock market, a short position is, in the simplest terms, betting on a stock to fall.
On Friday evening, Mr Musk sent a follow-up tweet that was apparently mocking Mr Gates, who has yet to respond.
Tesla and the Bill and Melinda Gates Foundation have not commented on the issue.
Mr Musk and Mr Gates have a long history of disagreements on a number of topics, including on colonising Mars.
Most recently, in 2020, Mr Musk tweeted that his conversations with Mr Gates have been “underwhelming” after the latter revealed he bought an all-electric Porsche Taycan – instead of a Tesla.
They were on the same side at one point during the coronavirus pandemic, as both supported programmes by funnelling funds to organisations in an effort to help in the fight against the crisis.
But when Mr Musk suddenly questioned the severity of the coronavirus – including criticising stay-at-home orders and doubting the number of fatalities – Mr Gates replied by saying that the Tesla boss's “positioning is to maintain a high level of outrageous comments".
This is also was not the first time Mr Musk has speculated on Mr Gates's position on Tesla.
Last year, in an interview with CNBC, Mr Gates said “we need more Elon Musks”, a call for more entrepreneurs to respond to the challenges on climate change.
However, when asked on Mr Musk's speculation on the EV maker, Mr Gates appeared to sidestep the question: “I don’t talk about my investments but I think he should be very proud of what he’s done.”
Tesla's stock closed about 0.4 per cent lower this week, and is down around 16 per cent year to date. It currently has a market capitalisation of about $1 trillion.
On Thursday, it reported its largest quarterly net profit at the end of March – surging 658 per cent year-on-year and exceeding the $3 billion mark for the first time – as it delivered a record 310,048 vehicles in the last quarter, which was 68 per cent up on a yearly basis.
Mr Musk and Mr Gates are first and fourth on the Bloomberg Billionaires Index, with an estimated wealth of $259bn and $127bn respectively.
Mr Musk surpassed Mr Gates as the world's second-richest individual in November 2020, eventually topping Jeff Bezos, the founder of the world's biggest e-commerce platform, Amazon, in January 2021 to become No 1.
